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1.
不同强度火干扰下盘古林场天然落叶松林的空间结构   总被引:4,自引:0,他引:4  
倪宝龙  刘兆刚 《生态学报》2013,33(16):4975-4984
基于2011年7月大兴安岭外业调查数据以林隙为主要研究对象,选取景观生态学中斑块类型指数分析样地内林隙状况,并结合林木分布状态,分析不同强度林火干扰对天然落叶松林空间结构的影响。结果表明:在受中度林火干扰的林分内,只保留了少量的落叶松中径木、大径木,先锋树种在林分内呈现聚集分布;在未受林火干扰的林分和受林火轻微干扰的林分内,天然落叶松均呈现显著聚集分布;由于受到不同强度的林火干扰,林下区域与林隙区域出现不同程度的相互转化,林分空间结构发生了改变。林分按照所受林火干扰强度的递减,在同一时间不同空间上表现出了森林循环过程中所经历的林隙阶段状态、建立阶段状态、成熟阶段状态。  相似文献   

2.
We modelled the population dynamics of two types of plants with limited dispersal living in a lattice structured habitat. Each site of the square lattice model was either occupied by an individual or vacant. Each individual reproduced to its neighbors. We derived a criterion for the invasion of a rare type into a population composed of a resident type based on a pair-approximation method, in which the dynamics of both average densities and the nearest neighbor correlations were considered. Based on this invasibility criterion, we showed that, when there is a tradeoff between birth and death rates, the evolutionarily stable type is the one that has the highest ratio of birth rate to mortality. If these types are different species, they form segregated spatial patterns in the lattice model in which intraspecific competitive interactions occur more frequently than interspecific interactions. However, stable coexistence is not possible in the lattice model contrary to results from completely mixed population models. This clearly shows that the casual conclusion, based on traditional well mixed population models, that different species can coexist if intraspecific competition is stronger than interspecific competition, does not hold for spatially structured population models.  相似文献   

3.
Although some studies have demonstrated temporal patterns of changes in spatial structure during forest development, few studies have examined the variability of spatial structure between stands at the same developmental stage. In the present study, we investigated variations of spatial structure between sites at the same developmental stage for three developmental stages (sapling, intermediate, and mature) in a wave-regenerated Abies veitchii and Abies mariesii forest. The spatial structure of tree heights in each plot was analyzed by using the mark correlation and mark variogram methods, and the pattern of tree locations in each plot was analyzed by using the pair-correlation function. Analysis of the spatial height structure indicated that a size hierarchy between neighboring trees (a local size hierarchy) generally did not develop at the sapling stage. A local size hierarchy developed in most plots during the two later stages. There was no obvious difference among developmental stages in the spatial pattern of tree locations because of the large variation within each stage. Our results demonstrate that large variation in spatial structure existed between sites in the wave-regenerated Abies forest, even at the same developmental stage. The variability in spatial structure confirmed the importance of stochastic factors in forest dynamics.  相似文献   

4.
关帝山天然次生针叶林林隙径高比   总被引:2,自引:0,他引:2  
符利勇  唐守正  刘应安 《生态学报》2011,31(5):1260-1268
林隙径高比(DEG/H)是指林隙直径与林隙高度的比值。它是林隙的一个主要特征因子,是研究森林动态及评价森林采伐强度的一个重要指标。以关帝山三种天然次生针叶林(华北落叶松、云杉、油松林)林隙作为研究对象,分析了3种林分林隙径高比结构,结果为:云杉林林隙径高比DEG/H以0.6-1.6之间分布最多,占81.82%,油松林林隙径高比主要分布在0.8-1.6之间,占70.72%。华北落叶松林林隙径高比主要分布在0.4-1之间,占97.06%;通过林隙大小与林隙下幼树数量及林隙敏感度与幼树密度之间的散点分布趋势对林隙大小和林隙敏感度两个特征因子进行比较分析,结果为:林隙大小与林隙下幼树数量之间的散点分布无规律,很难反映各自林隙大小与幼树数量之间的具体关系。而DEG/H与幼树密度之间的散点分布很有规律,能较好的反映幼树密度与林隙径高比之间的关系;利用线性模型、对数模型以及二阶多项分布模型分别对幼树密度和DEG/H进行回归分析,并利用各自模型的相关系数、参数P值对它们进行比较,结果为:3种模型都可以用来拟合3种林分的幼树密度和林隙敏感度,其中对数模型拟合效果最好。  相似文献   

