The Application of Linear Programming For Forest Land Use and Timber Management Planning With Watershed Considerations In Terengganu, Peninsular Malaysia.
by
Ahmad Zainal Mat Isa
A PROFESSIONAL PAPER
submitted to Oregon State University
in partial fulfillment of the requirements for the degree of Masters of Forestry (Hydrology) (MF), Department of Forest Engineering, College of Forestry, Oregon State University, Corvallis, Oregon, 97331 United States of America.
Completed May, 1990.
Commencement June, 1990. AN ABSTRACT FOR THE PROFESSIONAL PAPER OF
Ahmad Zainal Mat Isa for the degree of Master of Forestry in Hydrology presented on May 18. 1990.
Title: The Application of Linear Programming For Forest Land Use and Timber Management Planning with Watershed Considerations in Terengganu. Peninsular Malaysia.
Abstract approved: Dr. Robert L. Beschta
The purpose of this paper is to illustrate the use of Linear Programming (LP) and other mathematical procedures to evaluate watershed and perpetuity constraintson forest land use for a selected scenario in Terengganu, Peninsular Malaysia. The paper describes the system of modelling and forecasting estimates of potential timber growth, forest harvest and inventory for use in planning with environmental considerations. The LP model provided a range of feasible solutions for decision making. Equationswere derived for the model to show interaction of sedimentation due to road construction, timber harvesting, and other related forest management activities.
Sensitivity analysis was used to test model behavior. A literature review provided information to supplement the findings gathered from simulation of the linear programming problem. The model further evaluated using theoretical, mathematical and
observational procedures. Results indicate the constraining effects of sedimentationupon forest revenues when sedimentation is allowed to vary within the feasible region of the model (i.e., from 600,000 m3/decade up to 1,150,000 m3/decade. APPROVED:
Professor of Forest Hydrology in charge of major
Head of Department of Forest Engineering, College of Forestry, OSU
Dean of Graduate School
Date thesis is presented May 18th. 1990 Typed by Roselina Abdul Rashid for Ahmad Zainal Mat Isa APPROVED:
Professor of Forest Hydrology in charge of major
Professor of Forest Engineering
Associate Professor of Forest Hydrology and Forestry Extension
Head of Department of Forest Engineering, College of Forestry, OSU
Dean of Graduate School
Date thesis is presented May 18th. 1990 Typed by researcher for Acknowledgements. The author wishes to express his gratitude and thanks to the following for making his anticipation and participation to pursue his graduate study in Oregon State University, Corvallis, Oregon, United States of America a reality and a possibility:
The Director-General and the Directorate of the Forestry Department of Peninsular Malaysia, the Public Services Department of Malaysia and the Government of Malaysia for the opportunity given to him to study abroad; The US-AID for sponsoring his training and graduate study; His major advisor, Dr. Robert L. Beschta, Professor in Forest Hydrology, Department of Forest Engineering, College of Forestry, OSU as well as the other members of his graduate committee, Dr. John Sessions and Dr. Paul W. Adams. Also the Head Department of Forest Engineering, Dr. William A. Atkinson and the Dean of College of Forestry, Dr. George W. Brown. Last but not least, to his wife, Roselina and their children, frnee, Irvinee, Muhammad frfan, Sill Sarah (deceased) and Sarah Aminah and to his mother, Halimali Daud for their inspiration, patience and love. TABLE OF CONIENTS
INTRODUCTION 1
OBJECTIVES OF THE STUDY 4
REVIEW OF LITERATURE 5
RESOURCE BASE AND THE SYSTEM OF LOGGING 27 PHYSICAL FEATURES OF THE STAlE OF IERENGGANU, PENINSULAR MALAYSIA 31
POLICY AND INSTITUTIONAL PROVISIONS 48
METHODS 53
DEVELOPMENT OF THE MODEL 56 Planning Horizon 65 Management Objectives 65 Management Choices and Alternatives 66 Harvest Control and Regulation (Management Constraints) 66 The Structure of the Model for Terengganu 67
RESULTS 81
SUMMARY AND CONCLUSIONS 90
LITERATURE CIIED 94
APPENDICES 103 Appendix 1 - Specifications for Forest Roads in Peninsular Malaysia 103 Appendix 2 - Map of the Distribution of Forested Area in Peninsular Malaysia 121 Appendix 3 - Map of Forest Types of Terengganu 122 Appendix 4- The List of Commercial Tree Species in Malaysia (1978) 123 Appendix 5 - Classification of Land for Forestry Use in Malaysia 127 Appendix 6- Slope Map Used in the Study 129 Appendix 7 - Detached Coefficient Matrix of the Terengganu Model 130 LIST OF TABLES
Tables Page
Distribution and extent of major forest types in Malaysia (million ha) 8 Forest resources of Malaysia (million ha) 10 Peninsular Malaysia: River Water Quality and Pollution, 1979-1983 14 Land use changes and sediment yield in Malaysia 24 Summaiy of suspended sediment and dissolved solid concentrations of selected watersheds in Peninsular Malaysia. 26 Summaiy of land elevations and its composition in Terengganu 33 Estimated forest area by forest types of Terengganu, Peninsular Malaysia as of December 31, 1981. 36 Estimated forest area allocated for National Parks and Wildlife Sanctuaries in Terengganu as of December 31, 1981. 37 Summaiy of gross volumes for all forest types in Terengganu - 30 cm and greater DiameterLimit 41 - 45 cm and greater Diameter Limit 42 - 60 cm and greater Diameter Limit 43 -90 cm and greater Diameter Limit 44 Summaiy of gross volumes of dbh greater than 45 cm for all forest types according to log quality in Terengganu. 46 Percentage damage adopted in SMS and study in Terengganu. 58 Forest management area as of December 1980 in Terengganu. 61 Average gross volume of average site for all forest types in Terengganu. 64 Estimation of increase in sediment production over background level for timber production in primary forests in Terengganu. 70 Summary of calculation of PNW objective function coefficient of the model. 73 Tabulation of calculated revenue per decade for each reference level of sedimentation per decade using formula. 86 Summary of the model scheduled harvest areas according to different feasible sedimentation levels with respective revenue generated. 88 LIST OF FIGURES
Figures Page,
The scale of forest loss in tropical countries of the world. 7 River quality index of Peninsular Malaysia. 15 Forest resource flow chart in Peninsular Malaysia. 30 The map location of the state of Terengganu. 32 A simplified diagram for a management planning model for logging operations in the hill forest of Malaysia. 60 Recovery rating curve showing declining effect of sedimentation through first three decades adopted in the study. 71 Normal curve to show the relationship of revenue per decade versus difference reference levels of sedimentation per decade. 82 Harvest-flow schedule from productive forests in Terengganu derived from the model study. 83 Overlay of normal curve of the calcullated revenue per decade using formula and computed model revenue versus sedimentation per decaJe. 87 Observations and least square regression line for both revenues computed. 104 1
THE APPLICATION OF LINEAR PROGRAMMING FOR FOREST LAND USE AND TIMBER MANAGEMENT PLANMNG WITH WATERSHED CONSIDERATIONS iN TERENGGANU, PENTNSULAR MALAYSIA.
INTRODUCTION
Renewable forest resources often provide important economic benefits in addition to their other values. Over the decades, man's interests and concerns related to forest resources have generally increased as indicated by the growing number of interest groups around the world. Today, these interest groups include engineers, economists, conservationists, environmentalists, biologists, mineralogists, industrialists, researchers, foresters and others, and have made forest resources the focus of their professional, intellectual, and research interests.
The utilization of endowed forest resources are often viewed as a key to economic growth and development for many countries throughout the world. Malaysia, particularly the state of Terengganu, is no exception. The basic issue is how to manage the forest resources of Terengganu for both tangible and the intangible products. The various interest groups are assumed to be equally responsible and provide important checks and balances to assure that the objective of generating maximum financial returns are consistent with the policy of "sustained resource flowu for the overall economic growth of the state of Terengganu, without violating or jeopardising watershed benefits and perpetuity constraints. Maintaining forest resources in perpetuity implies that the resources have yielded considerable benefits to the country. On a national basis, the forestry sector has contributed significantly towards the overall economic development of Malaysia. As a renewable natural resource, the forest will continue to provide viable economic returns to the country in terms of foreign exchange earnings, government revenue, income and employment. Currently, the forestry sector in Malaysia contributes approximately 7 percent of the country's Gross Domestic Products (GNP) and 13 percent of export earnings (Ministry of Primary Industries, Malaysia, 1989). Indeed, it is a question of how should the Permanent Forest Estate (PFE) be managed consistent with the the concept of viability and perpetuity while simultaneously seeking to maximize financial returns.
The PEE was delineated based on forest resources information and the need to maintain the forest as a renewable resource. This delineation was also in accordance with the guidelines of the Land Capability Classification (LCC) where most of the forested areas are categorised under Class IV and Class V of the LCC as defined below:
- Class IV - Land possessing a potential for productive forest development and therefore best suited to commercial timber production.
- Class V - Land possessing little or no mineral, agricultural, or forest development potential but suitable for development protective reserves for conservation, water catchment, game, recreation, or similar purpose, or possibly suitable in the future for productive forest plantations with introduced species.
Application of analytical tools, such as, scientific analysis, systems analysis and operations research are emerging which may help forest managers or administrators indentify the best alternative to achieve the objective.
The conflicting problem of commercial product maximization versus non-commercial value maximization can be resolved since all approaches to measuring benefits rely upon the same basic principle: the benefit value is measured in terms of the costs or quantities of other things foregone. 3
Concerns, satisfactions, dissatisfactions or social costs make it essential that any kind of measurement systematically account for all potential impacts. A system of environmental analysis, with an application of social values constraining benefits, in conjunction with the needs and desires of society, uses environmental parameters to help the forest managers or administrators reach rational forest land use decisions. The current urgency for planning and the accumulated planning experience, coupled with the increasing availability of computer technology and expertise, would almost ensure that the future application will intensify.
This study utilizes Linear Programming (LP) as a tool for forest land use and timber management planning with related watershed constraints for the state of Terengganu, Peninsular Malaysia. The National Forestry Enactment (Amendments) of 1986, for the state of Terengganu, Peninsular Malaysia, sets forth guidelines to ensure that timber management practices do not adversely affect other resource values. Through detailed forest land management planning, with substantial opportunity for public participation, the Enactment seeks to ensure that:
- the Permanent Forest Estate (PFE) will continue to be managed for multiple-use and sustained-yield of at least 700,000 m"3 of log production per year;
- the diversity of plant and animal communities will be preserved in selected areas;
- management activities will be confined to forest lands which are suitable for forest resource management;
- and timber harvesting will be conducted to minimize detrimental impacts on soil, water, wildlife, aesthetics, research and educational requirements, and other forest resource values. 4
OBJECTIVES OF THE STUDY
To generate forecasts and provide decade-by-decade estimates of potential timber growth, forest harvest, and inventory of Terengganu for the period 1971-2090 for use in timber management planning with environmental considerations.
To analyse and evaluate decision making for economic, silvicultural, and management implications with watershed and perpetuity constraints to achieve the integrated objective of maximizing financial returns. REVIEW OF LITERATURE
Concern for the environmental impacts of timber harvest in relation to soil and water resources is appropriate since the tropical rainforest of Malaysia is one of the most complex ecosystems in the world. It is a unique natural heritage which has evolved over millions of years and is rich and varied in plant and animal life. There are over 8,000 species of flowering plants, of which 2,500 are tree species, well over 200 species of mammals, 600 species of birds, about 110 species of snakes, 80 species of lizards and thousands of species of insects (Anon. 1989).
The forest also plays a significant protective role in the maintenance of safeguarding water supplies, ensuring environmental balance and minimizing damage to agricultural land. The success and development of the agricultural sector depends heavily on this protective function of the forest. As regulators of the country's water supply, approximately 97 percent of the fresh water supply for domestic, agricultural, irrigation, industrial and recreational purposes is derived from undisturbed forest watersheds (Ministry of Primary Industries, Malaysia, 1989). Most of the naturally forested watersheds are located in the hilly region and mountains. Effective management and conservation of these forest watersheds will help maintain a high quality water supply, reduce erosion and pollution of rivers and help to sustain the productivity of agricultural lands.
The Malaysian tropical rainforest is generally composed of the species-rich lowland and hill dipterocarp forests. Other forest types include mangrove and peatswamp forests, montane oak forest, and montane ericacious forest. The dipterocarp forests extend over large areas of the inland and uphill regions and are of vital ecological and economic importance to the country. The mangrove forests have an essential role in the protection and conservation of the coastal ecosystem for fisheries and aquaculture activities.
The conversion of forest land for agricultural purposes has been undertaken under a series of five-year development plans The rate of deforestation of rainforest in Malaysia is approximately 0.25 million hectares (ha) per year. This rate isconsidered relatively moderate in comparison to other tropical countries of the world as shown in Figure 1 (The Economist World Atlas and Almanac, 1989). The total forested land in Malaysia is estimated to be 202 million ha which accounts for 61 percent of the total land area (Table 1). The classification of tree plantation areas as forest increases the total forested land area to an estimated 74 percent and is expected to increase in the future because of ongoing reforestation projects. The distribution and extent of major forest types in West Malaysia (Peninsular Malaysia) and East Malaysia (states of S abah and S arawak) is shown in Table 1. Peninsular Malaysia has a total forested area of approximately 6.2 million hectares or 47 percent of the total land area (Table 1). Approximately 51 percent of total land area of the state of Terengganu is still covered with forest (Annual Report, Forestry Department of Terengganu, 1987). 7
[ DEFORESTATION IN TROPICAL COUNTRIES 8357 1.3 Am ef rainforsst lost per yur S hct.rss -1.2 Fçures Ir.CaTe area remarni9 lmhectares7.l7lrr cres -Os'-1.0
_Osi. .
