The effect of herbivores and humans on the Sand Forest species of Maputaland,northern KwaZulu-Natal,South Africa

Sand Forest in the Maputaland region of KwaZulu-Natal in South Africa is deemed the most valuable, but also probably the most complex vegetation type of this part of the Maputaland–Pondoland–Albany hotspot of biodiversity. However, Sand Forest is under threat from the current human population growth in that region as well as from uncontrolled increases in wild herbivore numbers in conservation areas. The present study compares the impacts of herbivores and humans on the state of woody resources between two sites under differing utilisation regimes. Sand Forest was found to be a complex association of tree assemblages defined by different canopy and subcanopy properties. Although marked differences in the abundance of selected species were noted at the two sites, the Sand Forest remained dominated by fine-grained species under both utilisation regimes. The fine-grained nature of Sand Forest implies that regeneration depends on the creation of small canopy gaps either by natural processes, humans or elephants, while the creation of large gaps could transform it into woodland. Management of conservation areas where Sand Forest occurs should therefore concentrate efforts on regulating animal populations to levels that provide gap properties that favour forest regeneration.     

伏牛山自然保护区森林冠层结构对林下植被特征的影响

在伏牛山自然保护区典型地段设立样方,测定了森林生态系统内几种典型群落类型的冠层结构、光环境特征,调查了林下植被的特征,分析了它们之间的相互关系.结果显示:各群落的冠层结构和光环境有一定的差异,单因素方差分析表明,部分群落间的差异性达到显著水平;各群落灌木层物种丰富度、多样性和均匀度均高于草本层,而优势度正相反;线性拟合的结果表明,草本层的物种丰富度、多样性与冠下光合量子通量密度间呈极显著负相关,优势度与冠下光合量子通量密度间呈显著正相关,灌木层各参数与冠层结构特征间相关性不显著.研究表明,冠层结构的变化对草本层(包括更新幼苗)的影响显著高于灌木层.林隙/林窗或林中空地的出现可能对草本物种或其他阳性及先锋物种具有促进作用,而对优势种幼苗的萌发和定植产生负效应.推测在典型的落叶阔叶林生态系统演替进程中,林下光照强度可能不是最主要的限制因素,优势种种子的扩散、萌发和定植限制可能更重要.     

Appropriate vegetation indices for measuring the impacts of deer on forest ecosystems

Increasing deer density can cause serious degradation of forests in the Americas, Europe, and Asia. To manage deer impacts, evaluating their current impacts on forest ecosystems is necessary, usually via vegetation indices. However, the relationship between vegetation indices and absolute deer density, while taking into account tree size, snow depth, light condition, and the type of understory vegetation, has never been investigated. We examined the relationship between various vegetation indices and absolute deer density in 344 study plots in the deciduous broad-leaved forest of Yamanashi Prefecture, central Japan. In each plot, debarking and browsing, along with the coverage and maximum height of understory vegetation, were surveyed. Estimated deer densities for 82 5 × 5-km mesh units ranged from 0.8 deer/km² to 32.7 deer/km². The percentages of debarked trees within a plot ranged from 0 to 84%. Debarking was promoted by high deer density, small tree size, and thick snow. The effect of tree size on debarking was stronger than that of deer density. Occurrence of browsing on understory vegetation was higher at higher deer densities, and where understory vegetation was dominated by evergreen dwarf bamboo. Coverage and maximum height of understory vegetation were unaffected by deer density but increased with canopy openness and the dominance of dwarf bamboo in the understory. Overall, we predict that debarking of small trees living in heavy snow areas should occur even at low deer densities (<10 deer/km²). Browsing on dwarf bamboo should occur at intermediate deer densities (10–30 deer/km²), while debarking of thick trees living in low snow areas should occur only at high deer densities (≥30 deer/km²). Our study shows that debarking and browsing on understory vegetation are appropriate indices for evaluating deer impacts on forest ecosystems, but that tree size, snow depth, and the type of understory vegetation should also be considered.     

