Proceedings of the Symposium on Dynamics and Management Of
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Dynamic Conservation Management of Abstract: East Mediterranean upland ecosystems Nontillable East Mediterranean Upland are severely threatened by exponential landscape degradation and by the loss of biological diver- Ecosystems1 sity through monospecies afforestation and brush encroachment. Integrated landscape ecological research, planning, management and education are therefore urgently required to reconcile the need 2 Z. Naveh for bio-ecological conservation and restoration and for socio-economic advancement. Highest at- tainable diversity can be ensured by the mainten- ance of the dynamic flow equilibrium through con- trolled grazing, cutting and burning. Flexible multipurpose management for optimization of en- vironmental protection, nature conservation, landscape and recreation amenities plus plant and animal production, should be based on ecosystem management and the creation of multi-layered fod- der, fuel and/or recreation forests. Mountainous uplands, too steep, shallow and/or 150-200 biological dry days (Naveh, 1973). Their rocky for profitable cultivation, make up large closest ecological counterparts outside the Medi- parts of the total area in all Mediterranean coun- terranean are the broad sclerophyll chaparral and tries, especially in the Eastern Mediterranean Ba- woodland in central and southern California, and sin (Table 1 ). Whereas adjacent, arable low- similar bioclimatic regions in central Chile. lands are undergoing a rapid transformation into more intensive, irrigated agriculture, these non- tillable, marginal uplands are either left to Table 1--Major land uses in East Mediterranean their fate of pastoral over-exploitation and un- countries in 1976. (After Le Houerou, 1980). controlled urban-industrial -recreational en- croachment or they are converted into closed, mon- Country Tot.area Mediter. area Cultiv. area otonous shrublands or dense, chiefly monospecies, 103 ha 103 ha percent 103 ha percent pine afforestations. Both are highly inflammable and of low value for local populations. Cyprus 924 855 100 432 50.3 Greece 13,080 8,102 62.0 2,331 28.8 There is, therefore, urgent need for new ap- Israel 2,033 1,367 67.2 433 31.7 proaches in which the conservation and rehabili- Jordan 9,178 1,400 14.4 1,175 84.0 tation of these ecosystems can be reconciled with Lebanon 1,023 1,023 100 348 34.0 socio-economic advancement of the population. Syria 14,418 6,567 35.6 5,260 80.1 This is also true for all other nonarable uplands Turkey 77,076 77,110 22.2 8,309 48.6 of similar nature in the Mediterranean Basin. Total 117,732 36,424 57.3 18,288 51.1 Forest, maqui, shrub pasture Country 3 3 ECOLOGICAL CHARACTERISTICS 10 ha percent 10 ha percent Cyprus 330 38.5 9.3 10.9 The greater part of these uplands is confined Greece 2,618 32.3 3,153 38.9 to coastal foothills and lower mountain regions Israel 116 8.5 818 59.8 with a typical Koeppen Cs "olive climate" -- dry, Jordan 125 8.9 100 7.1 hot summers with wet, mild winters. This largely Lebanon 570 55.7 105 10.3 subhumid zone can be further divided into a drier Syria 457 7.0 850 12.9 xerothermo-mediterranean subzone merging into sub- Turkey 6,051 35.4 2,750 16.6 desert, and into a slightly wetter, cooler, accen- Total 10,267 26.6 7,785.3 22.3 tuated thermomediterranean subzone merging into the humid, attenuated thermomediterranean zone (UNESCO, 1963). Both are within the 400-800 mil- According to the extensive geobotanical des- limeter isohyetes, with true "Mediterranean fire cription by Zohary (1973), both subzones belong bioclimes" in which acute fire hazards prevail for to the Eu-Mediterranean vegetation belt of Quer- cetalia calliprini maquis and forests. 1Prepared for the Symposium on Dynamics and Great heterogeneity in macro- and micro-site Management of Mediterranean-type Ecosystems, June conditions and a long history of active human 22-26, 1981, San Diego, California. modification have induced large floristic, faun- istic, structural diversity which has contributed 2Associate Professor of Ecology, Technion-Is- much to the attractiveness of these semi-natural rael Institute of Technology, Haifa, Israel landscapes and their complex, intricate vegetation 32 000. Gen. Tech. Rep. PSW-58. Berkeley, CA: Pacific Southwest Forest and Range 20 Experiment Station, Forest Service, U.S. Department of Agriculture; 1982. mosaics. These consist of dynamic regeneration- ceous and sub-shrub understorey, and semi-open, degradation patterns in sclerophyll, dwarfshrub disturbed multi-layered shrublands, in structural, and herbaceous plant communities. They range, ac- floristic and faunistic diversity, are very strik- cording to site conditions and past and present ing (Naveh & Whittaker, 1979). There seems, there- land