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1.
全球植被与大气之间碳通量的模式估计(英文)   总被引:1,自引:0,他引:1  
用大气植被相互作用模式(AVIM)模拟了全球陆地植被的净初级生产力(NPP)。AVIM由相互耦合的两部分组成:物理过程,包括陆地表面水分和能量在土壤、植被与大气之间的传输;以及生理生态过程,如:光合、呼吸、干物质分配、凋落和物候等。全球的植被分为13类,土壤按质地分为6类。用EMDI提供的全球1637个包括不同植被类型的NPP观测点数据对模型进行了检验。NPP模拟的结果表明:全球陆地植被的平均NPP为405.13gCm-2yr-1,不同植被类型的平均 NPP变化范围在99.58 g Cm-2yr-1(苔原)到996.2 g Cm-2yr-1(热带雨林)之间。全球年总NPP为60.72GtCyr-1,其中最大的部分为热带雨林,15.84GtCyr-1,占全球的26.09%。最大的碳汇是在北半球的温带。模式模拟的NPP在全球的空间和季节分布是合理的。  相似文献   

2.
全球植被与大气之间碳通量的模式估计   总被引:15,自引:0,他引:15  
用大气植被相互作用模式(AⅥM)模拟了全球陆地植被的净初级生产力(NPP)。AⅥM由相互耦合的两部分组成:物理过程,包括陆地表面水分和能量在土壤、植被与大气之间的传输;以及生理生态过程,如:光合、呼吸、干物质分配、凋落和物候等。全球的植被分为13类,土壤按质地分为6类。用EMDI提供的全球1637个包括不同植被类型的NPP观测点数据对模型进行了检验。NPP模拟的结果表明:全球陆地植被的平均NPP为405.13 g C m-2yr-1,不同植被类型的平均NPP变化范围在99.58 g C m-2yr-l(苔原)到996.2 g C m-2yr-l(热带雨林)之间。全球年总NPP为60.72 Gt C yr-l,其中最大的部分为热带雨林,15.84 Gt C yr-1,占全球的26.09%。最大的碳汇是在北半球的温带。模式模拟的NPP在全球的空间和季节分布是合理的。  相似文献   

3.
Earth System Models (ESMs) are fundamental tools for understanding climate-carbon feedback. An ESM version of the Flexible Global Ocean-Atmosphere-Land System model (FGOALS) was recently developed within the IPCC AR5 Coupled Model Intercomparison Project Phase 5 (CMIP5) modeling framework, and we describe the development of this model through the coupling of a dynamic global vegetation and terrestrial carbon model with FGOALS-s2. The performance of the coupled model is evaluated as follows. The simulated global total terrestrial gross primary production (GPP) is 124.4 PgC yr-I and net pri- mary production (NPP) is 50.9 PgC yr-1. The entire terrestrial carbon pools contain about 2009.9 PgC, comprising 628.2 PgC and 1381.6 PgC in vegetation and soil pools, respectively. Spatially, in the tropics, the seasonal cycle of NPP and net ecosystem production (NEP) exhibits a dipole mode across the equator due to migration of the monsoon rainbelt, while the seasonal cycle is not so significant in Leaf Area Index (LAI). In the subtropics, especially in the East Asian monsoon region, the seasonal cycle is obvious due to changes in temperature and precipitation from boreal winter to summer. Vegetation productivity in the northern mid-high latitudes is too low, possibly due to low soil moisture there. On the interannual timescale, the terrestrial ecosystem shows a strong response to ENSO. The model- simulated Nifio3.4 index and total terrestrial NEP are both characterized by a broad spectral peak in the range of 2-7 years. Further analysis indicates their correlation coefficient reaches -0.7 when NEP lags the Nifio3.4 index for about 1-2 months.  相似文献   

4.
随着人口的不断增加,资源、环境、人口与发展之间的矛盾日益突出,土地资源能否生产足够的食物供养未来人口的问题受到普遍关注。基于1997—2006年辽宁省10 km×10 km分辨率的气象资料,通过自然植被净第一性生产力模型和农业生产力模型计算了农田、草地和湿地的生产力及其动态。结果表明:近10 a来辽宁省年平均气温呈略下降趋势,年降水量呈增加趋势。1997—2006年辽宁省植被年平均总净第一性生产力为(农田、草地和湿地)3.63×107 t•yr-1,其中农田、草地和湿地分别为2.18×107 t•yr-1、0.99×107 t•yr-1和0.46×107 t•yr-1。应用人口承载力模型计算出在宽裕型、小康型和富裕型3种消费水平下1997—2006年辽宁省的年平均总人口承载力,分别为2226.9万人、2035.3万人和2015.1万人。  相似文献   

