Proceedings of the 2020 Mississippi Water Resources Conference

Year: 2020 Authors: Chang T., Paul V., Feng G.

Soil health assessment tools can help evaluate whether agricultural measures contribute to sustainable development. The indicators used to evaluate soil health are generally composed of soil physical (including hydrological), chemical, and biological properties. However, quantifying and integrating soil health indicators is a complex and time-consuming process. Currently, there are several methods available for assessing soil health, such as standard scoring functions (SSF) method, Cornell soil health assessment (CSHA) tool, Ontario soil health assessment method (OSHA), and soil management assessment framework (SMAF). However, some of these assessment tools have been shown to be inconsistent due to high variability in soil and climatic characteristics and the sensitivity of soil health indicators caused by different agronomic management methods. Therefore, the applicability of soil assessment methods should be evaluated locally, and include weighted calculations based on soil characteristics. This study selected three methods, SSF, CSHA, and OSHA, and included two methods of weight vector calculation: analytic hierarchy process and iterative algorithm. In total, six methods were employed to calculate the soil health scores. Soil data were obtained from a 7-year experiment conducted in the state of Mississippi, which consisted of four fertilization systems (unfertilized control, commercial inorganic N fertilizer, and pelletized poultry litter with/without flue gas desulfurization (FGD) gypsum) and two cover crop treatments (wheat winter cover crop and fallow). The objectives of this study are: 1) to quantify selected soil physical, chemical, and microbiological indicators in the upper 0-15 cm of soil; 2) to compare soil physical, chemical, and biological attributes between contrasting, innovative management practices; and 3) to assess the sensitivity of different soil health scoring methods. Preliminary analysis of soil physical, chemical, and microbial indicators in the study area showed that wheat winter cover crop and pelletized poultry litter, especially in combination with gypsum, can significantly increase soil health scores. The results are expected to determine which soil health assessment tools are more sensitive and help in showing numerical differences in soil health scores among different fertilization regimes and cover crops in the state.