1981-2008年中国陆地植被NPP对气候变化响应的敏感性试验

在验证CENTURY模型对中国陆地植被净初级生产力(Net Primary Productivity,NPP)模拟能力的基础上,利用该模型探讨了1981-2008年中国陆地植被NPP的年际变异和变化趋势对CO₂浓度、温度和降水变化的响应。结果表明,中国陆地植被NPP对不同气候因子的响应程度存在明显不同。其中,CO₂浓度变化对植被NPP年际变异的影响不显著,但能够引起中国大部分地区植被NPP趋势系数增大;温度对中国中高纬度地区植被NPP的年际变化影响显著,但就全国范围而言,植被NPP年际变异对温度变化的响应程度总体低于对降水变化的响应程度;降水变化是对中国植被NPP变化趋势起主导作用的气候因子。此外,综合考虑温度和降水变化的影响发现,植被NPP变化趋势的响应特征类似于降水单独变化时植被NPP变化趋势的响应特征。     

CMIP6模式对亚洲陆地生态系统的模拟评估与预估

基于国际耦合模式比较计划第六阶段（CMIP6）模式模拟以及观测数据,评估了9个CMIP6模式对亚洲地区叶面积指数（LAI)、总初级生产力（GPP）和净初级生产力（NPP）的模拟性能。模拟评估结果表明,9个CMIP6模式能够较好地模拟出亚洲地区陆地生态系统LAI、GPP和NPP的时空分布特征。综合来看,多模式集合（MME）模拟效果最佳,其模拟的LAI、GPP和NPP与观测的空间相关系数分别达到0.90、0.81和0.89,均方根误差在0.5左右。在此基础上,利用MME结果进一步预估了亚洲地区陆地生态系统在SSP1-2.6、SSP2-4.5和SSP5-8.5情景下的未来变化。总体而言,亚洲地区LAI、GPP和NPP到21世纪末都呈现上升趋势。其中,温室气体高排放情景下的上升趋势大于温室气体低排放情景下的上升趋势,亚洲中高纬度地区的增幅大于低纬度地区的增幅。从区域平均来看,到21世纪末期,与当今气候态相比,北亚LAI、GPP和NPP的增幅最大,其在SSP5-8.5情景下分别增加68%、106%和90%;东南亚增幅最小,分别为15%、34%和39%。在SSP1-2.6情景下,北亚LAI、GPP和NPP在21世纪末的增幅分别为23%、29%和26%;东南亚分别为3%、10%和11%,意味着未来全球变暖背景下亚洲区域陆地生态系统变绿和固碳幅度加强。     

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

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。     

典型温带针阔叶混交林碳收支对温度的响应特征

森林生态系统是一个庞大的碳储备系统,在当前气候变暖条件下,温度变化会对森林生态系统的碳收支过程产生重要影响。该文选择长白山温带针阔混交林森林生态系统（CBS）作为研究对象,利用多年通量及小气候观测资料分析该生态系统碳收支过程对温度的响应特征,结果显示该温带森林碳交换的季节变化特征十分明显。生态系统总初级生产力GPP、生态系统呼吸R_e和净生态系统碳交换NEE在2003—2008年的月平均变化显示,碳收支3个组分最大值均出现在夏季,GPP最大值出现在7月,R_e最大值主要出现在8月,NEE负方向的最大值主要出现在6月或7月,表现为碳吸收。在日尺度和月尺度对温度的响应上,GPP和R_e都是随温度（气温和5 cm土壤温度）呈显著的指数升高形式。在日尺度上和月尺度上, NEE对气温的响应皆是分段线性形式,先是随气温的上升而正向增大,表现为碳排放;当超过临界温度,随气温的继续上升而负值增大,表现为碳吸收。根据温度、GPP、R_e以及NEE的季节的变化,每年达到最大的GPP、R_e以及NEE的最适温度均不同,这表明了在气温变化的背景下,生态系统的最适温度也在随之改变,也表明了不考虑其它因素的影响,在气候变暖的背景下,长白山针阔混交林森林生态系统的GPP、R_e随气温的升高增大,而NEE随气温的升高而减小。     

