E3 Journal of Agricultural Research and Development

E3 Journal of Agricultural Research and Development Vol. 2 (4) pp. 096-100, November 2012; © E3 Journals; ISSN 2276-9897

Herbage yield, species diversity and quality of native grazing land vegetation under sub humid climatic conditions of Western Ethiopia

Abstract

This survey was undertaken in Mendi district of West Wollega Zone and aimed to identify frequently occurring species, and variation of study sites in terms of herbage dry matter (DM) yield and quality traits. Five sites were sampled to determine botanical composition, herbage yield, species diversity, crude protein (CP), neutral detergent fibre (NDF) and in vitro organic matter digestibility (IVOMD). Overall, 20 species were identified (19 were herbaceous species and one was a dwarf perennial shrub). Out of the 19 species, eight were perennial graminoid, one was annual graminoid and the rest were annual non-graminoid species. Hyparrhenia rufa, Pennisetum polystachyon and Brachiaria humidicola were observed to be dominant. Location significantly (P<0.05) affected herbage yield, while intra-location transect position did not (P>0.05). Mean herbage DM yield values ranged between 0.86±0.39 kg m-2 and for Guyo Tayiba site to 3.40±0.39 kg m-2for Idoro Tobara site. Species richness ranged from 3±0.67 to 4±0.67, but between- and within-location values did not vary significantly (P>0.05). Between-and with-in location differences were not significant (P>0.05) for diversity. Evenness ranged from 1.21±0.54 to 2.26±0.54. The mean CP, NDF and IVOMD were 6.17±1.27%, 75.89% and 48.44%, respectively. Based on values of species diversity, yield and quality, the studied grassland was found to be poor.

Keywords: Evenness; species richness; Shannon diversity index; herbage quality