AN ASSESSMENT OF OPEN SPACES IN CENTRAL ISRAEL: THE BIOLOGICAL ASPECT
by Yehoshua Shkedy
Department of Information Systems, Nature Reserves Authority
13 Helene Hamalka Street, Jerusalem 91900
Of all the global problems which confront the biosphere today, few would argue that the extinction of species and destruction of ecosystems has the most serious consequencesand it is irreversible. Worldwide, and particularly in a small country such as Israel, with a high rate of industrialization and urbanization, on the one hand, and a rich variety of flora and fauna, on the other hand, the conservation of biological diversity presents a major challenge.
Although nature conservation has been well established in Israel since the early 1960s, the momentum of population, agricultural and industrial growth poses a major threat to the county’s unique natural heritage. While nature conservation is safeguarded by the Nature Reserves Authority (NRA), both within and outside nature reserves, renewed efforts must now be directed toward the protection of Israel’s natural open spaces. This is imperative for two basic reasons: first, many of Israel’s precious natural assets are currently not protected within nature reserves due to the lengthy process required for declaring new reserves and, second, the small and fragmented nature of most nature reserves make them particularly vulnerable to what occurs outside their borders. Lack of nature protection outside the bounds of nature reserves threatens the future of ecosystems and species within the reserves as well.
Recognition of the growing threat to the country’s natural heritage has led to several initiatives by Israel’s nature protection bodies, among them the Nature Reserves Authority (NRA) and the Jewish National Fund
(JNF). For the past several years, these two bodies have cooperated in developing a database for the assessment of open spaces in Israel. Geographical and lithological data, collected by the JNF, and botanic data, collected by the NRA, are currently being compiled, evaluated and mapped in the Geographical Information System at the NRA.
This paper deals exclusively with the assessment of Israel’s open spaces
(in the area between Beersheba and Nazareth) for nature conservation purposes.
Several fundamental methods for the preservation of organisms have been identified and implemented worldwide, among which are the following:
* Determining mini-goals for the preservation of specific species, including the necessary conditions and activities for their preservation. While this method was effective in helping to preserve such species as gazelles in Israel, several whale species and the bald eagle, it has frequently failed due to the fact that in determining the conditions necessary for species preservation, the conditions necessary for the preservation of the ecosystem in which the species live were not taken into account.
* Identifying and preserving most of the ecosystems in a region under the assumption that the protection of a maximum of ecosystems will preserve a maximum of biodiversity.
* Examining the necessary conditions for the functioning of an ecosystem as a whole under the assumption that the rate of species extinction in relation to the rate of colonization decreases as the ecosystem functions better. (The main disadvantage in the latter two methods is that they do not relate to unique species which may become extinct if specific actions are not taken to preserve them).
* Protecting "keystone species," which may not necessarily be rare, but whose vitality is an indicator of the functionality of the ecosystem as a whole.
When selecting the optimal method for assessing Israel’s open natural spaces for purposes of nature conservation, the NRA decided to base its assessment on the contribution of open spaces to plant protection. Since plants comprise most of the biomass of all terrestrial ecosystems, their central role as primary producers makes them prime candidates on which to focus for nature conservation purposes. The ecological criteria which guided the assessment of Israel’s open spaces were based on the first three methods enumerated above, namely preservation of unique or rare species and ecosystems at risk of extinction, areas of high biodiversity and large and dense areas having the potential to function naturally over time. Keystone species were not identified.
Humankind’s responsibility to protect rare and endangered species, communities and ecosystems rests on both moral and utilitarian grounds. On the one hand, it is incumbent upon humankind to prevent the further disappearance of species and ecosystems since human intervention is largely responsible for the decline and disappearance of species. On the other hand, it is assumed that the conservation of rare communities and ecosystems will help preserve rare species as well. Furthermore, rare species frequently serve as bioindicators for the health and stability of the ecosystem as a whole.
Rare ecosystems, by definition, require special protection. However, because such ecosystemsand especially those damaged by human activitydo not rank high when compared to other geographical areas in terms of biodiversity level, they cannot be assessed according to the same criteria used for more common ecosystems. In Israel, the sand and kurkar ecosystem of the coastal stripwhich is globally uniqueconstitutes the most endangered ecosystem. Continued human intervention, largely in the form of construction and quarrying, threatens its very survival. The rarity of this ecosystem, combined with the fact that it supports a relatively large number of endemic species and a wide variety of fauna
(e.g. rodents, reptiles and anthropods), is responsible for the decision to grant Israel’s sand and kurkar regions top priority, without further analysis.
The second ecological criterion used to assess Israel’s open spaces is their importance for biodiversity conservation. The Biological Diversity Convention, which was ratified by Israel in 1995, is the first global convention to relate to all aspects of biological diversity: species diversity, ecosystem diversity and genetic diversity. While methods for measuring and assessing genetic diversity have been developed in recent years, an assessment of Israel’s genetic biodiversity is not expected in the near future. Therefore, the assessment of biodiversity in Israel’s open spaces was based solely on the diversity of species and plant communities, on the assumption that plant community diversity is an indicator of ecosystem diversity.
The third criterion used to assess open spaces was the preservation of areas likely to sustain functioning ecosystems for a long time and areas which are vital for the protection of other adjacent regions. The accumulated experience of some 50 years of nature conservation throughout the world supports the assumption that biodiversity is better preserved in large rather than in small areas, in connected rather than in fragmented areas. While the importance of regions as corridors for distribution has not been conclusively determined, most scientists have called for the preservation of as many wide corridors as possible as conduits for animals and plants in a fragmented landscape.
