Climate variability a dominant driver of vegetation health dynamics in Kapchorwa district, Uganda

Abstract

Economic development, particularly in third world nations heavily reliant on agriculture, is under threat from climate change as a global phenomenon. While there have been some studies on its impact on vegetation productivity in other regions, there is a lack of research in African countries, specifically in Uganda's agricultural districts. This study aimed to evaluate the role of climate variability as a dominant factor in vegetation health in Kapchorwa district. To explore the relationships within the study, correlational research design with an integration of quantitative methods was employed. Secondary and primary climate data sets were used to determine the trends and variations in rainfall and temperature from 1989 to 2019. The Normalized Difference Vegetation Index (NDVI), Vegetation Relative Abundance, and relative abundance were employed as indicators of vegetation health, and their correlations with rainfall and temperature were examined. The results showed an increasing trend (p>0.05) in both maximum and minimum temperatures in Kapchorwa district over the 30-year period, with minimal variation. Rainfall also exhibited an upward trend (p>0.05) with high variability and relatively even distribution patterns. NDVI significantly increased from 1989 to 2019, with sporadic periods of drought in the earlier years. The district's vegetation diversity was moderate (0.47), with Poaceae (grass) being the most abundant vegetation type (57%), and Actinidiaceae (shrubs) the least abundant (46%). The strong correlation (72%) and regression coefficients (52%) indicated a significant impact of temperature on the diversity and abundance of vegetation, which are essential indicators of vegetation health. These findings emphasize that while Kapchorwa's vegetation health has generally benefited from the positive climatic trends, the diversity and distribution of vegetation types are essential considerations for sustainable management and conservation. The efforts of local governments and districts should focus on preserving the dominant species of grasses, trees, and shrubs, as they are essential for maintaining ecosystem stability. The preservation of native plant species and sustainable harvesting should be prioritized in local community conservation efforts to support and improve the current trend of healthy vegetation in the face of climate variability.