eTHEKWINI OUTER WEST CORRIDOR STUDY
MUNICIPALITY AND LOCAL AREA PLANS
eTHEKWINI MUNICIPALITY
OUTER WEST CORRIDOR STUDY AND CATO RIDGE LOCAL AREA PLANS
GRAHAM MULLER ASSOCIATES CONSORTIUM
Biodiversity Situational study
Compiled by
GRAHAM MULLER ASSOCIATES CONSORTIUM
eTHEKWINI OUTER WEST CORRIDOR STUDY
MUNICIPALITY AND LOCAL AREA PLANS
TABLE OF CONTENTS
TABLE OF CONTENTS ...... II LIST OF FIGURES ...... I LIST OF TABLES ...... II 1. INTRODUCTION ...... 1 1.1 Background ...... 1 1.2 Objectives ...... 1 1.3 Study area ...... 1 1.4 Approach ...... 3 2. OVERVIEW OF CATCHMENTS ...... 5 2.1 Catchment 1: Mshwati River ...... 6 2.1.1 Land uses ...... 6 2.1.2 Natural open spaces ...... 6 2.1.3 Catchment condition ...... 7 2.1.4 Drivers and pressures ...... 7 2.2 Catchment 2: Mngcweni River ...... 7 2.2.1 Land uses ...... 7 2.2.2 Natural open spaces ...... 8 2.2.3 Catchment condition ...... 8 2.2.4 Drivers and pressures ...... 9 2.3 Catchment 3: Sikelekehleni River ...... 10 2.3.1 Land uses ...... 10 2.3.2 Natural open spaces ...... 11 2.3.3 Catchment condition ...... 11 2.3.4 Drivers and pressures ...... 11 2.4 Catchment 4: Mlazi River ...... 11 2.4.1 Land uses ...... 11 2.4.2 Natural open spaces ...... 12 2.4.3 Catchment condition ...... 12 2.4.3 Drivers and pressures ...... 13 2.5 Catchment 5: Sterkspruit ...... 13 2.5.1 Land uses ...... 13 2.5.2 Natural open spaces ...... 14 2.5.3 Catchment condition ...... 14 2.5.4 Drivers and pressures ...... 15 2.6 Catchment 6: Wekeweke River ...... 15 2.6.1 Land uses ...... 15 2.6.2 Natural open spaces ...... 16 2.6.3 Catchment condition ...... 16 2.6.4 Drivers and pressures ...... 16
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2.7 Catchment 7: Umhlatuzana River ...... 17 2.7.1 Land uses ...... 17 2.7.2 Natural open spaces ...... 17 2.7.3 Catchment condition ...... 18 2.7.4 Drivers and pressures ...... 18 2.8 Summary of catchment condition ...... 18 2.8.1 Terrestrial environment ...... 18 2.8.2 Aquatic environment ...... 20 3. BIODIVERSITY ASSETS STATUS QUO ...... 22 3.1 Aquatic ecosystems ...... 22 3.1.1 Rivers and dams...... 22 3.1.2 Wetlands...... 23 3.2 Terrestrial ecosystems ...... 25 3.2.1 Vegetation types ...... 25 3.2.2. Natural habitat ...... 26 3.2.3 Important flora ...... 28 3.2.4 Important fauna ...... 29 3.3 Areas of conservation importance ...... 30 3.3.1 C-plan ...... 30 3.3.2 Metropolitan Open Space System ...... 31 3.3.3 Formally protected areas...... 32 3.4 Biodiversity hotspots ...... 33 3.4.1 Important plant communities ...... 33 3.4.2 Important biota (fauna and flora) ...... 35 4. WAY FORWARD ...... 36 4.1 Drivers and pressures ...... 36 4.2 Biodiversity information sources ...... 36 5. REFERENCES ...... 37
GRAHAM MULLER ASSOCIATES CONSORTIUM
eTHEKWINI OUTER WEST CORRIDOR STUDY
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LIST OF FIGURES
Figure 1 Site map showing the study area for the Outer West in relation to major rivers and urban areas ...... 3 Figure 2 Land cover map for the Mshwati Catchment (after DEAT and EKZNW, 2008) ...... 6 Figure 3 Land cover map for the Mngcweni Catchment (after DEAT and EKZNW, 2008) ...... 8 Figure 4 Land cover map for the Sikelekehleni Catchment (after DEAT and EKZNW, 2008) ...... 10 Figure 5 Land cover map for the Mlazi Catchment (after DEAT and EKZNW, 2008)...... 12 Figure 6 Land cover map for the Sterkspruit Catchment (after DEAT and EKZNW, 2008) ...... 14 Figure 7 Land cover map for the Wekeweke Catchment (after DEAT and EKZNW, 2008) ...... 16 Figure 8 Land cover map for the uMhlatuzana Catchment (after DEAT and EKZNW, 2008) ...... 17 Figure 9: Proportion of catchment areas that consist of natural habitat and the extent of these areas that are degraded and/or moderately/highly infested by alien plants ...... 19 Figure 10: Summary of habitat areas within the Outer West that are degraded and the proportion of habitats that are moderately/highly infested by alien plants ...... 20 Figure 11 Graphical summary of ecological status of respective catchments within the Outer West area. Grey areas indicate no data availability...... 21 Figure 12: Spatial network of rivers and major dams that drain the Outer West ...... 22 Figure 13: Spatial distribution of potential wetlands based on a topographical analysis ...... 24 Figure 14: Spatial distribution of the vegetation types throughout the Outer West (after Mucina and Rutherford, 2006) 26 Figure 15: Map of natural habitats that presently occur within the Outer West as obtained from the eThekwini District Municipality landcover classification ...... 27 Figure 16: C-plan data for the Outer West study area illustrating areas varying conservation importance (ranked according to irreplaceability) and which areas have been transformed...... 30 Figure 17: Spatial network of the D’MOSS within the Outer West study area ...... 31 Figure 18: Distribution of nature reserves and conservancies within the Outer West study area ...... 32 Figure 19: Spatial distribution of important plant communities as mapped during the interim sensitivity analysis ... 34 Figure 20:Spatial distribution of important biota (fauna and flora) as mapped during the interim sensitivity analysis ...... 35
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LIST OF TABLES
Table 1 Summarised River Health Status for the Mngcweni River upstream of the confluence with the uMngeni River (after Ethekwini State of Rivers Reports) ...... 9 Table 2 Summarised River Health Status for the Sikelekehleni River upstream of the confluence with the uMngeni River (after Ethekwini State of Rivers Reports) ...... 11 Table 3 Summarised River Health Status for the Mlazi River from sites upstream and downstream of the catchment area (after Ethekwini State of Rivers Reports) ...... 13 Table 4 Summarised River Health Status for the Sterkspruit from upstream and downstream sites (after Ethekwini State of Rivers Reports) ...... 15 Table 5 Summarised River Health Status for the uMhlatuzana River (after Ethekwini State of Rivers Reports) ...... 18 Table 6: Examples of goods and services provided by healthy rivers (after Meyer, 1997)...... 23 Table 7: Summary of the dominant vegetation types occurring within the Outer West (after Mucina and Rutherford, 2006) 25 Table 8: Summary of natural habitats present within the Outer West and their relative extents ...... 28
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1. INTRODUCTION
1.1 Background The primary purpose of this study was to establish the current status in terms of available information sources and data surrounding terrestrial and aquatic biodiversity components to spatially define the biodiversity assets of the Outer West. Outcomes from this study will then be used to inform the forthcoming project phases, namely, the Outer West corridor study and the Cato Ridge Local Area Plan (LAP). Based on the information and data available, areas of biodiversity importance will be provisionally determined to provide information with regards to the possible developmental constraints and opportunities for the Outer West, which may then potentially affect future development planning and management for the area. Any gaps encountered as part of data gathering will be highlighted with possible options for a way forward made clear.