:
: , II,H,'4,,,'MIIIIIIIIIIIIIIII
Figure 1. The scale of forest loss in tropical countries of the world (million ha per year). Source: World Resources Institute World Resources Report (198 1-85 average figures). 8
Table 1. Distribution and extent of major forest types in Malaysia (million ha)
Percentage Region Land Area,Dipterocarp Swamp Mangrove Forested Forested
Peninsular 13.2 5.6 0.5 0.1 6.2 47
Sabah 7.4 4.6 0.2 0.3 4.5 61
Sarawak 12.3 7 1.5 77 Malaysia 32.9 17.4 22 20.2
Source: National Forest Inventory of Peninsular Malaysia (1982). Forest Department, Peninsular Malaysia and Ministry of Primary Industries, Malaysia (1989). 9
Table 2 shows the breakdown of forest resources in Malaysia. In Peninsular Malaysia the designated PFE consists entirely of hilly lands above an elevation of 300 meters and slopes of at least 11 degrees (20 percent), except for smaller areas of mangroves and peatswamps that are retained for protection of coastal-plains environment. However, not all such hilly lands are included in the PFE: in certain areas, rubber is planted on slopes over 17 degrees (30 percent), ginger is grown on certain soil types at high elevations, especially in Cameron Highlands, state of Pahang Darul Makmur (Andel, 1978). For the purpose of this study, the resource base comprises mixed Dipterocarp hillforests on slopes from 11 degrees (20 percent) to 42 degrees (90 percent) which occupy approximately 51 percent of the total land area of the state of Terengganu, Peninsular Malaysia.
During the development of the Malaysian Peninsula, vast forest areas have been cleared for agricultural and other land development purposes. Large-scale exploitation of the tropical rainforests in Malaysia since the 1960's has considerably reduced the the amount of forested land. As a result, hillforests are increasingly harvested since available timber from the lowland has been substantially reduced over the last few decades. Furthermore, it is likely that logging activities, coupled with the inherent characteristics of Malaysian soils, will have substantial effects on the quality, quantity and timing of the water yield from forested watersheds. 10
Table 2. Forest resources of Malaysia (million ha)
Region Peninsular Category Malaysia Sabah Sarawak Malaysia
PFE 4.8 3.4 4.6 12.8
Productive 2.9 3.0 3.2 9.1 Protective 1.9 0.4 1.4 3.7 National Parks and Wildlife 0.6 0.5 0.3 1.5
Stateland Forests 0.9 0.9 4.6 6.4
Source: National Forest Inventory of Peninsular Malaysia (1982). Forest Department, Peninsular Malaysia and Ministry of Primary Industries, Malaysia (1989). 11
Despite several diverse hydrological studies of forested watersheds (Shallow, 1956; Leigh, 1968; Douglas, 1971; Low, 1972; Johari and Low, 1982; Abdul Rahim, 1985), relatively little is yet known of the hydrologic consequences of forest removal. The only studies that focus on the water balance of forested areas are those of Kenworthy (1969), Low and Goh (1972), and the Department of Irrigation and Drainage (DID), Malaysia (1982). In 1985, the Forest Research Institute of Malaysia (FRIM) research groups carried out an integrated watershed study at two sites; namely at the Bukit Berembun Reserved Forest, Negeri Sembilan, and at Jengka, Pahang Darul Makmur.
Forest hydrology research results throughout the world indicate that removal of forest cover increases water yield (Hamilton and King, 1983). After analysing 94 small watershed experiments, mostly in temperate zones, Bosch and Hewlett (1982) concluded that "no experiments, with the exception of perhaps one have resulted in reductions in water yield with reduction in forest cover".
The long-term management of natural forest resources for beneficial uses which include water, wildlife, recreation, etc., with emphasis on timber production involves a variety of on-the-ground activities (i.e., felling trees, limbing and bucking, yarding, transporting logs to mill sites, site preparation, slash disposal, road construction and maintenance, etc.). These activities can have important effects on stream systems and the quality of water:
A. Erosion - Erosion processes include surface erosion, mass soil movements such as landslides, channel erosion and others. Harvesting and roading
activities may accelerate erosion processes and availability of sediment to stream channels. Because of the concern for soil erosion from logging activities, particularly from logging roads and skid trails, guidelines have been developed in Malaysia to reduce damage [Forest Practice Rules of the National 12
Forestry Enactment of Terengganu (Amendments), 1986]. Soil erosion and siltation could be considered the most serious water pollution problem faced by Malaysia. The widespread occurence of soil erosion in Malaysia has been closely associated with the opening up of new land for agricultural purposes, logging activities, urbanization, infrastructure development and mining. The problems of soil erosion and siltation can probably be best overcome by various preventive measures that begin the initial stages of implementation and are continued.
Adams and Andrus (1990) cited that secondary roads for access and logging can be a major source of erosion and sedimentation problems in steep terrain. They estimated sediment production from forest road surfaces in Malaysia to be as high as 25 m"3 per 100 meters of road length per year. Road construction in Nepal created conditions 200 times more likely to cause land movement than the average of other human activities and the natural tendency of the terrain to slide. They identified that roadside gullies, slumps and landslides as the primary sources of stream sedimentation for a small forest catchment in Thailand.
Adams and Andrus (1990) also indicated that erosion damage that limits access can also have direct economic impacts, including reduced log values when transport delays result in decay or insect damage. They discussed both the applications and limitations of available information for reducing erosion and sedimentation from secondary roads and key considerations, which include the high intensity rains and related water volumes that are common in the humid tropics, as well as the widespread need for low-cost road design alternatives. 13
B. Suspended sediment - Suspended sediment is generally comprised of silt and clay particle sizes which are easily transported by flowing water. Suspended load sediment is usually directly correlated with turbidity, although a significant proportion of a stream's suspended sediment load may actually consist of organic materials. As indicated previously, the availability of suspended sediment can be greatly altered by forest management activities (Beschta, 1980).
During the development of Malaysia's land and natural resources, non-point sources of pollution increased and the majority of the country's rivers are polluted mainly by silt. In Peninsular Malaysia, between 1979-1983, 48 percent of the rivers were polluted because of the presence of high suspended solids centent as indicated in Table 3. Although none of the rivers in Terengganu was severely affected as shown in Figure 2, the quality of its rivers should be safeguarded.
Studies in the Pacific Northwest, USA, where typically there is a winter rainy season, have identified several insiream response patterns that relate directly to sediment availability in forested catchments (Beschta, 1983a).
These patterns include the hysteresis effect (or hysteresis loop) when the 14
Table 3. Peninsular Malaysia: River Water Quality and Pollution, 1979-1983
(Percent)
River Water Ouality
Clean Not Net Rate Index Rivers Improving Changing Deteriorating of Change * BOD 86 48 1 37 +5.5 ** NH-N 89 28 2 59 -4.0 3 *** SS 52 50 2 0 +8.5
River Pollution Polluted Not Index Rivers Improving Changing Deteriorating * BOD 14 2 0 2 ** NH-N 11 0 7 4 3 *** SS 48 17 9 22 Note: Based on water quality standards for fisheries: * BOD or Biochemical Oxygen Demand - 5 mg/i ** NH - N or Ammoniacal Nitrogen - 1 mg/i 3 * ** SSor Suspended Solids - 50 mg/i Source: Environmental Quality Report 1981-1984, Department of Environment, Ministry of Science, Technology and the Environment of Malaysia. 15
0 .14P.. ' $itmSS .aD1' P1 so s. SW.i I:io V'riiaP .c.ew P I_ SIiI I SMd 70 k.dU ai N
PPSSk -ji êO SI.S9I V 0 mS. can Ls4 Vsc
C
"
.44
SII%as
20 100 LC I-. Sat .1Rjvtr Cotdimu. lSquo s Mills). Rrvs Lws*y Afttsd by thi Oiidors wid Runcb frsn ini,iiu.
Figure 2. Peninsular Malaysia: River Water Quality Index of Suspended Solids, 1983. Source: Department of Environment, Ministry of Science, Technology and the Environment, Malaysia. 16
concentration of sediment is plotted against discharge for a given runoff event, (suspended sediment concentrations on the rising limb of a storm hydrograph are usually greater than those measured at equivalent flows on the falling limb); each succeeding runoff event tends to have higher suspended sediment
concentrations, as long as the flow exceeds that of preceeding runoff events. Similar phenomena have been observed in Terengganu, Peninsular Malaysia, during the rainy monsoon season.
C. Bedload sediment - Bedload sediment are comprised primarily of sand, gravel and boulders carried at high flows. For the case of Terengganu, bedload transport usually occurs in flood prone areas during monsoon season. Mass soil movement is common in most mountainous terrain and is the primarily source of bedload sediments. Landslides, avalanches, earthflows, slumps, and block glides are all forms of mass soil movement. These events can occur quite rapidly and are usually a mixture of soil, rock fragments, and organic
matter together with water. They occur as a result of both natural hydrologic events as well as due to forest and other management activities.
Generally, logging activities, particularly the construction of logging roads, have been identified as a major source of soil erosion and mass soil movement in the hillforest environment. This is particularly prevalent in highly weathered granitic soils where the soil structure is easily eroded. Measures which have been taken to minimize the problems include strict specifications on road alignment and construction, close control of felling and
skidding, and imposition of a higher minimum felling dbh limitor girth where necessary. 17
Studies in the Pacific Northwest, USA, have showed that compacted surfaces of logging roads, skid trails and fire lines often carry surface runoff during storm events (Brown, 1980). The same observation is made in Terengganu immediately after logging where road surfaces are a significant source of sediments in forests because of such runoff. The problem is compounded if road drainage systems are poorly planned or maintained because road surfaces not only inhibit infiltration and precipitation, but interdict normal sub-surface flow patterns as well. Surface erosion on roads have been observed to be most pronounced during the first season following construction (one or two years after treatment). Functional water bars on abandoned roads, skid trails are an essential part of minimizing accelerated soil delivery to stream or river system. Logging trucks hauling and skidding during wet weather on poorly surfaced roads may also increase the availability of fme sediments into streams and rivers. Yarding of logs to landings often causes soil disturbance and consequent erosion. With the advancement in cable logging technology, especially in temperate zones, alternative choices are available for difference topographic requirements and climatic conditions which can be adopted appropriately in the humid tropics. In other words, using the appropriate harvest system bearing in mind all the constraining factor, could avoid increased cumulative effects. Thus, planning is of utmost importance to avoid disturbance of the forest floor layer that protect the mineral soil from raindrop impacts and to insure that infiltration rates remain high to minimize surface runoff. 18
Keying logging method to soil types can prevent undue surface soil compaction and consequent surface erosion. Several alternative harvest methods are available which can significantly reduce compaction and soil disturbance, such as cable logging systems can be utilized to harvest timber where bulldozers and tractors would cause excessive soil disturbance on slopes greater than 17 degrees (30 percent). Vegetation management is also an important tool to control erosion from forest sites. Seeding grass or other cover species along forest roads to protect cut banks and fill slopes, landings and other areas of exposed mineral soil will help reduce surface erosion (Brown, 1980). Adequate compaction of fill materials during road construction could reduce erosion. Minimizing side cast material will also reduce erosion and sedimentation. Erosion could be avoided by end-hauling waste materials for placement in more stable locations. Alternative use of excavators to construct roads rather than bulldozers are encouraged because excavators are able to control the loss of soil material along the slope by using a bucket to dig rather than a blade to push soil or rock.
D. Organic debris loading - Organic debris loading is represented by the addition of tree boles and rootwads, leaves, twigs, and branches in stream or river system.
Large woody debris represents "large structural roughness elements" which influence the flow of water in stream channels and channel morphology
especially in creating and maintaining fish habitat as rearing pools. In the
PNW streams, woody debris is responsible for the location ofmany of the pools. In some streams, up to about third-order in size, single pieces of large
debris or accumulations of smaller pieces anchored by large piece oftencreate 19 a stepped longitudinal profile consisting of upstream sediment deposit, the debris structure, and a downstream plunge pool (Heede, 1972). From his flume study, Beschta (1983) illustrated that larger structures created longer and deeper pools, provided they are suspended above the streambed. Pools are deeper than riffles and their greater depth affords aquatic organisms suchas fish a better chance of escaping from terrestrial predators, and allows coexisting fish species or age classes to occur in layers within a water colunm (Fraser, 1969; Allee, 1982, and Bisson, 1987). This phenomenon of fish abundance and coexistence of different freshwater species in pools in Malaysian tropical forested streams has been observed by most fishermen and fisheries biologists.
Bilby (1985) demonstrated that pool area was positively correlated with the volume of the debris that anchored the pool, and that the correlation improved with increasing channel width in streams up to approximately 20m. From a geomorphic perspective, these forms of pools reflect bed topography and low water surface slope and gross aspects of hydrodynamics (for examplea plunge pool formed by scour below vertical fall, or a lateralscour pool formed by horizontally directed flow, or a dammed pool formed due to its position relative to the main channel backwater pools, and side channels).
