The effect of shade species on soil macrofauna diversity and coffee yield in the coffee-based agroforestry system along an elevation gradient in South-eastern, Ethiopia

Native shade tree species protect crops from extreme weather conditions and improve their growth through enhanced soil fertility. Soil macrofauna are critical indicators for the sustainable management of agricultural ecosystems through soil fertility management and maintenance. The overall objective of this study was to evaluate the effect of shade species on soil macrofauna diversity and coffee yield in a coffee-based agroforestry system (CAFS) along an elevation gradient (1600–2000 masl) of Southeastern Sidama National Regional State, Ethiopia. The soil macrofauna diversity was evaluated using the Shannon diversity index. The harvested coffee yield bean was sundried, grinded and weighed using a digital measuring balance. Analysis of the results showed that a higher amount of soil macrofauna was recorded during the rainy season in both shade and full-sun coffee systems. Soil macrofauna diversity was high in CAFS and significantly differed ( p  < 0.001) among the studied elevations in the rainy season. The soil macrofauna diversity was highest for mid-elevation and the least for high elevation. The mean coffee yield was slightly higher for coffee grown in full-sun than in shade coffee systems. Our result indicated a strong relationship (r = 0.90; p  < 0.001) between the Shannon diversity of shade trees and soil macrofauna. The present study indicated that the shade coffee system fosters the abundance and diversity of soil macrofauna but not coffee yield. However, the abundance and diversity of soil macrofauna will help to improve soil fertility and the resilience of coffee to the impact of climate change.