5.
The tree community of both canopy gaps and mature forest was surveyed in a 5 ha plot of cloud forest in the Ibitipoca Range, south-eastern Brazil, aiming at: (a) comparing the tree community structure of canopy gaps with that of three strata of the mature forest, and (b) relating the tree community structure of canopy gaps with environmental and biotic variables. All saplings of canopy trees with 1–5 m of height established in 31 canopy gaps found within the plot were identified and measured. Mature forest trees with dbh 3 cm were sampled in four 40×40 quadrats laid on the four soil sites recognised in the local soil catena. All surveyed trees were identified, measured and distributed into three forest strata: understorey (<5 m of height), sub-canopy (5.1–15 m) and canopy (15.1–30 m). The following variables were obtained for each gap: mode of formation, age, soil site, slope grade, size, canopy openness and abundance of bamboos and lianas. A detrended correspondence analysis indicated that the tree community structure of gaps in all soil sites was more similar to that of the mature forest understorey, suggesting that the bank of immatures plays an important role in rebuilding the forest canopy and that gap phases may be important for understorey shade-tolerant species. There was evidence of gap-dependence for establishment for only one canopy tree species. Both canonical correspondence analysis and correlation analysis demonstrated for a number of tree species that the distribution of their saplings in canopy gaps was significantly correlated with two variables: soil site and canopy openness. The future forest structure at each gap is probably highly influenced by both the present structure of the adjacent mature forest and the gap creation event.  相似文献   

6.
While the successional dynamics and large-scale structure of Douglas-fir forest in the Pacific Northwest region is well studied, the fine-scale spatial characteristics at the stand level are still poorly understood. Here we investigated the fine-scale spatial structure of forest on Vancouver Island, in order to understand how the three dominant species, Douglas-fir, western hemlock, and western redcedar, coexist and partition space along a chronosequence comprised of immature, mature, and old-growth stands. We quantified the changes in spatial distribution and association of the species along the chronosequence using the scale-dependent point pattern analyses pair-correlation function g(r) and Ripley's L-function. Evidence on intra- and inter-specific competition was also inferred from correlations between nearest-neighbor distances and tree size. Our results show that 1) the aggregation of Douglas-fir in old-growth was primarily caused by variation in local site characteristics, 2) only surviving hemlock were more regular than their pre-mortality patterns, a result consistent with strong intra-specific competition, 3) inter-specific competition declined rapidly with stand age due to spatial resource partitioning, and (4) tree death was spatially randomly distributed among larger overstory trees. The study highlights the importance of spatial heterogeneity for the long-term coexistence of shade-intolerant pioneer Douglas-fir and shade-tolerant western hemlock and western redcedar.  相似文献   

