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1.
生境斑块化对食果鸟类的移动行为产生影响,进而影响其对植物种子的传播格局和效率。南方红豆杉(Taxus chinensis var.mairei)是我国一级保护植物,在南方山区多因人为干扰而呈斑块状分布。2011年,2012年10月底到12月中,以分布于福建梅花山国家级自然保护区红豆杉生态园中南方红豆杉种群为对象,研究斑块生境中鸟类对南方红豆杉种子的取食和传播行为,并评估专性鸟类和泛性鸟类的传播效率。结果发现:南方红豆杉源斑块共吸引22种食果鸟类取食红豆杉种子,并与13种鸟类形成了种子传播关系。不同年间,黑短脚鹎(Hypsipetes leucocephalus)都是植物的主要传播鸟类,而其他鸟类传播者种类具有一定的年间变化。生境斑块化导致专性鸟类黑短脚鹎和泛性鸟类红嘴蓝鹊(Urocissa erythrorhyncha)种子传播效率差异。与红嘴蓝鹊相比,黑短脚鹎飞行的平均距离较短((16.3±11.0)m,Mean±SD,n=125),传播距离相对较近;且它们取食后偏好在源斑块中活动,喜栖息在同种成树、甜楮(Castanopsis eyrei)及其他阔叶树等栖树上。红嘴蓝鹊取食后常在斑块间移动,常停歇在同种成树和毛竹(Phyllostachys heterocycla)上,传播距离相对较远((24.9±20.0)m,Mean±SD,n=95)。空间一致性结果表明,黑短脚鹎移动距离对幼苗更新距离的空间一致性程度高;而红嘴蓝鹊偏好生境与幼苗更新生境一致性程度高。结果表明,斑块生境中植物能与专性鸟类、泛性鸟类之间形成种子传播互惠关系,且种子传播效率受到专性鸟类和泛性鸟类传播距离和传播生境的影响。  相似文献   

2.
张帅  范月峥  王征 《生态学杂志》2020,(8):2657-2662
在破碎化生境斑块中,植物特征影响着鸟类多样性格局,进而影响斑块的生态功能维系。南方红豆杉(Taxus chinensis)为国家Ⅰ级保护植物,在我国南方地区多集群分布在破碎化生境斑块中。为了解斑块生境中南方红豆杉母树特征对访问鸟类多样性的影响,于2018和2019年果期在福建梅花山保护区红豆杉生态园采用样线法和样点法结合,研究南方红豆杉结实量、郁闭度和高度等特征对访问鸟类多样性的影响。结果表明:在红豆杉生态园中,共有67种鸟类,其中45种鸟类为食果鸟类。不同年份间和不同斑块(竹林斑块和常绿阔叶林斑块)的鸟类群落组成和优势鸟类存在一定的差异。共有21种鸟类访问南方红豆杉母树,其多样性特点受母树特征的影响。一元线性回归模型表明,南方红豆杉母树结实量与访问母树的鸟类数量和种数呈正相关;母树郁闭度与访问母树的鸟类数量呈正相关。可见,斑块生境中南方红豆杉母树特征是影响鸟类多样性的主要因素之一,进而影响植物的种子更新。  相似文献   

3.
食果动物与依赖其传播种子的植物间在进化过程中形成互惠关系,生境破碎化往往干扰种子传播过程,继而破坏这种关系.生境破碎化通常降低食果动物的多样性,但亦有相反的情况出现.食果动物对生境破碎化的适应能力不同,泛性森林动物和广食性动物具有较强的适应性.生境破碎化对依赖动物传播的植物影响有差异,多数植物受到负面影响,但也有一些植物不受影响,甚至受益.动物在破碎生境中对种子传播的有效性是种子搬运量、传播距离、种子萌发及种群建立等环节的综合效果.破碎化生境中种子的搬运量与动物的觅食行为和食物选择有关;种子传播距离受食物资源可获得性的改变和生境斑块异质性的影响;种子萌发和更新种群建立成功与否决定于是否存在有效的种子传播者.生境破碎化如何影响种子传播以及动植物相互关系,尤其是异质斑块的空间分布如何影响食果动物的传播有效性、破碎化生境下动植物互惠共生关系如何建立,生境破碎化导致的植物入侵对本地植物种子传播的影响是未来需要深入研究的问题.  相似文献   

