中文摘要：

预言人的活动怎么将影响高山的草地的反应到未来温暖有许多无常。在这研究，有温暖控制并且抓紧的一个领域实验在北西藏在三举起(4313 m， 4513 m 和 4693 m ) 在一块高山的草地被进行测试抓紧将改变在生物资源生产上温暖效果的假设。自从 2008 年 7 月，开的最高的房间(OTC ) 被用来增加温度， OTC 由约 0.9 楴湯挠癯牥 ? 桴 ? 题传 G 整 ? 敮 ? 牰摯 ' 讟 N 楶祴眠獡瘠牥 ? 增加了空气温度潬 ? 湩㈠ ?? 潣灭牡摥琠??? 愠摮ㄠ吗？？

英文摘要：

Predicting how human activity will influence the response of alpine grasslands to future warming has many uncertainties.In this study, a field experiment with controlled warming and clipping was conducted in an alpine meadow at three elevations（4313 m, 4513 m and 4693 m） in Northern Tibet to test the hypothesis that clipping would alter warming effect on biomass production.Open top chambers（OTCs） were used to increase temperature since July,2008 and the OTCs increased air temperature by approximately 0.9o C ~ 1.8o C during the growing in2012.Clipping was conducted three times one year during growing season and the aboveground parts of all live plants were clipped to approximately 0.01 m in height using scissors since 2009.Gross primary production（GPP） was calculated from the Moderate-Resolution Imaging Spectroradiometer GPP algorithm and aboveground plant production was estimated using the surface-measured normalized difference vegetation index in 2012.Warming decreased the GPP, aboveground biomass（AGB） and aboveground net primary production（ANPP） at all three elevations when clipping was not applied.In contrast, warming increased AGB at all three elevations, GPP at the two lower elevations and ANPP at the two higher elevations when clipping was applied.These findings show that clipping reduced the negative effect of warming on GPP, AGB and ANPP, suggesting that clipping may reduce the effect of climate warming on GPP, AGB and ANPP in alpine meadows on the Tibetan Plateau, and therefore, may be a viable strategy for mitigating the effects of climate change on grazing and animal husbandry on the Tibetan Plateau.