By providing obstructions to water flow, large woody debris or other structures such root systems of woody vegetations along banks, large boulders, etc. increase the complexity of the stream or river habitat. Sediments stored by debris contribute to the hydraulic complexity especially in organically riched channels along low gradient alluvial valley floors. These areas oftenpossess a high diversity of riffles and pools (Keller and Swanson, 1979, Keller and Tally, 20
1979). Debris influences variation in channel depth by providing scour pools downstream from flow obstruction which, in turn, maintains a diversity of physical habitat by (i) anchoring the position of poois along the thalweg, (ii) creating backwaters along the stream margins, (iii) causing lateral migration of the channel and the formation of secondaiy channel systems in the alluvial valley floors and (iv) increasing depth variability.
In the Alsea watershed study in the PNW by Hall and Lantz (1969), extensive intrusion of logging slash and fine organic matter into a small stream resulted in impounded waters where fine organic matter accumulates (Dahm and Sedell, 1985). Similar situations occur in Terengganu when logging debris is transported by heavy rains, especially during the monsoon season.
The effects of fine organic debris upon dissolved oxygen are most pronounced when streams are at low flow and relatively warm (dry season). Gregory et al. (1987) advocated that valley landlorms influence patterns of particulate retention in streams and rivers. Location along a drainage also influences the ability of the stream to physically retain particulate inputs. The retention efficiency for particulate organic matter decreases from headwaters to large rivers (Minshall et al. 1983, Gregory et al. 1988) reflecting the decrease in both the relative streambed roughness (i.e., height of the roughness element relative to water depth, bed relief, and influence of adjacent riparian vegetation. Speaker et al. (1984) studied the process of retention of organic matter in streams in the Cascade Mountain Range of Oregon and found that the factors affecting retention includes channel morphology, hydrologic characteristics, substrate types and leaf characteristics. 21
Flow characteristics of stream reaches greatly influence the retention of coarse-particulate organic material. They studied the mechanisms responsible for retention and advocated that the channel roughness coefficient in the Manning's equation theoretically would provide an excellent measure of physical heterogeneity; however due to some constraints in high gradient mountain streams with cascading, turbulent flow, they expressed channel irregularity as a ratio of the wetted perimeter to the cross-sectional area of flow which is a better approximation of the probability of a particle in transport encountering the streambed. They also found that the presence of woody debris dams had major influence on reach retention patterns and stream reaches with major debris dams consistently had greater rate of retention.
E. Others - Dissolved load, stream temperature and the biological quality of water,
although of concern in some instances, are not specifically considered in this study.
With increasing steepness of terrain, forest management activities may cause surface erosion to become significant. The following assumptionsare inherent in this study:
(a)The existing method of tractor skidding reaches a limit, from an ergonomicor safety point of view as well as from erosion point of view, on slopes of
approximately 25 degrees (47 percent) as indicated by studies in Sabah, East Malaysia (Billington, 1982). One of the principal factors of augmenting soil erosion problems is the construction of unsurfaced and gravel roads without
proper planning and appropriate drainage structures. It has been indicated that the sudden increase in sediment load of Gombak River, in the state of Selangor, is due to new road construction and timber harvesting around the city of Kuala 22
Lumpur. The other factors are land slope and rainfall. Due to the wet climatic conditions and high intensity of rainfall in Terengganu, storms provide a tremendous amount of rainfall energy to the soil surface. As for the effect of slope on soil erosion, if the land slope is doubled (using degrees) then the amount of erosion per unit area is increased by approximately 3 times (Billington, 1982). Studies in Sabah showed that for extreme condition of exposed mineral soil or bare soil, the proportion may be increased up to 50 percent, indicating a possible 30 fold increase in overland flow with increasing velocities of flow (Billington, 1982). The energy to transport particles as sediment load also increases as a power of the velocity of flow. Thus, this study assumes that soil erosion occurs as a function of land slope although another important factor may be soil type and its inherent erodibility. For the purpose of this study, land slopes of up to 24 degrees (44 percent) are classified as "moderately steep slopes" or 51 and 25 degrees (47 percent) and greater are classified as "highly steep slopes" or S2. These classifications were derived to show the erosional effects of logging different slopes.
Felling wastage is an important problem in Malaysia and may make steepareas uneconomic to log. Conway (1976) has identified a critical slope of 33 degrees (65 percent) based upon North American research experience.
Poor construction of logging roads and improper skidding practicescan be major causes of erosion and sedimentation. This is especially true the firstyear following road construction during the rainy season when bare soil material is susceptable to erosion on cuts, fills, road surfaces, and ditches. In this study, the slope and road density factors are considered only in the primary forests
(PRF) because of the opening of new forest and construction ofnew roads. 23
The partially harvested forests (Pill and PH2) have existing logging roads. It is assumed these roads can be repaired and reused and that erosion is considered only in the first decade at the rate of 1 m'3/ha/decade for each
management unit. Thus, road density of up to50rn/ha is categorised as
'tmoderate road density" or Ri and51rn/ha and higher as "high road density" or R2. Ridgetop roads can minimize surface drainage volumes, and serve to reduce landslide frequency and size in unstable terrain (Sessions et al, 1987). Adams and Andrus (1990) cited that in order to access ridges, steep road grades may be needed and techniques are available for determining maximum grades so that trucks can climb without wheel slippage, based on the type of road surface and the vehicles used.
(d) Reduced vegetation cover may cause increases in flood flows and becomean integral component of increased soil erosion pertinent to the state of Terengganu. Results of studies in other parts of Peninsular Malaysia (Table 4) provide some evidence of sedimentation increases due to removal of vegetation cover for various land uses. Substantial removal of vegetation by management
activities such as, timber harvesting, road construction, grazing,or urbanization, can increase soil disturbance resulting in soil and nutrient losses
from watersheds, sedimentation of downstream receiving waters, andmore frequent occurrence of floods. In forested areas "buffer strips" of streamside vegetation of a specific width have become requirements in timber harvesting operations to minimize impacts on stream temperature as well as sedimentation. Dykstra and Froehlich (1976) evaluated stream protection
costs in Oregon and found that maintaining buffer strips55and150feet wide
along the stream channels resulted in timber volume foregone of 0 to 6 and 6to 24
Table 4. Land use changes and sediment yield in Malaysia
Location Land Use Sediment yield Source
Cameron Highland jungle 25 cu.m/sq.kmlyr Shallow (1956) tea 490 cu.nilsq.kmlyr Shallow (1956) vegetable 730 cu.mlsq.km/yr Shallow (1956) Gombak road construction 60 cu.mlsq.kni/yr Douglas (1968) logging 70 cu.m/sq.km/yr Douglas (1968)
Telom Catchment jungle 20 cu.mlsq.km/yr Douglas (1968)
Concentration
Damansara suburban 80,000 mg/i Douglas (1971) development (max. value) Douglas (1971) Pasoh Reserved Forestjungle 20 mg/i Leigh (1978)
Sungai Lui jungle 20 mg/i Lai (1985)
Damansara developed 3,200 mg/i Lai (1985)
Source: Lai (1985). Proceedings of the Workshop on Land Use Planning in Watershed Context. April 17-24. 1985. Jakarta. Indonesia. 25
17 percent, respectively.
Summary of suspended and dissolved sediment concentrations of selected watersheds in Peninsular Malaysia as an index or indicator is tabulated in Table 5.
(e)Guidelines imposed on road construction are based on the maximum slope and location for logging roads, rules for building in proximity to water courses, and requirements for the maintenance of buffer strips along water courses to reduce sedimentation of streams. Prescriptions for logging are identified for the following activities:
(i) Road planning, construction and maintenance.
(The specifications of the forest roads are as shown in Appendix 1 and is used as a guide). It is assumed that 40 percent of the totalarea of primary forest has Ri road density and 60 percent R2 road density based on the calculated area using digitizer.
(ii) Conservation measures are taken, such as: Filter strip and
Installation of cross-drains and culverts.
(iii) Recommended cutting regimes for Dipterocarps and
Non-Dipterocarps according to Selective Management System (SMS) with diameter at breast height limits. Supervised traditional logging using chainsaw for felling, ground-based Catterpillar bulldozer for
skidding and "sun-tai wong" or modified timber jinker for hauling is implemented. 26
Table 5. Summary of suspended sediment and dissolved solid concentrations of selected watersheds in Peninsular Malaysia.
Watershed Location Suspended Dissolved Remarks Source Sediment Solids (mg/i) (mg/i) Upper Gombak River 8 (mean) Forested Norris and state of Selangor condition.. Chartson (i962) i) Field Center 2-i 600 8-55 Forested cited in condition.. Peh (i96i) i2-i/2 Milestone 4-i080 10-83 Forested condition.. Douglas (1978) Tun Abdui RazakRd 2i-i070 i8-95 Some mining activities. Pasir River 2-5800 20-iio Effects of accelerated runoff from road surface significant Manan Kanan River, state of N. Sembilan 2-76 80 (mean)Forested condition.. Leigh et al. (in press)- cited in Peh (i98i) Tekam River state of Pahang Basin A 21-112 19-66 Forested condition.. Peh (198 i) Basin B 31-hO 4i-72 Forested condition Basin C 28-90 25-65 Forested condition Tok Pawang River state of Kedah i 8 (mean) Forested (control) catchment..Salleh et al. (1983) Bujang River state of Kedah 3-25 Disturbed forest SaIleh et al. (i 983) Rasau River state of Selangor i) WA 2-i300 4-i40 Disturbed forest Lai and Samsuddin (i986) 2) WB i-292 3-90 Disturbed..-do- 27
RESOURCE BASE AND THE SYSTEM OF LOGGING This study focuses on the implementation of the Selective Management System (SMS) in the mixed hill tropical forest of Terengganu, Peninsular Malaysia. The SMS has been practised in Terengganu since 1979 and has become an effective management tool for dealing with the variability encounted within the hiiforest ecosystem. In recent years, the location of the productive forest has shifted to the hilly areas due to a higher priority accorded the conversion of forest land for agriculture and agro-based industries and other land development. It is envisaged that after 1990, all of the agri-conversion forest or land conversion areas would have been completed and the timber supply will be available only from the productive parts of the PFE (Ahmad Zainal, 1986). A total area of approximately 577,242 ha (1 4 million acres) has been agreed upon by the State Government of Terengganu to be declared a Permanent Forest Estate (PFE), of which 287,200 ha (0.72 million acres) is primary productive forest. Based on 30- and 50- year rotations, the Annual Allowable Cut (AAC) for the period between 1986-1990 is targetted at approximately 10,200 ha out of. which 9,570 ha will be managed under a 30-year cutting-cycle and the balance of 630 ha will be managed under a 50-year cutting- cycle.
It is estimated that this area of productive forest will yield approximately 708,000 mA3 or about 500,000 tons of logs annually from 1986 onwards. These estimatesare based on a net industrial volume of 68 mA3/ha for Dipterocarps 50 cm in diameter and larger at breast height (dbh) and for other species 45 cm dbh and larger. In order to achieve the forest management and development objectives under the SMS, the cutting-cycle is targeted to be between 25-30 years due to reduction of the productive forests. 28
The SMS was established because: the system has the flexibility to manage the highly variable forest conditions and be adapted to changes in the socio-economic environment, it is rationally based on the inherent characteristics of the forest and the prevailing socio-economic conditions, and (iii) it will allow for the optimization of forest management objectives which include
an economic cut, the sustainability of the timber resource
and (c) the minimum cost for forest development. Under the SMS, a pre-felling inventory is carried out to provide information on stand characteristics through which optimum cutting limits are determined The parameters being measured in the pre-felling inventory include the following: (a) dbh size classes (above + 15 cm), (b) species,
and (c) stems per hactare;
incidence of weed species and climbers,
physiography by slope, elevation, soil type, and river system. Field data collected under the SMS field inventories include many plots and thousands of sample trees.