7.
Invasion by generalist tree species can cause biotic homogenization, and such community impoverishment is likely more important in rare forest types. We quantified changes in tree diversity within Carolinian (range in Central Hardwood Forest), central (range in Central Hardwood Forest and Northern Hardwood‐Conifer Forest), and northern species [range reached Northern‐Conifer‐Hardwood/closed Boreal (spruce‐Fir) Forest] in an old forest tract in southern Canada at points surveyed 24 years apart. We asked: How did mature tree and sapling composition and abundance change for the three species’ groups? Did those changes lead to biotic homogenization? Can species’ changes be explained by community traits? We tested for differences in temporal and spatial tree β‐diversity, as well as forest composition and structure, using univariate/multivariate analyses and a community trait‐based approach to identify drivers of change. Major increases occurred in abundance for mature Acer rubrum (northern), while other species decreased (Fraxinus americana, Populus grandidentata); declines were found in A. saccharinum (central) and Cornus florida (Carolinian). Species composition of saplings, but not mature trees, changed due to replacement; no evidence for biotic homogenization existed in either cohort. As a group, northern mature tree species increased significantly, while central species decreased; saplings of pooled Carolinian species also declined. Shade tolerance in mature trees increased, reflecting successional changes, while drought tolerance decreased, perhaps due to changing temperatures, altered precipitation or ground water levels. Saplings showed declines in all traits, probably because of compositional change. Our results demonstrated that saplings can more closely reflect change in forest dynamics than mature trees, especially over short time periods. Based on sapling trends, this remnant could ultimately transition to a mesophytic hardwood stand dominated by A. rubrum and other shade‐tolerant species, creating a more homogeneous forest. While encouraging regeneration for Carolinian and central tree species could ensure high levels of diversity are conserved in the future, it is important to balance this with the primary management goal of maintaining the forest''s old‐growth characteristics.  相似文献   

8.
In the Sierra Nevada, distributions of forest tree species are largely controlled by the soil-moisture balance. Changes in temperature or precipitation as a result of increased greenhouse gas concentrations could lead to changes in species distributions. In addition, climatic change could increase the frequency and severity of wildfires. We used a forest gap model developed for Sierra Nevada forests to investigate the potential sensitivity of these forests to climatic change, including a changing fire regime. Fuel moisture influences the fire regime and couples fire to climate. Fires are also affected by fuel loads, which accumulate according to forest structure and composition. These model features were used to investigate the complex interactions between climate, fire, and forest dynamics. Eight hypothetical climate-change scenarios were simulated, including two general circulation model (GCM) predictions of a 2 × CO2 world. The response of forest structure,species composition, and the fire regime to these changes in the climate were examined at four sites across an elevation gradient. Impacts on woody biomass and species composition as a result of climatic change were site specific and depended on the environmental constraints of a site and the environmental tolerances of the tree species simulated. Climatic change altered the fire regime both directly and indirectly. Fire frequency responded directly to climate's influence on fuel moisture, whereas fire extent was affected by changes that occurred in either woody biomass or species composition. The influence of species composition on fuel-bed bulk density was particularly important. Future fires in the Sierra Nevada could be both more frequent and of greater spatial extent if GCM predictions prove true. Received 5 May 1998; accepted 4 November 1998.  相似文献   

9.
小兴安岭阔叶红松混交林林隙特征   总被引:3,自引:1,他引:2  
对小兴安岭阔叶红松混交林林隙基本特征进行了研究。结果表明:林隙的线状密度为31.78个/km,冠空隙和扩展林隙所占的面积比例分别为15.71%和30.78%;冠空隙的年干扰频率为0.46%,干扰轮回期约为434.8a。冠空隙的大小变化在42.12—372.52m2之间,平均为153.37m2;扩展林隙的大小变化在98.65m2—633.10m2之间,平均为300.44m2。冠空隙和扩展林隙面积分布格局均符合Weibull分布。林隙形成方式主要为干基折断,占总形成木总数的35.29%,其次为掘根风倒,占28.43%。平均每个林隙的形成木为4.98株,由红松、白桦、枫桦、冷杉形成,径级在20—30 cm之间,高度在15—30 m之间。冠空隙的直径与高度比值的相对频率的分布呈单峰型曲线,当比值为0.30—0.45时,出现峰值;而扩展林隙的直径与高度比值的相对频率的分布呈双峰型曲线,当比值分别为0.75—0.90和1.05—1.15时,出现峰值。林隙边缘木胸径级的多度分布和高度级多度分布符合Weibull分布,但不符合正态分布。约13.41%的边缘木未出现偏冠现象,偏冠率在0.5—0.7之间的边缘木占70.49%。  相似文献   

