Study On Biomass, Nutrients Of Dominant Species And Trends Of The Rumen Degradability In Old World Bluestem Shrub Rangeland

Community frame, biomass of old world bluestem(Bothriochloa Ischaemum) shrub grassland; nutrient change in different growth stages and degradability of dominant plant, such as old world bluestem(Bothriochloa Ischaemum), dahurian bushclover(Lespedeza davurica), rush lespedeza(Lespedeza inschanica), Russian wormwood(Artemisia vestita), cepitose cleostogenes(Cleistogenes caespitosa) were studied. Legume at offshoot, bud, blooming, seedpod stage; grasses at tiller stage jointing, heading, blooming, bearing stage; Compositae Artemisia vestita at return green, offshoot, bud, blooming, seedpod stage were selected.Results showed that 1 old world bluestem which mainly constitute the old world bluestem Shrub Grassland, had highest degree of dominate,sedge(Carex spp.), cepitose cleistogenes, dahurian bushclover, follows, the curve of biomass (aboveground biomass) had single peak, which appeared in August; the curve of biomass(underground biomass) had two peak, which formed in September, at the same time, the percentage of 0-10cm account for more than 80 percent total biomass was largest in September. 2. the contents of CP, Ash declined gradually, with the passing of growth stage, but contrary result appeared with ADF and NDF. The contents of CP in Legume changed markedly at bud stage. It happened in grasses at early blooming stage. 3. The dynamic curves of change in DMD and OMD of herbage sample were similar in various growth stages. 4. The more CP, the higher CPD. CPD of old world bluestem, cepitose cleistogenes at blooming stage were higher than that in heading stage, but lower in jointing stage. CPD of Russian wormwood at bud (76.13%),seedpod(67.04%) were higher than that in other stages. It is beneficial to grazing that the peak of biomass(aboveground biomass) at blooming stage in old world bluestem cespitose cleistogenes appeared in august. 5. Though there were different plants, which could be grazed by beasts in different stages from return green to wither of old world bluestem Shrub Grassland, it is most suitable for grazing in August.