Track 1-13: Monitoring and Managing Grass and Forage Biomass Resources at the Landscape Level
Description
Grasslands have experienced dramatic shifts in structure and functioning driven primarily by human disturbances and global climate change. The long-term grazing has resulted in widespread declines in biodiversity and ecosystem functioning and services. This is triggered by the direct and indirect effects of grazing and often mediated by the complex interactions between vegetation and environmental. Thus, it is critical to obtain a better understanding of how grazing, abiotic factors and biotic–abiotic interactions influence key properties of ecosystem functioning and sustainability and thereby provide guideline for improving grassland management practices in the Eurasian steppe. While abundant evidence demonstrates that heavy grazing alters the ecosystem structure and function of grass- lands, research on how grazing specifically affects ecosystem functioning and stoichiometry on broad scales is scarce because of a lack of adequate ungrazed reference sites.
We examined the effects of grazing on ecosystem functioning and C:N:P stoichiometry along the 700 km China–Mongolia transect (CMT) using consistent methods. The CMT, which covers a wide range of biotic and abiotic conditions, enables us to observe the total effects of multiple mechanisms that probably operate simultaneously but vary in their relative strengths across regions. The key research questions we are trying to address are: 1) How has grazing affected ecosystem functioning (i.e. species richness, above- and below-ground biomass and litter biomass) and C:N:P stoichiometry of grasslands along the regional precipitation gradient during the last 50 years? 2) How do the responses of plant and soil C, N and P pools and stoichiometry to grazing differ among community types? 3) What is the relative importance of plant functional group (PFG) composition and species plasticity in influencing ecosystem functioning and stoichiometry?
Included in
Grazing Alters Ecosystem Functioning and C:N:P Stoichiometry of Grasslands along a Regional Precipitation
Grasslands have experienced dramatic shifts in structure and functioning driven primarily by human disturbances and global climate change. The long-term grazing has resulted in widespread declines in biodiversity and ecosystem functioning and services. This is triggered by the direct and indirect effects of grazing and often mediated by the complex interactions between vegetation and environmental. Thus, it is critical to obtain a better understanding of how grazing, abiotic factors and biotic–abiotic interactions influence key properties of ecosystem functioning and sustainability and thereby provide guideline for improving grassland management practices in the Eurasian steppe. While abundant evidence demonstrates that heavy grazing alters the ecosystem structure and function of grass- lands, research on how grazing specifically affects ecosystem functioning and stoichiometry on broad scales is scarce because of a lack of adequate ungrazed reference sites.
We examined the effects of grazing on ecosystem functioning and C:N:P stoichiometry along the 700 km China–Mongolia transect (CMT) using consistent methods. The CMT, which covers a wide range of biotic and abiotic conditions, enables us to observe the total effects of multiple mechanisms that probably operate simultaneously but vary in their relative strengths across regions. The key research questions we are trying to address are: 1) How has grazing affected ecosystem functioning (i.e. species richness, above- and below-ground biomass and litter biomass) and C:N:P stoichiometry of grasslands along the regional precipitation gradient during the last 50 years? 2) How do the responses of plant and soil C, N and P pools and stoichiometry to grazing differ among community types? 3) What is the relative importance of plant functional group (PFG) composition and species plasticity in influencing ecosystem functioning and stoichiometry?