10.
森林动态模型概论   总被引:18,自引:0,他引:18  
讨论了模拟森林林分动态变化的模型,并把模型分为森林生长模型和演替模型。森林生长模型包括:全林分模型、林分级模型和单木模型;演替模型包括马尔可夫类模型和林窗模型。文中给出了演替模型的基本原理和适用性,在比较早期和最新发展的林窗模型后,叙述了林窗模型的新进展。生长和演替模型的结构和数据要求不同决定了它们的在时间和空间上的适应性,最后指出模型将向综合总体方向发展  相似文献   

11.
讨论了模拟森林林分动态变化的模型,并把模型分为森林生长模型和演替模型。森林生长模型包括:全林分模型、林分级模型和单木模型;演替模型包括马尔可夫类模型和林窗模型。文中给出了演替模型的基本原理和适用性,在比较早期和最新发展的林窗模型后,叙述了林窗模型的新进展。生长和演替模型的结构和数据要求不同决定了它们的在时间和空间上的适应性,最后指出模型将向综合总体方向发展。  相似文献   

12.
辽河源不同龄组油松天然次生林生物量及空间分配特征   总被引:1,自引:0,他引:1  
油松是中国暖温带区域主要的森林植被,精确计算油松天然林生物量及准确表征空间分布特征对其在固碳释氧、林木积累营养物质等方面的生态服务功能评估具有重要意义。目前,国内基本上没有进行油松天然次生林生物量及空间分配在一个年龄序列上的研究。研究的主要目的是准确估算河北省平泉县辽河源自然保护区4个龄组油松天然次生林林分各组分的生物量,并揭示生物量在空间的分配特征。在每种林分内,林下植被层(灌木和草本)和凋落物层生物量通过样地调查和全挖取样的方法计算。基于胸径(DBH)和树高(H)的异速生长方程则用于计算乔木层生物量。结果表明:(1)林分生物量大小排序为:成熟林(397.793 t/hm2)近熟林(242.188 t/hm2)中龄林(203.801 t/hm2)幼龄林(132.894 t/hm2);(2)乔木层生物量成熟林(373.128 t/hm2)近熟林(224.991 t/hm2)中龄林(187.750 t/hm2)幼龄林(119.169 t/hm2)。地上部分各组分生物量大小关系略有差异,幼龄林和近熟林为:干根枝叶干皮球果,而中龄林和成熟林则是干根枝干皮叶球果。干生物量对于各龄组乔木层生物量来说是最大的贡献者,所占比例表现为:中龄林(66.25%)近熟林(64.38%)成熟林(62.09%)幼龄林(38.41%),而贡献较小的球果则是成熟林(1.02%)幼龄林(0.88%)近熟林(0.72%)中龄林(0.53%)。根系总生物量在18.315 t/hm2(中龄林)—44.849 t/hm2(成熟林)之间,其组分生物量大小整体上表现为:根桩粗根大根细根小细根;(3)灌木层生物量成熟林(0.861 t/hm2)近熟林(0.790 t/hm2)中龄林(0.559 t/hm2)幼龄林(0.401 t/hm2),各组分生物量大小为根茎叶;(4)草本层生物量幼龄林(3.058 t/hm2)近熟林(2.017 t/hm2)中龄林(1.220 t/hm2)成熟林(1.181 t/hm2),地下部分生物量均大于地上部分;(5)凋落物层生物量成熟林(22.623 t/hm2)近熟林(14.390 t/hm2)中龄林(14.272 t/hm2)幼龄林(10.265 t/hm2),各层生物量大小为:未分解层半分解层全分解层。(6)在各层次生物量的比较中,4个龄组均表现为乔木层凋落物层草本层灌木层。其中,幼龄林乔木层生物量占89.67%、中龄林占92.13%、近熟林占92.90%,成熟林占93.80%。  相似文献   