4.
食果鸟类在红豆杉天然种群形成中的作用   总被引:4,自引:2,他引:2  
朱琼琼  鲁长虎 《生态学杂志》2007,26(8):1238-1243
2005年10月初至2006年2月,在南京中山植物园研究了红豆杉(Taxus chinensis)天然更新种群的分布格局,野外定点观察了鸟类对红豆杉种子的取食行为,记录了红豆杉落果的命运,分析了食果鸟类在红豆杉种群形成中的作用。结果表明:红豆杉天然更新种群集中分布于距母树群10m以外面积约0.5hm2的山坡上,全部红豆杉幼苗、幼树共213株,主要分布在中下坡;幼苗和幼树的空间水平格局符合聚集分布特征。"果实"成熟后,一部分被鸟类直接在树上取食,一部分掉落母树下地面。经过对结实母树的定点、连续观察,记录到4种鸟类取食红豆杉"果实",其中红嘴蓝鹊(Urocissa erythrorhyncha)和白头鹎(Pyc-nonotus sinensis)为主要的取食者和传播者。食果鸟类整吞"果实",消化果肉(假种皮)后,种子经消化道随粪便排出,以此过程传播种子。在取食完红豆杉"果实"后,食果鸟类多飞向坡上。坡上排水良好,有适量的荫蔽,生境适宜红豆杉种子萌发和幼苗的成长。因此,食果鸟类将种子传播至适宜萌发和生长的环境中,对该红豆杉种群的天然更新起主要作用。同时,鸟类传播对于红豆杉种群扩散、占据新的生境也有着特殊的意义。  相似文献   

5.
肉质果植物通常依赖食果鸟类等取食果实后经消化道过程传播种子, 以完成种群的更新。红楠(Machilus thunbergii)是亚热带森林的代表性种类, 其果实具有依赖鸟类等动物取食后传播的特点。2012 年、2013 年在梅花山国家级自然保护区,研究了鸟类对红楠果实的取食及种子的传播作用。结果如下: 取食红楠种实的鸟类共计18 种, 其中整吞果实的鸟类12 种,啄取果肉的鸟类5 种, 啄食种子的鸟类1 种。整吞果实鸟类中4 种鹎科和2 种鸦科鸟类访问频次和取食量较大, 是主要的种子传播者。鸟类主要以呕吐方式传播种子。取食后初停栖点与母树距离及地面种子散布地点的分析结果表明, 鸟类可以远距离扩散种子。地面种实可被啮齿动物或蚁类再次捕食或搬运。研究表明, 红楠可以借助鸟类实现种子传播和种群更新。  相似文献   

6.
传播有效性是评估食果动物对植物种群更新贡献的关键指标,它决定了植物种群的续存,影响着群落生物多样性的维系。本文从种子传播数量、质量角度分析了影响动物传播有效性的因素,并从有效传播动物组合角度分析了其对植物种群更新的影响。传播数量的多少与动物的取食行为有关。以整吞取食的食果动物常被认为是植物的有效传播动物,而植物的果实为动物偏好选择的食物时,势必导致该种植物拥有高的种子传播数量。传播质量与食果动物肠道种子滞留时间以及其后的种子传播距离和排放地相关。体型较大、生境适应能力和迁徙性较强的动物常为植物提供较远的传播距离,而被认为传播质量较高。取食后动物的生境选择决定了种子的排放地,进而影响它们的种子传播质量。如果取食后动物偏好利用植物适宜更新的生境时,动物则拥有较高的传播质量。有效传播动物通常在传播数量和传播质量以互补形成一些组合对植物种群更新起贡献。今后工作应将动物行为野外监测和种子萌发实验相结合、取食后多种行为相结合来分析动物的传播有效性;而以一些国内特有濒危植物为研究对象开展传播有效性研究应是今后恢复生态学研究的重点。  相似文献   

7.
2010年9月至2013年4月通过设置人工土壤种子库,研究了野生樱桃李土壤种子库的动态及啮齿动物和凋落物覆盖对种子库中种子命运的影响.结果表明: 在有取食动物扰动下,48.3%的种子萌发输出为幼苗,50%的种子被动物搬运或当场取食,4%的种子腐烂.在排除了取食动物干扰的条件下,樱桃李种子形成了短期持久的土壤种子库,3年后依然有部分种子萌发并输出为幼苗.凋落物覆盖和对照处理中,被搬运和当场取食种子的比例均显著低于清除凋落物的裸地.地表凋落物存留能减少动物搬运、取食,但不足以导致新生幼苗的大量出现,而啮齿类动物的搬运或取食是影响野生樱桃李种子命运和种子库动态的主要因素.
  相似文献   

