Effects Of The Different Grazing Intensity On Greenhouse Gas Fluxes Of Inner Mongolia Grassland

The experiment was conducted to reveal the contribution of greenhouse gas emission in Inner Mongolia to the global warming under the background of global climate changing. The grazing experiments were carried out on the representative meadow steppe, typical steppe and desert steppe. The grazing experiments in desert steppe are small-scaled; the grazing experiments in typical steppe and meadow steppe were the family ranch-based large-scaled. More popular through the international static box - weather chromatography and based on wavelength scanning cavity ring-down spectroscopy of the G1301 field measurements of trace gases were used in this experiement. Experiments were conducted from July 2009 to August 2010. The results were shown as follows:1. Desert steppe ecosystem in Inner Mongolia, undisturbed grassland under different grazing intensities, completely bare the direction of the original gas fluxes and seasonal variations of the exchange had not changed. Desert grassland ecosystem was CH₄ sink and CO₂ source. N₂O showed out change from time to time, as the double flux exchange model of the source and sink. The mean of annual emissions is source, moderate-grazing is the biggest(2.15μg·m^-2·h^-1), the light-grazing is the weakest(0.73μg·m^-2?h^-1). The light-grazing can reduce N₂O emissions.2. Desert grassland ecosystems in Inner Mongolia, by comparing the measured carbon exchange of greenhouse gases, showed that the total output of desert steppe C factor.3. Grazing did not change the direction of the original grass greenhouse gas exchange in the meadow steppe ecosystem of Inner Mongolia, but changed the original exchange strength. Meadow steppe in Inner Mongolia was the CH₄ sink and source of CO₂ emissions. Temperature and greenhouse gas exchange had a correlation.4. Different grazing intensity changed the original strength of the grass gas exchange in the Inner Mongolia steppe ecosystems, but did not change the direction of the original grassland gas exchange. The typical grassland of Inner Mongolia was CH₄ sink and source of CO₂ emissions. Sample temperature and gas exchange were correlated.5. Ability of gas exchange in the meadow steppe was higher than the steppe. CH₄ is lower 29%,CO₂ is higher 58%.