Grazing Effects on Floristic Composition and Above Ground Plant Biomass of the Grasslands in the Northeastern Mongolian Steppes

We describe plant biomass in the grasslands of the Mongolian steppe obtained using a quadratsampling technique. Four sites were studied in the northeastern Mongolia located between 47°12'N and 47°40'Nand 102°22'E and 112°24'E, which were typical grasslands of the steppe. Biomass, carbon and nitrogen contentwere determined for the plants collected from the grazed and ungarazed stands. With the measurements above,we expect to obtain information on grazing effects on the grasslands and carbon sequestration of the grasslandfrom the air. In order to estimate the biomass without destroying the stands, we derived an equation to describethe relationship between plant biomass and v-value using plant height and species coverage within the stand.Estimated plant biomass in the ungrazed and grazed stands ranged between 108.0 g m-2 and 13.4 g m-2 andbetween 97.5 g m-2 and 14.1 g m-2 in late June 2005, respectively. Litter in the ungrazed and grazed standsranged from 330.3 g m-2 to 78.4 g m-2 and from 188.0 g m-2 to 20.3 g m-2, similarly. Average carbon and nitrogencontents in plants and in litter were 43.0% and 1.9% and 33.7% and 1.4%, respectively. In study sites atBaganuur, the carbon and nitrogen content of plant materials (plant plus litter) was 118.4 g m-2 and 4.7 g m-2on 30 June 2005.