In order to understand whether or not the response of vegetation indices and biomass production to warming varies with warming magnitude,an experiment of field warming at two magnitudes was conducted in an alpine mead...In order to understand whether or not the response of vegetation indices and biomass production to warming varies with warming magnitude,an experiment of field warming at two magnitudes was conducted in an alpine meadow on the northern Tibetan Plateau beginning in late June,2013.The normalized difference vegetation index（NDVI）,green normalized difference vegetation index（GNDVI） and soil adjusted vegetation index（SAVI） data were obtained using a Tetracam Agricultural Digital Camera in 2013–2014.The gross primary production（GPP） and aboveground plant biomass（AGB） were modeled using the surface measured NDVI and climatic data during the growing seasons（i.e.June–September） in 2013–2014.Both low and high warming significantly increased air temperature by 1.54 and 4.00°C,respectively,and significantly increased vapor pressure deficit by 0.13 and 0.31 kP a,respectively,in 2013-2014.There were no significant differences of GNDVI,AGB and ANPP among the three warming treatments.The high warming significantly reduced average NDVI by 23.3%（-0.06）,while the low warming did not affect average NDVI.The low and high warming significantly decreased average SAVI by 19.0%（-0.04） and 27.4%（-0.05）,respectively,and average GPP by 24.2%（i.e.0.21 g C m^（-2） d^（-1）） and 44.0%（i.e.0.39 g C m^（–2） d^（-1））,respectively.However,the differences of the average NDVI,SAVI,and GPP between low and high warming were negligible.Our findings suggest that a greater drying may dampen the effect of a higher warming on vegetation indices and biomass production in alpine meadow on the northern Tibetan Plateau.展开更多
基金National Natural Science Foundation of China(31600432)National Key Research Projects of China(2016YFC0502005+3 种基金2016YFC0502006)Chinese Academy of Science Western Light Talents Program(Response of livestock carrying capability to climatic change and grazing in the alpine meadow of Northern Tibetan Plateau)the Science and Technology Plan Projects of Tibet Autonomous Region(Forage Grass Industry)the National Science and Technology Plan Project of China(2013BAC04B01,2011BAC09B03,2007BAC06B01)
文摘In order to understand whether or not the response of vegetation indices and biomass production to warming varies with warming magnitude,an experiment of field warming at two magnitudes was conducted in an alpine meadow on the northern Tibetan Plateau beginning in late June,2013.The normalized difference vegetation index（NDVI）,green normalized difference vegetation index（GNDVI） and soil adjusted vegetation index（SAVI） data were obtained using a Tetracam Agricultural Digital Camera in 2013–2014.The gross primary production（GPP） and aboveground plant biomass（AGB） were modeled using the surface measured NDVI and climatic data during the growing seasons（i.e.June–September） in 2013–2014.Both low and high warming significantly increased air temperature by 1.54 and 4.00°C,respectively,and significantly increased vapor pressure deficit by 0.13 and 0.31 kP a,respectively,in 2013-2014.There were no significant differences of GNDVI,AGB and ANPP among the three warming treatments.The high warming significantly reduced average NDVI by 23.3%（-0.06）,while the low warming did not affect average NDVI.The low and high warming significantly decreased average SAVI by 19.0%（-0.04） and 27.4%（-0.05）,respectively,and average GPP by 24.2%（i.e.0.21 g C m^（-2） d^（-1）） and 44.0%（i.e.0.39 g C m^（–2） d^（-1））,respectively.However,the differences of the average NDVI,SAVI,and GPP between low and high warming were negligible.Our findings suggest that a greater drying may dampen the effect of a higher warming on vegetation indices and biomass production in alpine meadow on the northern Tibetan Plateau.
