Assessing Soil Health and Fertility in Organic Vegetable Farms of Green Valley Cooperative

Thesis Abstract

Organic vegetable farms are increasingly recognized for their sustainable agricultural practices and potential contributions to soil conservation; however, variations in soil health and fertility across different organic systems remain underexplored, particularly within community-based cooperatives. This study aims to assess the status of soil health and fertility in organic vegetable farms managed by Green Valley Cooperative, with the specific objectives of quantifying soil physical, chemical, and biological properties, evaluating the influence of organic amendments and crop management practices, and identifying key indicators of sustainable soil fertility. Employing a cross-sectional research design, the study integrated both quantitative and qualitative approaches to achieve comprehensive insights. The population comprised 50 active organic vegetable farm plots within the cooperative, with a stratified random sampling technique selecting 20 representative farms for detailed analysis. Data collection involved field sampling of soil properties using standardized procedures, including particle size analysis, pH measurement, organic carbon content, and microbial biomass quantification through substrate-induced respiration. Additionally, farmer interviews and questionnaires were employed to gather information on soil management practices, crop rotations, and organic input usage. Laboratory analyses utilized techniques such as Fourier-transform infrared spectroscopy (FTIR) for organic matter characterization, enzyme assays (e.g., dehydrogenase activity) for microbial activity, and atomic absorption spectroscopy for nutrient profiling. Validity and reliability of the instruments were ensured through calibration, pilot testing, and inter-laboratory comparisons. Data analysis integrated descriptive statistics to characterize soil properties, while inferential statistics—specifically analysis of variance (ANOVA)—examined differences across farms with varied management practices. Multiple regression models tested the relationships between soil management variables and soil fertility indicators, informed by the Theories of Soil Quality (Doran & Parkin, 1994) and Sustainable Agriculture Theory. Thematic analysis was applied to qualitative data to contextualize farming practices’ influence on soil health. It is anticipated that findings will reveal significant variability in soil physical, chemical, and biological attributes across the farms, with farms employing diverse organic amendments and crop rotations demonstrating superior soil health indices. The study expects to identify specific biological indicators—such as microbial biomass and enzyme activities—as sensitive, early-warning signals of soil fertility decline or improvement. These results are poised to contribute novel insights into the specific practices fostering sustainable soil conditions within community-based organic systems, filling the gaps identified in the existing literature regarding localized soil health assessments. The study's core contribution lies in establishing a comprehensive, multi-indicator soil health assessment framework tailored to organic vegetable farms within cooperative contexts, which can inform best practices and policy interventions aimed at enhancing soil fertility sustainably. The key conclusion emphasizes that sustainable organic farming in Green Valley Cooperative hinges on targeted management practices, particularly the judicious use of organic amendments and crop rotation strategies, to sustain and improve soil biological vitality and fertility. Based on these findings, the study recommends the adoption of integrated soil health monitoring protocols incorporating biological indicators, increased farmer education on organic input management, and further longitudinal research to evaluate the impacts of specific organic practices over time. The results serve as a foundation for similar assessments in comparable cooperative or smallholder organic systems, ultimately contributing to the broader understanding of sustainable soil management in organic vegetable production.