Wednesday, November 7, 2007
302-8

Soil Survey—Research Opportunities: Examples from Yosemite National Park, California.

Ronald Taskey, 1 Grand Ave., California Polytechnic State University, California Polytechnic State University, Soil Science Department, San Luis Obispo, CA 93407

Although field researchers often refer to soil surveys for taxonomic and map unit classifications, they seldom look to soil surveys for research hypotheses. Likewise, soil mappers rarely point out research needs in their manuscripts. Given that soil surveys can reveal otherwise unknown conditions and relationships, this lack of collaboration causes many potential opportunities to be missed. The soil survey of Yosemite National Park, California generated a wealth of data that suggest worthy projects for hypothesis-driven research. This poster highlights some examples: •Significant changes in soil chemical and mineralogical properties occur at about 2,300 m elevation. •The majority of soils are hydrophobic, regardless of apparent fire history. •A band of ancient land failures runs along the Park's southwestern edge. •Shallow soils are rare—even at high elevations where rock outcrop dominates. •Meadows have the most complex soils and significant volcanic ash. •West of the Sierran crest, cryic soils extend about 400 m lower elevation than was previously recognized; the cryic-frigid boundary falls more than 500 m higher on the east side than the west side. •In most soils, A horizons contain most nutrients; lower horizons contain little nutrient. •Burrowing animals and plant roots appear to inhibit argillic horizon formation in subalpine areas. •Some soils in glacially-dominated high elevation areas appear to be prePleistocene in age. •Pollen depositions could be significant nutrient sources at high elevation. •Some soils apparently went along for the ride with Sierran uplift. Is each of these observations reliable? What is the cause of each condition? What are the ecological, hydrological, and management implications? Soil survey can make observations, raise questions, and pose hypotheses; research can provide answers.