1.2 Objectives The following objectives were therefore considered for the purpose of the spatial biodiversity study: Ensure that habitats supporting biodiversity, particularly rare and endangered species, are identified in order to be preserved and protected; Establish a network of corridors to facilitate biodiversity connectivity; Ensure that riverine (instream and riparian) areas are identified in order to be protected; Produce a biodiversity sensitivity map indicating areas of biodiversity significance; and Provide recommendations to ensure that important biodiversity areas are sufficiently preserved in order to allow for sustainable development opportunities.
The aforementioned objectives are not limited to this situational analysis and also refer to the corridor and LAP components of the project.
1.3 Study area The Outer West study area covers an area of approximately 328.5 km2 and is situated on the western most extent of the eThekwini District Municipality (Figure 1). This area therefore comprises several key catchments that fall within two regionally important secondary catchment systems, namely the uMngeni and Umlaas Catchments. The uMgeni river system Page 1 of 37
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MUNICIPALITY AND LOCAL AREA PLANS is more significant from a water resources perspective in that it provides the bulk water supply to the greater Pietermaritzburg/Durban area. Consequently, the uMngeni River has been impounded by four large dams (e.g. Midmar, Albert Falls, Nagle and Inanda Dams) all which play an integral role to the supply of potable water. The three northern-draining catchment systems (i.e. Mshwati, Mngcweni, and Sikelekehleni) enter the uMngeni River downstream of Nagle Dam and upstream of Inanda Dam. Majority of the southern-draining catchments of the Umlaas system enter into the Shongweni Dam before leaving the study area.
Given the extent that the study area covers, as well as the range of environmental conditions (topography, geology, hydrology, etc.), the Outer West has the potential to support a wide variety of biodiversity assets, including terrestrial fauna and flora and aquatic ecosystems. These assets are important for sustaining ecological and socio-economic elements, locally and regionally, through the goods and services that are generated as a result of complex ecological functioning.
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# Nagle Dam Table Mountain
M su n d u z e eni River R uMg i ve r ti Mshwa Inanda Dam Stream r e iv R i n e w S c ikel g ekeh n St leni M ream # Cato Ridge
U S m te h Hillcrest r l # ks a Kloof p tu r z # ui a t n a R Mpumalanga Wekeweke iv # e Stream r
Shongweni # Shongweni Dam Eston # Mlaz i River
N # Town Rive r Dam Stu dy are a eThe kw in i M un icipa lity
W E 8 0 8 16 Kilometers
S
Figure 1 Site map showing the study area for the Outer West in relation to major rivers and urban areas
1.4 Approach The following approaches will be employed in order to achieve the objective of defining the status quo for the project: Page 3 of 37
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The likely drivers and pressures affecting the biodiversity elements of the Outer West, particularly the aquatic systems, will be highlighted through interpretation of present land cover and land use activities. This is done on a catchment scale as it provides an integrated overview of impacts affecting each of the catchments thus enabling more strategic developmental planning and management in future. More specific impacts known to be having a significant effect on the catchments will also be discussed. To allow for an integrated understanding of the impacts to the catchments of the Outer West, river health information obtained during aquatic biomonitoring surveys conducted within the study area from 2004 to 2007 will be used to describe the present status of the aquatic environment highlighting any possible trends. In terms of the terrestrial environment, information defining habitat condition was obtained from the Systematic Conservation Plan which is in the process of being finalised by the eThekwini Municipality.
Available information and data will be sourced to spatially define the biodiversity assets of the Outer West following a desktop analytical approach. Information will cover both the terrestrial and aquatic environment to facilitate the process of determining areas of constraint and opportunity regarding future developmental potential. Specific biodiversity information will be sourced from previous specialist studies, relevant biodiversity databases, and literature so as to provide a detailed picture of valuable biodiversity features, specifically addressing the need for protecting and conserving threatened species. Spatially explicit maps will be used to define areas of biodiversity importance which may then facilitate future planning and development.
Depending of the availability of data for the study area, notable gaps in information sources that otherwise limit the ability of best defining important biodiversity areas of the Outer West will be highlighted with possible solutions provided to improve the integrity of mapping procedures.
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2. OVERVIEW OF CATCHMENTS Present land cover data provides useful information of the likely drivers and pressures affecting catchments. The land cover within the respective catchments was examined in terms of the key role that land cover plays in affecting various hydrological and ecological processes and other pressures within catchment areas. The current land cover for the catchments draining the Outer West was derived from a desktop GIS study using the land cover database developed by the Department of Environmental Affairs and Tourism (DEAT) and EKZNW for KwaZulu-Natal (DEAT and EKZNW, 2008). For each catchment, the percentage area of each land cover type was calculated and used to reflect the present land cover condition for the relevant catchments, as well as potential key drivers or pressures being exerted on the environment through modified land use. These data were useful in interpreting some of the biological responses observed in the rivers, as well as understanding some of the key pressures being exerted on these resources.
