Field Scale Studies on the Spatial Variability of Soil Quality Indicators in Washington State, USA

Abstract

Arable lands are needed for sustainable agricultural systems to support an ever-growing human population. Soil quality needs to be defined to assure that new land brought into crop production 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 qCO 2 > 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 assess soil quality, and arable land use, consideration of spatial and temporal variability, soil conditions, and other controlling factors must be taken into account.

County-Scale Spatial Distribution of Soil Enzyme Activities and Enzyme Activity Indices in Agricultural Land: Implications for Soil Quality Assessment

“…Knowledge regarding the spatial distribution of soil enzyme activity across the landscape has great implications for interpreting the spatial pattern of OM decomposition and the rate of nutrient mineralization at regional scales [ 23 ]. When taking biological properties as the indicator of soil quality, it is necessary to consider the spatial variability of biological properties themselves as well as the underlying influencing factors [ 24 ]. Most studies have investigated the spatial variability of soil enzyme activities based on pot and/or microplot experiments [ 25 , 26 ], while few reports are available at regional scales [ 22 – 24 , 27 – 29 ].…”

“…When taking biological properties as the indicator of soil quality, it is necessary to consider the spatial variability of biological properties themselves as well as the underlying influencing factors [ 24 ]. Most studies have investigated the spatial variability of soil enzyme activities based on pot and/or microplot experiments [ 25 , 26 ], while few reports are available at regional scales [ 22 – 24 , 27 – 29 ]. Because the experimental data are not always applicable to actual field conditions, it is necessary to carry out field studies on the spatial variability of soil enzyme activity, especially in arid and semiarid areas associated with serious soil erosion.…”

Prediction of Soil Properties at Farm Scale Using a Model-Based Soil Sampling Scheme and Random Forest

“…Several studies have demonstrated that a density of less than 1 sample per ha is able to capture the most variation in the predictors at farm scale (Debaene et al, 2014;Schmidt et al, 2014;Smith and Halvorson, 2011). Conditioned Latin hypercube sampling is a stratified random procedure that picks samples based on the distribution of predictors .…”

The assessment of land exploitation by enumerating microbial population: Case study in several locations at Dieng Plateau

“…There were tried to select test indicators. Several soil biological indicators were rejected due to the high cost of analysis, so that it only used these indicators: organic matter, active carbon, potentially mineralizable of nitrogen, and root health rating [6]; lately, an increase in the use of soil microbial parameters has occurred [7].…”