2000—2015年中国东北森林生产力和碳素利用率的时空变异

中国东北森林生态系统是重要的碳汇功能区,也是对环境变化响应的敏感区,分析其植被生产力和碳素利用效率的变化特征及其对气候变化的响应对于区域碳收支的准确评估和预测具有重要意义.本研究利用MODIS的长期监测数据,结合植被类型分布数据,对中国东北森林生态系统2000—2015年生产力(净初级生产力NPP、总初级生产力GPP)和碳素利用率(NPP/GPP)时空变化特征进行分析.结果表明: 研究期间,东北森林生态系统平均NPP和GPP分别为346.4和773 g C·m^-2·a^-1,平均NPP/GPP为0.45.不同森林类型的NPP和GPP依次为针阔混交林>落叶阔叶林>针叶林,NPP/GPP在不同森林类型间无显著差异.NPP和GPP呈现出东南高、西北低的空间分布特点.2000—2015年间,东北森林生态系统NPP、GPP和NPP/GPP呈波动增加趋势,固碳能力逐步增强.NPP、GPP和NPP/GPP的变化趋势和变化速率表现出空间差异性,在大兴安岭南部地区显著增加,在大兴安岭北部地区显著下降,其余区域呈微弱增加趋势.与气候因子的相关性分析表明,年降水量的增加是驱动东北森林生态系统NPP、GPP和NPP/GPP波动增加的主要因素.     

Productivity overshadows temperature in determining soil and ecosystem respiration across European forests

This paper presents CO₂ flux data from 18 forest ecosystems, studied in the European Union funded EUROFLUX project. Overall, mean annual gross primary productivity (GPP, the total amount of carbon (C) fixed during photosynthesis) of these forests was 1380 ± 330 gC m^?2 y^?1 (mean ±SD). On average, 80% of GPP was respired by autotrophs and heterotrophs and released back into the atmosphere (total ecosystem respiration, TER = 1100 ± 260 gC m^?2 y^?1). Mean annual soil respiration (SR) was 760 ± 340 gC m^?2 y^?1 (55% of GPP and 69% of TER). Among the investigated forests, large differences were observed in annual SR and TER that were not correlated with mean annual temperature. However, a significant correlation was observed between annual SR and TER and GPP among the relatively undisturbed forests. On the assumption that (i) root respiration is constrained by the allocation of photosynthates to the roots, which is coupled to productivity, and that (ii) the largest fraction of heterotrophic soil respiration originates from decomposition of young organic matter (leaves, fine roots), whose availability also depends on primary productivity, it is hypothesized that differences in SR among forests are likely to depend more on productivity than on temperature. At sites where soil disturbance has occurred (e.g. ploughing, drainage), soil espiration was a larger component of the ecosystem C budget and deviated from the relationship between annual SR (and TER) and GPP observed among the less‐disturbed forests. At one particular forest, carbon losses from the soil were so large, that in some years the site became a net source of carbon to the atmosphere. Excluding the disturbed sites from the present analysis reduced mean SR to 660 ± 290 gC m^?2 y^?1, representing 49% of GPP and 63% of TER in the relatively undisturbed forest ecosystems.     

China's crop productivity and soil carbon storage as influenced by multifactor global change

Much concern has been raised about how multifactor global change has affected food security and carbon sequestration capacity in China. By using a process‐based ecosystem model, the Dynamic Land Ecosystem Model (DLEM), in conjunction with the newly developed driving information on multiple environmental factors (climate, atmospheric CO₂, tropospheric ozone, nitrogen deposition, and land cover/land use change), we quantified spatial and temporal patterns of net primary production (NPP) and soil organic carbon storage (SOC) across China's croplands during 1980–2005 and investigated the underlying mechanisms. Simulated results showed that both crop NPP and SOC increased from 1980 to 2005, and the highest annual NPP occurred in the Southeast (SE) region (0.32 Pg C yr^?1, 35.4% of the total NPP) whereas the largest annual SOC (2.29 Pg C yr^?1, 35.4% of the total SOC) was found in the Northeast (NE) region. Land management practices, particularly nitrogen fertilizer application, appear to be the most important factor in stimulating increase in NPP and SOC. However, tropospheric ozone pollution and climate change led to NPP reduction and SOC loss. Our results suggest that China's crop productivity and soil carbon storage could be enhanced through minimizing tropospheric ozone pollution and improving nitrogen fertilizer use efficiency.     