Details of habitat condition were obtained from the latest version of the eThekwini Municipality land cover database. The database provides categorised information regarding habitat degradation (good versus degraded) and alien plant infestation (low, moderate, and high infestation) within habitat areas. Confidence in this information is limited by the amount of verification that has been undertaken to date; only 23% of the natural habitat areas of the Outer West study area have been verified of which 66% is based on field-based verification studies. Nonetheless, the land cover database is useful in terms of gauging disturbances to various habitat types, namely forest, wetland, grassland, thicket, and woodland. At present, the eThekwini Municipality is in the process of developing a Systematic Conservation Plan, which will provide a greater level of detail for defining and conserving habitat areas than the Durban Metropolitan Open Space System (D’MOSS) approach currently adopted by the municipality.
Aquatic biomonitoring data obtained during the 2006 and 2007 eThekwini Municipality State of Rivers (SoR) surveys was summarised for those catchments sampled during the surveys. Additional data from smaller studies conducted during 2004 was also included. These studies are particularly useful for the context of this study as they were carried out to determine river health status according to various biological indicators. The usefulness of these indicators, particularly diatoms and aquatic macroinvertebrates, is that they provide an integrated understanding of catchment condition, especially land use impacts to the aquatic environment.
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2.1 Catchment 1: Mshwati River The Mshwati Catchment is approximately 37.7 km2 and drains into the Msunduze River approximately 20km upstream of the Msunduze/uMngeni confluence. This catchment is strategically important in that the upper catchment areas drain parts of the town of Cato Ridge.
2.1.1 Land uses
Rural dwellings (15%), urbanisation (8%), and subsistence agriculture (7%) are the dominant land uses within the Mshwati Catchment. The extent of these land uses, and other less s dominant land uses, is illustrated in Figure 2 below.
er Riv uze 2 und 1 Ms 3
5
4 6 7
Land cover Land cover Plantation Bushland
W etlands Grassland / bush clumps mix
Sugarcane Grassland
Mines and quarries Bare sand
Urban Degraded bushland
Golf courses Degraded grassland
Rural dwellings Old cultivated fields - bushland
Subsistence (rural) Smallholdings - grassland
Crops dryland Erosion
Crops irrigated Bare rock
Forest Roads
Dense bush Rivers and dams
Figure 2 Land cover map for the Mshwati Catchment (after DEAT and EKZNW, 2008)
2.1.2 Natural open spaces
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The natural areas are comprised mostly of grassland which account for approximately 36% of the catchment. Bushveld and grassland/bush clumps respectively make up 26 and 5% of the catchment.
2.1.3 Catchment condition
A significant proportion of the natural habitat areas are considered to be degraded, particularly forests, wetlands, and thickets. This is largely due to the extensive rural settlements that occur within this catchment and the intensive subsistence farming that is associated with these areas. As a result there has been a fair amount of soil erosion and alien plant infestation to the natural habitat areas.
Although no aquatic biomonitoring has been conducted for the Mshwati River, it is likely that the catchment condition will be no better than ‘fair’ due to the extensive urban and rural settlements situated within the centre of the of the catchment.
2.1.4 Drivers and pressures
The dominant drivers affecting this catchment are likely to be associated with formal and informal settlements that occur within the catchment. Potential sources of pollution from Cato Ridge may enter the tributaries and then into the Mshwati River.
2.2 Catchment 2: Mngcweni River
The Mngcweni Catchment is approximately 44.7 km2 and drains into the uMngeni River downstream of the Msunduze/uMngeni confluence.
2.2.1 Land uses
This catchment is dominated by urbanisation (16%), rural dwellings (13%) and subsistence agriculture (6%); the extent of these and other land uses is illustrated in Figure 3 below. Industrial activity exists in the upper reaches of the catchment.
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2 1 3 r ve Ri e uz nd su 5 M U m n g e n i 6 R 4 7 iv e r
Land cover Land cover Plantation Bushland
W etlands Grassland / bush clumps mix
Sugarcane Grassland
Mines and quarries Bare sand
Urban Degraded bushland
Golf courses Degraded grassland
Rural dwellings Old cultivated fields - bushland
Subsistence (rural) Smallholdings - grassland
Crops dryland Erosion
Crops irrigated Bare rock
Forest Roads
Dense bush Rivers and dams
Figure 3 Land cover map for the Mngcweni Catchment (after DEAT and EKZNW, 2008)
2.2.2 Natural open spaces
Majority of the Mngcweni Catchment is covered by bushveld, which makes up for approximately 38% of the area. The remaining natural open spaces comprise grassland (20%), grassland/bush clumps (3%) and forests (1%).
2.2.3 Catchment condition
The Mngcweni Catchment was considered defined with a ‘good’ ecostatus during the SoR surveys (Table 1). This was largely as a result of good scores being recorded from assessing aquatic macroinvertebrates and habitat integrity. However, the results from the diatom assessments indicated that the aquatic systems were in a ‘fair’ condition, a likely response to nutrient pollution generated within the catchment. Fortunately, the Mngcweni River is reasonably well buffered by large areas of natural vegetation and remains fairly protected due to the topography (i.e. deep valleys with limited access).
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Table 1 Summarised River Health Status for the Mngcweni River upstream of the confluence with the uMngeni River (after Ethekwini State of Rivers Reports)
Aquatic Inverts Habitat Integrity Diatoms Period Ecostatus SASS (SPI) ASPT Instream Riparian Score 2004 148 6.4 Nil Good Good Good 2006 146 6.08 Fair Good Good Good 2007 157 6.28 Fair Good Good Good
2.2.4 Drivers and pressures
The town of Cato Ridge occurs within the upper reaches of the catchment and it is likely that numerous impacts are generated from this area which will affect the Mngcweni Catchment, particularly as a result of operation by the Cato Ridge Abattoir, sewage works and various industries. Other impacts noted during the SoR surveys that are also a potential threat to this catchment included: Illegal artisanal sand mining activities; Illegal dumping into open areas and riparian zone; and Alien plant infestation to the riparian zone.
It was noted that the Mngcweni River may be exposed to significant contamination of heavy metals (e.g. mercury) as a result of industrial activity taking place in the catchment. This was highlighted by GroundTruth during an investigation of mercury contamination of fish within Nagle and Inanda Dams during 2008.
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2.3 Catchment 3: Sikelekehleni River
The Sikelekehleni Catchment is approximately 27.1 km2 and drains into the uMngeni River downstream of the confluence of the Mngcweni River with the uMngeni.
