Keep the Mojave Landscape Intact : Ecology: A new law aims to sustain biological diversity in a fragile ecosystem.

Across the Mojave Desert, entire colonies of plant and animal life are in grave jeopardy of forced extinction brought on by the ravages and pressures of the modern world. Crosshatched by a mosaic of roads, power lines, pipelines and aqueducts that carry the lifeblood of modern society to metropolitan areas, the desert is being fragmented into smaller and smaller units that cannot sustain the life forms trapped within their borders.

For the past decade, I have been involved in scientific studies of the Mojave ecosystem. These studies have reinforced the view that effective management and conservation of this national treasure require the preservation of large land areas, as proposed by the California Desert Protection Act. The legislation--passed by the House two years ago but stranded in the Senate--would permit continued use of the region’s resources by humans while providing biological diversity.

While the construction of a single road might not seem likely to affect a large area of the landscape, recent scientific studies I have conducted east of Palm Springs suggest that such disruptions cause ripples of impact adjacent to construction.

When roads and pipelines cross the desert, they obstruct the natural paths of desert streams that deliver the most crucial resource--water--to organisms during infrequent rain. Desert vegetation is often reduced by 50% in areas down-slope of road and aqueduct drainage diversions.

Interior Secretary Bruce Babbitt recently recommended preserving entire ecosystems, rather than individual endangered species in isolated parks. Nowhere is this new policy more appropriate than in the Mojave Desert, and no wilderness bill before Congress is more critical than this act. (A Senate committee vote on the bill was delayed at least a week on Wednesday, pending proposed changes.)

Delicate desert ecosystems are slower to recover from human disturbance than other ecosystems. While abandoned farmland in the eastern United States may regrow to full forest in 50 years, desert left bare by human activities remains scarred for centuries. In the Mojave, scientists can measure tank tracks created 50 years ago by the mock tank battles and other military exercises conducted under Gen. George Patton. The disturbance of soils has retarded the recovery of native vegetation over large areas, leading to greater losses of soil in desert sandstorms.

Effective preservation and management of desert ecosystems must recognize that desert organisms depend on large areas for survival--just as city dwellers do. We must begin to view the desert as a large, interconnected unit of landscape. Plants and animals in lowland areas are often critically dependent upon water flowing from adjacent uplands. When the desert is fragmented into small units, the natural flow-paths are disrupted, the home range in which animals feed is confined and isolated and extinction soon follows.

Historically, we have set aside small parks to preserve endangered species or land forms that are of special historical or aesthetic significance. However, to preserve the biological integrity of the Mojave Desert ecosystem, integrated land management directed toward the preservation of entire landscapes and their natural connections is more appropriate.

Southern California is blessed by the presence of its desert landscapes, but we must act now to ensure their conservation.