Track 1-14: Implementing and Monitoring Management Strategies to Deal with Variability in Grasslands at Farm Level
Description
Management practices can increase biodiversity and generate corresponding compensatory effects on biomass production, which may reduce inter-annual variability of productivity in some grassland ecosystems. However, it remains unclear how stocking rate influences variability of ecosystem productivity. Four stocking rates were compared in a completely randomized block experiment in the desert steppe of Inner Mongolia, China: non-grazed control (0 sheep/ha/mo), lightly grazed (LG, 0.15 sheep/ha/mo), moderately grazed (MG, 0.30 sheep/ha/mo) and heavily grazed (HG, 0.45 sheep/ha/mo). Aboveground net primary productivity (ANPP) was measured every August for eight consecutive years (2004-2011). ANPP decreased significantly (P < 0.05) with increasing stocking rate. Coefficients of variation for community (CVcomm) in LG and MG were lower than in the control and HG treatments. Coefficients of variation for both species (CVsp) and functional groups (CVPFG) showed logarithmic relationships with relative density (P < 0.05). Thus, both stocking rate and annual precipitation significantly affected the biodiversity and stability of desert steppe in terms of interannual variability of ANPP. As in other grazed systems, our results indicate that grazing management can alter dominant species and functional group components within the grassland community.
Included in
Effects of Stocking Rate on the Variability of Ecosystem Productivity in Desert Steppe
Management practices can increase biodiversity and generate corresponding compensatory effects on biomass production, which may reduce inter-annual variability of productivity in some grassland ecosystems. However, it remains unclear how stocking rate influences variability of ecosystem productivity. Four stocking rates were compared in a completely randomized block experiment in the desert steppe of Inner Mongolia, China: non-grazed control (0 sheep/ha/mo), lightly grazed (LG, 0.15 sheep/ha/mo), moderately grazed (MG, 0.30 sheep/ha/mo) and heavily grazed (HG, 0.45 sheep/ha/mo). Aboveground net primary productivity (ANPP) was measured every August for eight consecutive years (2004-2011). ANPP decreased significantly (P < 0.05) with increasing stocking rate. Coefficients of variation for community (CVcomm) in LG and MG were lower than in the control and HG treatments. Coefficients of variation for both species (CVsp) and functional groups (CVPFG) showed logarithmic relationships with relative density (P < 0.05). Thus, both stocking rate and annual precipitation significantly affected the biodiversity and stability of desert steppe in terms of interannual variability of ANPP. As in other grazed systems, our results indicate that grazing management can alter dominant species and functional group components within the grassland community.