8.
为明确东北红豆杉野生种群维持的关键制约因素,制定现有种群的保护策略与技术环节,本研究调查了我国主要分布区内东北红豆杉野生种群的更新状况与分布格局,分析了林分因子与人为干扰对种群更新与维持的影响。结果表明:目前我国东北红豆杉野生种群整体更新情况较差,更新个体的径级与高度级结构呈现出不健康的状态,但有19%区域更新较好,种群整体表现为成树少更新差、成树多更新差、成树少但更新较好3种类型。东北红豆杉所在群落可以划分为臭冷杉+紫椴林、杂木林、兴安鱼鳞云杉+臭冷杉林,其中臭冷杉+紫椴林的更新数量显著多于杂木林;林分密度增加与适度的人为干扰对东北红豆杉更新有一定的促进作用,林分由低密度增到中等密度时东北红豆杉更新幼苗数量显著增加,所在生境受到适度干扰的种群更新数量显著多于轻度干扰下的种群。人为干扰和栖息地生境是目前东北红豆杉野生种群维持与更新的关键制约因素。东北红豆杉的保护应基于各生境斑块种群的更新现状制定相应的就地保护和回归保护等措施,并在保护过程中重点考虑干扰和生境条件等关键因素的影响。  相似文献   

9.
梁振玲  马建章  戎可 《生态学报》2016,36(4):1162-1169
分散贮食是许多动物取食行为策略的重要组成部分。对以植物种子为主要贮食对象的动物来说,种子内营养物质含量、种子大小以及种子内次生化合物的含量等因素都直接影响动物的贮食行为。动物偏爱贮藏个体较大的种子,大种子多被搬运并分散贮藏在远离种源的地方,而小种子则多被就地取食,以补充动物贮食过程中的能量消耗。贮食动物主要通过空间记忆、特殊路线以及贮藏点周围的直接线索等途径重新获取贮藏点内食物。在重取过程中,一些贮藏点被遗忘,其中的种子成为植物种群更新的潜在种子库。因此,分散贮食动物不仅是种子捕食者,还是种子传播者,它们对植物种子的捕食、搬运和贮藏,影响了植物种子的存活和幼苗的建成,从而在一定程度上影响植物种群的更新、分布。植物种群为了促进种子的传播,在进化过程中逐渐形成了形式多样的适应性策略,降低种子的直接被捕食率,提高种子的被贮藏率。研究动物分散贮食行为对植物种群更新的影响,将有助于理解贮食动物与植物之间的互惠关系,从而认识贮食动物种群在生态系统中的作用,为生物多样性的保护提供科学依据。  相似文献   

10.
南方红豆杉的天然更新格局及食果鸟类对其种子的传播   总被引:2,自引:0,他引:2  
2006年9-12月,在皖南仙寓山对南方红豆杉(Taxus chinensis var.mairei)天然更新种群的分布格局及食果鸟类对其种子的传播作用进行了研究.结果表明:天然更新种群集中分布于仙寓山海拔540 m以上面积约1.1 hm2的山坡上,与毛竹混生.共统计红豆杉1 331株,其中高度30 cm以下的幼苗1 167株,占总数的87.68%.该红豆杉种群为缓慢增长型种群,空间水平格局呈聚集分布.经过对结实母树的定点连续观察,记录到10种鸟类取食红豆杉种子,其中红嘴蓝鹊(Urocissa erythrorhyncha)、栗背短脚鹎(Hemixos castanonotus)和绿翅短脚鹎(Hypsipetes mcclellandii)为主要的取食者和传播者.食果鸟类吞入种子后,消化果肉(假种皮)后,种子随粪便排出而得以传播.野外调查中,在鸟类经常活动的地点发现带有红豆杉种子新鲜的鸟类粪便,每个含有1~2颗种子.未被鸟类取食的落果自然掉落于树冠下,假种皮被昆虫取食或腐烂,种子在母树下能正常萌发,但存活率几乎为零.因此,鸟类在该红豆杉天然种群形成中起到了重要作用,它们将种子传播至适宜萌发和生长的环境中.  相似文献   

