on effects on human health, aesthetics, risks of air and water pollution, and the risk for endangered species. The recognition of the significance of ecosystem services and the role of biodiversity in providing these services, beyond the endangered "flagship" species, is not yet expressed in environmental impact assessments.
The major future undertaking is to assess the impacts of wastewater use, for agriculture and for biodiversity, on biodiversity and ecosystem services. With respect to using treated wastewater to sustain biodiversity, predictions for water demand and use suggest that the current allocations for nature, as well as the recommendations of environmental impact assessments may not be respected in the future. Therefore, just as treated wastewater may in the future replace freshwater for agriculture, wastewater allocation for maintaining aquatic ecosystems and water-dependent terrestrial ecosystems may replace the current allocation of freshwater. Research is therefore required now for determining the effects and the technologies appropriate for this future substitution.
Urban development in one of the prime agricultural areas of Israel, the coastal plain, is currently motivating the transfer of agriculture to the northern Negev, namely, to the semiarid belt of Israel, which is also the climatic transition zone between desert and nondesert in Israel. The water required to sustain this agricultural development will be the effluents of the urban areas in the coastal plain. The treated wastewater is already transported from there to the northern Negev, and volume of water transportation will increase and proliferate. This new agricultural development will replace natural ecosystems whose biodiversity is of prime significance (Safriel et al., 1994), and which have not undergone any process of environmental assessment. It is certainly necessary to assess the impact of this development, but it is also essential to explore methods of regional planning that will minimize the damage especially to habitats that harbor indispensable biogenetic resources.
Friedler, E., and M. Juanico. 1996. Allocation of water for rehabilitation of selected rivers in Israel. Report to KKL.
Hendelsman, E. 1990. Water as a source of life. Nature Reserves Authority (in Hebrew).
Rahamimov, A. 1996. Master Plan for the Yarkon River. Tel-Aviv, Israel: Yarkon River Authority (in Hebrew).
Safriel, U. N., S. Volis, and S. Kark. 1994. Core and peripheral populations and global climate change. Israel J. of Plant Sciences 42:331-345.