5.
Net primary production (NPP) of crop represents the capacity of sequestrating atmospheric CO2 in agro-ecosystem, and it plays an important role in terrestrial carbon cycling. By linking the Crop-C model with climate change scenario projected by a coupled GCM FGOALS via geographical information system (GIS) techniques, crop NPP in China was simulated from 2000 to 2050. The national averaged surface air temperature from FGOALS is projected to increase by 1.0℃ over this period and the corresponding atmospheric CO2 concentration is 535 ppm by 2050 under the IPCC A1B scenario. With a spatial resolution of 10 ×10 km^2, model simulation indicated that an annual average increase of 0.6 Tg C yr^-1 (Tg=10^12 g) would be possible under the A1B scenario. The NPP in the late 2040s would increase by 5% (30 Tg C) within the 98×10^6 hm^2 cropland area in contrast with that in the early 2000s. A further investigation suggested that changes in the NPP would not be evenly distributed in China. A higher increase would occur in a majority of regions located in eastern and northwestern China, while a slight reduction would appear in Hebei and Tianjin in northern China. The spatial characteristics of the crop NPP change are attributed primarily to the uneven distribution of temperature change.  相似文献   

6.
针对《巴黎协定》提出的温控目标,利用耦合模式比较计划第五阶段(CMIP5)模式在RCP2.6、RCP4.5和RCP8.5情景下的模拟结果,初步分析了全球升温情景下陆地生态系统净初级生产力(NPP)相对于参考时段(1986—2005年)的变化,重点分析了1.5℃和2℃升温时NPP相对于参考时段的变化量,并探讨了大气CO2浓度、气温、降水和辐射的变化及其对NPP变化的影响。CMIP5基于各典型浓度路径模拟的全球陆地生态系统NPP均呈增加趋势,且NPP增加量与升温幅度成正比。在相同的升温幅度下,基于各典型浓度路径模拟的各环境因子和NPP的变化量较为一致。陆地生态系统NPP总量增加主要由大气CO2浓度上升驱动,其他环境因子的影响相对较弱。中国东南部、非洲中部、美国东南部和亚马孙雨林西部地区NPP增加最明显。NPP变化量的空间格局主要由大气CO2浓度增加和升温控制,降水和辐射的影响相对较小。具体而言,大气CO2浓度上升对中低纬度的NPP变化贡献最大,对北方高纬度地区NPP变化贡献较小。温度上升有利于促进北方高纬度地区和青藏高原地区NPP,但对中低纬度地区的NPP有较强的抑制作用。鉴于既有典型浓度路径和地球系统模型的限制,本文对未来升温情景下陆地生态系统NPP的预估仍存在较大的不确定性,需要在未来的研究中进一步改进。  相似文献   

7.
This article reviews recent advances over the past 4 years in the study of the carbon-nitrogen cycling and their relationship to climate change in China. The net carbon sink in the Chinese terrestrial ecosystem was 0.19-0.26 Pg C yr-1 for the 1980s and 1990s. Both natural wetlands and the rice-paddy regions emitted 1.76 Tg and 6.62 Tg of CH 4 per year for the periods 1995-2004 and 2005-2009, respectively. China emitted~1.1 Tg N 2 O-N yr-1 to the atmosphere in 2004. Land soil contained~8.3 Pg N. The excess nitrogen stored in farmland of the Yangtze River basin reached 1.51 Tg N and 2.67 Tg N in 1980 and 1990, respectively. The outer Yangtze Estuary served as a moderate or significant sink of atmospheric CO 2 except in autumn. Phytoplankton could take up carbon at a rate of 6.4 ×10 11 kg yr-1 in the China Sea. The global ocean absorbed anthropogenic CO 2 at the rates of 1.64 and 1.73 Pg C yr-1 for two simulations in the 1990s. Land net ecosystem production in China would increase until the mid-21st century then would decrease gradually under future climate change scenarios. This research should be strengthened in the future, including collection of more observation data, measurement of the soil organic carbon (SOC) loss and sequestration, evaluation of changes in SOC in deep soil layers, and the impacts of grassland management, carbon-nitrogen coupled effects, and development and improvement of various component models and of the coupled carbon cycle-climate model.  相似文献   