The regeneration of pioneer tree species under browsing pressure of Sika deer in an evergreen oak forest

The effects of Sika deer (Cervus nippon) browsing on the regeneration of pioneer species were studied in relation to canopy gaps in a warm temperate evergreen oak forest in Kasugayama, Nara City. Four study sites, three in canopy gaps and one under a closed canopy, were selected and each divided into fenced and unfenced plots. Under the closed canopy, seedlings of all the pioneer species died irrespective of browsing pressure. However, in the canopy gap sites, seedlings of the pioneer species could establish and grow well. The seedling survival ratio in the fenced plots in the canopy gaps was >60% 1 year after germination. However, in the unfenced plots, only <20% of the seedlings survived 1 year, with all dying within 3 years after germination. Thus, the regeneration of pioneer trees in this forest was strongly inhibited by deer browsing. Successful regeneration of a pioneer,Zanthoxylum ailanthoides, occurred for several years even after two major wind disturbances during the past 90 years. This may be due to less browsing pressure from the deer.     

A Long-term Study of Seedling Regeneration for an Oak Forest Restoration in Cleveland Metroparks Brecksville Reservation,Ohio

The Cleveland Metroparks Brecksville Reservation initiated an oak forest restoration in 1990, using thinning and burning to encourage regeneration of oak forest species. In 96 quadrats (81 treatment and 15 control), understory woody species were inventoried from 1992 to 2002, and canopy opening was quantified. Six years into the study, the entire reservation became heavily populated with white-tailed deer (Odocoileus virginianus) and gypsy moths (Lymantria dispar), complicating the restoration efforts. During data analysis, understory woody species were classified into oak forest type and nonoak forest type, and three distinct phases became evident (phase 1: 1992–1994 treatment effects only, phase 2: 1995–1999 period of invasion by deer and gypsy moths, and phase 3: 2000–2002 post-invasion period). Both oak forest and nonoak forest species increased in the treatment area over the control area. During phase 1, burning encouraged oak seedlings, and thinning reduced competition from nonoak species, suggesting a temporarily successful restoration attempt. The intense gypsy moth browse in phase 2 reduced the number of oak seedlings, creating conditions favorable to nonoak species. The quantity and diversity of seedlings increased as gypsy moths opened the canopy. Deer browsed most species, oak and nonoak, even when deer populations decreased and more species were available. Original treatment effects may have been continuing in phase 3; however, additional years of study are needed.     

Phylogenetic Structure of Tree Species across Different Life Stages from Seedlings to Canopy Trees in a Subtropical Evergreen Broad-Leaved Forest

Investigating patterns of phylogenetic structure across different life stages of tree species in forests is crucial to understanding forest community assembly, and investigating forest gap influence on the phylogenetic structure of forest regeneration is necessary for understanding forest community assembly. Here, we examine the phylogenetic structure of tree species across life stages from seedlings to canopy trees, as well as forest gap influence on the phylogenetic structure of forest regeneration in a forest of the subtropical region in China. We investigate changes in phylogenetic relatedness (measured as NRI) of tree species from seedlings, saplings, treelets to canopy trees; we compare the phylogenetic turnover (measured as β_NRI) between canopy trees and seedlings in forest understory with that between canopy trees and seedlings in forest gaps. We found that phylogenetic relatedness generally increases from seedlings through saplings and treelets up to canopy trees, and that phylogenetic relatedness does not differ between seedlings in forest understory and those in forest gaps, but phylogenetic turnover between canopy trees and seedlings in forest understory is lower than that between canopy trees and seedlings in forest gaps. We conclude that tree species tend to be more closely related from seedling to canopy layers, and that forest gaps alter the seedling phylogenetic turnover of the studied forest. It is likely that the increasing trend of phylogenetic clustering as tree stem size increases observed in this subtropical forest is primarily driven by abiotic filtering processes, which select a set of closely related evergreen broad-leaved tree species whose regeneration has adapted to the closed canopy environments of the subtropical forest developed under the regional monsoon climate.     

格氏栲天然林林窗和林下种子散布及幼苗更新研究

以格氏栲(Castanopsis kawakamii)天然林为研究对象,探讨了林窗和林下格氏栲种子雨、种子库的分布特征及幼苗更新状况。结果表明:林窗种子雨总量和完好种子密度高于林下,未成熟种子比例低于林下;林窗和林下种子雨高峰期掉落数量分别占种子雨总量的77.13%和74.5%;林窗种子库储量低于林下,种子库中以全食或捡拾种子比例最高,其中种子库储量垂直分布表现为枯落物层(约占2/3)>腐殖质层(0～5 cm)(约占1/3)>心土层(5～10 cm)(小于1%),以格氏栲种子占绝对优势;格氏栲从种子到幼苗的转化率低,林窗中格氏栲完好种子密度与幼苗密度均高于林下。林窗微生境提高了种子散布过程中格氏栲成熟种子的密度和比例,有利于促进格氏栲的幼苗更新,表明林窗在格氏栲种群恢复过程中扮演着重要角色。     