近地层臭氧对我国树木生产力和作物产量的影响:进展与展望

大气污染严重威胁了我国陆地生态系统的固碳能力,但随着减污降碳协同治理的快速推进,减缓大气污染将有利于提升陆地碳汇,并切实推动碳达峰碳中和目标的实现。为了更好地理解大气污染与生态系统固碳的关系,本文以主要空气污染物臭氧（O₃）为例,基于田间控制实验的整合分析、剂量响应关系及机理模型三种评估方法综述了近地层O₃污染对植被碳固定影响的最新进展。尽管不同作物种类以及品种、不同功能型木本植物对O₃的响应有着显著的差异,且各种方法的评估结果也不尽相同,但目前O₃浓度造成我国粮食作物减产、森林生产力降低已是不争的事实。持续升高的O₃浓度将严重威胁我国陆地生态系统的固碳能力。利用我国作物和树木的O₃剂量响应方程进行评估的结果表明,在CO₂减排和O₃污染协同治理下,预计2060年我国树木生物量和作物产量将比当前显著提高,增加陆地生态系统碳汇,助力碳中和目标。最后,对如何提高O₃污染环境下植物固碳能力也进行了展望。     

陆地生态系统固碳速率立体监测方法:进展与挑战

全球CO₂浓度增加造成的全球变暖已成为人类亟需解决的问题,陆地生态系统在过去几十年一直扮演着重要的碳汇角色,吸收了30％左右的人类活动排放CO₂。本文调研分析了陆地生态系统固碳速率空间估算方法,包括样地调查、通量监测、模型模拟、遥感估算等,梳理了各种估算方法的研究现状与进展。样地调查、通量观测等方法可以提供点尺度的固碳速率直接测量信息,但存在观测样本有限、空间代表性不足等问题。模型模拟方法可以从机理的角度描述陆地碳、水、能量循环,模拟预测陆地生态系统固碳速率的状态和变化。然而,在模型建立过程中,抽象和简化会引入结构与假设的不确定性,以及模型驱动数据引入的不确定性等问题是碳循环模型模拟方法面临的重大挑战。卫星遥感具有全球覆盖、分辨率精细、时间序列观测等优点,结合机器学习方法,为地球大数据驱动的全球碳源汇估算提供了新的研究范式。但是,当前各种固碳速率的监测方法还没有满足高度时空异质性的陆地生态系统固碳量监测需求,未来需要整合地面观测、模型模拟和卫星遥感等多种技术手段,提供区域和全球尺度的陆地生态系统碳汇精确估算方法体系和科学数据产品。     

山西省城市大气CO2本底筛分对比及特征分析

基于典型城市站太原站2018年3月—2019年2月的大气CO₂在线观测资料，利用筛分法（Meteorological filtering method，MET）和黑碳示踪法（Black Carbon tracer，BC）进行本底/非本底的筛分，得到了本底浓度的变化特征。结果表明，太原大气CO₂浓度季均值冬季最高，夏季最低；不同季节呈"单峰型"日变化特征，日振幅均在26.0×10^-6以上；4个季节CO₂浓度与地面风速存在显著负相关关系；CO₂浓度抬升区域主要受当地工业布局的影响，最大抬升幅度在秋季达17.4×10^-6；使用气象筛分法（MET）得到年均本底浓度为（431.4±19.9）×10^-6，人为排放等对其影响为23.5×10^-6，年振幅比同纬度其它本底站大，为34.5×10^-6；黑碳示踪法（BC）得到冬季季均本底浓度为（445.0±22.9）×10^-6，比MET筛分法得到的季均值高0.8×10^-6，两种筛分法得到的CO₂浓度变化趋势一致。     

全球FLUXNET站点总初级生产力的年际变化及其主导因子解析

基于耶鲁互动生物圈模式（YIBs）,结合FLUXNET网络观测时间超过8 a的站点的观测数据,研究对不同气象因子影响下总初级生产力（Gross Primary Productivity,GPP）的年际变化进行分析,探讨各植被类型GPP年际变化的主要驱动因子。结果表明,光合有效辐射的变化是落叶阔叶林和常绿针叶林站点GPP年际变化的主要驱动因子,贡献了这些森林类型年际变率的80%。相对湿度变化是作物站点GPP年际变化的主要驱动因子,贡献了作物GPP年际变率的65%。温度是灌木丛站点GPP年际变率的重要因子,其贡献率达到58%。草原站点GPP年际变化的不确定性较大,没有统一的主导因子。研究结果表明,气象要素是全球陆地GPP年际变化的主导因素。在未来气候变化背景下,极端气候事件频发可能会进一步增加GPP的年际变率。     

锡林浩特草原CO2通量特征及其影响因素分析

利用锡林浩特国家气候观象台开路涡度相关系统、辐射土壤观测系统,测得的长期连续通量观测数据,对锡林浩特草原2009—2011年期间的CO₂通量观测特征进行了分析。结果表明:CO₂通量存在明显的年际、季节和日变化特征。3 a中NEE年际变率达到200 g·m^-2,季节变率最大达到460 g·m^-2,日变化幅度生长季最大达到0.25 mg·m^-2·s^-1。通过不同时间尺度碳通量与温度、水分、辐射等环境因子的分析,认为CO₂通量日变化主要受温度和光合有效辐射影响,而季节变化和年变化主要受降水和土壤含水量的影响。降水强度及时间分布是制约牧草CO₂吸收的关键因素,大于15%的土壤含水量有利于促进牧草生长。     

