Effect Of Seasonal Use On Productivity In Typical Grassland

In growing season of2012-2013, by studying the effect of seasonal grazing-use on Leymus chinensis+Cleistogenes squarrosa+Stipa krylovii community in typical grassland of semi-arid area Xilinhhot, Inner Mongolia.We can draw the conclusion that:1Treatments T1and T3showing the highest aboveground net primary production(ANPP) and sheep intake biomass are the two optimal grazing method,both higher than the ungrazed treatment(TO).Treaatments T2and T4show the lowest ANPP and sheep intake biomass,both lower than TO.2Seasonal grazing can trigger the over-compensatory growth, just as the T1and T3show.But the treatments T2and T4show under-compensatory growth.3Seasonal grazing does not change the root biomass in different treatments significantly.The total root biomass shows a different trend in different treatments in two years.TO and T1show a decline in total root biomass in the two years but T2,T3,T4trend to increase.4The root biomass enriched in the low soil layer,especially in the0-30cm depth in T1,T3and T4,but the treatment TO shows a decline and treatment T2trend to increase in almost every soil layer.5Seasonal graze flats the seasonal curve of the soil co2flux,but does not change the seasonal and daily trend compared with T0.