东灵山地区辽东栎幼苗的建立和空间分布

研究树木实生苗的建立对森林生态系统的保育和恢复具有重要意义,在北京东灵山地区调查了辽东栎(Quercus liaotungensis)实生和萌生幼苗在几种典型的植被类型中的空间分布以及辽东栎一年生实生幼苗在1个林窗梯度上的建立。选择几种典型的植被类型,研究辽东栎实生幼苗和萌生幼苗在森林中的空间分布。结果显示,在不同植被类型中辽东栎实生和萌生幼苗的密度存在空间差异,实生苗密度随幼苗年龄增大逐渐降低,种群的更新主要依靠萌生苗完成。在1个落叶阔叶林中选择1个林窗,在不同梯度(即林窗中间、林窗和树冠连接处,以及树冠下)上,播种辽东栎坚果,第二年秋季调查实生幼苗的2个生长指标和出苗率。结果显示,林窗对一年生实生幼苗的生长高度有影响。幼苗高度在林窗中比在树冠下大;林窗对辽东栎幼苗最长叶片长度和幼苗的出苗率没有影响。说明辽东栎实生幼苗的良好生长需要阳光比较充足的生境条件。本项研究结果建议,对辽东栎种群的更新,应该适当择伐一些较大个体,使森林形成一些林窗或林中空地,以利于辽东栎实生幼苗的建立,这样才能使辽东栎种群通过实生苗进行更好的自然更新。     

冠层结构和光环境的时空变化对紫耳箭竹种群特征的影响

选择金佛山国家自然保护区内落叶阔叶林、常绿落叶阔叶混交林、常绿阔叶林3种典型群落类型,研究冠层结构和光环境特征,以及林下优势种--紫耳箭竹的种群特征.结果表明: 随着落叶阔叶林→常绿落叶阔叶混交林→常绿阔叶林的演替,Shannon多样性指数、Simpson优势度指数和Pielou指数呈增加趋势,表明群落趋于稳定发展的状态;冠层结构特征也发生了显著改变,冠层开度和平均叶倾角减小,叶面积指数增加,冠层的消光能力增强,林下光照水平降低.上层林冠是造成林型郁闭的主要原因,其中冠层厚度和冠层面积是2个主要的影响因素.冠层结构与林下光照指标显著相关,对林下散射光的影响最大.冠层开度、林下光照条件均随着生长季的到来而下降,而叶面积指数呈现增长的趋势,峰值出现在6、7月;平均叶倾角在春季达到最大值,在夏季为最小值.紫耳箭竹的生长与冠层结构和光环境密切相关,其在光照适中的常绿落叶阔叶混交林中生长得最好,分株粗壮、密度大(29.69±1.68株·m^-2),地下茎拓展能力强;落叶阔叶林中的强光环境可能造成土壤水分缺失,从而对其生长产生影响;而在常绿阔叶林的低光环境下紫耳箭竹分株矮小,密度小(5.80±1.16株·m^-2),克隆扩展能力降低.在森林结构演变的过程中,冠层结构发生了明显的改变,显著影响林下光环境,过度的低光环境对紫耳箭竹种群的更新和发展有限制作用.     

Herbivore-induced expansion of generalist species as a driver of homogenization in post-disturbance plant communities

We used a controlled experiment to investigate how disturbance scale (canopy gap area) and herbivory influence post-disturbance plant community dynamics. Twenty canopy gaps were installed in a temperate hemlock-hardwood forest during the winter of 2002–2003: seven small gaps (50–150 m²), seven medium gaps (151–250 m²), and six large gaps (251–450 m²). Within each gap, we established 4–12 sample plots (depending on gap size); 1–3 of which were enclosed with wire mesh white-tailed deer (Odocoileus virginianus) exclosures in 2005. Gaps were revisited and intensively sampled in 2007. After five growing seasons, ground-layer plant communities in non-exclosed plots were more similar compositionally than exclosure plots. Non-exclosed plots in small and medium gaps were more similar to non-exclosed plots in large gaps than they were to exclosed plots in their respective gap size class. Shade-tolerant forbs and trees were less common outside exclosures, while generalist species associated with higher understory light levels and exotics were more prevalent outside exclosures. Our results suggest that even in forests with relatively low deer densities (6.5–9.3 deer km⁻²), white-tailed deer herbivory may influence the developmental trajectory of post-disturbance plant communities and be a mechanism for decreasing β-diversity along environmental gradients.     