To comply with the third criterion, the Nature Reserves Authority is trying to direct its conservation efforts to large areas, to areas that are connected to other areas with corridors that allow distribution of plants and animals, and to areas that are surrounded by a buffer zone.
METHODS AND RESULTS
For the purpose of data collection, the country was divided into three main regionsnorth, central and southaccording to their geographic and botanic proximity. Data collection was based on field surveys, and to a lesser extent on the existing botanic literature and on aerial photographs. Areas with natural vegetation were divided into polygonsgenerally not less than 10,0000 square meters in areaaccording to plant communities. Geographically adjacent polygons with similar botanic composition were then combined into 26 analysis regions. Each region was ranked in comparison to the other regions according to the criteria described above, namely rarity, biodiversity and functionality. Rarity was assessed in terms of the number of species and plant communities expected to disappear if appropriate conservation activities are not taken. Biodiversity was assessed in terms of an inventory of species and communities. Functionality was assessed in terms of the chances of the region to support ecosystems over time as determined by such factors as size of the area, its importance as a potential corridor for plants and animals, and the relation between the area and its periphery. The three criteria were then weighted in a simple algorithm to yield a final score ranging between 0 and 100. (See accompanying map).
In total, 5650 square kilometers were surveyed, of which 4004 square kilometers were agricultural areas, 483 square kilometers were forested areas planted by the Jewish National Fund and 903 square kilometers were natural vegetation areas. The rest of the area comprised built up regions, water reservoirs and a coastal strip bare of vegetation. Of the total natural area, only 242 square kilometers have been allocated for conservation of which 119 square kilometers are currently undergoing preliminary statutory processes and it is unclear whether they will be declared nature reserves.
Based on the above assessment, the following regions ranked highest: Beit Guvrin, Adulam, and Lahav (all of which constitute a unique corridor between the desert and the Mediterranean ecosystems) and Mount Hurshan (in the region of Ramat Menashe between Mount Carmel in the north and Samaria in the south). The Jerusalem area was among the areas which ranked much lower, but this region should be preserved for its special landscapes, including JNF forests, and for its rich multitude of recreational and historical sites.
DISCUSSION OF RESULTS
The assessment of Israel’s open spaces for national planning purposes should take into account the different functions of open landscapesfrom nature conservation, afforestation, recreation, agriculture and preservation of cultural and historic sites to the designation of land reserves for building and industry. However, when formulating national priorities for the allocation of open spaces, planners should recognize the fact that the conversion of open spaces into built areas is an irreversible process: a "natural" area once transformed into a built area can never again be recreated. At the same time, it should be remembered that while planted and agricultural areas are assumed to be better suited to nature conservation than built or industrial areasbecause they serve as distribution corridors for flora and fauna and as shelters for rare species and sink populationsthey too carry risks to nature conservation, especially in terms of pesticides, land treatment and pests. Finally, when reviewing the results of the NRA assessment, it should be remembered that the study did not relate to several important aspects of nature conservation, such as the preservation of fauna, small but essential ecosystems such as endangered wetland habitats, rare species within very small areas, nesting sites, or unique geological phenomena. These and other aspects of nature conservation require source treatment on the appropriate level.
Bearing in mind these reservations, the NRA study is expected to make an important contribution to the conservation of biodiversity in Israel within the overall context of open space preservation. Based on the study, the following recommendations were made with regard to Israel’s most important regions from the point of view of nature conservation:
* Special attention should be paid to Israel’s sand and kurkar areas because of their rarity value. Since Israel’s sand reserves for quarrying purposes are already limited, sand import for building purposes should be encouraged and sand quarrying should be significantly reduced. Concurrently, steps should be taken to preserve Israel’s sand areas through the declaration of sand reserves and parks.
* Special attention should be granted to the continuum of natural open space between the northern Negev and the Jerusalem corridor which constitutes a unique transition zone between desert and Mediterranean ecosystems. This continuous area, measuring only 60 kilometers in length, is globally unique in that it serves as a meeting point for Saharo-Arabian, Mediterranean and Irano-Turanian biota. It is recommended that a biosphere reserve be established in this area which will include areas for nature protection, planted forests, national parks, agriculture and areas for building and industry in the environs of existing settlements.
* The Ramat Menashe and Alonim regions deserve special protection both in terms of their inherent value and in terms of their function as the sole bridge connecting the Carmel and Samaria in the south and the Carmel and the Galilee in the north. Disruption of the Carmel from these two areas may result in genetic stress to small Carmel populations, loss of regeneration capacity in case of the outbreak of disease, and loss of biodiversity.
* Nature conservation in Samaria is especially important since this region is the only natural corridor connecting between Mediterranean communities in the Judean Mountains and those in the Carmel and the Galilee. Furthermore, the slopes of Samaria east of Rosh Ha’Ayin serve as the last remaining natural "green lung" for residents of the Tel Aviv-Dan metropolitan area.
* The Besor-Gerar region in the Negev should be granted high priority for conservation because of its botanic diversity and uniqueness.
Hopefully, these recommendations will guide not only the NRA’s priorities for the declaration of nature reserves in the future but will direct present development initiatives toward less sensitive areas from the point of view of nature conservation for the mutual benefit of both man and the natural environment which sustains him.
Acknowledgment: My special thanks to A. Sabah and M. Wallzcak for the field surveys, to A. Rabinowitz for her excellent advice, to E. Frankenberg and Y. Cohen for their support, to D. Malkinson for his enlightening comments, and to the entire GIS staff headed by Y. Magal for guiding me through the intricacies of the system. Special thanks to the initiators of this important project both in the Nature Reserves Authority and the Jewish National Fund.