Submitted to: Applied and Environmental Soil Science
Publication Type: Peer reviewed journal
Publication Acceptance Date: 1/26/2011
Publication Date: 4/1/2011
Publication URL: naldc.nal.usda.gov.d2.nal.usda.gov/download/49469/PDF
Citation: Smith, J.L., Halvorson, J.J. 2011. Field scale studies on the spatial variability of soil quality indicators in Washington State, USA. Applied and Environmental Soil Science. 2011:1-7. Article ID 198737. DOI: 10.1155/2011/198737. Interpretive Summary: Arable lands are needed for sustainable agricultural systems to support an ever growing human population. Soil quality needs to be defined to assure the new arable land is sustainable. We found that basic soil measurements were adequate for describing landscape level arable land. By combining the measured soil parameters we were able to make maps of the landscape that better described the potentially more productive areas of the landscape. The combination of soil quality parameters to predict productive and sustainable land areas for crop production is important for humankind now and in the future as the United Nations are trying to identify new land that will produce food for an exploding human population.
Technical Abstract: Arable lands are needed for sustainable agricultural systems to support an ever growing human population. Soil quality needs to be defined to assure the new arable land is sustainable. To evaluate soil quality a number of soil attributes will need to be measured, evaluated and integrated into a soil quality index using the multivariable indicator kriging (MVIK) procedure. This study was conducted to determine the spatial variability and correlation of indicator parameters on a field scale with respect to soil quality and suitability for use with MVIK. The variability of the biological parameters decreased in the order of respiration> enzyme assays and qCO2 > microbial biomass C. The distribution frequency of all parameters except respiration were normal although the spatial distribution across the landscape was highly variable. The biological parameters showed little correlation with each other when all data points were considered however, when grouped in smaller sections the correlations were more consistent with observed patterns across the field. To accurately asses soil quality, and arable land use, consideration of spatial and temporal variability, soil conditions and other controlling factors must be taken into account.