Appendix 2 shows the distribution of forested area in Peninsular Malaysia by recognised major forest types and geographic regions. Of this 6 2 million ha of forested area, 47 million ha is located in the proposed PFE. The resource base can be conveniently segregated into two broad categories (Forestry Department, Peninsular Malaysia, 1985), namely: 29
(1) Sustainable timber resource from the PFE based on intensive management of productive and operable forests comprising approximately 2.8 milion ha. (ii) Non-sustainable timber resource from forested land that is being converted to
agriculture and other uses at the rate of 80,939 ha per annum. Approximately 1.6 million ha are available for conversion. Figure 3 (Forestry Department, Peninsular Malaysia, 1985) indicates that a large portion of the productive forest areas in the PFE and the agri-conversion forest lands have already been harvested. 30
Toti3 forested land 6.12 I -I I Forested land suitable for agncuhure ProposedationaI pane; 144 forest estate 4.6$
Lcd Virgin forests Protecdi forests forests 146 0.31 forests 2.71 1.90 I Not reloggable Reloggable Virgin Log forests foresrs 0.73 forests forests I 0.73 0.96 3.12
ReIoggabk kegenerston forests forests 0.68 1.14
I Ba3ance of reloggable $a!ance of reloggabic forests forests 0.93 1.64
Thated Nontreated forests forests 0.56 0.5$ I Tiznber.producrng forests ailabk 2.5,
Figure 3. Forest resource flow chart in Peninsular Malaysia (million hectares). Source: Forest Department, Peninsular Malaysia (1985). 31
PHYSICAL FEATURES OF THE STATE OF TERENGGANU,
PENINSULAR MALAYSIA The state of Terengganu encompasses an area of 12,955 square kilometers and is located in the east coast of Peninsular Malaysia facing the South China Sea (Figure 4). Forested areas in Terengganu are typically associated with a wet climate. Sources from the Meterological Department of Peninsular Malaysia indicate that coastal areas receive 2600mm (102 in) of rainfall yearly while hinterland areas receive 3800 mm (150 in). The number of rain days per year averages 170 days. The greatest monthly precipitation typically occurs during the wet season from November through January, and sometimes into February. The lowest monthly rainfall amounts occur during April and May. Rainfall patterns are influenced by the Northeast Monsoon, with average windspeed of 14 rn/sec during the months of November through March. Maximum relative humidities range from a high of nearly 100 percent in the months of October and November and to a minimum of 68 percent during the dry months. The maximum daily temperature is 30.3 degrees Celcius (86.5 degrees Fahrenheit) for the coastal areas and the minimum daily temperature is 22.9 degrees Celcius (73.2 degrees Fahrenheit). Generally, land areas in Terengganu are low-lying, hilly and undulating, especially along the coastal areas and up to 30 kilometers inland. A summary of elevations is provided in Table 6. 32 SI : LAOS; THAILAND SI MALAYSIA AND KHMER NEPUSLIC : ADJACtNT TENNITONICS S . liii, II0000.óoe 17. N.s.a D .-,4 ...0 SOUTH ;: VICTNAM SIaUpSIW S 501.1 C SIAN S , ..'' 'S S..- '-,-
N.'. SOUTH CNINA SEA .%. I ._ , ..S.... t _. 5._n PENINSIaA MALAYSIA4-
SAAWAK u_S. lIr.$. S UMATRA rçl. w (INDONtSIA) IC AL. IN AN 1' AN (INDONESIA) N. 'Si N
Figure 4. The map location of the state of Terengganu. 33
Table 6. Summary of land elevations above sea level and its composition in Terengganu.
Elevation Composition (%) 0-75meter 60% 76- 150m 5% 151- 300m 8% 301- 900m 21% 901-1500m 5%
more than 1500 m 1 %
Total= 100% 34
Almost all high elevation areas with slopes of 11 degrees (20 percent) or greater are situated in the west of the state (from Hulu Besut in the north to the south through Hulu Terengganu, National Park to Hulu Kemaman bordering the state of Kelantan and Pahang Darul Makmur). The highest elevation is Lawit Mountain, Besut at 1,518 m. Most of the logging in hiflforest areas are carried out at elevations between 150-900 m or approximately 35 percent of the total land area of Terengganu. There are four principal rivers which flow from the west of the state towards the South China Sea. These rivers are (Appendix 3): Besut River which flows from the Hulu Besut watershed. Terengganu River which is the largest and longest river in the state and originates in the Hulu Terengganu and the National Park watersheds. A dam was constructed for hydro-electric power since 1984 at Kenyir, Kuala Berang. Dungun River with small tributaries in the hinterland of Hulu Dungun and the National Park watersheds. This river is also being used for water way to transport agricultural products to the town of Dungun. Kemaman River with tributaries in the hinterland of Hulu Kemaman watershed.
Along the coastal areas (and up to 2 km inland) soils are characterised asa "Marjne beach ridgett. "Deep peat" is also found up to 0.5 m deep along the coastalareas of Chukai, Kerteh, Merchang, Barn Rakit, Merang and Setiu. Most areas within the central portion and hinterland of Terengganu are covered with "Argilaceous" and "Arenaceous Sedimentary" soils. These areas include Hulu Besut, Gunung Tebu, Hulu Setiu, Petuang, Tembat, Hulu Terengganu, Pasir Raja, Jerangau, Bukit Terendak, Merchang, Bukit Bauk, Jengai, Sungai Nipah and Cherul. "Fluvatile" soils are found distributed in Gunung Tebu, Hulu Setiu, Hulu Nerus, Hulu Besut, and Jerangau. "Granite" is found in Bukit 35
Besi and Air Putih. Rock "Conglomerate" is found in Dungun and bicarbonate and carbonate rock in Air Putih, Kemaman. "Igneous plutonic" soils are found at high elevations, including Gunung Tebu, Tembat, Hulu Telemong, Chenderong Concession, Sungai Nipah, Bukit Terendak, Bukit Bauk, and Bukit Palus. Some mining was done in Hulu Kemaman around Cherul, Bukit Bandi and Air Putih. Logging cannot be carried Out during the wet Monsoon months of November through February and forest rehabilitation works can only be started in February through October. Thus, the effective working period comprises approximately 7-8 months each year. Large scale lumbering and logging activities in the past several years have caused some concerns regarding accelerated soil erosion and other negative hydrological and ecological impacts. Therefore, it is important that planning and monitoring of the forest land use and timber management for hiliforests in Terengganu, should be regulated to incorporate not only logging scheduling, log distribution, and silviculture development, but also soil and water protection. Soil and water considerations can affect decisions on which, when, and how much forest area is to be harvested. In 1981, the estimated forest area by forest types, excluding the National Park and Wildlife Sanctuaries, was approximately 580,516 ha (1,433,875 acres) (Table 7a and Table 7b). The total forested land area was estimated to be 662,184 ha (1,635,594 acres) which is approximately 51 percent of the total land area of the state of Terengganu (National Forest Inventory, 1982). Mangrove Swamp Forests occupy approximately 2,982 ha in addition to the total forested area; these swamps are being conserved as protective forests for coastal areas and for fish and other aquatic wildlife habitat. Forest resource map to show location of these forest types is depicted in Appendix 3. The inventory results for each forest type in gross volume per ha are summarized as follows: 36
Table 7a. Estimated forest area by forest types in Terengganu, Peninsular Malaysia (excluding National Parks and Wildlife Sanctuaries) as of December 31, 1981.
Forest type Size (hectares Percent (%)
1. Superior 112,763 19.4
2. Good 65,006 11.2
3. Moderate 96,545 16.6
4. Poor 20,138 3.5
5. Disturbed 8,165 1.4
6. Logged-over forest* 245,423 42.3 7. Poor Edaphic and
Upperhill forest 9,461 1.6
8. Swamp forest 17,241 3.0 9. Logged-over swamp
forest 5,774 1.0
Total 580.516 100.00
Source: National Forest Inventory of Peninsular Malaysia, 1982, Forest Department, Peninsular Malaysia. * Areas logged before 1977 37
Table 7b. Estimated forest area allocated for National Parks and Wildlife Sanctuaries in Terengganu as of December 31, 1981.
Forest types Size (hectares Percent (%')
1. Superior 39,491 48.3
2. Good 9,974 12.2
3. Moderate 11,260 13.8
4. Poor 3,196 3.9
5. Disturbed 1,528 1.9 6. Poor Edaphic and
Upperhill forest 16,219 19.9
Total 81,668 100.00
Total Forested Land = 662.184ha. Source: National Forest Inventory of Peninsular Malaysia, 1982. Forest Department, Peninsular Malaysia. 38
Superior Natural Forests These are natural forests occupying hilly terrain up to elevations of approximately 1,000 m and are capable of producing a gross volume of trees, with a diameter of more than 30cm dbh, ranging between 180 m"3/ha to 310 m"3/ha. The principal species are Red Seraya, Red Meranti (both Light Red
Meranti and Dark Red Meranti), Balau (Shorea spp.) and Kelat (Eugenia spp.). Most of these forests are situated in the north and in the west along the border with the states of Kelantan and Pahang Darul Makmur. They have the highest production per ha and consist of many large trees of Red Seraya and Red Meranti. The list of commercial tree species is as indicated in
Appendix 4. Good Natural Forests These are natural forests with undulating terrain up to elevation of 1,000 m and have a gross volume of trees, with a diameter of more than 30 cm dbh, ranging between 160 m"3/ha to 270 m"3/ha. The principal species are Red Meranti, Keruing (Dipterocarpus spp.), Seraya, Kelat and Balau. These forests are mainly located in Hulu Terengganu District bordering the state of Kelantan and some portion in Hulu Dungun in the south. Medium Natural Forests
These are natural forests with undulating terrain and hilly areas up to an elevation of approximately 1,000 m and have a gross volume of trees, with a diameter more than 30 cm dbh, ranging between 120 m"3/ha to 230 mA3/ha. The principal species are Red Meranti, Kelat, Keruing, Kempas (Koompassi 39 malaccensis) and Kedondong (Burseraceae family). These forests are situated in the west of Terengganu bordering the state of Kelantan and in the south bordering the state of Pahang Darul Makmur.
Logged-over Forests These are natural forests which have been logged after 1966 and have a gross volume of trees, with a diameter of more than 30 cm dbh, ranging between 110 mA3/ha to 220 m"3/ha. These forests account for 37 percent of the total forested land area in Terengganu. Disturbed Forests These are natural forests which have undergone soil erosion, shifting agricultural cultivation or were logged before 1966 and have a gross volume of trees, with a diameter of more than 30 cm dbh, ranging between 50 m"3/ha to 160 m"3/ha. Principal species are Red Meranti, Kelat, Kedondong, Kempas and Medang (Lauraceae family). These forests are located throughout the Reserved Forests but mostly in the south portion of Terengganu. Poor Forests These are forests which are usually located in poor drainage areas or rocky areas with elevations up to 1,000 m and have a gross volume of trees, with a diameter of more than 30 cm dbh, ranging between 50 m"3/ha and 180 mA3/ha. These natural forests are located throughout Reserved Forests in the west of Terengganu. They have a low and log volume per ha and are often uneconomic to log. 40
Montane Forests These are natural forests which are located at elevation of more than 1,000 m and have a gross volume of trees, with a diameter of more than 30 cm dbh, ranging between 50 m"3/ha to 180 m"3/ha. The principal species are Kelat, Medang, Seraya, Red Meranti, and Kedondong. Natural Peat Swamp Forests These are natural fresh water swamp forests with peat soils located near coastal areas or floodplains and the mouths of large rivers and have a gross volume of trees, with a diameter of more than 30 cm dbh, ranging between 20 m"3/ha to 130 m"3/ha. Logged-over Natural Peat Swamp Forests These are natural fresh water swamp forests in coastal areas and floodplains of rivers which have been logged before 1966 and have a gross volume of trees, with a diameter of more than 30 cm dbh, ranging between 20 m"3/ha to 100
m"3/ha. A summary of gross volumes for all forest types in Terengganu according to dbh classes is tabulated in Tables 8a, 8b, 8c, and 8d. Gross volume per ha according to Log Ouality Three classes of log quality are used in the forest inventory. These are defined as follows:
Quality 1: Log form is straight and round and suitable for peeling for veneer or for plywood.
