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1.
研究了 3种来自中国北方林下、草地和碱化草甸匍匐茎型克隆草本植物绢毛匍匐委陵菜 (PotentillareptansL .var.sericophyllaFranch .)、鹅绒委陵菜 (P .anserinaL .)和金戴戴 (Halerpestesruthenica (Jacq .)Qvcz .)对由高光照低养分斑块和低光照高养分斑块组成的资源交互斑块性生境的适应性对策。当生长于高光照低养分条件下分株(HL分株 )与生长于低光照高养分条件下分株 (LH分株 )之间的匍匐茎连接时 ,3种克隆植物HL分株、LH分株以及整个分株对系统 (HL分株 LH分株 )的生物量均得到显著提高。同时 ,LH分株根冠比显著增加 ,而HL分株根冠比显著下降。这表明 ,当互连分株置于由低光照高养分斑块和高光照低养分斑块组成的异质性环境中时 ,3种植物克隆分株均发生了环境诱导的功能特化。克隆内资源共享以及克隆内不同分株的功能特化有利于整个分株系统对局部丰富资源的获取 ,从而能够缓解资源交互斑块性生境对克隆植物的不利影响  相似文献   

2.
研究了3种来自中国北方林下、草地和碱化草甸匍匐茎型克隆草本植物绢毛匍匐委陵菜(Potentilla reptans L.var.sericophylla Franch.)、鹅绒委陵菜(P.anserina L.)和金戴戴(Halerpestes ruthenica (Jacq.)Qvcz.)对由高光照低养分斑块和低光照高养分斑块组成的资源交互斑块性生境的适应性对策。当生长于高照低养分条件下分株(HL分株)与生长于低光照高养分条件下分株(LH分株)之间的匍匐茎连接时,3种克隆植物HL分株、LH分株以及整个分株对系统(HL分株+LH分株)的生物量均得到显提高,同时,HL分株根冠比显增加,而HL分株根冠比显下降。这表明,当互连分株置于由低光照高养分斑块和高光照低养分斑块组成的异质性环境中时,3种植物克隆分株均发生了环境诱导的功能特化。克隆内资源共享以及克隆内不同分株的功能特化有利于整个分株系统对局部丰富资源的获取,从而能够缓解资源交互斑块性生境对克隆植物的不利影响。  相似文献   

3.
陈劲松  董鸣  于丹  刘庆 《生态学报》2004,24(5):920-924
以青藏高原和四川盆地过渡带两种不同分枝型匍匐茎植物野草莓 (Fragaria vesca)和过路黄 (Lysimachia christinae)为对象 ,研究它们在高光照低养分斑块和低光照高养分斑块组成的资源交互斑块性生境中的克隆内分工。结果显示 ,与资源的空间同质性处理 (I)和 (II)相比 ,资源的空间异质性处理 (III)和 (IV)中野草莓和过落黄的近端、远端和整个克隆片段的生物量和分株数均获得显著增加。生长在低光高养条件下的远端分株 ,若与高光低养的近端分株相连 ,相比连接到低光高养的近端分株 ,它们分配更多的生物量到地下部分 ;生长在高光低养条件下的远端分株 ,若与低光高养的近端分株相连 ,相比连接到高光低养的近端分株 ,它们分配更多的生物量到地上部分 ;生长在高光低养条件下的近端分株 ,若与低光高养的远端分株相连 ,相比连接到高光低养的远端分株 ,它们分配更多的生物量到地上部分。实验结果表明 ,资源交互斑块性生境中野草莓和过路黄均发生了克隆内分工。通过克隆内分工 ,克隆植物能有效的利用异质性分布的资源 ,缓解资源交互斑块性分布对克隆植物生长的不利影响  相似文献   

4.
匍匐茎草本绢毛匍匐委陵菜对局部遮荫的克隆可塑性   总被引:1,自引:0,他引:1  
采自林窗和林内生境的绢毛匍匐委陵菜 (PotentillareptansL .var.sericophyllaFranch)“分株对”(即由一匍匐茎节间相连着的两个分株 ,其一为“目标分株” ,另一为“相连分株”)在一户外实验中经历了全不遮荫、全部遮荫和局部遮荫处理。该植物的基株生物量、匍匐茎总长度、分株数、匍匐茎比节间重、叶柄长、比叶柄重在遮荫条件下较小。匍匐茎节间长度没有对遮荫处理发生反应。在局部遮荫处理 ,遮荫斑块的分株的叶柄长度由于连着未遮荫斑块中分株而变得更长。这种克隆整合对克隆形态可塑性的修饰作用只在林窗生境来源的实验植物中观察到。其他克隆生长和克隆形态特征的可塑性在不同生境来源的实验植物间没有差异。  相似文献   