2.3.1 Land uses
In terms of land use, 14% of the Sikelekehleni Catchment constitutes rural dwellings, 7% urban, and 4% subsistence agriculture. A small portion of the catchment (3%) contains plantations, sugarcane, and small holdings.
U m g e n i R iv 2 e r 1 3
5
4 6 7
Land cover Land cover Plantation Bushland
W etlands Grassland / bush clumps mix
Sugarcane Grassland
Mines and quarries Bare sand
Urban Degraded bushland
Golf courses Degraded grassland
Rural dwellings Old cultivated fields - bushland
Subsistence (rural) Smallholdings - grassland
Crops dryland Erosion
Crops irrigated Bare rock
Forest Roads
Dense bush Rivers and dams
Figure 4 Land cover map for the Sikelekehleni Catchment (after DEAT and EKZNW, 2008)
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2.3.2 Natural open spaces Half of the Sikelekehleni Catchment is covered by bushveld. Grassland and forest make up 13 and 8% of the catchment respectively.
2.3.3 Catchment condition
The Sikelekehleni Catchment showed general signs of ecological degradation between 2004 and 2007 where ecostatus decreased from ‘fair’ to ‘poor’ (Table 2). The catchment is negatively affected by extensive and poorly managed sand mining operations, to the extent that sites were completely submerged. As a result, impacts have caused serious degradation to the riparian system. The severity of impacts from the sand mining was particularly obvious from the riparian and instream habitat assessments (Table 2).
Table 2 Summarised River Health Status for the Sikelekehleni River upstream of the confluence with the uMngeni River (after Ethekwini State of Rivers Reports)
Aquatic Inverts Habitat Integrity Diatoms Period Ecostatus SASS (SPI) ASPT Instream Riparian Score 2004 133 6.1 Nil Poor Poor Fair 2006 82 4.56 Good Fair Poor Fair 2007 96 6.83 Poor Fair Poor Poor
2.3.4 Drivers and pressures
The following impacts are a threat to this catchment: Uncontrolled and excessive sand mining activities; Loss of habitats supporting aquatic biota;
2.4 Catchment 4: Mlazi River The Mlazi Catchment is approximately 49.1 km2 and receives inputs from the upper reaches of the catchment. The Mlazi River enters the Shongweni Dam which is situated at the outlet of the catchment.
2.4.1 Land uses The Mlazi Catchment is dominated by settlements, 30% urban and 13% rural dwellings and as a results is subjected to various pressures associated with such land use activities. Figure 5 shows the extent of these settlement areas in relation to other types of land cover.
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2 1 3
5
4 6 7
Mlazi River
Land cover Rural dwellings Grassland / bush clumps mix Erosion Plantation Subsistence (rural) Grassland Bare rock W etlands Crops dryland Bare sand Roads
Sugarcane Crops irrigated Degraded bushland Rivers and dams
Mines and quarries Forest Degraded grassland
Urban Dense bush Old cultivated fields - bushland
Golf courses Bushland Smallholdings - grassland
Figure 5 Land cover map for the Mlazi Catchment (after DEAT and EKZNW, 2008)
2.4.2 Natural open spaces
Approximately 31% of the catchment comprises grassland; the remaining natural open spaces is predominantly bushveld (22%).
2.4.3 Catchment condition
Upper reaches of the Mlazi Catchment was recorded as being in a reasonably good condition despite this system being significantly affected by agricultural activities ( Table 3). However, the downstream situation shows an obvious decline in water quality as reflected by the results from the bioindicators. This decrease in water quality is likely to be as a result of impacts associated with the settlements within the catchment area. As a result the ecostatus downstream was determined as being predominantly ‘fair’ ( Table 3).
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Table 3 Summarised River Health Status for the Mlazi River from sites upstream and downstream of the catchment area (after Ethekwini State of Rivers Reports)
Aquatic Inverts Habitat Integrity Diatoms Position Period Ecostatus SASS (SPI) ASPT Instream Riparian Score 2004 186 7.2 Nil Good Good Natural u/s 2006 148 5.9 Good Good Fair Good 2007 149 6.5 Good Good Fair Good 2004 126 5.7 Nil Fair Fair Fair d/s 2006 133 5.5 Poor Fair Fair Poor 2007 190 6.5 Fair Fair Fair Fair
2.4.3 Drivers and pressures
The Mlazi Catchment is negatively affected by various land use impacts; these include: Nutrient loads from intensive agricultural and industrial activities upstream; Formal and informal settlements and the likely issues associated with poorly managed sewage infrastructure, as well as the potential water quality impact from wastewater treatment works (WWTW) discharges; Alien aquatic weeds, e.g. water hyacinth, have the potential to completely cover large areas of surface water, particularly during low flow periods.
2.5 Catchment 5: Sterkspruit
The Sterkspruit Catchment is the largest catchment within the Outer West study area. With an area of approximately 123.2 km2, the Sterkspruit receives inputs from a wide range of land uses which enter the river via numerous tributaries. The Sterkspruit River enters Shongweni Dam at the catchment outlet.
2.5.1 Land uses
A fair proportion of the Sterkspruit Catchment has been subjected to various land use development where 9% of the catchment is urbanised, 7% includes rural dwellings, 6% is under sugarcane, and 6% is made up of small holdings. Roads make up approximately 4% of the catchment area.
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2 1 3
5
4 6 7
Land cover Land cover Plantation Bushland
W etlands Grassland / bush clumps mix
Sugarcane Grassland
Mines and quarries Bare sand
Urban Degraded bushland
Golf courses Degraded grassland
Rural dwellings Old cultivated fields - bushland
Subsistence (rural) Smallholdings - grassland Crops dryland Erosion r zi Rive Crops irrigated Bare rock Mla
Forest Roads
Dense bush Rivers and dams
Figure 6 Land cover map for the Sterkspruit Catchment (after DEAT and EKZNW, 2008)
2.5.2 Natural open spaces
The Sterkspruit Catchment is dominated by grassland (40%) followed by bushveld (20%). A small portion of the catchment includes grassland/bush clumps (3%) and forest (1%).
2.5.3 Catchment condition
The upper reaches of the Sterkspruit Catchment is affected largely by industrial activities, rural dwellings and subsistence agriculture. As a consequence, the overall catchment ecological condition was found to be ‘fair’ ( Table 4). However, the downstream catchment situation generally shows an improvement to ‘good’ as indicated during the 2006 and 2007 eThekwini SoR surveys.