Responses of vegetation structure and primary production of a forest transect in eastern China to global change

Aim A regional model of vegetation dynamics was enhanced to include biogeochemical cycling of nitrogen and was then applied to a forest transect in east China (FTEC) in order to investigate the responses of the transect to possible global change. Location Eastern China. Methods Biomass and nitrogen concentration of green and nongreen portions of vegetation, moisture contents of three soil layers, and total and available soil nitrogen are included as state variables in the enhanced model. The model was parameterized and validated against field observations of biomass, productivity, plant and soil nitrogen concentration, nitrogen uptake, a vegetation index derived from satellite remote sensing and digital maps of vegetation and soil distributions along a forest transect in eastern China (FTEC). The model was applied to FTEC in order to investigate the responsive characteristics of the ecosystems to global climatic change. Scenarios of climate change under doubled CO₂ produced by seven general circulation models (GCM) were used to drive the model. Results The simulations indicated that the model is capable of simulating accurately potential vegetation distribution and net primary productivity under contemporary climatic conditions. The simulations for GCM‐projected future climate scenarios with doubled atmospheric CO₂ concentration predicted that broadleaf forests would increase, but conifer forests, shrubs and grasses would decrease; and that deciduous forests would have the largest relative increase, but evergreen shrubs would have the largest decrease. Conclusions The overall effects of doubling CO₂ and climatic changes on FTEC were to produce an increased net primary productivity (NPP) at equilibrium for all seven GCM scenarios. The inclusion of nitrogen dynamics in the model imposes more constraint on the responses of FTEC to climatic change than the previous version of the model without nitrogen dynamics. Temperature exerts a stronger control on NPP than precipitation, as indicated by the negative correlations between NPP and temperature. The southern portion of FTEC, at latitudes less than 33 °N, show much larger increases in annual NPP than in the north. However, the predicted range of NPP increases is much larger in the north than in the south.     

基于集成生物圈模型的南岭不同植被类型碳收支研究

广东南岭保存着世界上同纬度带上最完整的亚热带植被,森林资源丰富,具有巨大的固碳潜力。然而,目前该地区不同森林植被类型的碳收支年积累量特征及月动态规律尚不明确。选择广东南岭国家级自然保护区内沟谷常绿阔叶林、山地常绿阔叶林、针阔叶混交林和山顶常绿阔叶矮林4种典型森林植被为研究对象,运用集成生物圈模型(IBIS)对其2020年总初级生产力(GPP)、净初级生产力(NPP)、净生态系统生产力(NEP)和土壤异养呼吸(R_h)进行模拟,利用样地调查数据对NPP模拟结果进行验证,分析该地区不同植被类型的碳收支年积累量特征及月变化特征。研究结果表明,2020年南岭不同植被类型GPP、NPP、NEP和R_h的平均值分别为1.709、0.718、0.596和0.123 kg C m^-2 a^-1,4种植被类型中GPP最高的是沟谷常绿阔叶林,NPP、NEP最高的是山地常绿阔叶林,山顶常绿阔叶矮林的GPP、NPP和NEP均相对较低。南岭不同植被类型全年各月均表现出碳汇(NEP>0),逐月NPP和NEP均表现为双峰变化规律...     

吉林省落叶松林净初级生产力时空特征及其对气候变化的响应

为评估吉林省落叶松林的生产力现状并为我国森林生态系统生产力和植被监测研究提供基础数据,以吉林省落叶松林为研究对象,基于吉林省及其周边100 km范围内41个气象站点资料,采用LPJ-DGVM模型模拟了2000—2019年吉林省落叶松林近20年的净初级生产力,并采用线性回归趋势分析、变异系数、Hurst指数和相关性分析法对其时空变化、稳定性及其与气候因子的相关关系进行了分析。结果表明：(1)2000—2019年吉林省落叶松林年均净初级生产力(NPP)为592 g C m^-2 a^-1,年均增长率为2.81%,随时间推移呈现波动增长的趋势(β=14.55,R~2=0.784,P<0.01)。(2)NPP变异系数为0.07—2.33,均值为0.48,除幼龄林外,整体波动较小。Hurst指数介于0.441—0.849之间,均值为0.612,未来吉林省落叶松林NPP呈增加趋势。(3)吉林省落叶松林NPP存在明显的空间异质性,北部和南部区域NPP较高,是近20年NPP增长较快的区域。(4)2000—2019年吉林省落叶松林年均NPP与年总降水、生长季...     