11.
Tree seed retention is thought to be an important factor in the process of forest community regeneration. Although dense understory dwarf bamboo has been considered to have serious negative effects on the regeneration of forest community species, little attention has been paid to the relationship between dwarf bamboo and seed retention. In a field experiment we manipulated the density of Fargesia decurvata, a common understory dwarf bamboo, to investigate the retention of seeds from five canopy tree species in an evergreen and deciduous broad-leaved mixed forest in Jinfoshan National Nature Reserve, SW China. We found that the median survival time and retention ratio of seeds increased with the increase in bamboo density. Fauna discriminately altered seed retention in bamboo groves of different densities. Arthropods reduced seed survival the most, and seeds removed decreased with increasing bamboo density. Birds removed or ate more seeds in groves of medium bamboo density and consumed fewer seeds in dense or sparse bamboo habitats. Rodents removed a greater number of large and highly profitable seeds in dense bamboo groves but more small and thin-husked seeds in sparse bamboo groves. Seed characteristics, including seed size, seed mass and seed profitability, were important factors affecting seed retention. The results suggested that dense understory dwarf bamboo not only increased seeds concealment and reduced the probability and speed of seed removal but also influenced the trade-off between predation and risk of animal predatory strategies, thereby impacting the quantity and composition of surviving seeds. Our results also indicated that dense understory dwarf bamboo and various seed characteristics can provide good opportunities for seed storage and seed germination and has a potential positive effect on canopy tree regeneration.  相似文献   

12.
Post‐dispersal predation can be a major source of seed loss in temperate forests. Little is known, however, about how predator‐mediated indirect interactions such as apparent competition alter survival patterns of canopy tree seeds. Understorey plants may enhance tree seed predation by providing sheltered habitat to granivores (non‐trophic pathway). In addition, occurrence of different tree seeds in mixed patches may lead to short‐term apparent competition between seed types, because of the granivores’ foraging response to changes in food patch quality (trophic pathway). We hypothesised that understorey bamboo cover and mixing of seed species in food patches would both increase tree seed predation in a Nothofagus dombeyi?Austrocedrus chilensis forest in northern Patagonia, Argentina. Seed removal experiments were conducted for three consecutive years (2000–2002) differing in overall granivory rates. Seed patch encounter and seed removal rates were consistently higher for the larger and more nutritious Austrocedrus seeds than for the smaller Nothofagus seeds. Seed removal was greater beneath bamboo than in open areas. This apparent competition pathway was stronger in a low‐predation year (2000) than in high‐predation years (2001–2002), suggesting a shift in microhabitat use by rodents. Patch composition had a significant, though weaker, impact on seed survival across study years, whereas seed density per patch enhanced encounter rates but did not influence seed removal. Removal of the less‐preferred Nothofagus seeds increased in the presence of Austrocedrus seeds, but the reciprocal indirect effect was not observed. However, this non‐reciprocal apparent competition between seed species was only significant in the high‐predation years. Our study shows that granivore‐mediated indirect effects can arise through different interaction pathways, affecting seed survival patterns according to the predator's preference for alternative seed types. Moreover, results indicate that the occurrence and relative strength of trophic vs non‐trophic pathways of apparent competition may change under contrasting predation scenarios.  相似文献   

13.
Studies of post-dispersal seed removal in the Neotropics have rarely examined the magnitude of seed removal by different types of granivores. The relative impact of invertebrates, small rodents, and birds on seed removal was investigated in a 2,178 ha Atlantic forest fragment in southeastern Brazil. We used popcorn kernels (Zea mays—Poaceae) to investigate seed removal in a series of selective exclosure treatments in a replicated, paired design experiment that included forest understory, gaps, and forest edge sites. We recorded the vegetation around the experimental seed stations in detail in order to evaluate the influence of microhabitat traits on seed removal. Vertebrate granivores (rodents and birds) were surveyed to determine whether granivore abundance was correlated with seed removal levels. Seed removal varied spatially and in unpredictable ways at the study site. Seed encounter and seed use varied with treatments, but not with habitat type. However, seed removal by invertebrates was negatively correlated with gap-related traits, which suggested an avoidance of large gaps by granivorous ants. The abundance of small mammals was remarkably low, but granivorous birds (tinamous and doves) were abundant at the study site. Birds were the main seed consumers in open treatments, but there was no correlation between local granivorous bird abundance and seed removal. These results emphasize the stochastic spatial pattern of seed removal, and, contrary to previous studies, highlight the importance of birds as seed predators in forest habitats.  相似文献   

