The net primary productivity (NPP) of global terrestrial vegetation is estimated by an Atmosphere-Vegetation Interaction Model (AVIM). AVIM consists of two intercoupled components: physical processes, involving water ...The net primary productivity (NPP) of global terrestrial vegetation is estimated by an Atmosphere-Vegetation Interaction Model (AVIM). AVIM consists of two intercoupled components: physical processes, involving water and energy transfer among soil, vegetation and the atmosphere at the land surface and eco-physiological processes, i.e. photosynthesis, respiration, dry matter allocation, littering, phenology. Globally vegetation is classified into 13 types and soil texture is classified into 6 types. The estimated NPP for different vegetation types at 1637 sites are validated with the observed data provided by EMDI. The main results of NPP estimation show that global averaged NPP is 405.13 g C m(-2)yr(-1), varying from 99.58 g C m(-2)yr(-1) (tundra) to 996.2 g m(-2)yr(-1) (rainforest). Global total annual NPP is about 60.72Gt C yr(-1), in which the maximum part, about 15.84 Gt C yr(-1), accounting for 26.09% of the total is contributed by tropical rainforest. The maximum carbon sink occurs in the temperate region of the Northern Hemisphere. The global spatial and seasonal distribution of terrestrial NPP is estimated reasonably.展开更多
The coupled models of both the Global Ocean-Atmosphere-Land System （GOALS） and the Atmosphere- Vegetation Interaction Model （GOALS-AVIM） are used to study the main characteristics of interannual variations. The si...The coupled models of both the Global Ocean-Atmosphere-Land System （GOALS） and the Atmosphere- Vegetation Interaction Model （GOALS-AVIM） are used to study the main characteristics of interannual variations. The simulated results are also used to investigate some significant interannual variability and correlation analysis of the atmospheric circulation and terrestrial ecosystem. By comparing the simulations of the climate model GOALS-AVIM and GOALS, it is known that the simulated results of the interannual variations of the spatial and temporal distributions of the surface air temperatures and precipitation are generally improved by using AVIM in GOALS-AVIM. The interannual variation displays some distinct characteristics of the geographical distribution. Both the Net Primary Production （NPP） and the Leap Area Index （LAI） have quasi 1-2-year cycles. Meanwhile, precipitation and the surface temperatures have 2-4- year cycles. Conditions when the spectrum density values of GOALS are less than those of GOALS-AVIM, tell us that the model coupled with AVIM enhances the simulative capability for interannual variability and makes the annual cycle variability more apparent. Using Singular Value Decomposition （SVD） analysis, the relationship between the ecosystem and the atmospheric circulation in East Asia is explored. The result shows that the strengthening and weakening of the East Asian monsoon, characterized by the geopotential heights at 500 hPa and the wind fields at 850 hPa, correspond to the spatiotemporal pattern of the NPP. The correlation between NPP and the air temperature, precipitation and solar radiation are different in interannual variability because of the variation in vegetation types.展开更多
A two-way coupling simulation from the NCAR's regional climate model REGCM2 (called R-2 hereafter) and the SUCROS model for crop growth developed by the Wageningen Agricultural University,the Netherlands (both mod...A two-way coupling simulation from the NCAR's regional climate model REGCM2 (called R-2 hereafter) and the SUCROS model for crop growth developed by the Wageningen Agricultural University,the Netherlands (both models,when in combination,denoted as R/S) are carried out on the interactions between crops and atmosphere in the Huang-Huai-Hai Plain in East China. Evidence suggests that the R/S simulations can depict pretty well the dynamic biology-based interactions between the factors,revealing reasonably both the day-to-day variations in leaf area index (LAI) and land surface physics therein,and particularly the improvement of the simulation, independently by use of the R-2,of summer precipitation and surface temperature in the research region.As a result,the present research is of significance to the further understanding of the interaction between the climate system and the terrestrial ecological systems.展开更多
基金This study was supported by National Key Basic Research Development Program (G1999043400).
