Location: Poultry Production and Product Safety Research
Title: Soil Management Assessment Framework (SMAF) in temperate and subtropical agroecosystems: A comparative analysisAuthor
AMORIM, HELEN - University Of Arkansas | |
Ashworth, Amanda |
Submitted to: Meeting Abstract
Publication Type: Abstract Only Publication Acceptance Date: 6/9/2023 Publication Date: N/A Citation: N/A Interpretive Summary: Technical Abstract: The Soil Management Assessment Framework (SMAF) was initially developed to assess soil health as affected by management practices in US agroecosystems. In recent years, SMAF has been used in Brazil to assess the impacts of conservation practices and land use changes in soil health, yet the sensitivity of soil indicators and SMAF scoring functions, as well as their relationship with ecosystem services, is not proven for tropical and subtropical regions. Here, we aimed to assess SMAF soil quality indices (SQI) in agroecosystems in Brazil and Mid-south US, and investigate the ability of SMAF to differentiate between conservation and conventional management practices and the relationship of SMAF with ecosystem services. For this, we compiled 12 peer-reviewed SMAF studies published in Brazil (n = 206) and compared to five studies published for the Mid-south US (n = 142). Descriptive statistics were computed, and the Kruskal-Wallis test was used to compare soil indicators [pH, P, K, bulk density (BD), aggregate stability, soil organic C (SOC), and microbial biomass C (MBC)] and SMAF soil quality indices between conservation and conventional agricultural practices in each region. Additionally, linear regressions were performed to assess the relationship between SMAF SQI and SOC retention. Mean SMAF SQI values varied between 59-77% and 57-72% in conservation and conventional agroecosystems in Brazil, respectively, and between 63-86% and 62-86% in conservation and conventional agroecosystems in the Mid-Southern US, respectively. Despite the overall lower BD and higher SOC content in conservation agroecosystems, SMAF SQI did not differ between conservation and conventional systems across soil depths and in both regions (p > 0.05). Yet, coefficients of determination (R2) between 0.50-0.65 indicate that SMAF SQI can be used as an indicator of SOC retention and relates to the ability of agroecosystems to provide regulating ecosystem services. The SMAF scoring functions need to be revised to effectively capture the beneficial effects of conservation practices on soil health in subtropical and tropical systems. |