8.
Using the regional terrestrial Net Primary Production (NPP) from different observations and models over China, we validated the NPP simulations and explored the relationship between NPP and climate variation at interannual and decadal scales in the Modified Sheffield Dynamic Global Vegetation Model (M-SDGVM) during 1981–2000. M-SDGVM shows agreement with the NPP data from 743 sites under the Global Primary Production Data Initiative (GPPDI). The spatial and the zonal averaged NPP of M-SDGVM agree well with ...  相似文献   

9.
东亚夏季风可显著影响中国季风区气候变化,但是季风区植被净初级生产力(NPP)对夏季风气候变化的响应机理尚不明确。利用大气—植被相互作用模型(AVIM2)模拟了中国季风区植被NPP,分析了其与夏季风指数的相关关系,探讨了其对夏季风变化的响应机理。研究发现,我国南、北方植被对夏季风强度变化的响应方式和机理并不相同。强夏季风年北方植被NPP增加,而南方植被NPP减少。东亚夏季风对中国华北平原植被生长季NPP的作用主要是通过影响该地降水量实现的;京、津、冀地区植被NPP受东亚夏季风带来的气温和降水量变化的叠加影响,因而成为北方对夏季风变化最敏感的区域。东亚夏季风对我国南方江苏、安徽、湖南、湖北、江西植被NPP的作用是通过影响太阳辐射实现的,强夏季风导致太阳辐射减弱,从而使各省植被NPP减少。南方沿海的浙江和福建,强季风年带来的弱太阳辐射和低温是该地植被NPP减少的原因。广东、台湾植被NPP则主要受强夏季风带来的低温影响。  相似文献   

10.
The CASA (Carnegie-Ames-Stanford) ecosystem model has been used to estimate monthly carbon fluxes in terrestrial ecosystems from 2000 to 2009, with global data inputs from NASA??s Terra Moderate Resolution Imaging Spectroradiometer (MODIS) vegetation cover mapping. Net primary production (NPP) flux for atmospheric carbon dioxide has varied slightly from year-to-year, but was predicted to have increased over short multi-year periods in the regions of the high-latitude Northern Hemisphere, South Asia, Central Africa, and the western Amazon since the year 2000. These CASA results for global NPP were found to be in contrast to other recently published modeling trends for terrestrial NPP with high sensitivity to regional drying patterns. Nonetheless, periodic declines in regional NPP were predicted by CASA for the southern and western Untied States, the southern Amazon, and southern and eastern Africa. NPP in tropical forest zones was examined in greater detail to discover lower annual production values than previously reported in many global models across the tropical rainforest zones, likely due to the enhanced detection of lower production ecosystems replacing primary rainforest.  相似文献   

11.
东亚季风区夏季陆地生态系统碳循环对东亚夏季风的响应   总被引:3,自引:1,他引:2  
东亚地区陆地生态系统的时空变率表现出明显的对季风气候的响应特征。使用EOF(经验正交分解)方法分析了AVIM2动态植被陆面模式离线模拟试验模拟的1953~2004年东亚季风区夏季陆地生态系统总初级生产力(GPP)、生态系统净初级生产力(NPP)、净生态系统初级生产力(NEP)、植被呼吸以及土壤呼吸的时空分布特点,探讨了东亚夏季风对陆地生态系统碳循环影响机制。研究发现,在强季风年,江淮地区高温少雨的特点限制了光合作用,造成GPP偏低;而华南地区在强季风年气候温暖湿润,利于植被生长,GPP偏高。季风对于植被呼吸和土壤呼吸影响不明显,使得GPP和植被呼吸之差NPP的变化及NPP和土壤呼吸之差NEP的变化与GPP的变化保持一致。在强季风年江淮流域地区干热的气候条件使得NPP和NEP降低;但是在华南地区温度升高的同时降水增多使得在NPP偏高的基础上NEP也偏高。  相似文献   

