Effects of Grazing Intensity and Bush Encroachment on Herbaceous Species and Rangeland Condition in Southern Ethiopia

Abstract

Grazing intensity and bush encroachment are disturbance factors that may alter the floristic composition of herbaceous species. This paper investigates impacts of grazing (intensity) and bush encroachment on herbaceous species and rangeland conditions in Borana, southern Ethiopia. Herbaceous species richness and the abundance of each species were greater in the light‐ and moderate‐grazed areas than heavy‐grazed sampling plots. Similarly, herbaceous species richness was highest at an intermediate level of biomass and seems to decline as biomass increases. Among a total of 40 herbaceous species recorded, 20 per cent were tolerant of grazing, whereas the remaining 80 per cent were highly susceptible to heavy grazing. In both encroached and non‐encroached sampling plots, species richness varied from three to six species 0·25 m−2. Overall, herbaceous species richness and abundance, in relation to grazing gradient, might disclose a better picture of the effect of grazing on individual herbaceous species. As species richness seems to decline under heavy grazing intensity, low to intermediate grazing levels may promote and conserve key forage species in savanna grazing lands. Copyright © 2012 John Wiley & Sons, Ltd.

Estimating soil erosion risk and evaluating erosion control measures for soil conservation planning at Koga watershed in the highlands of Ethiopia

“…Studies conducted in Ethiopian highlands show that soil erosion is seen as a direct result of the historical human settlement in the highlands because of its favorable climatic conditions, political factors and soil fertility (Hurni, 1993;Keesstra et al, 2016). Inappropriate land use, poor farming practices and removal of the natural vegetation aggravate soil erosion and so productivity declines, resulting in food insecurity for smallholding farmers (Adimassu et al, 2014;Angassa, 2014;Bravo-Espinosa et al, 2014). Soil erosion is one of the biggest problems resulting in both on-site and off-site effects.…”

Predicting parameters of degradation succession processes of Tibetan <i>Kobresia</i> grasslands

“…First, their grazing can affect the structure and composition of plant community, and the constitution of plant life forms and ecotypes in alpine grasslands (de la Paix et al, 2013;Zhao et al, 2013;Mekuria and Aynekulu, 2013). Second, their trampling can reduce infiltration rates, surface sealing, and physical crust formation (Cerdà and Lavee, 1999;Angassa, 2014). With increased grazing, a part of alpine grasslands gradually degrade and become bare soil due to decreased vegetation protection (Zhang et al, 2003a, b;G.…”

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Sustainability of Climate Resilient Soil and Water Conservation Strategies Nexus the Practices in Tragedy at the Upper Blue Nile Basin of Northwestern Ethiopia: Economic Welfare Implication to the Farming Communities

“…This posed pressure on the natural resource (mainly soil, water and vegetation) resource base in many highland areas of the country [1]. Erosion causes serious land degradation and it is a global environmental problem though there are variations in the extent, depth, type and pushing factors of the problem [2][3][4].…”