基于VPM模型的长白山自然保护区植被总初级生产力动态变化

总初级生产力(GPP)是碳循环的重要参数,它的准确估算对碳循环及全球气候变化研究有重要作用.利用VPM模型及2000—2015年MOD09A1数据/气候因子的空间数据,对长白山自然保护区的植被GPP进行模拟.结果表明: 2000—2015年,保护区GPP年均值为1203 g C·m^-2·a^-1,GPP呈极显著趋势增长.森林植被GPP年际增长变化在不同植被垂直带下没有显著区别,但从高山苔原带往上,GPP年际增长明显减小.GPP与降水的年际相关性不显著,与温度的正相关关系集中分布在阔叶红松林带和高山苔原带.春季气温对GPP影响最大,有80%像元显示与气温呈正相关.GPP与温度的年际相关性明显高于降水.     

基于景观尺度过程模型的长白山净初级生产力空间分布影响因素分析

对长白山自然保护区的净初级生产力(NPP)的空间分布格局进行了模拟,对它们与环境因子和植被因子间的相互关系进行了分析．结果表明,1995年NPP的模拟值平均为0．680kgC·m^-2·年^-1,变幅为0．105-1．241kgC·m^-2·年^-1(82．1％),其中阔叶红松林的NPP最高(1．084kgC·m^-2·年^-1)．环境条件决定了长白山植被年NPP空间分布的大趋势．土壤含水量对NPP的限制最大,呈负相关关系(R=-0.65),长白山植物生长一般不存在水分不足的问题．植被的NPP与LAI高度正相关(R＝0．81),当LAI增大到4-5m^2·m^-2时,NPP出现饱和．植被的NPP与冠层蒸腾量呈显著的正相关关系(R＝0．77)．岳桦林和阔叶林对环境因子、LAI和冠层蒸腾的响应与其它植被有较大差异。     

Assessing the response of forest productivity to climate extremes in Switzerland using model–data fusion

The response of forest productivity to climate extremes strongly depends on ambient environmental and site conditions. To better understand these relationships at a regional scale, we used nearly 800 observation years from 271 permanent long‐term forest monitoring plots across Switzerland, obtained between 1980 and 2017. We assimilated these data into the 3‐PG forest ecosystem model using Bayesian inference, reducing the bias of model predictions from 14% to 5% for forest stem carbon stocks and from 45% to 9% for stem carbon stock changes. We then estimated the productivity of forests dominated by Picea abies and Fagus sylvatica for the period of 1960–2018, and tested for productivity shifts in response to climate along elevational gradient and in extreme years. Simulated net primary productivity (NPP) decreased with elevation (2.86 ± 0.006 Mg C ha^?1 year^?1 km^?1 for P. abies and 0.93 ± 0.010 Mg C ha^?1 year^?1 km^?1 for F. sylvatica). During warm–dry extremes, simulated NPP for both species increased at higher and decreased at lower elevations, with reductions in NPP of more than 25% for up to 21% of the potential species distribution range in Switzerland. Reduced plant water availability had a stronger effect on NPP than temperature during warm‐dry extremes. Importantly, cold–dry extremes had negative impacts on regional forest NPP comparable to warm–dry extremes. Overall, our calibrated model suggests that the response of forest productivity to climate extremes is more complex than simple shift toward higher elevation. Such robust estimates of NPP are key for increasing our understanding of forests ecosystems carbon dynamics under climate extremes.     

Relationships among net primary productivity, nutrients and climate in tropical rain forest: a pan-tropical analysis

Tropical rain forests play a dominant role in global biosphere-atmosphere CO(2) exchange. Although climate and nutrient availability regulate net primary production (NPP) and decomposition in all terrestrial ecosystems, the nature and extent of such controls in tropical forests remain poorly resolved. We conducted a meta-analysis of carbon-nutrient-climate relationships in 113 sites across the tropical forest biome. Our analyses showed that mean annual temperature was the strongest predictor of aboveground NPP (ANPP) across all tropical forests, but this relationship was driven by distinct temperature differences between upland and lowland forests. Within lowland forests (相似文献   

Forest carbon use efficiency: is respiration a constant fraction of gross primary production?