12.
Paleoclimate simulations of the mid-Holocene (MH) and Last Glacial maximum (LGM) by the latest versions of the Flexible Global Ocean-Atmosphere-Land System model, Spectral Version 2 and Grid-point Version 2 (FGOALS-s2 and g2) are evaluated in this study. The MH is characterized by changes of insolation induced by orbital parameters, and the LGM is a glacial period with large changes in greenhouse gases, sea level and ice sheets. For the MH, both versions of FGOALS simulate reasonable responses to the changes of insolation, such as the enhanced summer monsoon in African-Asian regions. Model differences can be identified at regional and seasonal scales. The global annual mean surface air temperature (TAS) shows no significant change in FGOALS-s2, while FGOALS-g2 shows a global cooling of about 0.7 C that is related with a strong cooling during boreal winter. The amplitude of ENSO is weaker in FGOALS-g2, which agrees with proxy data. For the LGM, FGOALS-g2 captures the features of the cold and dry glacial climate, including a global cooling of 4.6 C and a decrease in precipitation by 10%. The ENSO is weaker at the LGM, with a tendency of stronger ENSO cold events. Sensitivity analysis shows that the Equilibrium Climate Sensitivity (ECS) estimated for FGOALS ranges between 4.23 C and 4.59 C. The sensitivity of precipitation to the changes of TAS is~2.3% C-1 , which agrees with previous studies. FGOALS-g2 shows better simulations of the Atlantic Meridional Overturning Circulation (AMOC) and African summer monsoon precipitation in the MH when compared with FGOALS-g1.0; however, it is hard to conclude any improvements for the LGM.  相似文献   

13.
Climate model simulations available from the PMIP1, PMIP2 and CMIP (IPCC-AR4) intercomparison projects for past and future climate change simulations are examined in terms of polar temperature changes in comparison to global temperature changes and with respect to pre-industrial reference simulations. For the mid-Holocene (MH, 6,000 years ago), the models are forced by changes in the Earth’s orbital parameters. The MH PMIP1 atmosphere-only simulations conducted with sea surface temperatures fixed to modern conditions show no MH consistent response for the poles, whereas the new PMIP2 coupled atmosphere–ocean climate models systematically simulate a significant MH warming both for Greenland (but smaller than ice-core based estimates) and Antarctica (consistent with the range of ice-core based range). In both PMIP1 and PMIP2, the MH annual mean changes in global temperature are negligible, consistent with the MH orbital forcing. The simulated last glacial maximum (LGM, 21,000 years ago) to pre-industrial change in global mean temperature ranges between 3 and 7°C in PMIP1 and PMIP2 model runs, similar to the range of temperature change expected from a quadrupling of atmospheric CO2 concentrations in the CMIP simulations. Both LGM and future climate simulations are associated with a polar amplification of climate change. The range of glacial polar amplification in Greenland is strongly dependent on the ice sheet elevation changes prescribed to the climate models. All PMIP2 simulations systematically underestimate the reconstructed glacial–interglacial Greenland temperature change, while some of the simulations do capture the reconstructed glacial–interglacial Antarctic temperature change. Uncertainties in the prescribed central ice cap elevation cannot account for the temperature change underestimation by climate models. The variety of climate model sensitivities enables the exploration of the relative changes in polar temperature with respect to changes in global temperatures. Simulated changes of polar temperatures are strongly related to changes in simulated global temperatures for both future and LGM climates, confirming that ice-core-based reconstructions provide quantitative insights on global climate changes. An erratum to this article can be found at  相似文献   

14.
陆地生态系统碳汇显著降低大气CO2浓度上升和全球变暖的速率,受人类活动和气候变化的影响,陆地生态系统碳通量具有强烈的时空变化,其估算结果仍存在较大的不确定性,不同因子的贡献尚不清晰。为此,利用遥感驱动的陆地生态系统过程模型BEPS模拟分析了1981—2019年全球陆地生态系统碳通量的时空变化特征,评价了大气CO2浓度、叶面积指数(Leaf Area Index,LAI)、氮沉降、气候变化对全球陆地生态系统碳收支变化的贡献。1981—2019年全球陆地生态系统总初级生产力(Gross Primary Productivity,GPP)、净初级生产力(Net Primary Productivity,NPP)和净生态系统生产力(Net Ecosystem Productivity,NEP)的平均值分别为115.3、51.3和2.7 Pg·a-1(以碳质量计,下同),上升速率分别为0.47、0.21和0.06 Pg·a-1。全球大部分区域GPP和NPP显著增加,NEP显著上升(p<0.05)的区域明显少于GPP和NPP。1981—2019年,全球NEP累积为105.2 Pg,森林、稀树草原及灌木、农田和草地的贡献分别为76.4、15.8、9.4和3.6 Pg。CO2浓度、LAI、氮沉降和气候变化各自对NEP的累积贡献分别为58.4、20.6、0.7和-43.6 Pg,全部4个因子变化对NEP的累积贡献为39.8 Pg,其中CO2浓度上升是近40 a全球陆地生态系统NEP上升的主要贡献因子,其次为LAI。  相似文献   