Quality 2: Log is not suitable for peeling because of being crooked or knoty but can be used for sawn-timber. 41
Table 8a. Summary of gross volumes for all forest types in Terengganu (m"3/ha)- 30 cm + Diameter Limit
Forest Type 30 cm + Diameter Limit Respective NQ NDFM NDPM Total Percentage (%)
Superior (1) 57.6 34.7 37.1 63.0 6.7 199.1 29,17,19,32, 3
Good (2) 24.6 40.4 48.5 70.4 10.0 193.9 13,21,25,36, 5
Medium (3) 23.8 39.4 32.0 41.6 2.6 139.4 17,28,23,30, 2
(1)&(2)&(3) 39.3 37.5 38.0 57.8 6.1 178.7 22,21,21,32,4
Logged (4) 21.1 21.7 29.6 49.8 7.7 129.9 16,17,23,38, 6
Disturbed (5) 5.7 6.6 26.1 49.4 8.0 95.8 6, 7,27,52, 8
Poor (6) 8.8 15.7 66.9 38.1 4.7 134.2 7,12,50,28, 3
Montane (7) 4.5 6.0 29.9 18.6 2.7 61.7 7,10,49,30, 4
(6)&(7) 6.5 10.6 47.5 27.9 3.7 96.2 7,11,49,29,4
Peat (8) 4.1 2.4 20.1 24.9 12.5 64.0 6, 4,31,39,20
L. Peat (9) 15.6 19.1 8.8 15.7 6.8 66.0 24,29,13,24,10
(8)&(9) 7.0 6.6 17.3 22.6 11.1 64.6 11,10,27,35,17
Note:D - Dipterocarps (Damar Meranti)
ND - Non-Dipterocarps (Damar Bukan Meranti) NDFM Non-Dipterocarps Fully Marketable (Bukan Damar Pasaran Penuh)
NDPM - Non-Dipterocarps Partially Marketable (Bukan Damar Separuh Pasaran) MS - Miscellaneous species (Pelbagai Jenis) Peat - Natural Peat Swamp Forest (Hutan Paya Gambut Asal) L. Peat - Logged-over Natural Peat Swamp Forest (Hutan Paya Gambut Dibalak) 42
Table 8b. Summary of gross volumes for all forest types in Terengganu (m"3/ha) - 45 cm + Diameter Limit
Forest type 45 cm + Diameter Limit Respective NT1FM NT1PM Total Percentage (%
Superior (1) 52.3 32.2 28.2 35.3 3.9 151.9 34,21,19,23, 3
Good (2) 18.0 33.1 28.3 40.3 6.2 125.9 14,26,23,32, 5
Medium (3) 17.5 29.1 17.7 10.9 - 75.2 23,39,24,14, 0 (1)&(2)&(3) 33.4 31.4 24.8 28.6 3.2 121.4 27,26,20,24, 3
Logged (4) 17.0 21.5 20.7 28.6 5.6 93.4 18,23,22,31, 6
Disturbed(S) 3.2 6.6 18.4 31.4 1.5 61.1 5,11,30,51,3
Poor (6) 6.6 5.9 38.9 7.6 4.2 63.2 10, 9,62,12, 6
Montane (7) 2.3 1.8 12.9 4.8 0.8 22.6 10, 8,57,2 1, 4
(6)&(7) 4.3 3.8 25.3 6.1 2.4 41.9 10, 9,60,15, 6
Peat (8) - 2.4 8.8 12.9 9.3 33.4 0, 7,26,39,28
L. Peat (9) 7.3 8.3 0.8 5.7 4.1 26.2 28,32, 3,22,15
(8)&(9) 1.9 3.9 6.8 11.1 8.0 31.7 6,12,35,21,26 43
Table 8c. Summary of gross volumes for all forest types in Terengganu (m"3/ha)- 60 cm + Diameter Limit
Forest type 60 cm + Diameter Limit
Respective NDFM NDPM M TotalPercentage (%) Superior (1) 45.3 28.7 22.3 20.8 2.7 119.8 38,24,19,17,2
Good (2) 11.7 28.4 22.3 21.0 3.5 86.9 13,33,26,24, 4
Medium (3) 8.3 20.4 5.1 4.5 - 38.3 22,53,13,12,0
(1)&(2)&(3) 25.9 26.0 16.8 15.6 2.0 86.3 30,30,20,18, 2
Logged (4) 11.3 16.9 13.4 13.5 4.7 59.8 19,28,22,23, 8
Disturbed(5) 1.9 5.8 4.6 21.5 - 33.8 5,17,14,64,0
Poor (6) - - 18.6 2.9 - 21.5 0, 0,87,13,0
Montane (7) 1.7 1.0 3.8 0.9 7.423,14,51,12,0
(6)&(70 0.9 0.5 10.8 1.9 14.1 6, 4,77,13,0
Peat (8) - - 3.4 3.8 7.2 0, 0, 0,47,53
L. Peat (9) - 6.2 - - 6.2 0,100,0,0,0
(8)&(9) - 1.6 - 2.5 2.8 6.9 0,23, 0,36,41 44
Table 8d. Summary of gross volumes for all forest types in Terengganu (mA3Tha) - 90 cm + Diameter Limit
Forest type 90 cm + Diameter Limit Respective D jQ NDFM NDPM M TotalPercentage (%')
Superior (1) 26.0 13.7 12.5 5.6 1.1 58.9 44,23,21,10, 2
Good (2) 2.3 17.0 8.1 4.9 - 32.3 7,53,25,15, 0
Medium (3) - 7.4 - - - 7.4 0,100,0, 0, 0
(1)&(2)&(3) 12.3 12.4 7.5 3.6 0.5 36.3 34,34,21,10, 1
Logged (4) 6.1 8.6 4.2 2.4 2.0 23.3 26,37,18,10, 9
Disturbed(5) 3.6 - 3.7 - 7.3 0,49, 0,5 1, 0
Poor (6) - - - 0, 0, 0, 0,0
Montane (7) - - - 0, 0, 0, 0, 0
(6)&(7) - - - 0, 0, 0, 0, 0
Peat (8) - 0, 0, 0, 0, 0
L.Peat (9) - 6.2 - - 6.2 0,100,0,0,0
(8)&(9) 1.6 - - 1.6 0,100,0, 0, 0
Source: National Forest Inventory of Terengganu, 1982. Forest Department, Peninsular Malaysia. 45
(c) Quality 3: Log is not suitable for peeling for veneer/plywood or for sawn-timber because of defects and can be used for other purposes. Estimation of gross volume per ha according to log quality is determined for species groups (i.e., Dipterocarps, Non-Dipterocarps, Non-Dipterocarp Fully Marketable, and Non-Dipterocarp Partially Marketable). Miscellaneous species are not included due to their low economic potential. However, these species may become more acceptable and marketable in the future. A summary of gross volumes of dbh greater than 45 cm for all forest types according to log quality is tabulated in Table 9. 46
Table 9. Summary of gross volumes of dbh greater than 45 cm for all forest types according to log quality in Terengganu (m'3/ha) Species group /quality Forest type Natural 5(1) G(2) M(3)L(4) D(5) P(6) M(7)P(8) LP(9) Dipterocarps Quality 1 49.4 18.0 17.5 12.2 3.2 3.9 2.3 - 7.3 Quality 2 3.1 3.0 2.7 - Quality3 1.8 - - - - Sub-total 52.5 18.0 17.5 17.0 3.2 6.6 2.3 - 7.3 Non-Dipterocarps Quality 1 24.5 25.6 24.8 17.9 6.6 3.9 1.0 2.4 8.3 Quality 2 5.5 7.4 4.3 3.3 - - 0.8 - - Quality 3 2.2 - - 0.3 - 2.0 - - - Sub-total 32.2 33.0 29.1 21.5 6.6 5.9 1.8 2.4 8.3 Non-Dipterocarp Fully Marketable Quality 1 25.8 23.1 10.1 15.3 16.1 36.6 9.7 7.7 - Quality 2 1.6 7.5 7.5 4.3 1.4 2.4 3.2 1.2 0.8 Quality 3 0.9 0.7 1.2 0.9 - Sub-total 28.3 31.3 17.6 20.8 18.4 39.0 12.9 8.9 0.8 Non-Dipterocarp Partially Marketable Quality 1 18.0 20.2 4.4 18.9 13.7 5.0 1.9 11.6 1.6 Quality 2 14.7 19.4 3.3 7.9 10.9 2.7 2.1 1.3 1.5 Quality 3 2.7 0.7 3.2 1.9 6.8 - 0.8 - 2.7 Sub-total 35.4 40.3 10.9 28.7 31.4 7.7 4.8 12.9 5.8 Total
Quality 1 117.7 86.9 56.8 64.3 39.6 49.4 14.9 21.7 17.2 Quality 2 24.9 34.3 15.1 18.5 12.3 7.8 6.1 2.5 2.3 Quality 3 5.8 1.4 3.2 5.2 7.7 2.0 0.8 - 2.7
Grand Total 148.4 122.6 75.1 88.0 59.6 59.2 21.8 24.2 22.2 47
Note for Table 9:
Forest types: S(l) - Superior Natural Forest G(2) - Good Natural Forest M(3) - Medium Natural Forest L(4) - Logged-over Forest D(5) - Disturbed Forest P(6) - Poor Forest M(7) - Montane Forest P(8) - Natural Peat Swamp Forest LP(9) - Logged-over Natural Peat Swamp Forest Source: National Forest Inventory of Terengganu, 1982. Forestry Department, Peninsular Malaysia. 48
POLICY AND INSTITUTIONAL PROVISIONS The National Forestry Policy of Malaysia (instituted in 1978) has the following principal objectives which are related to this study: (1) To dedicate as PFE sufficient areas of land strategically located throughout the country in accordance with the concept of rational land use in order to ensure: sound climatic and physical conditions of the country, the safeguarding of water supplies, soil fertility and environmental quality and the minimization of damage by floods and erosion to rivers and agriculture lands, such forest land being known as PROTECTIVE FORESTS;
the supply in perpetuity at reasonable rates of all forms of forest produce which can be economically produced within the country and are required for agricultural, domestic and industrial purposes, such lands being known as PRODUCTIVE FORESTS; the conservation of adequate forest areas for recreation, education, research and the protection of the country's flora and fauna, such forest lands being known as AMENTTY FORESTS.
Under the provisions of Section 10(1), Chapter 2 "Classification of Permanent
Reserved Forests" of the 1986 National Forestry Enactment (Amendments), of the state of Terengganu, forest land use is classified under one or more of the following classifications:
timber production forest under sustained yield; soil protection forest;
soil reclamation forest; flood control forest; 49
(e) water catchment forest;
(1) forest sanctuary for wildlife;
virgin jungle reserved forest; amenity forest;
education forest; research forest; and forest for federal purposes.
The descriptions for the above classification are as follows (Classification of Land For Forestry in Peninsular Malaysia, Forestry Department, Peninsular Malaysia, 1984): Timber production forest under sustained yield These are forest lands which are inherently productive or with high timber production potential and are capable of supplying timber which can be economically produced under sustained yield both for the domestic and export markets. Generally these are forest lands with average slopes of less than 40 degrees and with easy to moderately difficult access. They include Class 1 (Superior), Class 2 (Good), Class 3 (Marginal) and part of Class 4 (Restrictive) as defined in the classification. Soil protection forest
These are forest lands which are located in environmentally sensitiveareas and particularly on steep terrain. Exploitation and the absence of vegetation cover could result in soil erosion, flash floods, landslips, siltation, loss of nutrients and other forms of environmental degradation which could be detrimental to the well-being of the populace. Such forest when destroyed, 50 would require expensive alleviation and rehabilitation works. They include part of Class 3 (Marginal), Class 5 (Conservation) and Class 6 (Poor) as defined in the classification.
Soil reclamation forest These are generally low-lying forest lands usually formed through a gradual process of soil accretion and forest formation and include forests established on reclaimed lands. They may be seasonally or permanently subjected to inundation; mainly mangrove and inland swamps. They are equivalent to Class 4 (Restrictive).
Flood control forest These are forest lands that act as reservoirs for water storage during the monsoon season. The exploitation of such forests could result in massive downstream flooding which is not only undesirable but also detrimental to both agricultural crops and human life. Such forest lands can be identified through historical records and meteorological data on flood-prone areas in the state. Generally they include inland fresh water swamp (seasonal) and the peat swamp forests. Water catchment forest
These are forest lands which function as a regulating system against excessive runoff and have water retention capacity. They are vital for ensuring the supply of water to meet the increasing demand for domestic, industrial and agricultural uses. Proper management of such forests is essential for the maintenance of desirable water quality, stable stream flow regime, and the 51 avoidance of damaging floods. These areas consist of generally hilly forest land from which rainfall flows into a river system. Such forest is of particular importance where dams are constructed. Forest sanctuary for wildlife These are forest lands where indigenous wildlife exists in a significant numbers and which should be reserved for the protection of wildlife populations against human interference. Sanctuaries may be established for the protection of one or more species. Such forests are established to prevent the extinction of the already dwindling endangered species of flora and fauna in the country and are restricted to authorised persons undertaking activities compatible with the purpose of the sanctuaries. Virgin jungle reserve forest
These are forests which are established to serve as permanent nature reserves and natural arboreta, as controls for comparing with the exploited and silviculturally treated forests, and as undisturbed natural areas for general ecological and botanical studies. Amenity forest
The definition of Amenity forests in this context refers to forest lands which are conserved, developed and managed for recreational uses only. 52
(1) Education forest
These are forest lands which are identified or reserved for the purposes of furthering education and creating better public awareness with regards to the vital role of forest in the preservation of the balanced physical, social and economic environment.
Research forest
These are forest lands earmarked for research purposes. Among the research plots which have been set up throughout the state are Silvicultural Plots, Phenological Plots, Forest Plantation Plots, Ecological Plots, Big Tree Plots, Hydrological Plots, and Growth and Yield Study Plots. Forest for federal purposes
Constitutionally, forestry is essentially a state matter. So, these are areas to be allocated for Federal purposes such as the setting up of Continuous Forestry Inventory (CFI) Plots and Research Stations. In terms of forest productivity, the forest lands are classified into two broad classes: Productive forest land, and
Non-productive forest land using altitude as a parameter for classification. An
altitude of less than457meters(1,500feet) above sea level demarcates
productive forest land from the non-productive land which lies above457 meters(1,500feet).
The proposed classification of forest land has been revised by the Forestry Department of Peninsular Malaysia to include six slope classes. The revised classification of land for forestry use, which is used for the purpose of this study, is shown in Appendix5and the slope map is attached as Appendix 6. 53
METHODS
A model is to be developed that could be used as a tool for forest land use and timber management planning and to analyse the economic, silvicultural and environmental implications of management decisions in the state of Terengganu, Peninsular Malaysia. Potentially, the model could be expanded to include all of Peninsular Malaysia using additional variables.
The suggested mathematical applications to be used include: Linear programming (LP) and Theory and calculation procedures using mathematical equation of
R=Rmax { 1- 1Os} (1) where R = Revenue generated, US$/decade Rmax = Maximum revenue predicted/decade S = Sediments, m'3/decade k = Coefficient of reaction of considering sedimentation as a constraint and (iii)Comparison of actual revenues calculated
from formula, RfOa, and revenues generated from model simulation, 1mode1, as a control function.