5.
陈劲松  刘鹏  刘庆 《生态学报》2009,29(7):3532
在青藏高原和四川盆地过渡带,分别于618m和1800m两个海拔高度上研究匍匐茎克隆植物过路黄(Lysimachia christinae)在资源交互斑块性生境中的克隆内资源共享及其对生长的影响.结果显示, 在海拔1800m处,与资源的空间同质性处理(Ⅰ) 和(Ⅱ)相比, 资源的空间异质性处理(Ⅲ)和(Ⅳ)下过路黄整个克隆片段的生物量和分株数均获得显著增加;在海拔618m处,与资源的空间同质性处理(Ⅰ) 和(Ⅱ)相比,资源的空间异质性处理(Ⅲ)和(Ⅳ)下过路黄整个克隆片段生物量显著增加.在海拔618m和1800m处,生长在低光高养条件下的远端分株, 若与高光低养的近端分株相连, 相比连接到低光高养的近端分株, 它们分配更多的生物量到地下部分;在海拔1800m处,生长在高光低养条件下的远端分株, 若与低光高养的近端分株相连, 相比连接到高光低养的近端分株, 它们分配更多的生物量到地上部分.在海拔618m和1800m处,生长在高光低养条件下的近端分株, 若与低光高养的远端分株相连, 相比连接到高光低养的远端分株, 它们分配更多的生物量到地上部分.处于资源交互斑块性生境中的过路黄发生了克隆内分工,依靠相连分株间的功能分化, 克隆植物能有效的利用异质性分布的资源, 缓解资源交互斑块性分布对克隆植物生长的不利影响.通过间隔子(匍匐茎或根状茎),相连分株间能够相互传递和共享由不同分株获得的资源,这种资源共享能够提高克隆植物在异质性生境中的存活与生长.同时,方差分析显示环境异质性和海拔的交互作用显著影响克隆片段的生物量和分株数.相比于海拔618m,在海拔1800m处克隆内资源共享对克隆植物生长表现的影响更大.  相似文献   

6.
 相互连接的克隆植物分株分别处于资源互补性的不同斑块时, 将可能发生形态结构的特化, 以更有效地吸收利用所处斑块中丰富的资源, 形成分株的功能分化, 即克隆内分工。生境的斑块对比度, 作为资源或环境异质性的主要素, 在一定程度上决定克隆内分工的发生状况。该文以鹅绒委陵菜(Potentilla anserina)为材料, 在自然条件下将多组分株对置于不同的斑块对比度处理下, 比较了它们克隆内分工的发生状态, 试图发现分工与斑块对比度的关系, 同时考察在克隆分工过程中分株的可塑性变化及其与分工的关系。该实验的理论假设是: 分株发生分工的程度与分株所处斑块的资源对比度成正相关。研究结果表明, 鹅绒委陵菜分株的高度和叶面积对局部光照环境产生强烈的可塑性反应, 反应的结果是增加了对匮乏的光资源的获取。从分株根冠比和我们提出的分工指数来看, 分工的程度在一定的斑块对比度范围内随斑块对比度的增强而增强, 但到达一个最大值后又迅速降低。鹅绒委陵菜分株之间的分工和结构特化往往滞后于分株对所处局部环境的适应性可塑性变化, 而后者往往在分株之间具有独立性和局部特征。克隆内分工主要依赖于生物量分配的调节而实现, 其发生状态都是分株系统在分工收益、分工代价与分工风险之间权衡的结果, 而这种结果在很大程度上取决于分株所处的斑块对比度。  相似文献   

7.
环境资源的异质性在自然界中普遍存在。克隆植物能通过克隆整合较好地适应异质性生境。本文以海南外来强入侵性植物薇甘菊为材料,通过温室盆栽试验,研究克隆整合对异质性土壤养分生境下薇甘菊克隆片段生长的影响。结果表明:在养分异质下,克隆整合显著提高了低养分斑块分株的生物量,但同时降低了高养分斑块分株的生物量,对克隆片段总体的生长无显著影响,且这一结果不受资源输送方向的影响。克隆整合对薇甘菊克隆分株的光合速率和比叶面积影响较小,但当近端分株处于高养分条件时,其改变了克隆分株的根冠比。这些结果指示:克隆整合有利于异质性土壤养分条件下薇甘菊对低养分斑块的占领。因此,克隆整合可影响薇甘菊对资源异质性生境的入侵能力,它使薇甘菊能够扩展到低养分斑块,从而提高其入侵扩散能力。  相似文献   