15.
A comparative study was carried out to explore carbon monoxide total columnar amount(CO TC) in background and polluted atmosphere, including the stations of ZSS(Zvenigorod), ZOTTO(Central Siberia), Peterhof, Beijing, and Moscow,during 1998–2014, on the basis of ground-and satellite-based spectroscopic measurements. Interannual variations of CO TC in different regions of Eurasia were obtained from ground-based spectroscopic observations, combined with satellite data from the sensors MOPITT(2001–14), AIRS(2003–14), and IASI Met Op-A(2010–13). A decreasing trend in CO TC(1998–2014) was found at the urban site of Beijing, where CO TC decreased by 1.14% ± 0.87% yr~(-1). Meanwhile, at the Moscow site, CO TC decreased remarkably by 3.73% ± 0.39% yr~(-1). In the background regions(ZSS, ZOTTO, Peterhof), the reduction was 0.9%–1.7% yr~(-1) during the same period. Based on the AIRSv6 satellite data for the period 2003–14, a slight decrease(0.4%–0.6% yr~(-1)) of CO TC was detected over the midlatitudes of Eurasia, while a reduction of 0.9%–1.2% yr~(-1) was found in Southeast Asia. The degree of correlation between the CO TC derived from satellite products(MOPITTv6 Joint, AIRSv6 and IASI Met Op-A) and ground-based measurements was calculated, revealing significant correlation in unpolluted regions.While in polluted areas, IASI Met Op-A and AIRSv6 data underestimated CO TC by a factor of 1.5–2.8. On average, the correlation coefficient between ground-and satellite-based data increased significantly for cases with PBL heights greater than 500 m.  相似文献   

16.
Monitoring atmospheric carbon dioxide(CO_2) from space-borne state-of-the-art hyperspectral instruments can provide a high precision global dataset to improve carbon flux estimation and reduce the uncertainty of climate projection. Here, we introduce a carbon flux inversion system for estimating carbon flux with satellite measurements under the support of "The Strategic Priority Research Program of the Chinese Academy of Sciences—Climate Change: Carbon Budget and Relevant Issues". The carbon flux inversion system is composed of two separate parts: the Institute of Atmospheric Physics Carbon Dioxide Retrieval Algorithm for Satellite Remote Sensing(IAPCAS), and Carbon Tracker-China(CT-China), developed at the Chinese Academy of Sciences. The Greenhouse gases Observing SATellite(GOSAT) measurements are used in the carbon flux inversion experiment. To improve the quality of the IAPCAS-GOSAT retrieval, we have developed a post-screening and bias correction method, resulting in 25%–30% of the data remaining after quality control. Based on these data, the seasonal variation of XCO_2(column-averaged CO_2dry-air mole fraction) is studied, and a strong relation with vegetation cover and population is identified. Then, the IAPCAS-GOSAT XCO_2 product is used in carbon flux estimation by CT-China. The net ecosystem CO_2 exchange is-0.34 Pg C yr~(-1)(±0.08 Pg C yr~(-1)), with a large error reduction of 84%, which is a significant improvement on the error reduction when compared with in situ-only inversion.  相似文献   