13.
Canopy gaps are evidence of disturbances on forest landscapes. A forest stand is in constant flux, with long stretches of biomass accumulation punctuated by episodic disturbances. We used multitemporal airborne laser scanning data to compare the gap dynamics of four Amazon forest sites. We assessed gap dynamics over 1.9–3.8 years between 2017 and 2020 at sites in the central, central eastern, southeastern, and northeastern regions of the Brazilian Amazon, over areas ranging from 590 to 1205 ha at each site. Gap size ranged from a minimum of 10 m2 to a maximum of about 10,000 m2. We analyzed four stages of gap dynamics: formation, expansion, persistence, and recovery based on two consecutive airborne laser scanning surveys. The gap fraction at our study sites varied between 1.26% and 7.84%. All the sites have similar proportion of gaps among gap size classes. What notably differed among sites was not the gap size-distribution, but the relative importance of stages of gap dynamics. Expansion and persistence rates ranged from 12 to 118 m2 ha−1. The gap formation rate (formation + expansion) was lower than the recovery rate for three of the four study sites. In contrast, the southeastern site has 1.44 times more area in formation and expansion compared to gap recovery. Over the 2–4 years interval of our study, no site was close to steady state. Multitemporal analyses of large areas over many years are needed to improve our understanding of tropical forest dynamics.  相似文献   

14.
We asked the following questions regarding gap dynamics and regeneration strategies in Juniperus-Laurus forests: How important are gaps for the maintenance of tree diversity? What are the regeneration strategies of the tree species? Thirty canopy openings were randomly selected in the forest and in each the expanded gap area was delimited. Inside expanded gaps the distinction was made between gap and transition zone. In the 30 expanded gaps a plot, enclosing the gap and transition zone, was placed. In order to evaluate the differences in regeneration and size structure of tree species between forest and expanded gaps, 30 control plots were also delimited in the forest, near each expanded gap. In the 60 plots the number of seedlings, saplings, basal sprouts and adults of tree species were registered. Canopy height and width of adult individuals were also measured. The areas of the 30 gaps and expanded gaps were measured and the gap-maker identified. Juniperus-Laurus forests have a gap dynamic associated with small scale disturbances that cause the death, on average, of two trees, mainly of Juniperus brevifolia. Gap and expanded gap average dimensions are 8 and 25 m2, respectively. Gaps are of major importance for the maintenance of tree diversity since they are fundamental for the regeneration of all species, with the exception of Ilex azorica. Three types of regeneration behaviour and five regeneration strategies were identified: (1) Juniperus brevifolia and Erica azorica are pioneer species that regenerate in gaps from seedlings recruited after gap formation. However, Juniperus brevifolia is a pioneer persistent species capable of maintaining it self in the forest due to a high longevity and biomass; (2) Laurus azorica and Frangula azorica are primary species that regenerate in gaps from seedlings or saplings recruited before gap formation but Laurus azorica is able to maintain it self in the forest through asexual regeneration thus being considered a primary persistent species; (3) Ilex azorica is a mature species that regenerates in the forest.  相似文献   

15.
Zhang J  Hao Z Q  Li B H  Ye J  Wang X G  Yao X L 《农业工程》2008,28(6):2445-2454
To explore the composition and spatio-temporal dynamics of seed rain in broad-leaved Korean pine (Pinus koraiensis) mixed forest, 150 seed traps were set up in a 25 hm2 plot in Changbai Mountain. Seeds, fruits, anthotaxy and others in seed traps were collected, identified and divided into 4 types. From 2005 to 2006, we collected 47 different types. Total number of seeds and fruits was 121291, including 23147 mature seeds and fruits (19.1% of the total). Tilia amurensis and Fraxinus mandshurica, with the most seeds and fruits, accounted for 90% of the total. The analysis on seasonal dynamics of seed rain showed that there were the largest number of seeds and fruits between July and October, which were composed of immature seeds and fruits. In mid-October, mature seeds and fruits reached their peak, but immature seeds and fruits still accounted for high proportion. There were 91 traps that contained 100–200 mature seeds and fruits, and one trap without any mature seed or fruit. The largest number of species found in a trap was 7, and usually 3 or 4 species were found in most of the traps. There were obvious relationships between spatial patterns of mature seeds and fruits and their parent trees, indicating that their mature seeds and fruits were not dispersed far from their parent trees.  相似文献   