Red deer mediate spatial and temporal plant heterogeneity in boreal forests

Selective herbivory can influence both spatial and temporal vegetation heterogeneity. For example, many northern European populations of free-ranging ungulates have reached unprecedented levels, which can influence plant species turnover, long-term maintenance of biodiversity and the subsequent stability of boreal ecosystems. However, the mechanisms by which large herbivores affect spatial and temporal vegetation heterogeneity remain poorly understood. Here, we combined a 10-year exclusion experiment with a herbivore intensity gradient to investigate how red deer (Cervus elaphus) acts as a driver of temporal and spatial heterogeneity in the understory of a boreal forest. We measured the two dimensions of heterogeneity as temporal and spatial species turnover. We found that temporal heterogeneity was positively related to herbivory intensity, and we found a similar trend for spatial heterogeneity. Removing red deer (exclosure) from our study system caused a distinct shift in species composition, both spatially (slow response) and temporally (quick response). Vegetation from which red deer had been excluded for 10 years showed the highest spatial heterogeneity, suggesting that the most stable forest understory will occur where there are no large herbivores. However, excluding red deer resulted in lower species diversity and greater dominance by a low number of plant species. If both stable but species rich ecosystems are the management goal, these findings suggest that naturally fluctuating, but moderate red deer densities should be sustained.     

The interplay of plant and animal disease in a changing landscape: the role of sudden aspen decline in moderating Sin Nombre virus prevalence in natural deer mouse populations

We examined how climate-mediated forest dieback regulates zoonotic disease prevalence using the relationship between sudden aspen decline (SAD) and Sin Nombre virus (SNV) as a model system. We compared understory plant community structure, small mammal community composition, and SNV prevalence on 12 study sites within aspen forests experiencing levels of SAD ranging from <10.0% crown fade to >95.0% crown fade. Our results show that sites with the highest levels of SAD had reduced canopy cover, stand density, and basal area, and these differences were reflected by reductions in understory vegetation cover. Conversely, sites with the highest levels of SAD had greater understory standing biomass, suggesting that vegetation on these sites was highly clustered. Changes in forest and understory vegetation structure likely resulted in shifts in small mammal community composition across the SAD gradient, as we found reduced species diversity and higher densities of deer mice, the primary host for SNV, on sites with the highest levels of SAD. Sites with the highest levels of SAD also had significantly greater SNV prevalence compared to sites with lower levels of SAD, which is likely a result of their abundance of deer mice. Collectively, results of our research provide strong evidence to show SAD has considerable impacts on vegetation community structure, small mammal density and biodiversity and the prevalence of SNV.     

林窗对格氏栲天然林更新层物种生态位的影响

采用改进更新生态位宽度和更新生态位重叠模型分析林窗干扰对福建三明市格氏栲天然林更新层物种生态位的影响。结果表明:林窗中格氏栲更新生态宽度值大于林下,林窗在促进格氏栲更新过程中具有重要作用。林窗和林下更新生态位宽度最大的为桂北木姜子,其与格氏栲更新生态位重叠值也较大。林窗中的格氏栲与其它物种更新生态位重叠值低于0.6,林窗微生境的异质性导致格氏栲与其它树种间对资源的利用存在明显的共享趋势,促进了物种间共存。林下的格氏栲与木荷、木荚红豆和短尾越桔的更新生态位重叠值均高于0.6,格氏栲与这些物种相互争夺资源与空间,种间竞争较强。格氏栲天然林未来树种组成中,主要由桂北木姜子、木荷、矩圆叶鼠刺与格氏栲等组成的混交群落,整个群落正向物种组成多样化的方向演变。     

Forage availability for white-tailed deer following silvicultural treatments in hardwood forests