Linear programming provides a methodology for allocating the management forest land among competing activities. Steep terrain, coupled with the seasonal high rainfall period, constitute two major problems in the management and logging of the hillforests in the study area. There is an urgent need for an improved management decision making 54 process and better logging techniques in the study area, not only for the maintenance of timber production but also for the protection of environmental values such as soil and water. For this study, forest management planning is defined as the control of the area harvested as well as volume and quality of logs removed during logging over an extended period of time. The proposed LP model will encompass a forest management and protection planning model for hiliforests of Terengganu. The Selective Management System (SMS), which has been applied in the study area since 1979, utilizes a minimum diameter cutting limit over a range of timber species to ensure sufficient residual stands of advanced regeneration for future production needs. This system is flexible and takes into consideration factors such as growth and mortality, adequate residual stocking, viable economic cuts, logging damage and wastage, silvicultural and environmental considerations. The economic cutting regime is determined by using the concept of financial maturity as adopted by Duerr et al. (1966). It is believed that by considering monetary values, the decision making process to determine which trees to harvest and which to leave for future utilization will be more implicit and accountable. Sensitivity tests on the model will reveal structural and/or logical defects, if any, in model behaviour.
Estimates of suspended sediment concentration and streamfiow in the hiliforest watersheds in the state of Terengganu, Peninsular Malaysia are available from the Department of Irrigation and Drainage, Terengganu and the Department of Environment, Terengganu respectively. Experiments in the Peninsular Malaysia by Rubber Research Institute of Malaysia in 1975 to determine the erodibility of 5 types of common local 55 soils, showed that on a 30 degrees slope (58 percent), bare soil samples had lost the following amount of soil in six months after 1010 mm (40 in) of rain had fallen
(Billington, 1982):
SOIL SERIES SOIL LOSS in tonnes/hectare
1)Muchong 100.0 2)Rengam 212.0
Serdang 339.0 Holyroad 252.0 Sungei Buloh 220.0 This tabulation indicates that the Serdang soils are more than three times as susceptible to soil erosion than the Muchong soils. The erosivity or the potential ability of rain to cause soil erosion depends on the climatic regime and characteristic of storms during the Northeast Monsoons. Thus, the preceeding tabulation provides only an approximation of soil losses resulting from forest harvesting operations. For the purposes of the study, Forest Land Capability developed on Land Capability Classification is assumed to apply to forestry operations. The mathematical expression of revenue as a function of sedimentation is derived by using the results of the LP simulation as indicated in equation (1). R = Revenue per period at any constraining level of sedimentation above background level of 5, and Rmax is the total or ultimate revenue predicted. The value of the coefficient k is solved by using Equation (1) after doing the simulation. Comparison of actual revenues calculated from formula and revenues generated from model simulation could be overlayed to show the relationship. 56
DEVELOPMENT OF THE MODEL A linear programming model was selected to maximize an economic objective function of mixed tropical hihiorest stands to provide estimates of forest production under different harvesting cycles (30, 40, 50 and 60 years). The linear programming model also provided a means of incorporating various limitations and constraints to achieve the overall objective. This simple model will hopefully expedite planning, implementation, and evaluation of alternative management practices. Model development included several assumptions: The model works under normal management practices; The average annual diameter increment of all commercial tree species (i.e., desirable residual stems 30 cm dbh and greater) is 0.8-1 cm per year;
The gross and net economic cuts of 60 mA3/ha and 30 mA3/ha, respectively,
will be met; The percentage of Dipterocarps in the residual stand >= percentage of Dipterocarps removed. The cutting limit is >= 50 cm for Dipterocarps and >= 45 cm for Non-Dipterocarps;
Damage to residual trees due to logging is assumed to be:
Tree diameter (cmi Damage (O
30-45 40
+45 30 The minimum standard for a sufficiently stocked stand is, as stated in the Disturbed Forest Inventory, 32 stems/ha (13 stems/ac) in the +30 cm dbh class. Results of pre-felling inventory data collected from 56,200 ha in 57 several compartments indicates that if any diameter cutting limit is applied within the stand, residual stems will be dominated by Non-Dipterocarps species;
The equivalence approach of residual stocking will be used only if (vi) is not satisfied. To get the highest possible harvest volume in the next cutting-cycle, the Dipterocarp component of the residual stock should not be reduced and this is achieved by applying split cutting limit for the Dipterocarp and Non-Dipterocarp. It is evident from past experience in Terengganu that the percentage damage to residuals is inversely proportional to the minimum diameter cutting limits and the effect of logging the smaller diameter classes would be more detrimental to the residual stand. The percentage damage adopted for this study, according to diameter class, is indicated in Table 10;
In the felling operation, licencees are required to construct proper infrastructure and logging roads according to specifications suitable for
Malaysian conditions as well as maintenance so as to minimize soil erosion, runoff and other catastrophic effects (Appendix 1);
All of the principal species are fully marketable;
Tree growth in diameter and in volume! unit area /unit time is assumed to be constant for all species but varied between size classes; The classification of forest stands used here is assumed to be the simplest case of practical use in a mixed tropical forest. The classification is: small size trees, < 15 cm dbh;
intermediate size timber, between 15 cm to 45cm dbh; and mature timber, >45 cm dbh. 58
Table 10. Percentage damage to residuals assumed in SMS and study in
Terengganu.
Diameter class (cm)Percentage damage (%)
+60 20
46-60 30
30-45 40
15-29 50
Source: Griffm, M and Caprata, M. (1977). 59
A simplified diagram of a management planning model for logging operations in the hillforest of Malaysia as shown in Figure 5, was used as a guide. Data from the National Forest Inventory II of Peninsular Malaysia (1982) was used in model simulations. The most feasible Linear Programming solution was further analysed and evaluated. Mathematical equation analysis was also carried Out to further evaluate the feasible solution, if any. A detached coeffient matrix (DCM), with input data on Terengganu forestry, was solved using a commercial HYPER-LINDO LP solution package. Several alternative forest management scenarios for Peninsular Malaysia have been developed and analysed by Yusuf (1987). A selected alternative forest management scenario for the state of Terengganu, Peninsular Malaysia was developed and analysed. The basic scenario represents a management situation where all the potential timber volume in species currently marketable and for trees 45 cm dbh and above are harvested. This dbh limit is selected because it represents the minimum dbh of trees which are considered for harvesting in the SMS. Furthermore, 45 cm is the lower point of one of the dbh classes in the 1972 inventory data and the subsequent 1982 inventory. The data used in the model are based on the results of the 1972 and 1982 inventories.
It is envisaged that only the productive forests in the PEE and Stateland Forests (STF) are expected to produce timber. The productive PFE consists of primary forests (PRF) and partially harvested forests (PH). The latter is further divided into forests harvested before 1971 (PHi) and those harvested after 1971 (P1112), to recognize the higher timber volume due to growth over a longer period in the older, PHi management class. The management classes specified in this study are divided into four categories, i.e., PRF, PHi, P112, and STE Summary of the various categories of forests are depicted in Table 11. 60
Figure 5. A simplified diagram for a management planning model for loggingoperations in the hiliforest of Malaysia. Source: Yusuf (1987). 61
Table 11. Forest management area as of December 1980 in Terengganu
Forest Category Management Class Area ('000 ha
Forested area 580.5
PFE 577.3 (i) Productive 492.4 Primary PRF 247.0 Partially Harvested PH 245.4
-before 1971 PHi 108.6
-afterl97l PH2 136.8
(ii) Unproductive 84.9
(iii) Stateland Forests STF 3.3 62
The total gross volume of all forest species 45 cm dbh and larger is summarized in Tables 8a,8b,8c, and 8d. The net potential volume to be for the total forested land in the study area excluding National Park and Wildlife Sanctuary is estimated to be 30,968,000 m"3 for all forest tree species 45 cm dbh and larger (National Forest Inventory for the state of Terengganu, 1982).
The volume yield per hactare. was estimated separately for the existing forests and for the regenerated forests. The existing PRF was assumed to yield 79 mA3/ha. The existing stand in the PHi was assumed to yield 49 m"3/ha if it was harvested in the first decade and 77 m"3/ha if harvested in the following decade. The yields per ha for the various management units were estimated from the standing volumes recorded in the 1972 and 1982 forest inventories. As suggested by Yusuf (1987), the yield from the PRF was derived from average timber volumes in the Superior, Good and Medium forests weighted by their respective areas. The yields from the partially harvested forests (PHi and PH2) were calculated by averaging the timber volumes in the lightly harvested (after 1966) and heavily harvested (before 1966) forests and included the estimated growth in standing volumes. 63
The gross marketable volumes in the forests of average site are tabulated in Table 12. Net commercial volume was estimated by deducting allowances for defects and logging waste from these gross marketable volumes. The deduction is 40 percent for trees less than 60 cm dbh and 30 percent for trees above 60 cm dbh. These reduction factors were derived from the SMS (Yusuf, 1987). Marketable species comprised all of the species listed as fully marketable and partially marketable in the 1982 forest inventory (Appendix 4). It was assumed that tree species which were partially marketable or having future potential in 1972 are currently accepted by the timber industry. The yield of 79 m"3/ha from the primary forest (PRF) was obtained by summing 70 percent of 84 m"3/ha representing marketable species greater than 61 cm dbh and 60 percent of 34 m"3/ha (118-84) in the 46 to 61 dbh classes. Similarly the yield of 49 mA3/ha from the PHi was obtained by summing 70 percent of 44 mA3/ha for trees greater than 61 cm dbh and 60 percent of the 29 m"3/ha (74-45) in the 46 to 61 cm dbh classes. The 72 m"3/ha yield from the partially harvested forests at age 30 years was the result of the volume growth in trees greater than 45 cm dbh and the volume ingrowth from the next lower, 30 to 45 cm, dbh class. The yield of PHi was calculated by adding 20 percent per decade to the existing gross volume in each dbh class and also by including the volume ingrowth due to smaller trees growing into the minimum dbh class.
The partially harvested forests were assumed to yield the same volume as the primary forests 40 years after their last harvests. By then the forest stands were assumed to be crowded and the basal area increment had reached a plateau, as hypothesized by Dawkins (1958), Baur (1968) and evaluated for Peninsular Malaysian conditions by 64
Table 12. Average Gross Volume of Average Site For All Forest Types in Terengganu.
Average Gross Volume at indicated Forest category Lower Diameter Limit (mA3/ha
15cm 30cm 46cm 61cm
(a)Primary Forests All species 300 179 121 86 Marketable species 180 173 118 84
(b)Partially Harvested Forests All species 210 113 77 47 Marketable species 120 105 74 45
Source: Derived from National Forest Inventory of Peninsular Malaysia, 1982. 65
Yusuf (1987). Therefore, the yield was not expected to surpass the yield of 79 m"3/ha from the primary forests which can be considered as the yield corresponding to the plateau of the basal area increment. The yields from the regenerated forests were derived from stocking levels (stems/ha) for an average site and by applying the previously discussed estimates and assumptions.
Planning Horizon The time period considered in the planning model was 120 years, consistent with the suggestion that an acceptable degree of control and regulation could generally be achieved by spanning twice the length of the rotation specified in the model (Navon, 1971; Clutter, 1978; Leuschner, 1984; Yusuf, 1987). The planning horizon is divided into 12 ten-year (decade) periods. Management Objectives
The primary management goal is to maximize state government revenue from forest operations and activities with watershed, perpetuity, and other related management constraints. The rate of Royalty Premium and Development Cess Fund charges levied were those listed under the Rules of the National Forest Enactment (Amendments) of Terengganu, 1986. For the purpose of planning, the adopted figures were M$7.30/m"3
(US$2.70/m"3 with an exchange rate of US$1.00 equals M$2.70) for the Royalty rate,
M$3.50/m" (US$1.30/m"3) for the Premium rate and M$2.70/mA3 (US$1.00/m"3) for the Development Cess Fund. Thus, on the average a m"3 of log was assumed to provide M$13.50 (US$5.00) to the revenue of the State Government. A discount rate of 10 percent per annum was used as an approximation of the current interest rate in Malaysia. This rate has also been used for planning and evaluating public sector projects in Malaysia (Lockman, 1977 and Yusuf, 1987). 66
Management choices and alternatives The SMS is the selective cutting employed in the model with felling cycles of 30, 40 and 50 years. The liquidation policy adopted in the model specified that the existing stands of the PRF are to be harvested within the first three ten-year periods, and the existing older partially harvested forests, PHi, within the first four periods. The existing younger partially harvested forests, PH2, are to be harvested from the third to the fifth periods, after the older partially harvested forests have been harvested. From experience in forest management in Peninsular Malaysia, which is specifically being adopted in Terengganu, several alternative cutting cycles were specified for all management units in the PFE. The PRF areas could be harvested every 30 or 40 years and PHi and PH2 every 30, 40 or 50 years respectively depending on the scenario. A 30-year cutting cycle has been adopted in Terengganu since 1979. Harvest Control and Regulation Management Constraints A lower bound, used as a sequential constraint, was adopted for the six ten-year conversion periods. Each periodic harvest should be equal to or greater than 90 percent of the previous periodic harvest. In other words, the harvest volume in any period should not decrease more than 10 percent from the harvest volume in the preceding period. The first periodic harvest should be at least 90 percent of the (197 1-1980) harvest of 700,000 mA3. As it is now, Terengganu is procuring logs from other neighboring statesor sources to maintain the timber requirements of its already saturated primary wood-based industry. Thus, a gradual decline of 10 percent per decade will allow the timber industry to adjust and plan for the future needs. As for the remaining six decades or post-conversion APPENDICES 103
Appendix 1
SPECIFICATION FOR FOREST ROADS
IN PENINSULAR MALAYSIA 104
TERMINOLOGY
ROAD SHOULDER: Portion of road between the outer edge of the pavement and the inner edge of the ditch or slope.