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Table 4 Summarised River Health Status for the Sterkspruit from upstream and downstream sites (after Ethekwini State of Rivers Reports)
Aquatic Inverts Habitat Integrity Diatoms Position Period Ecostatus SASS (SPI) ASPT Instream Riparian Score 2004 158 6.1 Nil Fair Good Fair u/s 2006 152 5.58 Poor Good Fair Poor 2007 158 5.64 Good Good Fair Fair 2004 177 6.8 Nil Good Good Good d/s 2006 152 6.3 Poor Good Good Fair 2007 121 6.4 Fair Good Good Good
2.5.4 Drivers and pressures The main factors that potentially affecting the Sterkspruit Catchment include: Poor water quality arising from industrial activities around Hammarsdale and the generation of industrial effluents; Effluents entering the Sterksrpuit via the Hammarsdale WWTW; and Alien weed infestation, particularly to the riparian areas.
2.6 Catchment 6: Wekeweke River The Wekeweke Catchment has an area of approximately 26.0 km2 and enters directly into Shongweni Dam at the catchment outlet.
2.6.1 Land uses The Wekeweke Catchment is dominated by sugarcane and small holdings which respectively make up 31 and 17% of the catchment area. Urban and rural settlements make up approximately 11% of the catchment.
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2 1 3
5
4 6 7
Land cover Land cover Plantation Bushland
W etlands Grassland / bush clumps mix
Sugarcane Grassland
Mines and quarries Bare sand
Urban Degraded bushland
Golf courses Degraded grassland
Rural dwellings Old cultivated fields - bushland
Subsistence (rural) Smallholdings - grassland
Crops dryland Erosion
Crops irrigated Bare rock River Forest Roads Mlazi Dense bush Rivers and dams
Figure 7 Land cover map for the Wekeweke Catchment (after DEAT and EKZNW, 2008)
2.6.2 Natural open spaces The natural open spaces of the Wekeweke Catchment comprise bushveld 17%, grassland (11%), grassland/bush clumps (4%) and forest (3%).
2.6.3 Catchment condition No aquatic biomonitoring has been conducted for the Wekeweke River, however, given the types and extent of land uses within the catchment, it likely to be better either ‘good’ or ‘fair’. 2.6.4 Drivers and pressures The dominant drivers affecting this catchment are likely to be associated with sugarcane farming and septic tank systems associated with the small holdings. Although the latter is likely have minor impact of the overall catchment.
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2.7 Catchment 7: Umhlatuzana River The Umhlatuzana Catchment is the smallest catchment within the Outer West with an area of approximately 20.6 km2. Only a certain portion of the actual catchment area falls within the study area and therefore it is difficult to make sound inferences based on present land use impacts. The Umhlatuzana River does not enter the uMngeni and Umlaas systems and drains a predominantly urbanised catchment before entering the Durban Harbour.
2.7.1 Land uses
The uMhlatuzana Catchment is heterogenous in nature, comprising a mixture of agricultural and urban developments. In terms of agriculture, 9% of the catchment includes sugarcane, 4% small holdings, and 4% plantation. Urban settlements, roads, rural dwellings respectively each make up 9, 5, and 3% of the catchment area respectively.
2 1 3
5
4 6 7
Land cover Land cover Plantation Bushland
W etlands Grassland / bush clumps mix Umhla Sugarcane Grassland tuzana River Mines and quarries Bare sand
Urban Degraded bushland
Golf courses Degraded grassland
Rural dwellings Old cultivated fields - bushland
Subsistence (rural) Smallholdings - grassland
Crops dryland Erosion
Crops irrigated Bare rock iver Roads Mlazi R Forest Dense bush Rivers and dams
Figure 8 Land cover map for the uMhlatuzana Catchment (after DEAT and EKZNW, 2008)
2.7.2 Natural open spaces
The uMhlatuzana Catchment is dominated by bushveld and grassland, which respectively make up 29 and 22% of the catchment area. Grassland/bush clumps and forests each make up 6% of the catchment.
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2.7.3 Catchment condition
The upper uMhlatuzana Catchment was found to be in a ‘good’ condition during the SoR surveys as indicated by the overall ecostatus. By contrast, the downstream reaches show the results of impacts due to various land use activities. As a result the overall ecological condition was recorded as being generally ‘fair’ for the downstream catchment area.
Table 5 Summarised River Health Status for the uMhlatuzana River (after Ethekwini State of Rivers Reports)
Aquatic Inverts Habitat Integrity Diatoms Position Period Ecostatus SASS (SPI) ASPT Instream Riparian Score 2006 66 5.08 Natural Natural Natural Natural u/s 2007 76 4.75 Good Natural Natural Good 2004 96 6.0 Nil Fair Good Fair d/s 2006 65 4.3 Poor Fair Fair Poor 2007 75 5.4 Good Fair Fair Fair
2.7.4 Drivers and pressures
The main factors potentially affecting the uMhlatuzana Catchment include: Alien weed infestation (e.g. Triffid weed, Lantana, Bugweed, Mauritius Thorn, etc.) particularly to the riparian areas; Nutrient enrichment from various activities, most notably, WWTWs; and Limited seepage from septic tanks situated in the upper reaches of the catchment.
2.8 Summary of catchment condition
2.8.1 Terrestrial environment
Habitat degradation and alien plant infestation varies throughout the Outer West. For each of the catchments, the estimated degree of habitat degradation and alien plant infestation is summarised in Figure 9 below.
The Mshwati Catchment (i.e. Catchment 1) is shown to have the greatest amount of degraded habitat, this is particularly evident by the extensive gully erosion which is mostly likely be resulting from poor land use management practices. However, the Umhlatuzana and Wekeweke Catchments (i.e. Catchment 7 and 6) are considered to be more severely
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MUNICIPALITY AND LOCAL AREA PLANS impacted by land use activities when the combined effects of habitat degradation and alien plant infestation are taken into account (Figure 9). Areas found to be least impacted include Catchment 2 and 3, namely the Mngcweni and Sikelekehleni Catchments.
100 90 Natural habitat Degraded Infestation 80 70
60 50
Area (%) Area 40 30 20 10 0 1 2 3 4 5 6 7 Catchment
Figure 9: Proportion of catchment areas that consist of natural habitat and the extent of these areas that are degraded and/or moderately/highly infested by alien plants
Throughout the Outer West, wetland habitats are considered to be the most degraded (Figure 10). It is therefore likely that the low alien plant infestation is incorrect as infestations are expected to be more closely aligned with habitat degradation estimates. Thicket and woodland habitat areas have also been subjected to fair amounts of deterioration whereas forest and grassland habitats have reasonably low levels of degradation.
