Effectiveness of exclosures to restore degraded soils as a result of overgrazing in Tigray, Ethiopia

Effects of grazing exclusion on carbon sequestration and plant diversity in grasslands of China—A meta-analysis

“…AM = alpine meadow; AS = alpine steppe, TS = temperate steppe; TDS = temperate desert-steppe. tem carbon stocks induced by grazing exclusion can meet the need to restore land degradation (McIntosh and Allen, 1998;Conant and Paustian, 2002;Mekuria et al, 2007;Mekuria and Veldkamp, 2012;Zhou et al, 2007), but are inconsistent with studies carried out in grasslands with little disturbance, for example, in the U.S. (Schuman et al, 1999;Reeder and Schuman, 2002;Derner et al, 2006). By comparing our case with the above studies, we deemed that the positive effects of grazing exclusion were dependent on widespread degradation of grasslands and lower baseline of observed indicators.…”

“…Second, the wide use of animal excrement for fuel energy by local herders decreased the carbon return from livestock animal manure was used for fuel energy by local herders (He et al, 2009;Xu et al, 2013). In addition, the significant increases in plant coverage leads to less soil surface being directly exposed to wind erosion in fenced sites, which could prevent the SOC loss caused by soil erosion in grasslands (Mekuria et al, 2007). Moreover, excluding livestock stamping enhanced soil aggregate structure in fenced sites, then weakened SOM decomposition and protect the soil from water and wind erosion (Belnap, 2003;Neff et al, 2005).…”

“…Livestock grazing is a pivotal issue affecting plant growth, species diversity and soil carbon accumulation in grasslands (Olff and Ritchie, 1998;Watkinson and Ormerod, 2001;Piñeiro et al, 2010;McSherry and sity. For carbon sequestration, some studies found that grazing exclusion facilitated vegetation recovery, increased plant productivity and thus enhance soil carbon stocks in degraded grasslands (Biondini et al, 1998;McIntosh and Allen, 1998;Li et al, 2008;Mekuria et al, 2007;Mekuria and Veldkamp, 2012;Xiong et al, 2014). Others, however, reported no change (McNaughton et al, 1998;Pucheta et al, 2004) or even decline of carbon stocks in grasslands (Schuman et al, 1999;Leriche et al, 2001;Frank et al, 2002;Wienhold et al, 2001).…”

“…For example, Derner and Schuman (2007) synthesized data from the North American Great Plains and found that soil carbon stocks were lower in un-grazed than in grazed sites in areas with mean annual precipitation (MAP) of 600 mm or less. In contrast, in central Asia or Africa, many studies found positive effects of grazing exclusion on soil organic carbon (SOC) at sites with MAP less than 600 mm (Su et al, 2005;Wu et al, 2008;Mekuria et al, 2007;Mekuria and Veldkamp, 2012). For plant diversity, the results are also conflicting.…”

Stand Structure, Diversity and Regeneration Status of Woody Species in Open and Exclosed Dry Woodland Sites around <i>Molapo</i> Farming Areas of the Okavango Delta, Northeastern Botswana

“…Past studies in other countries have indicated that due to disturbance in the forests, condition shave become unfavorable for existing species, which, as a result, fail to reestablish themselves (Singh & Singh, 1992). One of the cheapest and convenient methods employed to restore, manage and conserve woody species is the establishment of area exclosures (also referred to as area enclosures or enclosures) (Birhane et al, 2004(Birhane et al, , 2006Mengistu et al, 2005a, b;Hailu et al, 2006;Mekuria et al, 2007;Teketay et al, 2010). Area exclosure is the practice of land management that involves the exclusion of livestock and humans from openly accessing an area that is characterized by severe degradation (Aerts et al, 2009;Teketay et al, 2010).…”