16.
Abstract. We tested whether interspecific variation in tree seedling establishment in canopy gaps was significantly related to interspecific variation in tree density, for seven deciduous forest tree species (Quercus alba, Hamamelis virginiana, Acer rubrum, Sassafras albidum, Quercus rubra, Prunus serotina, Ostrya virginiana). For each species, seedling establishment was calculated as the difference in seedling density before experimental gap creation versus three years after gap creation. In each of the six experimentally-created gap types (33 % or 66 % removal of tree basal area from 0.01-ha, 0.05-ha or 0.20-ha patches), differences in seedling establishment among species were significantly related to differences in their density in the tree canopy. A regression model with loge tree density as the independent variable accounted for between 93 % and 98 % of interspecific variation in seedling establishment. Our results provide empirical support for models of tree dynamics in gaps that assume seedling establishment depends on canopy tree density.  相似文献   

17.
We point out a general problem in fitting continuous time spatially explicit models to a temporal sequence of spatial data observed at discrete times. To illustrate the problem, we examined the continuous time Markov model for forest gap dynamics. A forest is assumed to be apportioned into discrete cells (or sites) arranged in a regular square lattice. Each site is characterized as either a gap or a non-gap site according to the vegetation height of trees. The model incorporates the influence of neighboring sites on transition rate: transition rate from a non-gap to a gap site increases linearly with the number of neighbors that are currently in the gap state, and vice versa. We fitted the model to the spatiotemporal data of canopy height observed at the permanent plot in Barro Colorado Island (BCI). When we used the approximate maximum likelihood method to estimate the parameters of the model, the estimated transition rates included a large bias-in particular, the strength of interaction between nearby sites was underestimated. This bias originated from the assumption that each transition between two observation times is independent. The interaction between sites at local scale creates a long chain of transitions within a single census interval, which violates the independence of each transition. We show that a computer-intensive method, called Monte Carlo bias correction (MCBC), is very effective in removing the bias included in the estimate. The global and local gap densities measuring spatial aggregation of gap sites were computed from simulated and real gap dynamics to assess the model. When the approximate likelihood estimates were applied to the model, the predicted local gap density was clearly lower than the observed one. The use of MCBC estimates, suggesting a strong interaction between sites, improved this discrepancy.  相似文献   

18.
Tropical agro-forest landscapes are potentially valuable reserves of forest genetic resources for forestry and restoration of degraded forests. The Dipterocarpaceae is a dominant Southeast Asian family of tree species of global significance for the tropical timber industry. Very little information exists about how effective human modified landscapes are for conserving genetic diversity in dipterocarp species. This study provides a baseline for understanding how fragmented agro-forest landscapes in India sustain forest genetic resources in an endemic dipterocarp tree. We compare genetic diversity and fine-scale spatial genetic structure (FSGS) in the threatened tree species Vateria indica within an isolated and a continuous forest site in the Western Ghats, South India. We place these results in the context of dipterocarps from both the Seychelles and Borneo. Parentage analysis of 694 progeny using twelve nuclear microsatellite markers is applied to estimate pollen and seed dispersal. Using a nursery trial we evaluate effects of inbreeding on growth performance. Our results show that levels of FSGS, and gene dispersal are comparable between a small isolated and a large continuous site of V. indica. Realized long-distance pollen flow into the isolated patch appears to help maintaining genetic diversity. The nursery experiment suggests that selection favours outbred progeny. Individuals of V. indica in close proximity appear less related to each other than in another highly fragmented and endangered dipterocarp species from the Seychelles, but more related than in three dipterocarp species studied in continuous forest in Borneo. We discuss the wider implications of our findings in the context of conservation and restoration of dipterocarp forest genetic resources in fragmented populations.  相似文献   