Closed-canopy upland hardwood stands often lack diverse understory structure and composition, limiting available nutrition for white-tailed deer (Odocoileus virginianus) as well as nesting and foraging structure for other wildlife. Various regeneration methods can positively influence understory development; however, non-commercial strategies are needed to improve available nutrition in many stands, as some contain timber that is not ready to harvest and others are owned by landowners who are not interested in harvesting timber. Applications of herbicide and prescribed fire have improved availability of food and cover for deer and other wildlife in pine (Pinus spp.) systems. However, this strategy has not been evaluated in hardwood systems. To evaluate the influence of fire and herbicide treatments on available deer forage in upland hardwood systems, we measured forage availability and calculated nutritional carrying capacity (NCC) at 14% crude protein mixed diet, following 7 silvicultural treatments, including controls, in 4 mixed upland hardwood stands July–September 2007 and 2008. We compared NCC among forest treatments and within 4 paired warm-season forage food plots to evaluate the usefulness of food plots in areas where forests are managed. Nutritional carrying capacity estimates (deer days/ha) were greatest following canopy reduction with prescribed fire treatments in both years. Understory herbicide application did not affect species composition or NCC 1 year or 2 years post-treatment. Production of forage plantings exceeded that of forest treatments both years with the exception of early-maturing soybeans and retention cut with fire 2 years post-treatment. We encourage land managers to use canopy reducing treatments and low-intensity prescribed fire to increase available nutrition and improve available cover where needed in upland hardwood systems. In areas where deer density may limit understory development, high-quality forage food plots may be used to buffer browsing while strategies to reduce deer density and stimulate the forest understory are implemented. © 2011 The Wildlife Society.     

The confounding effects of logging on tree seedling growth and herbivory in Central Amazon

Light availability is an important modulator of seedling growth and plant–herbivore dynamics. Logging increases light levels in forests, potentially altering herbivore–plant interactions that drive seedling establishment. We conducted a transplant experiment to evaluate how logging and herbivory affect seedling growth and survival in three shade‐tolerant tree species, at paired canopy gap and understory sites in logged forest and an adjacent unlogged area in central Amazonia (Brazil). Seedlings were either left exposed to naturally occurring insect herbivores or protected from insects by a fine netting structure. We measured the herbivore damage and growth rate of seedlings after 18 mo. In general, logged areas received more light than unlogged sites. Growth and herbivory rates were positively influenced by light, and herbivory was also influenced positively by logging. In gaps, increased growth mitigated foliar damage. Logging resulted in a loss of foliar tissue due to increased herbivory. Herbivory rates were higher in the understory of logged sites than in that of unlogged understory sites, but growth was similar in these areas. Thus, the understory of logged areas provided the least favorable sites for shade‐tolerant tree regeneration, due to higher herbivory rates. The effect of logging on biotic interactions can extend beyond the gaps it creates into untouched understory sites. To our knowledge, this is the first time such a pattern has been observed, highlighting the importance of evaluating the impact of logging on biotic interactions.     

Cultivation of Non‐timber Forest Products Alters Understory Light Availability in a Humid Tropical Forest in Mexico1

The planting of non‐timber forest products (NTFPs) in the understory of tropical forests is promoted in many regions as a strategy to conserve forested lands and meet the economic needs of rural communities. While the forest canopy is left intact in most understory plantations, much of the midstory and understory vegetation is removed in order to increase light availability for cultivated species. We assessed the extent to which the removal of vegetation in understory plantations of Chamaedorea hooperiana Hodel (Arecaceae) alters understory light conditions. We also examined how any changes in light availability may be reflected by changes in the composition of canopy tree seedlings regenerating in understory plantations. We employed a blocked design consisting of four C. hooperiana plantation sites; each site was paired with an adjacent, unmanaged forest site. Hemispherical canopy photographs were taken and canopy tree seedlings were identified and measured within 12 3 × 2 m randomly placed plots in each site for a total of 96 plots (4 blocks × 2 sites × 12 plots). Plantation management did not affect canopy openness or direct light availability but understory plantations had a higher frequency of plots with greater total and diffuse light availability than unmanaged forest. Comparisons of canopy tree seedling composition between understory plantations and unmanaged forest sites were less conclusive but suggest that management practices have the potential to increase the proportion of shade‐intolerant species of tree seedlings establishing in plantations. Given the importance of advanced regeneration in gap‐phase forest dynamics, these changes may have implications for future patterns of succession in the areas of forest where NTFPs are cultivated.     