8.
在深度遮光(光照强度为高光条件的6.25%,约为自然光照的5.3%)或低养分条件下,金戴戴(Halerpestes ruthenica Ovcz.)生物量、初级分株叶面积、分株总数、匍匐茎总数和总长度均显著减小,而比节间长和比叶柄长显著增加.在低养分条件下,金戴戴匍匐茎平均节间长显著增加,而匍匐茎分枝强度和分株数显著减小.这些结果与克隆植物觅食模型相符合,表明当生长于异质性生境中,金戴戴可能通过以克隆生长和克隆形态的可塑性实现的觅养行为来增加对养分资源的摄取.在深度遮光条件下,金戴戴平均间隔子长度(即平均节间长和平均叶柄长)均显著减小.这一结果与以往实验中匍匐茎草本间隔子对中度和轻度遮光(光照强度为高光条件的13%~75%,>10%的自然光照)的反应不同.这表明,在深度遮光条件下匍匐茎克隆植物可能不发生通过间隔子可塑性实现的觅光行为.光照强度和基质养分条件的交互作用对许多性状如总生物量、匍匐茎总数和总长度、二级和三级分株数、分株总数、初级分株叶面积以及分枝强度均有十分显著的效应.在高光条件下,基质养分对这些性状有十分显著的影响;而在低光条件下,基质养分条件对这些性状不产生影响或影响较小.这表明,光照强度影响金戴戴对基质养分的可塑性反应.在深度遮光或低养分条件下,金戴戴可能通过减小匍匐茎节间粗度(增加比节间长)来增加或维持其相对长度,从而更有机会逃离资源丰度低的斑块.  相似文献   

9.
薇甘菊(Mikania micrantha)原产中、南美洲,1919年薇甘菊作为杂草在中国香港出现,目前已广泛侵入中国广东、海南、云南等省区,是世界上最有害的100种外来入侵物种之一。本文以海南重要外来入侵植物薇甘菊(Mikania micrantha)为实验材料,通过温室盆栽实验,研究了克隆整合对异质性光照生境下薇甘菊克隆片段生长的影响。结果表明:在异质性光照下,克隆整合显著提高了低光斑块分株的生物量,但同时降低了高光斑块分株的生物量,对克隆片段总体的生物量积累无显著影响,且这一结果不受资源输送方向的影响;克隆整合降低了异质性光照下克隆分株间根冠比的差异,加大了克隆分株间净光合速率的差异,且倾向于提高生长在高光斑块分株的比叶面积;克隆整合虽然并不能促进薇甘菊匍匐茎克隆片段在异质性光照生境下总体的生长,但可以促进低光斑块下分株的生长,因而,克隆整合可促进薇甘菊从开阔生境向低光生境(森林、杂草群落等)的入侵能力,因此,克隆整合特性是薇甘菊对异质性光照环境的重要适应对策之一。  相似文献   

10.
研究了不同海拔高度(1800和3900m)的匍匐茎克隆植物野草莓(Fragaria vesca)种群对光照和养分资源斑块性分布生境的响应。结果表明:与资源的空间同质性处理(Ⅰ)和(Ⅱ)相比,资源的空间异质性处理(Ⅲ)和(Ⅳ)中2个种群的野草莓的近端、远端分株部分和整个克隆片段的生物量和分株数均明显增加。当近端分株部分经历低光高养,而与其相连的远端分株部分经历高光低养时,相比于整个克隆片段都处于低光高养的同质性生境,来自2个海拔的种群的近端分株部分都会增加对根的生物量分配;当近端分株部分经历高光低养,而与其相连的远端分株部分经历低光高养时,相比于整个克隆片段都处于低光高养的同质性生境,来自2个海拔的种群的近端分株部分都会减少对根的生物量分配,远端分株部分也被观察到类似的生物量分配格局。相比于高光低养的同质性生境,当与低光高养的远端分株部分相连时,经历高光低养的近端分株部分有更大的叶面积;相比于低光高养的同质性生境,当与低光高养近端分株部分相连时,经历高光低养的远端分株部分有更大的叶面积。结果表明,野草莓在资源交互斑块性生境中发生了克隆内分工,克隆内分工有利于克隆植物对异质性资源的利用,对克隆植物在资源斑块性分布生境中的生存和生长具有重要的意义。  相似文献   