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100 Degraded Infestation 90
80
70
60
50
Area (%) Area 40
30
20
10
0 Forest Wetland Grassland Thicket Woodland
Figure 10: Summary of habitat areas within the Outer West that are degraded and the proportion of habitats that are moderately/highly infested by alien plants
2.8.2 Aquatic environment
Integration of the overall ecostatus results representing each of the catchments reveals that the catchment ecological conditions range from ‘good’ to ‘fair’. The summary of these results are shown in Figure 11. Only one catchment was found to be in a ‘good’ condition between 2004 and 2007, namely the Mngcweni Catchment. Three of the catchments were found to be generally in a ‘fair’ condition whilst one catchment, Sikelekehleni, was recorded as ‘poor’. No information was available for the Mshwati and Wekeweke Catchments in terms of present ecological status. However, given the present land use status it can be assumed with a reasonable amount of confidence that these catchments systems are likely to be in a condition that is no better than ‘fair’.
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2 1 3
5
4 6 7
Ecostatus Good Fair Poor Fair (predicted)
Figure 11 Graphical summary of ecological status of respective catchments within the Outer West area. Grey areas indicate no data availability.
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3. BIODIVERSITY ASSETS STATUS QUO
3.1 Aquatic ecosystems The Outer West study area comprises an extensive freshwater resource system consisting of rivers, dams and wetlands. These systems are valuable to the Outer West because of the important ecological and hydrological functions that they offer humans societies and the environment. For example, aquatic ecosystems support an array of biota, such as frogs, fish, aquatic macroinvertebrates, and aquatic and riverine plants, however they also benefit societal system through the supply of valuable goods and services (e.g. water purification, supply of potable water, nutrient assimilation etc.).
3.1.1 Rivers and dams The Outer West is dominated by a complex network of rivers and streams that drain the landscape (Figure 12). Consequently, and depending on the types and extents of land use activities, these rivers are likely to receive significant impacts in future which will then affect the water quality and hydrological processes of these systems. These in turn will influence the dynamics of dams that are situated downstream, for example Inanda and Shongweni Dams.
River
Dam
Figure 12: Spatial network of rivers and major dams that drain the Outer West
The rivers within the Outer West are known to support various biota. In terms of fish, the catchments within the uMngeni system contain indigenous fish species such as the KwaZulu- Natal Yellow Fish Labeobarbus natalensis and Redtail Barb Barbus gurneyi. A brief fish survey Page 22 of 37
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MUNICIPALITY AND LOCAL AREA PLANS during 2008 confirmed the presence of L. natalensis, Sharptooth Catfish Clarius gariepinus, Mozambique Tilapia Oreochromis mossambicus and Southern Mouthbrooder Pseudocrenilabrus philander within the Mngcweni River. In addition to supporting aquatic biodiversity, the river systems within the Outer West provide a number a goods and services. A summary of these services is given in Table 6Error! Reference source not found. below.
Table 6: Examples of goods and services provided by healthy rivers (after Meyer, 1997).
Goods Services Clean water for drinking, washing, Cleansing and detoxifying water and other uses Diluting pollutants Adequate supply of water for Producing fish for angling irrigation and industry Reducing sediment inputs to coastal Uncontaminated foods (e.g. fish, zone crayfish, shellfish) Providing aesthetic pleasures Challenging waterways for canoeing Maintaining water supply Sites for swimming Decomposing organic matter An environment for contemplation and Storing and regenerating essential spiritual renewal elements Unique species to observe
3.1.2 Wetlands As with rivers, wetlands also provide a wide variety of important functions. These include, but are not limited to, include improving water quality (reductions in: suspended sediments; excess plant nutrients; and other pollutants), streamflow regulation (flood attenuation, water storage and sustaining streamflow), groundwater recharge, erosion control, and the maintenance of biodiversity for wetland-dependant fauna and flora (Kotze and Breen, 1994).
Spatial coverage of wetlands are limited as far as defining the presence of wetlands within the Outer West. To account for lack a spatial representation of wetlands for the study area, the potential distribution of wetlands was determined using a method of topographic analysis as described in Dely et al. (1999). This process involved generating a high resolution digital elevation model (DEM) from two meter contours as obtained from the eThekwini Municipality. The degree slopes were then calculated and mapped into suitable slope classes and grouped according to slope categories suitable for wetland classification, namely <1o, 1 - 3o, 3 - 5o, 5 - 10o, and >10o that illustrate incidence area of varying degrees of slope. The first two of these categories were selected as these low slopes are likely to contain permanently saturated wetland areas (Dely et al., 1999). Figure 13 shows the result from wetland analysis illustrating potential wetland areas.
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Potential wetlands (degree slope) < 1 1 - 3
Figure 13: Spatial distribution of potential wetlands based on a topographical analysis
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3.2 Terrestrial ecosystems
3.2.1 Vegetation types The Mucina and Rutherford (2006) classification system and map of South African vegetation types highlight that several types of vegetation occur within the study area; they are grouped into three biomes, namely, savanna, coastal belt, and forest (Table 7Table 1). These vegetation types are important from the basis of supporting biodiversity, particularly through the provision of habitat for various important fauna and flora.
Table 7: Summary of the dominant vegetation types occurring within the Outer West (after Mucina and Rutherford, 2006)
Conservation Status Vegetation type Biome Area (km2)
KwaZulu-Natal Hinterland Thornveld Savanna Vulnerable 47.0 Ngongoni Veld Savanna Vulnerable 157.6 KwaZulu-Natal Sandstone Sourveld Savanna Endangered 35.5 Eastern Valley Bushveld Savanna Least Threatened 83.4 KwaZulu-Natal Coastal Belt Coastal Belt Endangered 4.8 Scarp Forest Forest Least Threatened 0.1
The Outer West is dominated primarily by vegetation communities associated with the savanna biome, particularly Ngongoni Veld and Eastern Valley Bushveld, which make up 48 and 25% of the area respectively (Table 7). In terms of conservation status, Sandstone Sourveld and Coastal Belt are considered to be most important due to the degree of transformation and their limited protection through formally conserved areas; hence these vegetation types are regarded as being Endangered. Eastern Valley Bushveld and Scarp Forest are considered Least Threatened, primarily because of the large amount of representation or conservation associated with each vegetation type.