17.
Soil respiration is a key component of the global terrestrial ecosystem carbon cycle. The static opaque chamber method was used to measure the CO2 effluxes from soil of a semiarid Aneurolepidium chinense steppe and a Stipa krylovii steppe in the Xilin River Basin of Inner Mongolia, China from March 2002 to December 2004. The results indicated that the soil respiration rates of the semiarid Aneurolepidium chinense steppe and the Stipa krylovii steppe were both relatively high from mid-May to mid-September of each year and remained low during the rest of the year. The minimum value of soil respiration occurred in December or January and negative effluxes of CO2 appeared for several days during the non-growing season of individual years at the two sampling sites. A high annual variation was found in the two steppes with the coefficients of variance (CV) being over 94%, even high to 131%. The annual sums of soil CO2 efflux of the Aneurolepidium chinense steppe varied between 356.4 gC m?2 yr?1 and 408.8 gC m?2 yr?1, while those of the Stipa krylovii steppe in the three years were in the range of 110.6 gC m?2 yr?1 to 148.6 gC m?2 yr?1. The mean respiration rates of the Aneurolepidium chinense steppe were significantly higher than those of the Stipa krylovii steppe in different statistical periods with the exception of the non-growing season. About 59.9% and 80.6% of the soil respiration variations in both steppes for the whole sampling period were caused by the changes of temperature and soil water content. In the Aneurolepidium chinense steppe, the soil respiration rate has significant or extremely significant positive correlation (r = 0.58 ? 0.85, p < 0.05 or p < 0.01) with air temperature and ground temperature of the topsoil except in 2002; the unique contributions of temperature change to the soil respiration variation of the three years were 53.3%, 81.0% and 58.6%, respectively. But, for the Stipa krylovii steppe in the same time interval, the soil water content (especially that of the 10–20 cm layer) has a greater effect on the change of soil respiration, and the unique contributions of the change of the 10–20 cm soil water content to the variations of soil respiration in 2002 and 2003 were 60.0% and 54.3%, respectively. In 2004, in spite of the higher contribution of temperature than soil water content, the contribution of ground temperature at a depth of 10 cm was only 46.2%, much weaker than that of any single year in the Aneurolepidium chinense steppe.  相似文献   

18.
By using a 9-level global atmospheric general circulation model developed at the Institute of Atmospheric Physics (IAP9L-AGCM) under the Chinese Academy of Sciences, the authors investigated the response of the East Asian monsoon climate to changes both in orbital forcing and the snow and glaciers over the Tibetan Plateau at the mid-Holocene, about 6000 calendar years before the present (6 kyr BP). With the Earth’s orbital parameters appropriate for the mid-Holocene, the IAP9L-AGCM computed warmer and wetter conditions in boreal summer than for the present day. Under the precondition of continental snow and glacier cover existing over part of the Tibetan Plateau at the mid-Holocene, the authors examined the regional climate response to the Tibetan Plateau cooling. The simulations indicated that climate changes in South Asia and parts of central Asia as well as in East Asia are sensitive to the Tibetan Plateau cooling at the mid-Holocene, showing a significant decrease in precipitation in northern India, northern China and southern Mongolia and an increase in Southeast Asia during boreal summer. The latter seems to correspond to the weakening, southeastward shift of the Asian summer monsoon system resulting from reduced heat contrast between the Eurasian continent and the Pacific and Indian Oceans when a cooling over the Tibetan Plateau was imposed. The simulation results suggest that the snow and glacier environment over the Tibetan Plateau is an important factor for mid-Holocene climate change in the areas highly influenced by the Asian monsoon.  相似文献   

19.
We use a georeferenced model of ecosystem carbon dynamics to explore the sensitivity of global terrestrial carbon storage to changes in atmospheric CO2 and climate. We model changes in ecosystem carbon density, but we do not model shifts in vegetation type. A model of annual NPP is coupled with a model of carbon allocation in vegetation and a model of decomposition and soil carbon dynamics. NPP is a function of climate and atmospheric CO2 concentration. The CO2 response is derived from a biochemical model of photosynthesis. With no change in climate, a doubling of atmospheric CO2 from 280 ppm to 560 ppm enhances equilibrium global NPP by 16.9%; equilibrium global terrestrial ecosystem carbon (TEC) increases by 14.9%. Simulations with no change in atmospheric CO2 concentration but changes in climate from five atmospheric general circulation models yield increases in global NPP of 10.0–14.8%. The changes in NPP are very nearly balanced by changes in decomposition, and the resulting changes in TEC range from an increase of 1.1% to a decrease of 1.1%. These results are similar to those from analyses using bioclimatic biome models that simulate shifts in ecosystem distribution but do not model changes in carbon density within vegetation types. With changes in both climate and a doubling of atmospheric CO2, our model generates increases in NPP of 30.2–36.5%. The increases in NPP and litter inputs to the soil more than compensate for any climate stimulation of decomposition and lead to increases in global TEC of 15.4–18.2%.  相似文献   

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