14.
《Acta Oecologica》2008,33(3):328-336
Studies of post-dispersal seed removal in the Neotropics have rarely examined the magnitude of seed removal by different types of granivores. The relative impact of invertebrates, small rodents, and birds on seed removal was investigated in a 2,178 ha Atlantic forest fragment in southeastern Brazil. We used popcorn kernels (Zea mays—Poaceae) to investigate seed removal in a series of selective exclosure treatments in a replicated, paired design experiment that included forest understory, gaps, and forest edge sites. We recorded the vegetation around the experimental seed stations in detail in order to evaluate the influence of microhabitat traits on seed removal. Vertebrate granivores (rodents and birds) were surveyed to determine whether granivore abundance was correlated with seed removal levels. Seed removal varied spatially and in unpredictable ways at the study site. Seed encounter and seed use varied with treatments, but not with habitat type. However, seed removal by invertebrates was negatively correlated with gap-related traits, which suggested an avoidance of large gaps by granivorous ants. The abundance of small mammals was remarkably low, but granivorous birds (tinamous and doves) were abundant at the study site. Birds were the main seed consumers in open treatments, but there was no correlation between local granivorous bird abundance and seed removal. These results emphasize the stochastic spatial pattern of seed removal, and, contrary to previous studies, highlight the importance of birds as seed predators in forest habitats.  相似文献   

15.
卧龙自然保护区亚高山暗针叶林树种更新研究   总被引:3,自引:0,他引:3  
在卧龙亚高山暗针叶林中选取有代表性的18个林窗斑块以及对照的林下样方进行群落学调查,记录乔木树种和灌木树种的相关数量特征。按照树种在林窗内外的重要值差异结合树种本身生态学特性将群落中出现的乔木层树种划分为先锋组和耐荫组两类生态种组。林窗内外乔木树种的组成明显不同,两类生态种组树种幼苗在林窗与林下环境中的更新表现出差别,这与树种本身的生态学特性以及所处林窗的环境有关,同时亚高山暗针叶林中灌木层优势种小径竹的生长对树种更新方式也产生一定的影响。  相似文献   

16.
Experimental studies of seed predation in old-fields   总被引:6,自引:0,他引:6  
Summary In a pair of experiments conducted in old-field habitats in southwestern Michigan (USA), we examined rates of seed loss to post-dispersal predators (ants and rodents). Seeds from 4–6 species of biennial plants were tested over a range of seed densities and habitat types. We found that seed removal was significantly higher in vegetated habitats than in areas of disturbed soil (both simulated small-animal diggings and a plowed field). In the undisturbed vegetation, seed losses ranged from 1–20% of seeds removed/day.An exclosure experiment demonstrated that ants and rodents foraged selectively for seeds of the six plant species tested. Rodents (Peromyscus maniculatus) fed preferentially on species producing large seeds (predominantly Tragopogon dubius). Ants (Myrmica lobicornus) foraged on smaller seeds, although their foraging preferences were not based strictly on seed size.Seed density had only a minor effect on predation rate over the range of densities tested. Predators, instead appeared to treat each experimental group of seeds as a single prey patch. Consequently, predation intensity was quite variable over distances of <20 m within a relatively homogeneous section of habitat.These field experiments provide initial estimates of seed losses to post-dispersal predators in old-field habitats. Rates of seed loss were generally less than those reported from desert or semi-arid habitats. However, for some old-field species, seed losses averaged an appreciable 10–20% day. The selective nature of the seed predators, plusthe relative patchiness of predation intensity in space, suggest that postdispersal seed predation can play a role in determining the distribution and/or abundance of old-field herbs.  相似文献   

17.
亚热带林区啮齿动物对樱桃种子捕食和搬运的作用格局   总被引:2,自引:2,他引:0  
在都江堰林区,通过在原生林、次生林和灌丛3类生境释放野生和栽培樱桃(Cerasus pseudocerasus)的种子,研究了啮齿动物对樱桃种子的捕食及其对樱桃种群更新的作用。结果表明,啮齿动物对樱桃两类种子的搬运无显著差异,而啮齿动物对野生樱桃种子的收获则明显快于栽培樱桃种子,且在3类生境均有类似的趋势。这说明啮齿动物偏爱于收获具有较高收益(种仁重/种子重)的野生樱桃种子。啮齿动物在小于10 d的时间尺度收获了所有释放的樱桃种子,其中,70%以上为啮齿动物所搬运。春季食物的匮乏可能是导致啮齿动物对樱桃种子有较大捕食压力的主要原因,而生境类型间的差异较小。因此,啮齿动物是都江堰林区樱桃地表种子的主要捕食者,它们对野生樱桃种子的选择性捕食和搬运能影响樱桃种子/果实的进化及其种群更新。  相似文献   

