Assessment of Baye Giche Area Closure as a Strategy for Sustaining Land Productivity in Kersa Mallima District, Oromia, Ethiopia

Abstract

Land degradation is a severe environmental problem that lowers the productive capacity of land resources. This includes the degradation of vegetation cover, soil degradation, and nutrient depletion, which are major ecological problems in Ethiopia, particularly in the study area." As a response of the ever expanding land degradation, rehabilitation of degraded lands through enclosure of areas has been practiced in the study area. The purpose of this study was to assess the success of Baye Giche area closure in sustaining land productivity in terms of augmentation of soil fertility along with enhancement of plant species diversity in the Kersa Mallima District Baye Giche area closure. Soil samples were collected from 9 plots of both area closure and adjacent open grazing land. Soil samples were obtained from topsoil (0-30 cm) for soil fertility status analysis, and 18 composite soils were collected using "X" design methods with a sample plot size of 20 m X 20 m for quantitative data. The soil laboratory examinations were performed for bulk density, soil moisture, soil texture, soil pH, total Nitrogen, available Phosphorus., Organic Carbon, Electric Conductivity, Cation Exchange Capacity, Sodium Cation, Potassium Cation, Calcium Cation, and Magnesium Cation (Na+, K+, Ca+2, and Mg+2). The data were examined using an Excel spreadsheet and SPSS software. In addition, an independent t-test was used to determine the significance level. Except for soil texture class, Av.P, and K+, there were no significant variations among the investigated soil physicochemical variables. In addition to this, field survey was carried out to assess achievement of Baye Giche area closure in enhancing of plant species diversity. Based on slope of the area four hectares of land were sampled from both area closure and adjacent open grazing land on each hectares. Accordingly 36 plots or 1.44 hectares of land was sampled from area closure and adjacent open grazing land. The total density /number of individual plant species in the closed area and adjacent open grazing land was 3455/ha and 4125/hectares, respectively. The overall area closure individual density of species regeneration status were 9020/ha, 6206/ha, for both seedlings and saplings respectively. While the adjacent open grazing area’s total individual density of species regeneration were 6862/ha, 7219/ha for both seedlings and saplings respectively. The study found no significant difference in species diversity between area closure and nearby open land despite different levels of species diversity. The reasons for this include soil fertility, soil erosion, and human and animal intrusions. The study highlights how complex landscape, soil, and disturbance dynamics can obscure nominal diversity differences without contradicting ecological theory or empirical findings. Free grazing land posed a significant harm to plant species diversity. So mass management should be developed in the area to address the grazing land. This study did not assess the achievement of area closure on grasses type, structures, and their usage. Other researchers can study the effect of area closure on these characteristics to verify whether the effect is significant or not