文摘The net primary productivity (NPP) of global terrestrial vegetation is estimated by an Atmosphere-Vegetation Interaction Model (AVIM). AVIM consists of two intercoupled components: physical processes, involving water and energy transfer among soil, vegetation and the atmosphere at the land surface and eco-physiological processes, i.e. photosynthesis, respiration, dry matter allocation, littering, phenology. Globally vegetation is classified into 13 types and soil texture is classified into 6 types. The estimated NPP for different vegetation types at 1637 sites are validated with the observed data provided by EMDI. The main results of NPP estimation show that global averaged NPP is 405.13 g C m(-2)yr(-1), varying from 99.58 g C m(-2)yr(-1) (tundra) to 996.2 g m(-2)yr(-1) (rainforest). Global total annual NPP is about 60.72Gt C yr(-1), in which the maximum part, about 15.84 Gt C yr(-1), accounting for 26.09% of the total is contributed by tropical rainforest. The maximum carbon sink occurs in the temperate region of the Northern Hemisphere. The global spatial and seasonal distribution of terrestrial NPP is estimated reasonably.
基金supported by the Knowledge Innovation Program of the Chinese Academy of Sciences (Grant No. IAP07114)"Interaction of Indian-Pacific Ocean and the significance of influence to the South China Sea circumfluence" (GrantNo. KZCX2-YW-214)the project of the National Natural Science Foundation of China (Grant Nos. 40605025,40675049, and 40730106)
文摘The coupled models of both the Global Ocean-Atmosphere-Land System （GOALS） and the Atmosphere- Vegetation Interaction Model （GOALS-AVIM） are used to study the main characteristics of interannual variations. The simulated results are also used to investigate some significant interannual variability and correlation analysis of the atmospheric circulation and terrestrial ecosystem. By comparing the simulations of the climate model GOALS-AVIM and GOALS, it is known that the simulated results of the interannual variations of the spatial and temporal distributions of the surface air temperatures and precipitation are generally improved by using AVIM in GOALS-AVIM. The interannual variation displays some distinct characteristics of the geographical distribution. Both the Net Primary Production （NPP） and the Leap Area Index （LAI） have quasi 1-2-year cycles. Meanwhile, precipitation and the surface temperatures have 2-4- year cycles. Conditions when the spectrum density values of GOALS are less than those of GOALS-AVIM, tell us that the model coupled with AVIM enhances the simulative capability for interannual variability and makes the annual cycle variability more apparent. Using Singular Value Decomposition （SVD） analysis, the relationship between the ecosystem and the atmospheric circulation in East Asia is explored. The result shows that the strengthening and weakening of the East Asian monsoon, characterized by the geopotential heights at 500 hPa and the wind fields at 850 hPa, correspond to the spatiotemporal pattern of the NPP. The correlation between NPP and the air temperature, precipitation and solar radiation are different in interannual variability because of the variation in vegetation types.
基金National Key Basic Research and Development Program granted by the Ministry of Science and Technology of China(MOST)with project number G1999043500the Innovation Program of the Chinese Academy of Sciences with project number ZKCX2-SW-210the National Natural Science Foundation of China(NSFC)under Grant No.49975016
文摘A two-way coupling simulation from the NCAR's regional climate model REGCM2 (called R-2 hereafter) and the SUCROS model for crop growth developed by the Wageningen Agricultural University,the Netherlands (both models,when in combination,denoted as R/S) are carried out on the interactions between crops and atmosphere in the Huang-Huai-Hai Plain in East China. Evidence suggests that the R/S simulations can depict pretty well the dynamic biology-based interactions between the factors,revealing reasonably both the day-to-day variations in leaf area index (LAI) and land surface physics therein,and particularly the improvement of the simulation, independently by use of the R-2,of summer precipitation and surface temperature in the research region.As a result,the present research is of significance to the further understanding of the interaction between the climate system and the terrestrial ecological systems.