11.
The relationship between Native Americans and the Euro-American settlers has evolved from the latter seeking to end the separate identity of the former to one in which the U.S. government uses Native rights to control large-scale resource problems. This new relationship arose out of a need to control water in Western states for irrigation, but has expanded into other areas. The Navajo sheep reductions of the 1930s and 1940s may be seen as an instance of this relationship. Concerns about siltation behind the Hoover Dam justified a program that dramatically transformed the Navajo economy. A second case concerns conflict over a caribou herd in northwestern Alaska. The conflict eventually led to the Federal government taking management of fish and game on Federal lands back from the state government. Both these cases show the development of a technocracy, based on Federal trusteeship over Native resources, concerned with the control of nature similar to that observed in Wittfogel's writings on Chinese irrigation.  相似文献   

12.
Resource defense in a group-foraging context   总被引:5,自引:2,他引:3  
When foraging in groups, animals frequently use either scrambleor contest tactics to obtain food at clumps found by others.The question of which competitive tactic should be used hasbeen addressed from two different perspectives: a simple optimalityapproach and a game theoretic approach. Surprisingly, both approachesmake strikingly different predictions about how per-capita frequencyof aggression within groups should change as a function of foodabundance and competitor density. Resource defense theory typicallypredicts dome-shaped relationships between the per-capita frequencyof aggression and both food abundance and competitor density,whereas game theoretic models predict an increase in aggressionwith competitor density and a decline in aggression with increasedfood abundance. We developed a game theoretic model to explorewhether the predictions of resource defense theory and the gametheoretic approach can be reconciled. Our model assumes thatplayers have different competitive abilities and can adopt rolesof either finder or joiner that affect the quantity of foodthat can be gained from a food clump. In accordance with earliergame theoretic models, we predict an increase in aggressionwith competitor density when animals compete by pair-wise contests.However, when food clumps can be challenged by more than onecompetitor, both the costs and benefits of defending increasewith competitor density, which results in a dome-shaped relationshipbetween the two variables. Our model predicts that aggressionshould always decrease as the density of food clumps increases.  相似文献   

13.
三种木通属植物的地理分布与资源调查   总被引:4,自引:0,他引:4  
木通属(AkebiaDecaisne)植物为我国传统药用植物,有着2000多年的药用历史,具有很高的药用价值;叶、花、果观赏性强,果肉营养丰富,可鲜食或加工,开发潜力巨大。作者对3种具有经济价值的木通属植物(五叶木通Akebia quinata(Houttuyn)Decaisne、三叶木通A.trifoliatassp.trifoliata和白木通A.trifoliatassp.austra-lis)的地理分布、形态学和农艺学特征以及资源现状进行了调查。结果发现,五叶木通主要分布于中国东南部及长江流域,由于长期的过度采收使野生资源遭到严重破坏;三叶木通广泛分布于华中及黄河流域,秦岭沿线分布较多,野生资源蕴藏量匮乏,目前已相继建立GAP栽培基地并作为保健水果进行开发;白木通分布于华南及长江流域各省区,资源丰富,但目前开发利用较少。为保证野生资源的可持续利用,应控制木通属植物的过度采收,加强白木通的合理开发利用,进行更广泛的资源调查、收集和评价,同时建立栽培驯化基地,推广优质、高产栽培技术,培育出品质优良,经济价值高,适合药用、观赏、食用或加工等不同需要的品种,促进木通产业的健康发展。  相似文献   

14.
粮果间作种植模式的资源利用与管理   总被引:11,自引:1,他引:10  
粮果间作种植模式的资源利用与管理贺明荣,冷寿慈,李增嘉,张明亮(山东农业大学,泰安271018)ResourceUtilizationandItsManagementinGrainandFruitIntercroppingSystem.¥HeMing...  相似文献   

