Construction of Soil Conservation Structures for improvement of crops and soil productivity in the Southern Ethiopia

Abstract

Soil erosion is one of the major agricultural problems in the highlands of Ethiopia. Deforestation, overgrazing, and cultivation of slopes not suited to agriculture together with the farming practice that do not include conservation measures are the major causes for soil erosion in much of Ethiopia's highland areas. Degraded soils are also the major constraints to agricultural production and food security in the Southern Ethiopian highlands. A study was conducted on watershed that covers 544 ha at Gununo area of Wolaita Zone in the Southern Ethiopia with the objective of conserving soils by constructing soil conservation measures. The soil conservation measures were implemented fully with the participation of farmers. A survey was conducted and soil erosion and fertility decline were identified as top priority problems of the watershed. Then discussion was made among PAs leaders, researchers, and the community about the solution and soil conservation measures were constructed and bund stabilizers (Elephant grasses) were planted by collective action. Continuous participatory monitoring and evaluation was made for maintenance of the structure, improvement of soil fertility, and observation of its effect on crop yields. Soil and crop data were collected after implementation of conservation measures and compared with the baseline information. A total of 9965 m soil conservation structures were constructed, out of which 66.9% and 30.5% are Fanya-juu and soil bund, respectively. The soil conservation measures adapted well to the local conditions and protected the soil from being eroded. The colour of the soil was changed to black and organic matter content was increased. Yield was increased by 22 % on some farms and 15 fold on other farms within one year of bund/fanya-juu construction and by >50 % after 3 years with similar farming practices. The land that could not grow any crop yielded 800 kg/ha of haricot bean after implementation of soil conservation measure. The purchasing power of the farmers increased after they conserved their soil. In conclusion, construction of soil conservation measures in the degraded highlands and stabilizing with multipurpose plant species is very important to conserve the soil and increase crops yields.

Key words: Soil conservation measures, Degraded soils, Soil erosion