祁连山东段南麓高寒嵩草草甸群落特征变化及其与家庭牧场管理的关系OA北大核心CHSSCDCSTPCD

The study selected the key steady stages of alpine Kobresia meadow under the same geographical and climatic to conduct field investigation and questionnaire survey on the characteristics of plant communities and economic characteristics of pastures in the Northeast Qing-Tibet Plateau.The reasons and motivations for overgrazing in those pastures were discussed based on the characteristics of plant communities in pastures and income and consumption of those families.The results showed that:(1)More than 50％of herdsmen in the study area controlled the meadow in the succession stage with Kobresia pygmaea as dominant species.The income/investment showed a slow fluctuating decline trend with grazing intensity increasing.In this process,the highest point of the income/investment appeared in Gramineae-Kobresia humilis meadow steady stage,the lowest point appeared in the K.humilis meadow steady stage,and the medium level(1.69-1.74)appeared in K.pygmaea meadow steady stage.With grazing intensity increasing,the forage production capacity of the meadow first slowly decreased and then rapidly decreased,and the succession stage with K.pygmaea as dominant species had relatively medium forage production((129.1±28.3)g/m2).2)Herdsmen's grazing management objectively controlled the capacity of plant community production in stability among different years,and higher stability of the forage production was appeared in the succession stage with K.pygmaea as dominant species(interannual variation coefficient of total aboveground biomass was 19.9％).3)Overgrazing could lead to the reduction of vegetation production and service capacity,so in order to maintain a high level of ecosystem ecological service value required the sacrifice of a part of pasture economic income,and the government compensation for family occupied only 0.06％—1.25％of the total income in the same area with no difference between the succession stages,therefore the combined result of these facts led to weaken the motivation of herders to improve the ecological service function in pastures.Thus,the vast majority of herders controlling the meadows in the stage of K.pygmaea meadow was a result of tradeoff in the health of the meadow and the income of the family.Considering the existing forage production and management mode of pasture,restoring pastures to a highest ecological service function could help achieve a win-win situation between its economic and ecological value,and based on the characteristics of meadows,we should rely on the innovation of technology and management to realize the matching degree between the means of production,production relations and productivity of plant communities,and increase the added value of meadows per unit area,then fundamentally realize the sustainable development and utilization of the meadows.