19.
Question: Are canopy gap dynamics responsible for driving the structural and compositional changes that have occurred over a 26‐year period in a mature Quercus forest remnant? Location: Dobbs Natural Area, an unlogged 3.6‐ha forest preserve in west‐central Indiana, USA. Methods: We analyzed mapped permanent plot data for a site that illustrates a trend common in Quercus‐dominated forests in eastern North America, where recruitment of new stems is dominated by mesophytic, shade‐tolerant species such as Acer saccharum, rather than Quercus. We developed a GIS database from stand census measurements taken in 1974 and 2000, employing it to conduct tree‐by‐tree comparisons that allow direct determination of ingrowth, mortality and survivorship, and to relate the spatial patterns of subcanopy dynamics to canopy gap occurrence. Results: The re‐census shows modest changes in canopy composition, but much greater turnover in the subcanopy. Nearly half of all individuals originally present died; much of this mortality resulted from a major decline in subcanopy Ulmus americana. While overall density remained fairly constant, the subcanopy experienced substantial ingrowth of shade‐tolerant Acer saccharum, Fagus grandifolia, and Tilia americana. Canopy gaps, although forming at rates in the upper range of regional averages, did not significantly benefit subcanopy populations of Quercus spp. or most other taxa with limited shade tolerance. Conclusions: Canopy gaps play a minor role in driving the recent demographic trends of this stand. The spatial and temporal scales of light availability in gaps do not support regeneration of most shade‐intolerant species. Compositional change parallels a historical shift in light regimes.  相似文献   

20.
Aim This paper describes the forest gap model, FAREAST, its testing and its application to simulating the distribution, composition and dynamics of forests in eastern Eurasia. Location The FAREAST model is tested in north‐eastern China, initially for forests on the elevational gradient of Changbai Mountain, which is located on the border of the People's Republic of China and the Democratic People's Republic of Korea. Subsequently, the model is inspected regionally for other northern Chinese mountains and, finally, it is applied to predict subcontinental forest communities in the Russian Far East. Boreal larch (Larix spp.) forests cover much of the 6 million km2 of eastern Eurasia. Mixed broad‐leaved tree species/Korean pine (Pinus koraiensis) forests and spruce/fir (Picea/Abies) forests also occupy considerable areas. Methods The model is tested using three types of information: (1) direct species composition comparisons between simulated and observed mature forests at the same locations; (2) forest type comparisons between simulated and observed forests along altitudinal gradients of several different mountains; and (3) comparison with forest stands in different succession stages of simulated forests. Results Model comparisons with independent data indicate that the FAREAST model is capable of representing many of the broad features of the forests of north‐eastern China. After regional model validation in the north‐eastern region of China, geographical model applications were developed for the forests of the Russian Far East. In simulations at 31 different sites distributed across the entire Russian Far East and including a wide variety of natural forests, the model demonstrates an ability to reproduce observed vegetation pattern. The model simulations are correct with respect to our criteria for 23 of the 31 sites, and there are close results for three other sites. Among the five sites that are incorrectly predicted, four simulations can be corrected by adding a simple assumption to the model for permafrost effects on water balance. Main conclusions Continental‐scale forest cover can be simulated using a forest gap model to represent individual–plant interactions with one another, and their environment, and with parameters that describe the biology of each tree species. It appears that such a model, validated relatively locally (in this case, in north‐eastern China), can then be applied over a much larger region. These results further imply that the Russian Far East forests can be regarded as a natural geographical expansion of north‐eastern Chinese forests. In both regions, forests share not only similar species compositions, but also similar underlying causes of forest successional dynamics.  相似文献   

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