Carbon‐use efficiency (CUE), the ratio of net primary production (NPP) to gross primary production (GPP), describes the capacity of forests to transfer carbon (C) from the atmosphere to terrestrial biomass. It is widely assumed in many landscape‐scale carbon‐cycling models that CUE for forests is a constant value of ∼0.5. To achieve a constant CUE, tree respiration must be a constant fraction of canopy photosynthesis. We conducted a literature survey to test the hypothesis that CUE is constant and universal among forest ecosystems. Of the 60 data points obtained from 26 papers published since 1975, more than half reported values of GPP that were not estimated independently from NPP; values of CUE calculated from independent estimates of GPP were greater than those calculated from estimates of GPP derived from NPP. The slope of the relationship between NPP and GPP for all forests was 0.53, but values of CUE varied from 0.23 to 0.83 for different forest types. CUE decreased with increasing age, and a substantial portion of the variation among forest types was caused by differences in stand age. When corrected for age the mean value of CUE was greatest for temperate deciduous forests and lowest for boreal forests. CUE also increased as the ratio of leaf mass‐to‐total mass increased. Contrary to the assumption of constancy, substantial variation in CUE has been reported in the literature. It may be inappropriate to assume that respiration is a constant fraction of GPP as adhering to this assumption may contribute to incorrect estimates of C cycles. A 20% error in current estimates of CUE used in landscape models (i.e. ranging from 0.4 to 0.6) could misrepresent an amount of C equal to total anthropogenic emissions of CO₂ when scaled to the terrestrial biosphere.     

The Bromeliad Microcosm and the Assessment of Faunal Diversity in a Neotropical Forest1

The faunas of tank bromeliads were sampled over two years in three forest types at different elevations in the Luquillo Experimental Forest, Puerto Rico, and the diversity of their animal communities compared. Bromeliad plants behaved as islands in that, within forests, the species richness and abundance of their animal communities were significantly and positively correlated with increase in plant size. The amount of canopy debris they accumulated was similarly correlated with increase in plant size. Overall diversity was lowest in the dwarf forest, where plants were uniformly small. Animal communities were stable from year to year, and could be characterised for each forest type and for compartments within the plant. They showed a pattern of high dominance, which increased with elevation (Mc-Naughton index 37, 54, and 73, respectively, for the tabonuco, palo Colorado, and dwarf forest). Alpha-diversity for sites sampled in each year reflected net primary productivity (NPP) of the forest, declining with increasing elevation when animal abundance measures were used (jackknife estimates of Simpson's diversity index 6.54 & 11.04 [tabonuco], 3.53 & 6.22 [palo Colorado], and 2.75 & 2.17 [dwarf forest]). Species richness over the two years, however, was highest in the intermediate palo Colorado forest (187 species), compared to 146 and 88 in the tabonuco and dwarf forests, respectively. These figures were close to jackknife estimates of maximum species richness. The difference in species richness between tabonuco and palo Colorado forests was significant in one year only. In addition to NPP, other factors, such as litter quality and the structural complexity of the habitat in the palo Colorado forest, may have influenced species richness. The most abundant species in individual plants were also the most widely occurring, confirming known patterns of abundance and distribution in other functional groups. Diversity within bromeliad microcosms at different elevations supported known relationships between diversity, productivity, and habitat complexity along gradients and was not related to differences in the total bromeliad habitat available for colonization.     

长白山阔叶红松林生产力随林分发育的变化

林龄是影响森林生态系统碳储量和碳通量的一个关键因子。量化森林生产力随林分发育的变化规律,对于优化林龄结构,促进资源利用最大化,更好地发挥森林在调节CO₂吸收、储存和释放中的作用十分重要。本研究采用空间代替时间法,在露水河林区设置12块不同发育阶段的阔叶红松林样地,运用经本地参数化的Biome-BGC模型,模拟了阔叶红松林净初级生产力(NPP)随林分发育的动态变化,分析了阔叶红松林NPP在4种发育情景模式下随林分发育的变化规律。结果表明: 不同龄组阔叶红松林的生物量表现为幼龄林<中龄林<成熟林<过熟林,其平均生物量分别为(224.35±20.68)、(237.23±39.96)、(259.16±19.51)和(357.57±84.74) t·hm^-2。模型模拟的不同发育阶段阔叶红松林NPP的变化范围为489.8～588 g C·m^-2·a^-1,模拟结果与MODIS观测结果有较好的一致性,反映了Biome-BGC模型模拟阔叶红松林碳通量的合理性和准确性。模型模拟的阔叶红松林NPP随林分发育呈先增加后下降的变化趋势,在中龄林时达到最高,过熟林时最低。4种阔叶红松林发育动态情景模式下的NPP变化特征表明,在起始状态为人工种植红松林的自然发育和发育过程中对阔叶树实施采伐控制的两种情景下,成熟林时期NPP最高;而在起始状态为天然次生白桦林的自然发育和经人为采伐动态控制的两种情景下,均表现为幼龄期NPP最高。     

