Effect of exclosure on woody species diversity and population structure in comparison with adjacent open grazing land: the case of Jabi Tehnan district north western Ethiopia

Abstract

Land rehabilitation by area exclosure was the fastest and moderate approach of recovering degraded sites. However, the effect of exclosure on woody species parameters in Jabitehnan district, north-western Ethiopia has not been investigated. Therefore, the current study was conducted (i) to assess and compare diversity, composition and density of woody species in exclosure and adjacent open lands, and (ii) to analyze population structure as well as regeneration status of woody species. A random sampling method was employed to select a total of 40 sample plots (50m*50m). A total of 8 parallel transect lines were used inside and outside the exclosure land in each site for consecutive (50m interval) plot establishment. Species diversity was 1.7 and 3.03 for WG, 1.1 and 2.94 for GW open and exclosures, respectively. Population structure of woody species in exclosures of both sites exhibited an inverted J shape which indicates good regeneration status, while in adjacent open grazing land it exhibited partial bell shape. Generally, exclosure provides various biophysical benefits better than adjacent open grazing lands. It is recommended to protect degraded lands by exclosure via integrating appropriate species and convert their diversity into use so as to develop their potential benefits on land restoration.

Keywords

• composition
• disturbance
• diversity
• exclosure
• regeneration pattern
• rehabilitation