| 英文摘要： |
Analysis of spatiotemporal variations in forest ecohydrological characteristics is critical for understanding the impacts of climate change on forest ecological functions. In this study, using gross primary productivity (GPP), ecosystem water balance residual (eWBR) and ecosystem water use efficiency (eWUE) as forest ecohydrological function indices, and annual mean precipitation (MAP) and temperature (MAT) as climate indicators, we assessed the impacts of climate change on forest ecosystem in the Lancang-Mekong Region (LMR) during 19922016 (baseline) and 2020-2099 under different Representative Concentration Pathway (RCP) climate scenarios. The coupled Carnegie-Ames-Stanford Approaches-Gramineous Crop Growth (CASA-GRAMI) model, the Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) model, and the Hargreaves-Sumani method were employed to estimate GPP, eWBR, evapotranspiration (ET) and eWUE. The main findings are as follows: (i) GPP, eWBR and eWUE showed an increasing trend in the western parts of LMR during 1992-2099, with high values in the central and south-west of Myanmar, west and south of Thailand; (ii) eWBR decreased in most scenarios; while eWUE increases under RCP 2.6 scenario during 2030's (0.15 gC.kg(-1).H2O.yr(-1)) and 2050's (0.13 gC.kg(-1).H2O. yr(-1)) and slightly increases with a trend of 0.02 gC.kg(-1).H2O.yr(-1)) under RCP 8.5 scenario during 2050's; (iii) evergreen and deciduous broadleaved forests exhibit high GPP values, while deciduous broadleaved forest was characterized by lowest eWBR and declining trends in eWUE in future scenarios; (iv) MAT significantly correlated with GPP, eWBR and eWUE (R-2 >0.70) while MAP indicated a week correlation with GPP and eWUE (R-2 <0.50) in all the RCPs scenarios, which indicating that water-carbon cycles coupled with hydrothermal conditions may be a key control factor for carbon sequestration in LMR in the context of climate change. |
在线留言
联系我们
所长信箱