生态环境学报2018，Vol.27Issue(6)：1000-1004,5.DOI:10.16258/j.cnki.1674-5906.2018.06.002
藏北高原高寒草甸光能利用效率对增温增水的响应
Effect of Experimental Warming and Increased Precipitation on Light Use Efficiency of An Alpine Meadow in the Northern Tibetan Plateau
摘要
Abstract
Quantifying the response of light use efficiency to experimental warming and increased precipitation is a key component of global carbon cycling. A field warming and increased precipitation experiment was conducted in an alpine meadow in the Northern Tibetan Plateau since June, 2014. The field experiment was based on a complete factorial design with nine treatments and each factor had three levels (zero, low- and high-level). Two heights (40 cm and 80 cm) of open top chambers (OTC) were installed to obtain the two magnitudes of warming, and the low- and high-level warming treatments increased daily minimum air temperature by 0.34 ℃ and 1.11 ℃, respectively. Two diameters (approximately 44 cm and 62 cm) of precipitation collection funnels with rubber tubing (2 cm inner diameter) were installed to obtain the two magnitudes (15% and 30%) of increased precipitation. Observed vapor pressure deficit and daily minimum air temperature was used to simulate light use efficiency during the growing season in2014-2016. The light use efficiency algorithm used in this study was based on the Moderate Resolution Imaging Spectroradiometer light use efficiency model. Experimental warming had significant effects on daily minimum air temperature (F=39.10, P=0.000), vapor pressure deficit (F=47.45, P=0.000) and light use efficiency (F=4.20, P=0.032). In contrast, increased precipitation had significant effect on vapor pressure deficit (F=5.72, P=0.012). The effect of warming on light use efficiency showed a quadratic relationship with warming magnitude, and a negative linear relationship with the effect of warming on vapor pressure deficit. Increased precipitation had no obvious effect on light use efficiency. The effect of increased precipitation on light use efficiency showed a negative linear relationship with the effect of increased precipitation on vapor pressure deficit. Therefore, increased precipitation likely has no obvious effect on light use efficiency, whereas warming effect on light use efficiency varies with warming magnitudes in alpine meadows in the Northern Tibetan Plateau.关键词
增温幅度/增水幅度/青藏高原/高寒草地Key words
warming magnitude/increased precipitation magnitude/Tibetan Plateau/alpine grassland分类
农业科技引用本文复制引用
沈振西,张豪睿,孙维,李少伟,付刚,余成群..藏北高原高寒草甸光能利用效率对增温增水的响应[J].生态环境学报,2018,27(6):1000-1004,5.基金项目
国家重点研发计划项目(2017YFA0604801) （2017YFA0604801）
国家自然科学基金项目(31600432) （31600432）
生态系统网络观测与模拟重点实验室青年创新研究团队项目(LENOM2016Q0002) （LENOM2016Q0002）
中国科学院"西部之光人才计划"(藏北高原高寒草甸牲畜承载力对气候变化和放牧的响应) （藏北高原高寒草甸牲畜承载力对气候变化和放牧的响应）
西藏自治区自然科学基金项目(西藏高寒草甸物种丰富度和地上生物量对增温的响应) （西藏高寒草甸物种丰富度和地上生物量对增温的响应）
西藏草业重大专项(2015ZDKJZC （）
2016ZDKJZC （）
2017ZDKJZC) （）
