Increased precipitation has stronger effects on plant production of an alpine meadow than does experimental warming in the Northern Tibetan Plateau

Publication date: 15 February 2018
Source:Agricultural and Forest Meteorology, Volume 249
Author(s): Gang Fu, Zhen-Xi Shen, Xian-Zhou Zhang
The Tibetan Plateau is overall getting warmer and wetter, whereas the relative responses of plant growth to warming and increased precipitation are not fully understood. Therefore, a field warming (control, low- and high-level) and increased precipitation (control, low- and high-level) experiment was conducted to compare the relative effects of warming and increased precipitation on the normalized difference vegetation index (NDVI), soil-adjusted vegetation index (SAVI), aboveground biomass (AGB) and gross primary production (GPP) in an alpine meadow in the Northern Tibetan Plateau since June 2014. The low- and high-level experimental warming significantly decreased soil moisture (SM) by 0.02m³m⁻³ and 0.04m³m⁻³, but significantly increased air temperature (Ta) by 1.91°C and 3.51°C, respectively, across the three growing seasons in 2014–2016. The low- and high-level warming did not significantly affect NDVI, SAVI, AGB and GPP across the three growing seasons in 2014–2016. The low- and high-level increased precipitation did not significantly affect Ta, but significantly increased SM by 0.02m³m⁻³ and 0.03m³m⁻³, respectively, across the three growing seasons in 2014–2016. The high-level increased precipitation significantly increased NDVI by 18.7%, SAVI by 18.4%, AGB by 11.4% and GPP by 25.0%, whereas the low-level increased precipitation only tended to increase NDVI by 9.8%, SAVI by 8.2%, AGB by 6.2% and GPP by 12.9%. Therefore, increased precipitation had stronger effects on NDVI, SAVI, AGB and GPP than did experimental warming in this alpine meadow site of the Northern Tibetan Plateau.



from # All Medicine by Alexandros G. Sfakianakis via alkiviadis.1961 on Inoreader http://ift.tt/2z4Zas4