ROAD FORMATION: Total width of roadway which includes both the width of the pavement and the width of the two shoulders on either side. C.B.R.: Abbreviation for California Bearing Ratio. It is a penetration test for the evaluation of subgrade strength based on the load required to cause a plunger of 1925 mmA2 in area to penetrate the specimen of at the rate of 1.25 mm per minute. The measurement can be taken either immediately after compaction of the sample in a mould or after soaking the compacted sample for 4 days.
SUBGRADE: Compacted ground on which the pavement rests and to which the entire load of the structure as well as the traffic plying on the surface above is ultimately transferred.
RIGHT OF WAY: Total width of cleared area for the road construction.
DESIGN SPEED: The speed used for design of road, determined by the physical features of a road way in relation to vehicle operation.
BRANCH ROAD: Road that branches out from the main road to serve the interior parts of the operation area.
SPUR ROAD: Temporary track which enables access to work area. APPROACH ROAD: Permanent road leading the operation area. MAIN ROAD: Major road within the operation area, where the minor roads branch out.
PASSING SIGHT DISTANCE: Distance sufficient to allowa vehicle to overtake another vehicle from opposite direction.
NON-PASSING SIGHT DISTANCE: Distance sufficient for the driver to stop the vehicle before collision with an obstructing object ahead. RADIUS OF CURVE: Radius of curve at the horizontal alignment.
OPERATION AREA: Area where harvesting and/or silvicultural activitiesare in operation.
CONCESSION AREA: Area to be logged under one permitj licence.
ADVERSE GRADIENT: Gradient of a climbing or ascending road denoted usually by a positive sign (+). 105
FAVORABLE GRADIENT: Downslope or descending gradient denoted usually by a negative sign (-).
CARRIAGEWAY: The width of the part of the road on which the traffic runs. SIDE DITCH: Drainage channel along the side of road.
SUPERINTENDING OFFICER: Officer named in the agreement to supervise the project. Abbreviated by the term S.0. PAVEMENT: Layers of metal or laterite that form the road surface. BUFFER ZONE: An undisturbed strip of land with natural vegetation. Also known as filter strip. 106
ROAD CLASSIFICATION AND STANDARDS
1W S 11 ID 'p S.s psbik.si.,.eis 1bS._ J 1105 .' dIvp .'U.. .d .l. .fhi.1...fhi .1.. .fhi St. .' .1.. batik S bsffk hi bItfkI Is Is ip.. Is gpr,g5 I. ad. Nad. pug. pug. Cw'Isp.g S..' S.il i 11..'. 1 $I.l. 1..
Ipipsid s0i,A 30l7P 2SWs K. II. 16. 30. 1105 E Nuts p.,'., 560. 15. I,.. t.. If 70. IS. 1st,] Csi 0.5 . LI. 1. 1. 11T15I.i tb lzU 1.20 La-... fr.mt 5% Si - 10% 12% tl$i3 (..i..)F.,sirèl. 7% 121 15% 20% RI,.st I.1 s.,b If slips 1. 3K. Ix. 60. SlOt If Pg 30. 20. 15. 12. UssiFiristtsa S. 7. S. 4. a VIb 6. S. 6. 3. 150. 1K. . 'It..'.' 5.5.1fr turd 11w
,s.4sift.. 1.5. 1. 1.5. 0.5.
1s30 b30 1:20 (prêsltc) t.bdght) 1.5. 1.5. 1. 1. Si as 0gb 0.5. 0.5. 1.3. 0.3. (1.,1vIts. S.d fr.d1.t 2% 2% 2% 2%
7u'v.la)15% is' is'
Tu'v.l. (55% 1,1 ti. is' 1:1 sit Flat..sd is? is? Id is? $Iè$hps *.ft SM 1.3 is' a..d SM ti is' is' S.sl 1:1k 1:15 til nil ti, S.c 1:115 I sI$ I :115 IsI$ SM.. Ir 3 b I pI b I p.. 1 . Dhs.h. 55* 1 5. a It 5.s 1
I.."., 22 b 22 22 b 22 tu I,". Its. P1db 6. 6. 3.5. 3.5 a 22 ba 22 22 22 b.i. Ci1iut sit,]C.r.55 sit,] 7,.. Lii
T1stu 7l.b.. -... *i..r.tu isists.t *.r.tu s..f$. Cr,*s.OsI isla 107
ROAD CONSTRUCTION
1. ALIGNMENT:
All roads shall be constructed in accordance with the alignment as shown in the drawing and/or as demarcated on the site. No deviation from the alignment is permitted unless prior approval has been obtained from the S.O. The alignment shall as far as possible be kept as far away from natural streams and rivers. A buffer zone shall be provided between a road and a stream. Width of Buffer Zone (m) = {7.6m + (0.6m * % of slope)}; with a minimum of 20 m.
2. SiTE CLEARING:
All trees and bushes within the right of way shall be cut and all stumps on the road formation and side slopes shall unless otherwise directed, be grubbed up and removed to a suitable place of deposit. All holes resulted from grubbing shall be filled and rammed solid with approved materials. All organic matter or other top soil shall be excavated and disposed as directed by the S.O. All trees larger than 115 mm in diameter within 1.5 m from the road shoulder edge on either side shall be felled. All trees within the right of way which give shade to the road at any time of the day shall be felled, regardless of diameters. These trees will be marked by the State Forestry Department.
3. ROCK BLASTING:
Rock blasting work as and when directed by the S.O. shall be made withproper employment of competent and skilled workmen, by the contractor/logger at his own costs and risks.
4. EXCAVATION:
Excavation to the required level shall be done and the formation shall be rolled and compacted until no further movement is observed and to the satisfaction of the S.0. The surface shall be graded to a crossfall as specified. 108
5. EMBARKMENT:
In cases where subgrade is a fill, filling shall be done only after the top soil has been removed. Only approved material from the excavation and borrow pits shall be used for filling. The fill material shall be deposited in layers not exceeding 230 mm thick and compacted with 16 passes of a 6 tonne roller or other approved means. The surface shall be graded to a crossfall as specified.
6. SUBGRADE: All subgrade shall be well trimmed, cleared, and graded. It shall be compacted with a 6 tonne roller or other approved means and kept free from mud and water at all times. All tree stumps, logs, and other debris within the subgrade width shall be removed. Under on circumstances shall any of the mentioned items be permitted to be buried in the subgrade. All organic matter or top soil shall be excavated and disposed off as directed by theS.O. All material for filling of subgrade shall be of good quality and free from all organic matter.
All subgrade are recommended to rest on cuttings. The compacted subgrade shall have a C.B.R. of not less than 15 percent.
7. PAVEMENT:
Metal and laterite shall be laid as pavement where specified. The paving materials shall be spread evenly in layers and compacted by at least 8 passes of a 6 tonne roller until no further movement of metal or laterite is observed. The pavement shall finally be graded to a specified camber. All laterite to be used for pavement shall be good quality and shall consist of 60 percent to 80 percent stone.
Crushed granite used for road construction shall be angular in shape and form, clean and free from decomposed rock, clay or organic matter.
8. GRADE:
Any grade greater than the one specified in the "Road Classification and Standards Table" shall be approved by the 5.0., in any case only limited to a continuous stretch not more than 60 m.
9. CAMBER:
Parabolic camber with an average crossfall of 1:30 shall be provided on all class I and class II roads. Straight camber with an average of 1:25 and 1:20 sloping towards one side of the road shall be provided on all class Ill and class IV roads. 109
10.CURVATURE: In curves, the camber shall be substituted by superelevation on the outer side of the curve. Generally, a maximum superelevation of 1:10 is recommended.
11.SIGHTDISTANCE: Distance greater than or equal to the minimum non-passing sight distance shall be provided on all intersections, vertical and horizontal curves. Passing sight distance on dual lane forest roads shall be provided as specified.
12. CURVE WIDENING: The pavement and subgrade shall be widened on the inside of the curve according to the formula below:
Additional Width (m) = 37.21
Radius of Curvature (m) Curves with radii exceeding 135 m require no widening.
13.TURN-OUT: All turn-outs shall be constructed in accordance with the specification pertaining to subgrade preparation. 14. ROAD SHOULDER:
Road shoulders shall be levelled at an average of 5 percent sloping away from the site of the pavement.
15.SIDE SLOPE:
All side slopes shall be cut as specified in the "Road Classification and Standards Table" according to the type of soil involved. Under normal conditions, all side slopes on embankment shall not be greater than 1:1.5.
16.TURFING:
When specified, all banks shall be close turfed. All turfs shall be 230mm square and held in place with wooden pegs of diameter 25 mm and length 225 mm. Black earth 50 mm thick shall be spread on all bank before turfing. 110
17. ROAD FURMTURE:
Road furniture such as distance markers, safety guard rails, sign boards, etc. shall be provided when specified. 111
DRAINAGE
1. DRAINAGE SYSTEM: Proper drainage system shall be provided as specified.
2. DITCH:
Side ditches shall be constructed along the entire length of road. The ditch gradients and discharge points shall be determined and located by the S.O. Side ditches shall be constructed with side slopes of 1:1.5 and a uniform flow gradient of at least 2 percent.
3. SURFACE CROSS-DRAIN:
Surface cross-drain shall constructed as shown in the drawings and as specified. Final locations shall be determined on site by the S.O. All timber surface cross-drain shall be of heavy hardwood or treated medium hardwood as classified under Malayan Grading Rules (1968).
4. CULVERT:
Culverts shall be precast reinforced spun concrete pipes jointed with precast concrete collars in cement mortar 1:3 laid on reinforced concrete bed of 1:2:4 mix, 150 mm thick or as directed by the S.O. The minimum diameter of such concrete culverts used shall be 450 mm Other approved types of culverts may be used when directed. Hollow logs as allowed by the S.O. shall be at least 300 mm diameter all through.
The location, spacing, and size of the culverts shall be as directed by the S.O. Placement of culverts:
Horizontal placement from the perpendicular of the road shall be 10 degrees.
Culverts shall be placed to a fall of 2 percent to 6 percent. The invert level of culverts shall coincide with the bed level.
The inlet opening for any culvert shall be extended at least 75mm but not more than 150 mm from the side slope. 112
The outlet opening for any culvert shall be extended at least 0.5 m from side slope.
Rock rip-rap or splash span shall placed at the outlet end of the culvert discharging water on to filled or cut slopes.
(1)Culverts for stream crossings:
Concrete or other approved culverts shall be used for all stream crossings. Culverts shall be placed to follow the alignment of the stream flow. All fill material used shall be free from organic matter or rock.
All fill material used shall be compacted in layers not exceeding 150mm. All back filling shall be well compacted to a minimum depth of 0.6m.
5. WATER-BARS:
In high hazard watershed, earth bunds functioning as water bars of minimum 1 m high shall be provided along the carriageway immediately after the completion of logging activities, to divert surface runoff into the forest. The spacing of water bars shall be as follows:
Road gradient Spacing 0-10% 60 m 11 - 15 % 30 m 16-20% 15m 113
BRIDGES
CONSTRUCTION:
Bridges shall be constructed as shown in the drawings and as specified. Final locations and dimensions shall be determined on site by the S.O. All timber bridges shall be constructed with logs, poles and bulks of naturally durable heavy hardwood as classified under the Malayan Grading Rules (1968). DECKING:
Decking for timber bridges shall be of heavy hardwood sawn timber of dimensions 75 mm * 150 mm or 100 mm * 230 mm with a 150 mm spacing provided between each decking member unless otherwise specified. RUNNING BOARD:
Running boards shall be of heavy hardwood sawn timber. Dimensions of running boards shall be 75 mm * 150 mm with a 50 mm spacing provided between each member unless otherwise specified. WIDTH:
The minimum width for bridge shall be 3.5 m. ABUTMENT:
The height and type of bridge abutment shall be determined by the S.O. PILING:
Where piles are required for bridge construction the pile size and piling procedures shall be determined by the S.O. APPROACH AND EXiT:
The approach and exit gradient for the access road before and after the bridge shall not exceed 5 percent.
The approach to the bridge shall remain straight fora minimum continuous stretch of 20 m. 114
ROAD INSPECTION AND MAINTENANCE
1. INSPECTION:
The road must be allowed to season for a minimum period of two weeks before logging operations begin. The actual time will be determined by the S.O. after a site inspection of the completed road. A final inspection shall take place any time after the seasoning period. If any defects relating to the road are found, the contractor/logger shall make good those defects.
Logging operations shall not be allowed to start until the S.O. is satisfied that the road is built to specification.
If any time logging operation and road construction are in different compartments/blocks of the same concession area and if the road is not built to specification, the S.O. shall be empowered to stop all logging operations within the concession area.
2. MAINTENANCE:
The logger/contractor shall during the validity period of the logging/road permit, maintain the roads, including drains and culverts to the satisfaction of the S.0.
The pavement shall be kept free from standing water, pot holes and other defects at all time.