15.
Resource Optimization and Symbiotic Nitrogen Fixation   总被引:6,自引:1,他引:5  
In temperate forests, symbiotic nitrogen (N) fixation is restricted to the early phases of succession despite the persistence of N limitation on production late in succession. This paradox has yet to be explained adequately. We hypothesized that the restriction of N fixation to early stages of succession results from the optimization of resource allocation in the vegetation. Because of this optimization, N fixation should be restricted to periods when fixation is less costly than N uptake. Our analysis differs from others in the way we calculate the cost of N uptake; we assess the cost of N uptake as the amount of carbon (C) that could be assimilated if the resources necessary to acquire one gram of N from the soil were allocated instead to photosynthesis. We then simulate N fixation as an asymptotic function of the difference in cost between N uptake and N fixation and proportional to the abundance of host tissues for the N-fixing symbionts. The factors that contribute to conditions that favor N fixation are (a) elevated-carbon dioxide (CO2) concentrations, (b) an open canopy, (c) low available N in the soil, and (d) a soil volume already well exploited by roots. Our results indicate that changes in the relative cost of uptake vs fixation can explain most of the pattern in fixation through both primary and secondary succession, but that competitive interactions with nonfixing species play a role in the final exclusion of fixation in later stages of succession. Received 26 September 2000; accepted 31 January 2001.  相似文献   

16.
Resource assessment in hermit crabs: the worth of their own shell   总被引:1,自引:0,他引:1  
Animals gather information about the quality of a resource throughits assessment and behave accordingly as a result of adaptivemotivational changes. In the hermit crab Pagurus longicarpus,we investigated whether an individual was affected in its motivationto acquire a new shell by the quality of the domicile shell(own resource value [ORV]), of the offered shell (external resourcevalue [ERV]), or of both and asked whether its motivation wasaltered by the information gathered during shell investigation.We analyzed the behavior of hermit crabs inhabiting shells ofdiffering qualities and compared their willingness to acquirean offered shell—optimal, smaller than optimal, or largerthan optimal—by measuring the latency to approach it,the number of shell investigation, and its total duration. Crabsin smaller shells (SSs) approached more quick and often theoffered shell, whereas crabs in larger shells investigated theoffered shell more thoroughly. The readiness of crabs to approachthe offered shell and the extent of its investigation were independentof the ERV but were exclusively affected by the ORV, whereasthe number and duration of shell investigation did not changewith time as investigation proceeded, except for crabs in SSs.These results suggest that P. longicarpus' motivation to acquirea new shell is exclusively influenced by the value of the shellit inhabits rather than by the quality of the shell it is offeredand that this species does not gather—or does not use—informationabout ERV during investigation.  相似文献   

17.
花椒资源与开发利用现状调查   总被引:15,自引:1,他引:14  
本文介绍了我国重点产区的花椒资源与开发利用现状。  相似文献   

18.
William Ascher 《Ecosystems》2001,4(8):742-757
To cope with the daunting challenges posed by system complexity while maximizing their organizational interests, resource management institutions must implement strategies aimed at reducing some of the particular dimensions of complexity. Virtually all of the recent initiatives to improve resource management—ecosystem management, adaptive management, stakeholder negotiation, disturbance prevention, multiple mandates for resource management agencies, resource homogenization, restoration ecology, the creation of protected areas, the restoration of local-user rights, and algorithmic resource exploitation rules—are vulnerable to inappropriate interest-driven simplifications, many of which result from patterns of perverse learning. A research agenda designed to identify better means of coping with complexity and the effects of organizational interests could help to improve resource and environmental management. Received 4 October 2000; accepted 15 June 2001.  相似文献   

19.
Human influence is now so pervasive that every ecosystem on Earth is being managed, whether intentionally or inadvertently. It is therefore imperative for scientists and managers to work together so that appropriate management regimes can be put in place wherever possible. However, it is not always clear what is appropriate, and the difficulties that often arise when scientists and managers work together can be even further compounded by the inclusion of lay stakeholders in the decision-making process. The expansion of interdisciplinary undergraduate and graduate programs would help both scientists and managers to deal more effectively with sociological issues and to understand how economic and demographic changes impact on natural resources. In addition, continuing education programs in these areas should be made available to established professionals to help them deal with new challenges. The concept of ecosystem services should be used to communicate the importance of various ecosystem components and processes to a broader audience. Consensus on a management regime can often be achieved through adaptive management. The process by which interdisciplinary collaboration can lead to new insights and research initiatives is exemplified by a resource management study on the island of Kosrae, Federated States of Micronesia. As a paradigm of natural resource management, microcosms like this small island community offer a unique opportunity for training and education. Received 4 October 2000; accepted 20 March 2001.  相似文献   

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