18.
Evidence for secondary seed dispersal by rodents in Panama   总被引:9,自引:0,他引:9  
Summary The data presented show thatVirola nobilis (Myristicaceae), a bird/mammal-dispersed tree species in Panama, may also be dispersed by a terrestrial rodent, the agouti (Dasyprocta punctata). Using a thread-marking method, we observed that agoutis scatterhoardedV. nobilis seeds that they found both singly or in clumps. Seed removal and seed burial rates were strongly affected by features of forest habitats, such asV. nobilis tree richness (rich vs poor) and/or forest age (old vs young), but not by seed dispersal treatment (scattered vs clumped). Predation (mostly post-dispersal) of unburied seeds by weevils was independent of habitat and dispersal treatment. Seeds artificially buried in aVirola-rich area were more likely to escape predation and become established than unburied seeds under natural conditions. The food reward for agoutis is in the germinating seedlings. The seed dispersal syndrome ofV. nobilis involves long- and short-distance dispersers which both appear important for tree recruitment.  相似文献   

19.
The effect of forest disturbance on survival and secondary dispersal of an artificial seed shadow (N= 800) was studied at Brownsberg Natural Park, Suriname, South America. We scattered single seeds of the frugivore‐dispersed tree Virola kwatae (Myristicaceae), simulating loose dispersal by frugivores, in undisturbed and disturbed secondary forest habitats. Seed survival rate aboveground was high (69%) within 2 wk and was negatively correlated with scatterhoarding rate by rodents, the latter being significantly lower in the undisturbed forest (9%) than in the disturbed forest (20%). Postdispersal seed predation by vertebrates was low (3%) and infestation of seeds by invertebrates was almost zero in all instances. Therefore, secondary seed dispersal by rodents in forest is not as critical for recruitment as observed among other bruchid‐infested large‐seeded species. Secondary seed dispersal by rodents may, however, facilitate seedling recruitment whether cached seeds experience greater survival than seeds remaining above ground surface.  相似文献   

20.
Mortality factors that act sequentially through the demographic transitions from seed to sapling may have critical effects on recruitment success. Understanding how habitat heterogeneity influences the causal factors that limit propagule establishment in natural populations is central to assess these demographic bottlenecks and their consequences. Bamboos often influence forest structure and dynamics and are a major factor in generating landscape complexity and habitat heterogeneity in tropical forests. To understand how patch heterogeneity influences plant recruitment we studied critical establishment stages during early recruitment of Euterpe edulis, Sloanea guianensis and Virola bicuhyba in bamboo and non-bamboo stands in the Brazilian Atlantic forest. We combined observational studies of seed rain and seedling emergence with seed addition experiments to evaluate the transition probabilities among regeneration stages within bamboo and non-bamboo stands. The relative importance of each mortality factor was evaluated by determining how the loss of propagules affected stage-specific recruitment success. Our results revealed that the seed addition treatment significantly increased seedling survivorship for all three species. E. edulis seedling survival probability increased in the addition treatment in the two stand types. However, for S. guianensis and V. bicuhyba this effect depended strongly on artificially protecting the seeds, as both species experienced increased seed and seedling losses due to post-dispersal seed predators and herbivores. Propagules of all three species had a greater probability of reaching subsequent recruitment stages when protected. The recruitment of large-seeded V. bicuhyba and E. edulis appears to be much more limited by post-dispersal factors than by dispersal limitation, whereas the small-seeded S. guianensis showed an even stronger effect of post-dispersal factors causing recruitment collapse in some situations. We demonstrated that E. edulis, S. guianensis and V. bicuhyba are especially susceptible to predation during early compared with later establishment stages and this early stage mortality can be more crucial than stand differences as determinants of successful regeneration. Among-species differences in the relative importance of dispersal vs. establishment limitation are mediated by variability in species responses to patch heterogeneity. Thus, bamboo effects on the early recruitment of non-bamboo species are patchy and species-specific, with successional bamboo patches exerting a far-reaching influence on the heterogeneity of plant species composition and abundance.  相似文献   

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