Effects of grazing on the soil properties and C and N storage in relation to biomass allocation in an alpine meadow

Abstract

Livestock grazing is one of the most important factors influencing the above-ground community composition and structure in a natural grassland ecosystem. Different grazing intensities also have the potential to alter soil C and N storage substantially in grasslands. We conducted a field community study and soil analyses to determine the effects of different grazing intensities on the above-ground community and soil properties in an alpine meadow on the Tibetan Plateau. Our results showed the following: (i) the vegetation height, coverage, and above-ground biomass significantly declined with increased grazing intensity, but the species richness reached the highest level in a moderate grazing intensity meadow; (ii) grazing had a significant positive effect on soil properties in that the soil moisture content, soil organic carbon concentration, soil total nitrogen concentration, soil available nitrogen, soil total phosphorus, and soil available phosphorus significantly increased with increased grazing pressure; and (iii) soil C and N storage also significantly increased with increased grazing pressure; altogether, these increases had a significant positive correlation with the increase of below-ground biomass allocation. Our results indicated that higher grazing intensity might have a potentially positive effect to increase the soil C and N storage in alpine meadows. However, from a long-term perspective, moderate grazing may help to achieve a balance between species diversity protection, livestock production and soil C and N management.

Management of Grazing Intensity in the Semi‐Arid Rangelands of Southern Australia: Effects on Soil and Biodiversity

“…There are well-documented positive effects of woody cover on SOC (Tighe et al, 2009;Li et al, 2011;Simón et al, 2013;Pulido-Fernández et al, 2013;Kurgat et al, 2014) and associated benefits of increased infiltration and soil stability (Daryanto & Elderidge, 2010). Kurgat et al (2014) reported 0·41% higher levels of SOC under shrubs compared with bare ground, and Belay & Kebede (2010) found 0·38 to 0·23% perennial grasses.…”

“…Overgrazing is recognized as an important factor in rangeland degradation, but there is a lack of unanimity for the effects of livestock grazing on soil C. Some recent studies show a decrease (Su et al, 2004;Zuo et al, 2008;Mofidi et al, 2012), no significant change (Sanjari et al, 2008;Allen et al, 2013;Lu et al, 2015) or an increase in soil C (Reeder & Schuman, 2002;Li et al, 2011). These inconsistencies are due to differences in plant species composition (Piñeiro et al, 2010), the legacy of previous management and interactions between these factors.…”

Soil property variations in relation to exclosure and open grazing land use types in the Central Rift Valley area of Ethiopia

“…Livestock overgrazing is one of the most important factor that results in grassland degradation, soil erosion and nutrient losses (Wei et al 2011). Due to overgrazing, the natural vegetation in the northern highlands of Ethiopia has virtually disappeared, leaving degraded communal grazing lands with irregularly spaced trees and shrubs and vast areas of bare lands devoid of vegetation (Nedessa et al 2005).…”

Modeling impacts of climate change and grazing effects on plant biomass and soil organic carbon in the Qinghai–Tibetan grasslands

“…Thus, some studies showed that the grazing intensity and SOC had a negative correlation (Derner et al, 1997;Bagchi and Ritchie, 2010;Wu et al, 2009) or no relationship (Milchunas and Lauenroth, 1993;Holt, 1997). By contrast, many other studies showed that grazing can increase the SOC (Schuman et al, 1999;Wienhold et al, 2001;Li et al, 2011). This is partly because moderate grazing can increase the grassland belowground biomass, which is beneficial for the accumulation of SOC (López-Mársico et al, 2015;Hafner et al, 2012).…”