The Study On NPP Simulation In Inner Mongolia And The Livestock Management In Xilinhot City

Based on the time-series NOAA/AVHRR_NDVI from 1982 to 2003 and MODIS_NDVI data from 2002 to 2004, integrated with the meteorological data and the sun radiation data, In this paper Inner Mongolia grassland's net primary production (NPP) in growing season is simulated with the modified CASA model, and the spatio-temporal change and distribution of IPAR, light use efficiency (e), and NPP are analyzed;the Animal carrying capacity of grassland in the countries of Xilinhot City is simulated by the GRAZFEED model.The study on grassland NPP shows that:(1) The IPAR and e of grass in growing season has variety in season and different regional characteristics. The IPAR and e form April to October has a single peak, and decreases from the Northeast to West south in Inner Mongolia in space scale.(2)There are differences in light use efficiency (e) value among different grass types. The e value of aerate Low-land Meadow Type is, the maximum among;temperate Desert type is 0.189 gC MJ"1, which is the minimum.temperate Low-land Meadow Type is, the maximum among all the grass typs, 0.287 gC MJ"1;The(3) The total NPP of Inner Mongolia grassland in growing season is 24. 63 TgC (1 Tg=1012 g). The NPP increased from 1982 to 1998, and decreased from 1999 to 2003 contrasted with that in early 90s. The annual variety of NPP is large since 1982.The study on livestock management in Xilinhot city shows that:(1) The production of these animals is not being limited by the concentration of protein in their diet from April to October, which is indicated by the surplus in the intake of rumen degradable protein and un-degraded protein.(2) Under no extra supplements circumstance, the weight of Ujumqin Sheep will respectively decrease about 51 g, 56 g, and 20 g each day from April to June;and it respectively increases about 7g^ 8g^ llg each day from July to September;And they will lose weight about 26g each day in October.(3)The temperature effect on the weight of Ujumqin Sheep is obvious in April and October;and it is necessary to increase the supplement to decrease the cold effect on the weight of Ujumqin Sheep.(4)The actual animal number is larger than the grassland's carrying capacity except Dabxiltu Sumu in Xilinhot city where the animal numbers in Dabxiltu Sumu can increase from May to September.