Figure 14 illustrates the spatial extent and distribution of these vegetation types within the Outer West study area.
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Vegetation type KwaZulu-Natal Hinterland Thornveld Ngongoni Veld KwaZulu-Natal Sandstone Sourveld Eastern Valley Bushveld KwaZulu-Natal Coastal Belt Scarp Forest
Figure 14: Spatial distribution of the vegetation types throughout the Outer West (after Mucina and Rutherford, 2006)
3.2.2. Natural habitat Each of the aforementioned vegetation types contain different habitats (plant communities) such as forests, grasslands, thickets, woodlands, wetlands, and rocky areas. These habitats
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MUNICIPALITY AND LOCAL AREA PLANS have been subjected to varying degrees of land use development and impacts. Consequently, certain areas of habitat have been completely transformed by land use activities, while others areas have deteriorated to some extent; resulting in a mosaic of natural and transformed areas with few remaining patched of pristine habitat. Figure 15 shows how the different habitats are distributed throughout the Outer West.
Vegetation community Artificial waterbody Forest Freshwater wetland Grassland Rocky Thicket Woodland
Figure 15: Map of natural habitats that presently occur within the Outer West as obtained from the eThekwini District Municipality landcover classification Page 27 of 37
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Majority of the Outer West’s natural habitat consists of thicket and woodland, which together make up approximately 35% of the study area (Table 8). Grasslands make up an additional 16%, followed by forests (4%) and wetlands (3%).
Table 8: Summary of natural habitats present within the Outer West and their relative extents
Area Vegetation type (km2) Artificial waterbody (e.g. dams) 0.9 Forest 13.2 Freshwater wetland 10.4 Grassland 54.1 Rocky 1.8 Thicket 63.0 Woodland 51.0
3.2.3 Important flora The Outer West is known to support a variety of plants species, some of which are considered important from a biodiversity conservation perspective. These include plants characterised as Red Data according to the International Union for the Conservation of Nature (IUCN)1.
The following Red Data plants have been recorded at specific areas of the Outer West by various bontanical specialists. These include Frank’s Brachystelma Branchystelma franksiae (VU), Beautiful Brachystelma Branchystelma pulchellum (NT), Ox-eyed Daisy Callilepis laureola (LC), Satin Squill Drimia robusta (DD), Wild Grape Lannea edulis (LC), and Purple-leaved Spurflower Plectranthus purpuratus (LC), Senecio exuberans (EN), and Stenoglottis woodii (LC). Other Red Data species that are likely to occur within the Outer West area include Natal Brachystelma Brachystelma natalense (CR), Prickly-leaved Cushion Euphorbia Euphorbia pulvinata (LC), Wood’s Euphorbia Euphorbia woodii (EN), Wild Penstemon Graderia scabra
1 IUCN Categories: Critically Endangered (CR) – the species is considered to be facing an extremely high risk of extinction in the wild, based on IUCN criteria Endangered (EN) – the species is considered to be facing a very high risk of extinction in the wild, based on IUCN criteria Vulnerable (VU)– the species is considered to be facing a high risk of extinction in the wild, based on IUCN criteria Near Threatened (NT) – when evaluated against IUCN criteria, does not qualify for a Threatened category but is close to qualifying for or is likely to qualify in one of those categories in the near future Least Concern (LC) – when evaluated against IUCN criteria, does not qualify for any category as Threatened or Near Threatened. Widespread and abundant species fall in this category Data Deficient (DD) – there is inadequate information regarding the species’ population size, distribution or threats for an assessment to be made
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(LC), Lotononis corymbosa (LC). Other notable species include a species of aloe Aloe parviflora and a species of orchid Habenaria chlorotica. 3.2.4 Important fauna Various Red Data fauna species are known to occur within the Outer West. These include: Mammals – Oribi Ourebia ourebi (EN); Birds – Black-rumped Buttonquail Turnix hottentotta (LC), African Marsh Harrier Circus ranivorus (LC), Montagu’s Harrier Circus pygargus (LC), Black-winged Lap- wing Vanellus melanopterus (LC), and Lanner Falcon Falco biarmicus (LC); and Amphibians – Natal Leaf-folding Frog (VU), Spotted Shovel-nosed Frog Hemisus guttatus (VU);
Other Red Data fauna that may occur within the Outer West include: Mammals – Rough-haired Golden Mole Chrysospalax villosus (EN), Swiny’s Horseshoe Bat Rhinolophus swinnyi (EN), Syke’s Monkey Cercopithecus albogularis (EN), Blue Duiker Philantomba monticola (VU), Tree Hyrax Dendrohyrax arboreus (VU), Serval Leptailurus serval (NT), Honey badger Mellivora capensis (NT), Water Rat Dasymys imcomtus (NT), and African Weasel Poecilogale albinucha (DD); Birds – Southern Ground Hornbill Bucorvus leadbeateri (LC); Amphibians – Kloof Frog Natalobatrachus bonebergi (EN); Reptiles – KwaZulu Dwarf Chamaeleon Bradypodion melanocephalum (NT), Cape Grass Lizzard Chamaesaura anguina (NT), Stripped Harlequin Snake Homoroselaps dorsalis (NT), Yellow-belied House Snake Lamprophis fuscus (NT), and Natal Black Snake Macrelaps microlepidotus (NT); and Invertebrates – Yellowish Amakosa Rocksitter Butterfly Duranta amakosa flavida (DD), Ruby-legged Giant Black Millipede Doratogonus Rubipodus (EN), and Cristulate Black Millipede Doratogonus cristulatus (LC).
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3.3 Areas of conservation importance 3.3.1 C-plan The C-plan database, developed by EKZNW, is a useful source of information for prioritising areas whereby gridded areas are scored according to the presence of important biological features. According to the C-plan, there are a number of areas within the Outer West study area that are important for the purpose of conservation of biodiversity. Other remaining areas have a lesser importance. Figure 16 shows which areas are considered by EKZNW as priority conservation areas due to their biodiversity value (i.e. “totally irreplaceable”), which areas are less important from a biodiversity conservation perspective, and those areas that are largely transformed to due to anthropogenic activities. From this it is clear that majority of the south-western corner of the study area comprises habitat that is considered “totally irreplaceable” from a biodiversity perspective. Key features that support this include the presence of important vegetation communities, namely the KwaZulu-Natal Sandstone Plateau Sourveld and North Coast Grassland, as well as the potential to support protected biota, including species of millipede (Doratogonus cristulata and D. Rubipodus) and plant (Ceropegia rudatisii and Helichrysum woodii).