基于WRF模式的京津冀地区地表大气CO2浓度的模拟研究

在“双碳”目标背景下，从国家层面到地方层面，区域、城市、行业企业都在制定和实施双碳目标行动计划。CO₂模拟因其客观性和高时空分辨率等优势，在城市碳排放研究中深受重视。本研究以京津冀地区为研究区域，采用Picarro仪器高精度观测的2019—2020年CO₂数据，利用WRF模式进行CO₂传输模拟，分析了CO₂浓度变化的季节特征，评估了模式在城区中心、城郊及背景3个观测站点的模拟效果，并对边界层高度及化石燃料碳排放等可能影响CO₂浓度的因素进行了研究。3个观测站点分别为北京中国科学院大气物理研究所325 m气象塔观测站（北京站）、河北香河观测站（香河站）和上甸子区域本底观测站（上甸子站）。模拟结果表明：上甸子站优于香河站，香河站优于北京站，在冬季尤其明显；CO₂浓度的高值区主要分布在城区、电厂和工业区，尤其是唐山、石家庄和邯郸地区，大量交通、工业排放导致CO₂浓度明显上升，且高值区的范围在冬季最大；就日平均变化和日变化而言，边界层高度与CO₂浓度存在相反变化趋势；3个站点的化石燃料碳排放（FFECO2）与近地面总CO₂浓度存在正相关关系，冬春季的相关性高于夏秋季，且FFECO2的占比从大到小依次为北京站、香河站、上甸子站；CO₂传输模拟的不确定性存在空间差异和季节变化。     

Detecting a Terrestrial Biosphere Sink for Carbon Dioxide: Interannual Ecosystem Modeling for the Mid-1980s

There is considerable uncertainty as to whether interannual variability in climate and terrestrial ecosystem production is sufficient to explain observed variation in atmospheric carbon content over the past 20–30 years. In this paper, we investigated the response of net CO₂ exchange in terrestrial ecosystems to interannual climate variability (1983 to 1988) using global satellite observations as drivers for the NASA-CASA (Carnegie-Ames-Stanford Approach) simulation model. This computer model of net ecosystem production (NEP) is calibrated for interannual simulations driven by monthly satellite vegetation index data (NDVI) from the NOAA Advanced Very High Resolution Radiometer (AVHRR) at 1 degree spatial resolution. Major results from NASA-CASA simulations suggest that from 1985 to 1988, the northern middle-latitude zone (between 30 and 60°N) was the principal region driving progressive annual increases in global net primary production (NPP; i.e., the terrestrial biosphere sink for carbon). The average annual increase in NPP over this predominantly northern forest zone was on the order of +0.4 Pg (10¹⁵ g) C per year. This increase resulted mainly from notable expansion of the growing season for plant carbon fixation toward the zonal latitude extremes, a pattern uniquely demonstrated in our regional visualization results. A net biosphere source flux of CO₂ in 1983–1984, coinciding with an El Niño event, was followed by a major recovery of global NEP in 1985 which lasted through 1987 as a net carbon sink of between 0.4 and 2.6 Pg C per year. Analysis of model controls on NPP and soil heterotrophic CO₂ fluxes (R_h) suggests that regional warming in northern forests can enhance ecosystem production significantly. In seasonally dry tropical zones, periodic drought and temperature drying effects may carry over with at least a two-year lag time to adversely impact ecosystem production. These yearly patterns in our model-predicted NEP are consistent in magnitude with the estimated exchange of CO₂ by the terrestrial biosphere with the atmosphere, as determined by previous isotopic (¹³C) deconvolution analysis. Ecosystem simulation results can help further target locations where net carbon sink fluxes have occurred in the past or may be verified in subsequent field studies.     

The Potential Response of Terrestrial Carbon Storage to Changes in Climate and Atmospheric CO2

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%.     

Earth System Model FGOALS-s2: Coupling a dynamic global vegetation and terrestrial carbon model with the physical climate system model

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.     