use pressures, from rich, productive open fore, to be very little justification for complete grasslands and woodlands to severely depleted prolonged protection as a conservation management dwarfshrub and man-made rock deserts, and from policy aiming at reconstructing the so-called "ma- rich multi-layered semi-open shrublands and for- qui forest climax", as suggested by Tomaselli ests to one-to-two-layered, closed tall shrub (1977). maquis. On the contrary -- one of the oldest existing Most soils are shallow and/or rocky; many are Q. ilex "climax" forests in Sardinia, with huge heavily eroded, especially those which were ter- scattered oak trees up to 1000 years old, is main- raced and cultivated and later on neglected. The taining its open park-like structure and reproduc- fertile, well-structured, abundant terra rosa and ing itself under traditional swine and cattle gra- brown forest soils (derived from hard limestone zing. Removing pastoralists would only great- and dolomites of Upper Cretaceous and Tertiary ly increase fire hazards and endanger the forest rocks) and the dark rendzinas (derived from soft (Susmel and others, 1976). limestone with hard calcareous "nari" crusts), as well as the heavier basaltic soils (of volcanic In the xerothermic subzone, the natural poten- origin), are conducive to vigorous growth of her- tial vegetation consists of thermophylous park- baceous plants. These include many valuable an- like maquis and shrublands made up of the valuable nual and perennial grasses, annual legumes and Carob tree (Ceratonia siliqua) and Pistacia lentis- beautifully flowering geophytes, forming produc- cus. This evergreen shrub, combining low palata- tive, stable shrub-free grasslands and woodlands bility and great drought resistance with vigorous in the xerothermic belts and their arid ecotones. regeneration powers after fire and cutting, is one However, in the more humid regions these pasture of the last shrubs to survive over large areas of plants occur either as derived grasslands on aban- overgrazed, depleted, mosaic-like shrub-grassland doned fields, terraces and poorly drained shallow with low- or non-palatable early maturing annuals. grumosols or as patchy understories of shrublands. However, if these pressures are released, a strik- ing vegetative recovery of woody plants occurs, to- The highly calcareous, pale xerorendzinas (de- gether with a very species-rich, productive grass rived from soft limestone, chalk and Eocenic rock cover. In such a xerothermic, recovered Pistacia marls) as well as the brown soils derived from shrubland, on 1/10 hectare, 52 woody, 127 herbace- granitic rock, sandstone and metamorphic rock, are ous, 14 reptile, 7 rodent and 31 bird species were much poorer and highly erodable. Here, herbaceous recorded (Naveh & Warburg, 1976). plants are much less competitive and they are pre- sently mostly covered by low-productive and spe- Another important formation in drier parts, con- cies-poor "batha" (in Hebrew) and "phrygana" (in sists of deciduous oak woodlands -- Quercus itha- Greek) dwarfshrub communities dominated by Sacro- burense in Israel and Q. macrolepis in Turkey -- poterium spinosa, Cistus and aromatic Labiatea very much resembling Q. douglasii woodlands in Cal- species. Being favored by frequent burning and ifornia. Here, a very species-rich, productive heavy grazing, these occupy large areas in all grass and legume understorey is maintained under east Mediterranean countries. Their conversion moderate grazing pressures. However, by over- or into more valuable ecosystems should be considered under-grazing species diversity is reduced, either therefore, as a major management challenge. to unpalatable weedy forbs or to tall aggressive grasses and perennial thistles (Naveh & Whittaker, The natural potential vegetation of the cooler, 1979). wetter subzone consists of maquis dominated by Quercus calliprinos (in Greece by its western vi- cariant Q. coccifera) and other sclerophyll, most- THE DISTORTION OF DYNAMIC FLOW EQUILIBRIUM ly evergreen, phanerophytes. Distinguished by du- BY MODERN LAND USES al root systems, spreading both horizontally and penetrating deep into rock cracks, and by resprou- Mediterranean land use and its impact on the ting after burning, grazing and cutting, they also landscape can be described as being cycles of mul- respond favorably to pruning and coppicing of one tivariate anthropogenic biofunctions, corresponding stem. If resprouting from suckers is prevented by to the main phases of changing land uses (Naveh & recutting. or browsing, they soon attain the sta- Dan, 1973). These started hundreds of thousands ture of trees. Thereby, closed one-layered, very of years ago with the use of fire by paleolithic fire prone maqui thickets which have been protec- hunter-gatherer economies, which were