Development and application of a soil organic matter based soil quality index in mineralized terrane of the Western US

Blecker, S.W. and STILLINGS, L.L. and AMACHER, M.C. and Ippolito, J.A. and DECRAOPPEO, N.M. (2012) Development and application of a soil organic matter based soil quality index in mineralized terrane of the Western US. Environmental Earth Sciences. 68:1887-1901. 12 August 2012.

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Abstract

Soil quality indices provide a means of distilling large amounts of data into a single metric that evaluates the soil’s ability to carry out key ecosystem functions. Primarily developed in agroecosytems, then forested ecosystems, we set out to develop and apply an index using the relation between soil organic matter and key soil abiotic and biotic properties in more semi-arid of the Western US arid systems impacted by different geologic mineralization types. We studied these relations in three different mineralization types: serpentine, acid sulfate and Cu/Mo porphyry systems at four different sites in California and Nevada. Soil samples were collected from undisturbed soils in both mineralized and nearby unmineralized terrane as well as waste rock and tailings. We measured eight different microbial parameters (carbon substrate utilization, microbial biomass-C, mineralized-C, mineralized-N and enzyme activities of acid phosphatase, alkaline phosphatase, arylsulfatase, and fluorescein diacetate) along with a number of physicochemical parameters. We developed multiple linear regression models between these parameters and both total organic carbon and total nitrogen, and used the ratio of predicted to measured values as our soil quality index. In most instances, pooling unmineralized and mineralized soil data within a given study site resulted in lower model correlations. Enzyme activity was a consistent explanatory variable in the models across the study sites, while carbon substrate utilization rarely occurred in the models. Though similar indicators were significant in models across different mineralization types, pooling data across sites inhibited model differentiation of undisturbed and disturbed sites. This procedure could be used to monitor recovery of disturbed systems in mineralized terrane and to help link scientific and management disciplines.

Item Type:	Article
NWISRL Publication Number:	1453
Subjects:	Soil > Chemistry > Nitrogen Soil
Depositing User:	Users 6 not found.
Date Deposited:	08 Apr 2013 22:13
Last Modified:	08 Apr 2013 22:13
Item ID:	1489
URI:	https://eprints.nwisrl.ars.usda.gov/id/eprint/1489