Climate and Vegetation Drivers of Terrestrial Carbon Fluxes:A Global Data Synthesis

The terrestrial carbon(C) cycle plays an important role in global climate change, but the vegetation and environmental drivers of C fluxes are poorly understood. We established a global dataset with 1194 available data across site-years including gross primary productivity(GPP), ecosystem respiration(ER), net ecosystem productivity(NEP), and relevant environmental factors to investigate the variability in GPP, ER and NEP, as well as their covariability with climate and vegetation drivers.The results indicated that both GPP and ER increased exponentially with the increase in mean annual temperature(MAT)for all biomes. Besides MAT, annual precipitation(AP) had a strong correlation with GPP(or ER) for non-wetland biomes.Maximum leaf area index(LAI) was an important factor determining C fluxes for all biomes. The variations in both GPP and ER were also associated with variations in vegetation characteristics. The model including MAT, AP and LAI explained 53%of the annual GPP variations and 48% of the annual ER variations across all biomes. The model based on MAT and LAI explained 91% of the annual GPP variations and 92.9% of the annual ER variations for the wetland sites. The effects of LAI on GPP, ER or NEP highlighted that canopy-level measurement is critical for accurately estimating ecosystem–atmosphere exchange of carbon dioxide. The present study suggests a significance of the combined effects of climate and vegetation(e.g.,LAI) drivers on C fluxes and shows that climate and LAI might influence C flux components differently in different climate regions.     

Seasonal variation and meteorological control of CO2 flux in a hilly plantation in the mountain areas of North China

The carbon cycle of terrestrial ecosystems is an important scientific issue in global climate change research.Plantation forest plays an important role in terrestrial carbon budget in China.In this study,eddy covariance flux data measured at Xiaolangdi forest ecosystem research station(XLD) in 2007 and 2008 are used to analyze the seasonal variation and meteorological control of CO2 flux in a 30-yr-old mixed plantation.The plantation forest mainly consists of Quercus variabilis,Platycladus orientalis,and Robinia pseudoacacia.The results show that the seasonal variations of net ecosystem exchange of CO2(NEE),gross primary production(GPP),and ecosystem respiration(Re) display single-peak curves.The maximum of carbon sequestration appears during May and June each year.The relative contribution of carbon release from ecosystem respiration to GPP varied slightly between 2007 and 2008.The relationship between NEE and photosynthetic active radiation(Qp) accords with the rectangular hyperbola model on diurnal scale,and shows a good linear correlation on monthly scale.The ecosystem photosynthetic parameters:the maximum photosynthetic rate(Pmax),the ecosystem photosynthetic photonyield(α),and the daytime ecosystem respiration(Rd) exhibit seasonal variations.Pmax reaches the maximum in August each year,with small interannual difference.The interannual differences of α and Rd are obvious,which is attributed to the changes of meteorological factors,such as solar radiation,vapor pressure deficit(D),precipitation,etc.Parameters Re,GPP,and NEP(net ecosystem production) have obvious exponential relations with temperature on monthly scale.There is a hysteresis in the response of GPP and NEP to temperature,i.e.,the carbon sequestration is not the maximum when the temperature reaches the peak value.The Q10 values were 1.37 and 1.45 in 2007 and 2008,respectively.On monthly scale,Re,GPP,and NEE increase as D increases,but rise slowly and even decrease when D is higher than 1.5 kPa.     

Trends in carbon sink along the Belt and Road in the future under high emission scenario

Over the past three decades, the drawdown of atmospheric CO₂ in vegetation and soil has fueled net ecosystem production (NEP). Here, a global land-surface model (CABLE) is used to estimate the trend in NEP and its response to atmospheric CO₂, climate change, biological nitrogen (N) fixation, and N deposition under future conditions from 2031 to 2100 in the Belt and Road region. The trend of NEP simulated by CABLE decreases from 0.015 Pg carbon (C) yr^?2 under present conditions (1936–2005) to ?0.023 Pg C yr^?2 under future conditions. In contrast, the trend in NEP of the CMIP6 ensemble changes from 0.014 Pg C yr^?2 under present conditions to ?0.009 Pg C yr^?2 under future conditions. This suggests that the trend in the C sink for the Belt and Road region will likely decline in the future. The significant difference in the NEP trend between present and future conditions is mainly caused by the difference in the impact of climate change on NEP. Considering the responses of soil respiration (RH) or net primary production (NPP) to surface air temperature, the trend in surface air temperature changes from0.01°C yr^?1 under present conditions to 0.05°C yr^?1 under future conditions. CABLE simulates a greater response of RH to surface temperature than that of NPP under future conditions, which causes a decreasing trend in NEP. In addition, the greater decreasing trend in NEP under future conditions indicates that the C–climate–N interaction at the regional scale should be considered. It is important to estimate the direction and magnitude of C sinks under the C neutrality target.摘要目前, 在区域尺度, NEP趋势变化的强度和影响机制还存在很大的不确定性. 针对这一问题, 我们选取了一带一路覆盖的区域为研究对象, 基于全球陆面模式 (CABLE)和第六次国际耦合模式比较计划 (CMIP6), 评估了历史和未来NEP趋势的变化, 分析了影响的机制. 从过去到未来, CABLE结果表明NEP的趋势从 0.015 Pg C yr^?2 减少到 –0.023 Pg C yr^?2; CMIP6结果为从0.014 Pg C yr^?2转变为–0.009 Pg C yr^?2. 气候变化是引起这一变化的主因. 我们的研究结果强调了碳-气候-氮相互作用的重要性, 这对碳中和目标下碳汇潜力的准确估算尤为重要.     

