Effect of Cropping Systems on Soil Invertebrates Diversity and Abundance Around Kakamega Forest in Kenya
Author(s): Andrew Lyani, Muyekho N Francis, Ndonga Millicent
Soil invertebrate abundance and diversity are known to increase or maintain the fertility of soil in agricultural farms. In Western Kenya the effects of cropping systems on soil invertebrates not well documented. The objective of the study was to assess the effects of cropping systems on soil invertebrate diversity and abundance. The research was undertaken on farms around Kakamega Forest in Kenya. Forest acted as control. The cropping system treatments include pure maize, pure beans, pure tea and pure sugar cane farm and maize/beans intercrop. A Complete Randomized Design (CRD) with nine replicates for every treatment was used. Soil samples were collected and extraction of soil invertebrates done using Berlese tullgren funnel. Determination of the diversity and abundance of soil invertebrates was done using Shannon diversity index computed using the R version 2.10.0 and Kruskal- Wallis test. The forest had the highest diversity (H=2.81) for both wet and dry season followed by maize cropping system (H=2.29) and the last was in bean farm (H= 1.78). A total of 1,215 individual soil invertebrates belonging to 29 species were collected. Overall, the highest abundance was recorded in maize farm (286) followed by the forest (283) while the least was recorded at the sugar plantation (83).