PARENT SESSION
Oral Session 7: GIS / Remote Sensing I.
Presiding: E Ellis and P Valko
Monday, August 2, 8:00 AM to 11:30 AM, Meeting Room B 116.
Fifty years of change in Israel: Tracking loss of open space and its ecological implications.
Orenstein, Daniel*,1, Hamburg, Steven1, 1 Brown University, Providence, RI
ABSTRACT- We are quantifying land use/land cover change (LUCC) for a 50 year period across an ecosystem gradient in Israel, and correlating this data with changes in habitat quality and quantity. Israel, 21,000 km2, is densely populated and has high biodiversity. Fifty years of rapid development has diminished natural habitats and altered ecosystem processes. Development trends, including intensification of agriculture, afforestation, urbanization and suburbanization have affected diverse ecosystems, from extremely arid to Mediterranean regions. We are building spatially explicit models of LUCC in four 300 km2 areas representing the diversity of ecosystem types in Israel. Scanned and georeferenced 1:50,000 survey maps from 1951 to 2001 are used as a basis for a Geographic Information System (GIS) analysis. Each human-built structure has been located and identified with the year the structure first appeared on a map. This data is used to generate structure density maps for each map date. With these data we quantify shifts in open space and fragmentation characteristics and then describe changes in habitat quality. These data allow us to describe the effects of development on ecosystem dynamics of both open space and developed land. Such effects include the introduction of weedy species into "natural areas," the alteration of the hydrologic cycle and in turn local climate, and shifts in plant communities as a result of afforestation or shifts in grazing regimes resulting from public policy. Preliminary results from a 285 km2 area south of Tel Aviv, along the Mediterranean, show that between 1978 and 1999 the amount of open space (defined as having fewer than 5 structures within a 1 km2 radius), fell by 20% to 80 km2, with much of the remaining open space heavily fragmented. Most of the open space that had been developed was formerly a single unmanaged ecosystem type (coastal dunes), while managed open space, e.g. agricultural or afforestation areas, was largely untouched. These patterns have resulted in alterations of the composition of remaining coastal sand dune communities.
Key words: open space, habitat fragmentation, gis, land use/land cover change