The Effect of Smallholder Farmers’ Managed Wetlands on Plants’ Diversity and Soil Properties in Gedeo Zone, Gedeb wereda, Southern Ethiopia.

Abstract

This study was conducted in southern Ethiopia to assess the impact of smallholder farmers’ managed wetlands on plants diversity and soil properties. Vegetation data were collected from 60 plots having (1m x1m) quadrats laid on five transects lines along the altitudinal gradient. Vegeta tion data were analyzed using, descriptive statistics, Sorenson’s similarity, and Shannon-Wiener diversity index and R. 2.14 software. Sixty composite soil samples were collected at depth of 0-15 and 15-30 cm to study soil texture, pH, electrical conductivity, soil organic carbon, total nitrogen and cation exchange capacity at a distance of 1m, 100 m, 200 m and 300 m from the wetland. Moreover, 60 undisturbed soil core samples were collected to examine soil bulk density. Analysis of variance (P<0.05) was employed to test the degree of variations. Result showed 65 plant species were identified and grouped in 21 families. Of all families, Poaceae contains 12 species. The Soren son’s similarity showed highest similarity was observed between community one and two 85% and lowest similarity were observed between community one and three 28%. The highest diver sity of species was observed in community four while the highest species evenness was observed in community two. A soil bulk density (p =0.001) and EC significantly varied (p<0.001, p = 0.041 respectively) with distance from wetland. Similarly, variation was observed on silt, clay, soil bulk density and CEC (p = 0.031, p = 0.046, p<0.001 and p<0.001 respectively) along with the soil depth. The soil near the wetland has shown improvements relative to the distance treatments. The improvement in the soil properties near the wetland was due to higher soil organic matter (SOM) input and less soil disturbance.

Keywords: Soil properties, Plant diversity, and Smallholder farmers