C-plan Transformed Site Irreplaceability 1 (Totally Irreplaceable) >0.8 - <1 >0.6 - 0.8 >0.4 - 0.6 >0.2 - 0.4 >0 - 0.2 IRREPL = 0
Figure 16: C-plan data for the Outer West study area illustrating areas varying conservation importance (ranked according to irreplaceability) and which areas have been transformed.
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3.3.2 Metropolitan Open Space System The eThekwini District Municipality has developed a Metropolitan Open Space System (MOSS), referred to as the Durban MOSS (D’MOSS), which is a system of open space that incorporates areas of high biodiversity value linked together as a network of interconnected habitats. These areas are important from a biodiversity perspective by allowing for the protection of viable populations of biota, particularly rare and endangered species, through the conservation of various habitats and vegetation types. Figure 17 illustrates the extent of these areas as they occur within the Outer West.
MOSS
Figure 17: Spatial network of the D’MOSS within the Outer West study area
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3.3.3 Formally protected areas
The Shongweni Resources Reserve is the only formally defined area that occurs within the Outer West (Figure 18). The reserve is considered strategically important from the context of preservation and protection of habitat and biodiversity, but also serves as a significant recreational resource. Strategically, the Shongweni Reserve is vital in terms of establishing corridors of ecological importance and connectivity for the southern areas of the study area. However, from a water resources and recreational perspective, the reserve is also under threat due to deteriorating water quality within the Mlazi, Sterkfontein, and Wekeweke Catchments.
Other areas of conservation importance include urban conservancies; within the Outer West, these include the Alverstone and Hillandale Conservancies as well as the Giba Gorge precinct (Figure 18).
Hillandale Conservancy Alverstone Conservancy
Giba Gorge
Shongweni Resources Reserve
Figure 18: Distribution of nature reserves and conservancies within the Outer West study area
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3.4 Biodiversity hotspots Several key provisional areas (“hotspots”) have been identified and mapped that are considered significant in terms of the type of habitat defining the respective areas and the presence of important fauna and flora, particularly species which are classified as Red Data.
Provisional hotspots are based on existing sources of information and data and are considered separately for plant communities and biota. These are discussed in the following sections.
3.4.1 Important plant communities Important plant communities have been defined according to the types of habitats present and the conservation status of the dominant vegetation types. These areas are shown in Figure 19 and ranked according to their relative importance. Plant communities with the highest importance (i.e. “very high” importance) are located in the south-eastern areas of the Outer West and typically correspond with the threatened Sandstone Sourveld and Coastal Belt vegetation types. Communities classified as being “highly” important occur throughout the study area, the more extensive/connected of these occur predominantly in the central areas of the Outer West surrounding the Cato Ridge area.
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Importance (vegetation) Very high High Moderate Low Very low
Figure 19: Spatial distribution of important plant communities as mapped during the interim sensitivity analysis
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3.4.2 Important biota (fauna and flora) Areas considered as having a “very high” importance in terms of supporting important fauna and flora are located around the centre and toward the north of the Outer West area ( Figure 20). These areas are significant in that they are known to support a range of Red Data fauna and flora. Habitat areas surrounding these areas have a lesser importance and are considered for the purpose of providing a connected habitat network for the Red Data species. Areas defined for conservation purposes are also regarded as important given their contributions for supporting biodiversity assets, namely the Shongweni Reserve and conservancies ( Figure 20).
Importance (biota) Very high High Moderate Low Very low
Figure 20: Spatial distribution of important biota (fauna and flora) as mapped during the interim sensitivity analysis
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4. WAY FORWARD 4.1 Drivers and pressures The overview of catchments provides useful information in terms of the types of impacts received from dominant land use activities within the individual catchments, and thus the types of pressures that would typically affect the natural systems present within the catchments. This also helps to assess the relative ecological condition of the catchments which may then be used to inform the priority of catchments. The assessment of these systems was considered satisfactory, although information from the Water Authorisation Resource Management System (WARMS) database of DWA would provided additional useful information, particularly with regards to water quantity impacts associated with various permitted water users.
4.2 Biodiversity information sources Biodiversity information is important for determining areas of importance for the purpose of maintaining biodiversity assets. Such information includes a wide variety of sources that differ in terms of detail and spatial scale. The types of information made available for the Outer West study includes: Vegetation and land cover coverages; River health and catchment Ecological Importance and Sensitivity; River and wetland coverages (including floodline determinations); Conservation spatial planning tools (e.g. an interim version of eThekwini’s Systematic Conservation Plan, EKZNW C-plan, and D’MOSS) and Species-specific data from specialist studies (e.g. Red Data, rare species).
The above information sources, although useful in terms of characterising biodiversity assets, provide only a specific amount of detail. Additional information would provide a significant amount detail that would benefit the mapping procedures, particularly for identifying biodiversity hotspots and establishing ecological corridors. Other data sources that are not yet available but will be going forward include: Priority habitats as characterised by local (eThekwini Municipality) and regional (EKZNW) organizations; Other specialists studies that have been undertaken within the Outer West that have established the presence of important biota. Such studies include the investigations associated with the petroleum pipeline development that traverses the study area; Potential presence of important biota defined from species distribution patterns and habitat requirements; Known species localities determined by previous field investigations as captured and stored within EKZNW databases.
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5. REFERENCES
DEAT and EKZNW. 2008. KZN Province land-cover mapping, version 2.0 (from SPOT 2/4 Satellite imagery 2005 - 2006). KZN Department of Agriculture and Environmental Affairs and Ezemvelo KZN Wildlife. Dely, J.L., Kotze, D.C., Quinn, N.W., and Mander, J.J. 1999. A pilot project to compile an inventory and classification of wetlands in the Natal Drakensberg Park. Department of Environmental Affairs and Tourism, Pretoria. GroundTruth and eThekwini Municipality. 2006. eThekwini Municipality State of Rivers Report: Final summary report. GroundTruth and eThekwini Municipality. 2007. eThekwini Municipality State of Rivers Report: Final summary report. Kotze D.C., Breen C.M. and Quinn N.W. 1995. Wetland losses in South Africa. Department of Environmental Affairs and Tourism. Pretoria. Mucina, L. and Rutherford, M.C. 2006. The Vegetation of South Africa, Lesotho and Swaziland. Strelitzia 19. South African National Biodiversity Institute, Pretoria.
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