For this purpose, the contractor/logger shall at his own expense employa maintenance team to carry out the road maintenance work. 115
DRAWINGS TYPICAL TOTAL FILL CROSS SECTION
vv w,,/w Nqr
Note: A - RIGHT OF WAY B - ROAD FORMATION C - ROAD SHOULDER D - PAVEMENT E - SIDE SLOPE F-TURFJNG G - SIDE DITCH H - ORIGINAL GROUND LEVEL I- CAMBER 116
TYPICAL TOTAL CUT CROSS SECTION
Note: A -1UGHT OF WAY B -O1UGINAL GROUND LEVEL C -ROAD FORMATION D -PAVEMENT E -ROAD SHOULDER F-SIDE SLOPE G -TURFING CAMBER SIDE DITCH 117
PLAN VIEW OF A TYPICAL CULVERT
Note: A -ROCK RIP RAP B -CULVERT C -ROAD SHOULDER D -PAVEMENT SIDE DITCH SUMP G -ROAD PERPENDICULAR 118
TYPICAL CROSS PROFILE OF CULVERT
:-
"' 'Y/ "'
Note: A - PAVEMENT B - ROAD SHOULDER C-SUMP D - FOUNDATION BASE E-SCREED F - HARDCORE G - ROCK RTP RAP H- BED SLOPE 119
PLAN VIEW OF A TYPICAL TIMBER SURFACE CROSS-DRAIN
Note: A - SURFACE CROSS-DRAIN B - ROAD SHOULDER C - PAVEMENT D - ROAD PERPENDICULAR E - SIDE DITCH F - DIRECTION OF FLOW G - RUNNTNG BOARD 120
CROSS SECTION OF A TYPICAL TIMBER SURFACE CROSS DRAINS
Note: A - RUNNING BOARD B - PAVEMENT \'4_- rw..'' 122
Appendix 3
MAP OF FOREST TYPES OF TERENOGANU 'oV.oy .oii Bk.Ia I:7b0.000 s m 70 40 ID o -
PAv
TU ANU
06OO U LEGEND
Suoerj.or Natural FOreEts Good Natural Forests $e6iu Natural Forests
$atural Peat Swa Forests fiRDisturbed Forests L000ed-0V5r Forests =Loaged-oVeV NaturalPeat Swa70p Forests poor Forests
$ontafle Forests
River
0(00 U 123
Appendix 4
THE LIST OF COMMERCIAL TREE SPECIES IN MALAYSIA (1978)
CODE DIPTEROCARPS COMMON NAME
1 Meranti group
112 Dark Red Meranti Seraya, ITill Meranti, Nemesu (Shorea pauciflora), Red Sengkawang (Shorea palembanica) 113 Light Red Meranti Meranti rambai daun (Shorea acuminata), Meranti batu (Shorea dasyphylla), Meranti daun besar, Meranti tembaga (Shore leprosula), Meranti langgung (Shorea lepidota), Meranti pepijat (Shorea johorensis), Meranti kepong (Shorea ovalis), Meranti sarang punai (Shorea parvifolia), Meranti paya (Shorea platycarpa), Meranti bunga (Shorea albida), Meranti tengkawang air (Shorea palembanica).
114 White Meranit Species listed in "Pocket checklist of timber trees" such as Meranti paang (Shorea bracteolata). 115 Yellow Meranti Species listed in "Pocket checklist of timber trees". 116 Meranti melantal Melantai species.
CODE NON-MERANTI COMMON NAME Light hardwoods
124 Mersawa Mersawa (Anisoptera species)
126 Merawan Merawan (Hopea species) and Mata kucing species listed as light hardwoods in 'Pocket checklist of timber Irees". 127 Gerutu Gerutu (Parashorea species) 124
Medium hardwoods 120 Keruing with oil Keruing (Dipterocarpus species) (22 species, other than listed below)
123 Oily Keruing Red Keruing, Sol Keruing, Keruing kertas, Keruing gombang, Keruing gondol, Keruing bulu and Keruing ternek.
122 Kapur Kapur (Dryobalanops species) and Keladan (Droyobalanops oblongifolia) Heavy hardwoods
121 Balau Balau (Shorea species), Sengkawang air (Shorea sumatrana)
125 Chengal Chengal (Balanocarpus heimii)species 128 Red Balau Red Sea Dipterocarp and Membatu (Shorea guiso)
129 Others Giam and Resak (Cotylelobium and Vatica species)
2 NON-DIPTEROCARPS
Light hardwoods fully marketable
211 Sesendok Sesendok (Endospermum species)
212 Macang Macang (Mangifera species), Mangga, Lanjut and Rawa species
213 Kembang semangkokKembang semangkok (Scaphium species) 214 Kedondong Kedondong (Parishia species)
215 Sepetir Sepetir (Sindora species)
217 Nyatoh Nyatoh (Sapotaceae family) and Taban merah species 218 Jeluntong Jelutong (Dyera species)
219 Melawis Melawis (Gonystylus species) and Ramin species 221 Bintangor Bintangor (Calophyllum species)
222 Geronggang Geronggang (Cratoxylem species)
223 Terentang Terentang (Campnosperma species) 125
224 Kungkur Kungkur (Pithecellobium species) and Kerdas species 225 Durian Durian (Durio species), Punggai, and Bengang species 226 Mempisang Mempisang (Anonaceae family) and Jangkang species 227 Pelong Pelong (Pentaspadon species) Light hardwoods partially marketable
231 Penarahan Penarahan (Myristicaceae family) 232 Ara Ara (Ficus species)
233 Melunak Melunak (Pentace species) 234 Kelampayan Kelampayan (Anthocepahlus chinensis) 235 Sentang Sentang (Meliaceae family) 236 Temp Terap (Moraceae family), Ara berteh bukit, Ara berteh paya, Ipoh. 238 Kayu Arang Kayu Arang (Diospyros species) 252 Medang Medang (Luraceae family), Teja-Teja 239 Others Pulal, Petai, Ludai, Gerok, Perupok, Mahang, Senkuang, Antoi, Dedali, Mengkundur, Sentul, Kasah. Medium hardwoods fully marketable
241 Kempas Kempas (K000mpassia malaccensis) 242 Keledang Keledang (Artocarpus species), Tampang, Cempedak, Nangka, Sukun, Bangkong, Temponek. 243 Mata Ulat Mata Ulat (Kokoona species)
244 Punah Punah (Tetramerista species)
245 Simpoh Simpoh (Dillenia species) 251 Tualang Tualang (Koompassia excelsa)
216 Mengkulang Mengkulang (Heritiera species) Medium hardwoods partially marketable
255 Berangan Berangan species 126
261 Rengas Rengas (Anarcardiaceae family) 262 Mempening Mempening (Fagaceae family) 263 Petaling Petaling (Ochanostachys amentacea)
264 Kulim Kulim (Olacaceae family) 265 Minyak berok Minyak berok species 266 Kasai Kasai (Pometia species) 267 Merpauh Merpauh (Swintonia species)
268 Merbatu Merbatu (Parinari species) 269 Others Kelat, Perah, Jelawai, Derum, Bakau species Heavy hardwoods fully marketable
271 Kekatong Kekatong (Cynometra species) 272 Merbau Merbau (Instia species)
281 Keranji Keranji (Dialium species) Heavy hardwoods partially marketable
282 Tembusu Tembusu (Fagraea species) 283 Pauh Kijang Pauh Kijang (Jrvingia malayana)
284 Others Rambutan, Lotong, Redan, Penaga, Leban, Pulasan.
3 CONIFER
311 Damarminyak Damar minyak (Agathis bomeensis) and Kauri 312 Pod Podo (Podocarpus species) 411 Miscellaneous Lesser known species listed in 'Pocket check list". 127
Appendix 5
CLASSIFICATION OF LAND FOR FORESTRY USE IN MALAYSIA
CLASS DESCRIPTION SUFABILITY
1 Superior Land with none or only minor Suitable for sustained high yield constraint(s) for production of management under natural timber and other forest products.regeneration with wide range of Generally undulating with an species and plantation with average slope of less than 20 fast-growing or high value species. degrees and easy access.
2 Good Land with moderate constraint(s)Suitable for sustained yield for production of timber and management under natural other forest products. Generallyregeneration with or without undulating to hilly with averageenrichment planting. slope of 20 degrees to 30 degrees and moderately difficult access.
3 Marginal Land with serious constraint(s) Suitable for sustained yield for production of timber and management under natural other forest products. Generallyregeneration with retention of hilly with an average slope of 30adequate residual stocking. degrees to 40 degrees and difficult access.
4 Restrictive Land with limitation(s) for Suitable only for restricted production of timber and other management under natural forest products. Generally regeneration with or without lowlying and subject to enrichment planting. inundation; mainly mangrove and inland swamps. 128
5 Conservation Land with a vital role in the Essential for safe-guarding protection of environment and environment, soil, water, flora, fauna, the conservation of ecosystem. and other natural resources, Generally hilly to mountainous especially in critical watersheds and with steep and unstable slopes unique habitats or sites. but includes lowlying to undulating terrain.
6 Poor Land with serious limitation(s) Currently not suitable for production for production of timber and management but essential for other forest products. Generallymaintenance and ecological balance. very steep slopes and mountainous terrain with difficult access but includes naturally poor mangrove and inland swamps. 129
Appendix 6
SLOPE MAP USED IN THE STUDY 130
Appendix 7
DETACHED COEFFICIENT MATRIX OF THE TERENGGANU MODEL Apper.di 7 0CM 0CM 0CM 0CM 0CM 0CM 0CM DCII DCII 0CM 0CM 0CM 0CM 0CM PRFS2PRFS1ROUS LP1 LP2 LP LP1 LP5 LP6 f_P? LP8 LPI LP1u LP11 LP12 L1S PP11S1P.1 1 PP11521: STF2STFPH2PHiPRFR2FP.FR1 1 1 YL6VL5I.L1VL3VL2YL I -1 -1 -1 -1 -1 -1 0.0560.079 0.00.0T VL12VL1OI/L9VL8VL? L11 -1 -1 -1 0.056 0.0Sf PL1PLPL3PL2 1 1 1 1 -1 PLPL6PL5 7 1 1 1 1 PLI1PL9PL1OPL8 1 1 1 1 CL7LtILPL12LPILft 1 1 -1.1-0.9 -6 CU9CL9CU8CLCU? --0.9-1.1-0.9 CL11CubCL1O 1 -0.9-1.1 SL5L2CU12CL12CUll 1 1.1 -o. 1 -1.1-0.9 SED1SL&SLS5L4 -0.9 -0.9 -0.9 1 MAXSED5SED45E035E02 0.6? 21 II 0CM 0CM 0CM 0CM CDCII DL liii N S 0CM 0CM DCII 0CM 0CM 0CM DCII 0CM 0CM DCII DCII ocri i1S12 PP11S2F2 PP12S1R1 FP12S2F1 PPl2S1I2 FF12S22 1Ppiasip.i PP1BS2R1 PP13S1F2 PP1352R2 FP21S1R1 PP21521 PF21S12 FP2152f2 PP22S1P.1 FP2252R11 PF22S12. PP22 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 0.079 1 0.079 1 1 1 1 1 1 1 1 1 0.079 1 0.0?9 1 0.079 1 0.079 1 1 1 1 0.056 0.056 0.0560,079 0.0560.079 0.0560.079 0.0560.079 0.0560.079 0.0560.079 0.05600?9 0.0560.079 0.07? 0.07? 0.0?? 0.07? 0.07?0.079 0.0770.079 0.0??0.079 0I) 0.0560056 0.056 0.056 0.056 0.056 0.056 0.056 0.056 0.056 0.056 0.07? 0.0?? 0.0?? 0.0?? (1,077 0.0?? 0.07? 0
2.5 7.5 1 1 23 2.5 7.5 5 1 0831.6? 2.5 5 0.3306? 23 1 0.831.6? 2.5 2.57.5 5 067 1 23 1 0.831.67 2.5 2.57.5 5 O.330.6? 1 0.i31.67 2.5 0.330.6? 231 0.831.67 2.5 I I I I I I I I I I I S2.S .L91 t 9O C
SUO 6.00 o-ct OO .L40C' 950_U 9500 950950-U C1 9OU d..00 200 00 d400 .L0U 0_0 L0_0 oo 6.L009500 0U -tU0 950U90Cf 6.L002400 L00 00 6.0O 0O I I I I 6I00I I I I IE.I'OU I I I I60U I .0O 500 1I-1 I I I I I £I?I-I uo IH uao ?TI uo IEII-1 wio uao eIH 1.130 1H 1.130 I1H U30 IIH W30 IIH .130 TIH 1.110 IIII- 1.130 S.2rJc 1.110 I 11S2dd 1.130 S?dd 1JISdd 1.130 1.130 ocri ocr ocri ocri ocul ocri acri ocri ocul Dcli ocui ocr 12:11 11215 11223 11221 11225 11233 11231 11235 STFI STF2 R == 213HS '39 1 = 100.6 2.3 01 .079 0.079 0.072 0.1:179 0.079 0.072 0.079 0.079 0.09 0O56 = 0o .055 0.0550.06 0.07? 0.0??0.077 0.0??0.0?? 0.079 0.079 0.079 = 00 >= 7 >= 07 >= = 00 >= 00 >= 07 0.03 0.53 <=>= 1150 00