Forest biomass,productivity and carbon cycling along a rainfall gradient in West Africa

Net Primary Productivity (NPP) is one of the most important parameters in describing the functioning of any ecosystem and yet it arguably remains a poorly quantified and understood component of carbon cycling in tropical forests, especially outside of the Americas. We provide the first comprehensive analysis of NPP and its carbon allocation to woody, canopy and root growth components at contrasting lowland West African forests spanning a rainfall gradient. Using a standardized methodology to study evergreen (EF), semi‐deciduous (SDF), dry forests (DF) and woody savanna (WS), we find that (i) climate is more closely related with above and belowground C stocks than with NPP (ii) total NPP is highest in the SDF site, then the EF followed by the DF and WS and that (iii) different forest types have distinct carbon allocation patterns whereby SDF allocate in excess of 50% to canopy production and the DF and WS sites allocate 40%–50% to woody production. Furthermore, we find that (iv) compared with canopy and root growth rates the woody growth rate of these forests is a poor proxy for their overall productivity and that (v) residence time is the primary driver in the productivity‐allocation‐turnover chain for the observed spatial differences in woody, leaf and root biomass across the rainfall gradient. Through a systematic assessment of forest productivity we demonstrate the importance of directly measuring the main components of above and belowground NPP and encourage the establishment of more permanent carbon intensive monitoring plots across the tropics.     

千烟洲马尾松人工林生态系统的碳循环模拟及模型参数的敏感性分析

应用改进后的碳水循环过程模型——景观尺度生态系统生产力过程模型(ecosystem productivity process model for landscape,EPPML)模拟了2003和2004年千烟洲马尾松人工林生态系统的碳循环过程,并对模型参数的敏感性进行了分析.结果表明:EPPML可用于模拟千烟洲马尾松人工林的碳循环过程,不仅总初级生产力(GPP)、生态系统净生产力(NEP)和生态系统总呼吸(Re)的年总值和季节变化与实测值十分吻合,而且也能反映极端天气对碳流的重要影响;千烟洲马尾松人工林生态系统具有较强的净碳吸收能力,但2003年生长最旺季的高温和重旱天气的耦合作用使其碳吸收能力明显低于2004年,2003和2004年平均NEP分别为481.8和516.6gC.m-2.a-1;马尾松生长初期的光照、生长旺期的干旱、生长末期的降水量是改变碳循环季节变化的关键气象条件;自养呼吸(Ra)与净初级生产力(NPP)的季节进程一致;异养呼吸(Rh)在年尺度上受土壤温度控制,而在月尺度上则受土壤含水量波动的影响;在生长季的丰水期,土壤含水量越大,Rh越小;而在生长季的枯水期,前两个月的降雨量越大,Rh也越大.EPPML参数中,25℃时的最大RuBP羧化速率(Vm25)、比叶面积(SLA)、最大叶N含量(LNm)、平均叶含N量(LN)、生物量与碳的转换率(C/B)对年NEP的影响最大;不同碳循环过程变量对敏感参数变化的响应也不尽相同,其中,Vm25和LN的增加能有效促进植物的碳吸收和呼吸;LN/LNm越小,对碳吸收和呼吸的抑制作用越强;C/B和SLA的增大会促进碳吸收,抑制呼吸.将全年区分为生长季与非生长季时得到的最敏感参数的结论与全年不尽相同.     

Site-level evaluation of satellite-based global terrestrial gross primary production and net primary production monitoring

Operational monitoring of global terrestrial gross primary production (GPP) and net primary production (NPP) is now underway using imagery from the satellite‐borne Moderate Resolution Imaging Spectroradiometer (MODIS) sensor. Evaluation of MODIS GPP and NPP products will require site‐level studies across a range of biomes, with close attention to numerous scaling issues that must be addressed to link ground measurements to the satellite‐based carbon flux estimates. Here, we report results of a study aimed at evaluating MODIS NPP/GPP products at six sites varying widely in climate, land use, and vegetation physiognomy. Comparisons were made for twenty‐five 1 km² cells at each site, with 8‐day averages for GPP and an annual value for NPP. The validation data layers were made with a combination of ground measurements, relatively high resolution satellite data (Landsat Enhanced Thematic Mapper Plus at ～30 m resolution), and process‐based modeling. There was strong seasonality in the MODIS GPP at all sites, and mean NPP ranged from 80 g C m^?2 yr^?1 at an arctic tundra site to 550 g C m^?2 yr^?1 at a temperate deciduous forest site. There was not a consistent over‐ or underprediction of NPP across sites relative to the validation estimates. The closest agreements in NPP and GPP were at the temperate deciduous forest, arctic tundra, and boreal forest sites. There was moderate underestimation in the MODIS products at the agricultural field site, and strong overestimation at the desert grassland and at the dry coniferous forest sites. Analyses of specific inputs to the MODIS NPP/GPP algorithm – notably the fraction of photosynthetically active radiation absorbed by the vegetation canopy, the maximum light use efficiency (LUE), and the climate data – revealed the causes of the over‐ and underestimates. Suggestions for algorithm improvement include selectively altering values for maximum LUE (based on observations at eddy covariance flux towers) and parameters regulating autotrophic respiration.     

