PARENT SESSION
Oral Session #61: Arid Lands Restoration.
Presiding: S. Loftin
Wednesday, August 7. 1:00 PM to 4:45 PM. Mohave Meeting Room, TCC.
Habitat restoration on retired agricultural lands in the San Joaquin Valley, I: Vegetation.
Ritter, Nur*,1, Uptain, Curt1, Kelley, Patrick1, Willaims, Daniel1, 1 California State University Stanislaus, Endangered Species Recovery Program, Turlock, CA
ABSTRACT- Substantial portions of the western side of the San Joaquin Valley are characterized by high groundwater levels and high concentrations of heavy metals and salts, resulting in relatively poor agricultural lands. Furthermore, the elimination of contaminated drainage water that accumulates from their irrigation is a chronic problem. Retirement and restoration of native habitats is potentially one way to solve the accumulation of drainage water and concomitantly provide habitat for wildlife. In 1998, we established plots on approximately 800 acres of land in western Fresno County in order to study various restoration techniques and to monitor temporal changes in restored upland habitat. The study consists of a randomized block design with four treatments in five blocks. Treatments are: contouring with phased native plant introduction; contouring with no native plant introduction; native plant introduction with no contouring; and, no treatment. Seed of native species was imprinted on the study plots, augmented by planted seedlings. The first 3 years of data indicated that restoration of both annual and perennial native plants from seedlings was problematic. Survivorship of these plants was less than 34% for all species planted after the first year and virtually none survived after the second year. Although imprinting of native annual and perennial species was more successful, introduced species far outweighed native species, both in richness and abundance. However, interpretation of the data was confounded by a particularly poor growing season in 2001. An ordination of the vegetation data indicated that block effects were present during the baseline year; in subsequent years these effects became more pronounced.
KEY WORDS: arid land restoration, San Joaquin Valley, DCA