辽东栎林内不同小生境下幼树植冠构型分析

以黄土高原黄龙山林区辽东栎林内3个小生境（林下、林隙、林缘）下辽东栎天然更新幼树为研究对象,采用典型抽样法对辽东栎幼树侧枝、叶片和树冠的空间分布状况以及生物量分配状况进行调查分析,探讨微生境与幼树植冠构型特征的关系,明确辽东栎幼树对不同小生境的适应策略,为栎林经营和林分结构优化提供理论依据。结果显示：（1）3种生境下辽东栎幼树构型发生了可塑性变化,林下幼树树冠层次比较单一,林隙与林缘的幼树树冠层次更加丰富。（2）由林下至林缘,幼树的树高、枝下高呈逐渐减小的趋势,而地径变化趋势与之相反;幼树的冠幅、树冠面积、树冠率呈先增加后减小的趋势,并且林下与林隙、林缘的差异显著;幼树的总体分枝率、逐步分枝率、枝径比呈先增加后减小的趋势。（3）3种生境下,幼树的一级枝的枝长、直径与倾角随着树高的增加而呈减小的趋势,但3种生境的差异不显著;林下一级枝主要分布在冠层中上部,而林隙与林缘一级枝主要分布在冠层中下、中上部。（4）由林下至林缘幼树叶长、叶宽、单叶面积和比叶面积逐渐降低,而单株叶数、叶总面积、叶面积指数呈先增大后减小趋势;与其他2种生境相比林下叶片分布趋于冠层上部。（5）幼树地上部分生物量中林下主干生物量占83%,枝和叶生物量只占17%;而林隙与林缘虽然各部位生物量有所差异但比例基本一致,其中主干占66%左右,枝和叶生物量占34%左右。研究表明,林隙生境下幼树的构型优于林缘和林下生境,在今后栎林的经营中,可以通过适当间伐来增加林隙数量,为森林更新和结构的优化提供有利条件。     

Gap regeneration and replacement patterns in an old-growth <Emphasis Type="Italic">Fagus</Emphasis>–<Emphasis Type="Italic">Abies</Emphasis> forest of Bosnia–Herzegovina

We examined the influence of small-scale gap disturbances on stand development and tree species coexistence in an old-growth Fagus sylvatica–Abies alba forest in the Dinaric Mountains of Bosnia–Herzegovina. The structure and composition of tree regeneration in gaps were compared to the forest as a whole, and the influence of gap size on the density and composition of regeneration was assessed. Transition probabilities were also calculated from gapfillers in different life stages to examine canopy replacement patterns. The structure and composition of tree regeneration were similar between gaps and the forest as a whole, and there was no relationship between overall regeneration density and gap size, indicating most individuals established prior to gap formation. Likewise, there was no strong evidence of gap-size partitioning for shade tolerant F. sylvatica and A. alba, although less tolerant Acer pseudoplatanus only recruited to taller life stages in larger gaps. Transition probabilities calculated from the seedling and sapling data suggest that most gaps will be captured by F. sylvatica, while probabilities based on pole-sized gapmakers indicate both A. alba and F. sylvatica will be maintained in the canopy. We suggest that gaps primarily play a role in reorganizing advance regeneration, and that coexistence of shade tolerant F. sylvatica and A. alba is more likely related to their differential ability to tolerate shaded understory conditions, particularly during larger life stages, rather than gap-size partitioning.     

Response of clonal plasticity of Fargesia nitida to different canopy conditions of subalpine coniferous forest

The aim of this study is to explore the effects of canopy conditions on clump and culm numbers, and the morphological plasticity and biomass distribution patterns of the dwarf bamboo species Fargesia nitida. Specifically, we investigated the effects of canopy conditions on the growth and morphological characteristics of F. nitida, and the adaptive responses of F. nitida to different canopy conditions and its ecological senses. The results indicate that forest canopy had a significant effect on the genet density and culm number per clump, while it did not affect the ramet density. Clumps tended to be few and large in gaps and forest edge plots, and small under forest understory plots. The ramets showed an even distribution under the closed canopy, and cluster distribution under gaps and forest edge plots. The forest canopy had a significant effect on both the ramets’ biomass and biomass allocation. Favourable light conditions promoted ramet growth and biomass accumulation. Greater amounts of biomass in gaps and forest edge plots were shown by the higher number of culms per clump and the diameter of these culms. Under closed canopy, the bamboos increased their branching angle, leaf biomass allocation, specific leaf area and leaf area ratio to exploit more favourable light conditions in these locations. The spacer length, specific spacer length and spacer branching angles all showed significant differences between gaps and closed canopy conditions. The larger specific spacer length and spacer branching angle were beneficial for bamboo growth, scattering the ramets and exploiting more favourable light conditions. In summary, this study shows that to varying degrees, F. nitida exhibits both a wide ecological amplitude and high degree of morphological plasticity in response to differing forest canopy conditions. Moreover, the changes in plasticity enable the plants to optimize their light usage efficiency to promote growth and increase access to resources available in heterogeneous light environments. __________ Translated from Acta Ecologica Sinica, 2006, 26(12): 4019–4026 [译自: 生态学报]