基于遥感和过程模型的亚洲东部陆地生态系统初级生产力分布特征

利用美国环境预测中心的再分析气象资料和由GIMMS NDVI 资料生成的叶面积指数对BEPS生态模型进行驱动,模拟分析了2000-2005年亚洲东部地区总初级生产力（GPP）和总净初级生产力（NPP）的时空变化特征.在进行区域模拟计算前,使用15个站点不同生态系统的GPP观测数据及1300个样点的NPP观测数据对模型进行验证.结果表明： BEPS模型能较好地模拟不同生态系统的GPP和NPP变化,模拟的GPP与观测数据之间的R2为0.86～0.99,均方根误差（RMSE）为0.2～1.2 g C·m-2·d-1;BEPS模拟值能够解释78%的年NPP变化,其RMSE为118 g C·m-2·a-1.2000-2005年,亚洲东部地区GPP和NPP总量平均值分别为21.7和10.5 Pg C·a-1.NPP和GPP具有相似的时空变化特征.研究期间,NPP总量的变化范围为10.2～10.7 Pg C·a-1, 变异系数为2.2%.NPP由东南向西北显著减少,高值区〖JP2〗（>1000 g C·m-2·a-1）出现在东南亚海岛国家,我国的西北干旱沙漠地区为低值区（<30 g C·m-2·a-1）,〖JP〗其空间格局主要由气候因子决定.不同国家的人均NPP差异很大,其中,蒙古最高,达70217 kg C·a-1,远高于中国的人均NPP（1921 kg C·a-1）,印度的人均NPP最小,为757 kg C·a-1.     

Contrasting responses of net primary productivity to inter-annual variability and changes of climate among three forest types in northern China

Aims A lack of explicit information on differential controls on net primary productivity (NPP) across regions and ecosystem types is largely responsible for uncertainties in global trajectories of terrestrial carbon balance with changing environment. The objectives of this study were to determine how NPP of different forest types would respond to inter-annual variability of climate and to examine the responses of NPP to future climate change scenarios across contrasting forest types in northern China.Methods We investigated inter-annual variations of NPP in relation to climate variability across three forest types in northern China, including a boreal forest dominated by Larix gmelinii Rupr., and two temperate forests dominated by Pinus tabulaeformis Carr. and Quercus wutaishanica Mayr., respectively, and studied the responses of NPP in these forests to predicted changes in climate for the periods 2011–40, 2041–70 and 2070–100 under carbon emission scenarios A2 and B2 of Intergovernmental Panel on Climate Change. We simulated the responses of NPP to predicted changes in future climate as well as inter-annual variability of the present climate with the Biome-BGC version 4.2 based on site- and species-specific parameters. The modeled forest NPP data were validated against values in literature for similar types of forests and compared with inter-annual growth variations reflected by tree-ring width index (RWI) at the study sites.Important findings Inter-annual variations in modeled NPP during the period 1960–06 were mostly consistent with the temporal patterns in RWI. There were contrasting responses of modeled NPP among the three forest types to inter-annual variability of the present climate as well as to predicted changes in future climate. The modeled NPP was positively related to annual mean air temperature in the L. gmelinii forest (P < 0.001), but negatively in the P. tabulaeformis forest (P = 0.05) and the Q. wutaishanica forest (P = 0.03), while the relationships of modeled NPP with annual precipitation for the three forest types were all positive. Multiple stepwise regression analyses showed that temperature was a more important constraint of NPP than precipitation in the L. gmelinii forest, whereas precipitation appeared to be a prominent factor limiting the growth in P. tabulaeformis and Q. wutaishanica. Model simulations suggest marked, but differential increases in NPP across the three forest types with predicted changes in future climate.