Climate-related uncertainties in projections of the twenty-first century terrestrial carbon budget: off-line model experiments using IPCC greenhouse-gas scenarios and AOGCM climate projections

A terrestrial ecosystem model (Sim-CYCLE) was driven by multiple climate projections to investigate uncertainties in predicting the interactions between global environmental change and the terrestrial carbon cycle. Sim-CYCLE has a spatial resolution of 0.5°, and mechanistically evaluates photosynthetic and respiratory CO₂ exchange. Six scenarios for atmospheric-CO₂ concentrations in the twenty-first century, proposed by the Intergovernmental Panel on Climate Change, were considered. For each scenario, climate projections by a coupled atmosphere–ocean general circulation model (AOGCM) were used to assess the uncertainty due to socio-economic predictions. Under a single CO₂ scenario, climate projections with seven AOGCMs were used to investigate the uncertainty stemming from uncertainty in the climate simulations. Increases in global photosynthesis and carbon storage differed considerably among scenarios, ranging from 23 to 37% and from 24 to 81 Pg C, respectively. Among the AOGCM projections, increases ranged from 26 to 33% and from 48 to 289 Pg C, respectively. There were regional heterogeneities in both climatic change and carbon budget response, and different carbon-cycle components often responded differently to a given environmental change. Photosynthetic CO₂ fixation was more sensitive to atmospheric CO₂, whereas soil carbon storage was more sensitive to temperature. Consequently, uncertainties in the CO₂ scenarios and climatic projections may create additional uncertainties in projecting atmospheric-CO₂ concentrations and climates through the interactive feedbacks between the atmosphere and the terrestrial ecosystem.     

Changes in the seasonal amplitude of northern ecosystem productivity under future global warming

Observations have shown a largely enhanced seasonal amplitude of northern atmospheric CO₂ in the past several decades, and this enhancement is attributable to the increased seasonal amplitude of northern net ecosystem productivity (NEP amplitude). In the future, however, the changes in NEP amplitude are not clear, because of the uncertainties in climate change and vegetation dynamics. This study investigated the changes in NEP amplitude north of 45°N under future global warming by using a dynamic global vegetation model (DGVM). The authors conducted two sets of simulations: a present-day simulation (1981–2000) and future simulations (2081–2100) forced by RCP8.5 outputs from CMIP5. The results showed an overall enhanced northern NEP amplitude under the RCP8.5 scenario because of the increased maximum NEP and the decreased minimum NEP. The increases (decreases) in the maximum (minimum) NEP resulted from stronger (weaker) positive changes in gross primary production (GPP) than ecosystem respiration (ER). Changes in GPP and ER are both dominantly driven by surface air temperature and vegetation dynamics. This work highlights the key role of vegetation dynamics in regulating the northern terrestrial carbon cycle and the importance of including a DGVM in Earth system models.摘要观测显示过去几十年北半球大气二氧化碳季节幅度大幅增加, 这主要是由北半球陆地净生态系统生产力季节幅度的增加所致. 但是, 因为气候变化和植被动态的不确定性, 未来陆地净生态系统生产力季节幅度的变化还很不清楚. 本工作利用全球植被动力学模式研究了全球变暖背景下北纬45°以北陆地净生态系统生产力季节幅度的变化. 作者做了两大类试验: 当代试验 (1981−2000) 和CMIP5 RCP8.5 变暖情景驱动的未来试验 (2081−2100) . 结果显示, 在RCP8.5变暖情景下北半球中高纬陆地净生态系统生产力季节幅度整体增加, 这是因为陆地净生态系统生产力的月最大值增加且月最小值减小. 最大 (最小) 陆地净生态系统生产力的增加 (减小) 是由于总初级生产力的增加强 (弱) 于生态系统总呼吸. 总初级生产力和生态系统总呼吸的变化都主要受地表气温和植被动态的驱动. 本工作强调了植被动态对北半球中高纬陆地生态系统碳循环的关键调制作用, 也强调了在地球系统模式中包含全球植被动力学模式的重要性.