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微生态学的崛起与观念革命 总被引:2,自引:0,他引:2
康白 《中国微生态学杂志》1993,(1)
1.微观层次生态学是研究生物与外环境相互依赖,相互制约的生命科学。传统的生态学是研究植物、动物及人类个体或由个体组成的种群和群落的生态学规律。这是生态学的宏观层次,因而也可叫作宏观生态学。生态学的另一个层次就是微观生态学。微观生态学是生态学的微观层次,其研究对象是植物、动物及人类个体以下的 相似文献
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川蔓藻是近海生态系统中重要的初级生产者, 了解它的生态学特征对于河口海岸带的生态修复具有重要意义。本文结合我们在天津滨海湿地生态修复工程中对于川蔓藻的研究成果, 从以下几个方面探讨了川蔓藻的生态学特征及其与环境的关系: 川蔓藻对极端环境因子的适应; 川蔓藻在资源分配上的繁殖策略; 川蔓藻的矿质营养代谢以及对栖息地生物地球化学循环的影响; 川蔓藻种群衰退的原因; 川蔓藻在环境修复中的应用。其中着重讨论了川蔓藻对环境变化的响应, 并结合我们的研究工作展望了它在环境工程与近岸水体修复中的应用潜力。 相似文献
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我国热带亚热带几种人工林体内营养结构特征 总被引:6,自引:0,他引:6
营养是植物的一种资源 ,植物如何在体内分配这一资源影响到它对环境的适应性。植物体内的营养含量在某种程度上还反映了环境中营养供应的丰缺 ,同时 ,它又是生态系统营养循环的一个组成部分。国外曾对植物的营养含量特征进行过大量的研究 ,积累了相当多的资料 ,代表性工作如Jordan[12 ](亚马逊雨林 ) ,Whittaker[13 ] (HubbarkBrook生态站森林 ) ,Woodwell[14 ] (Brookhaven森林 )等 ,随着计算机模拟技术的发展 ,这些资料成了进行生态模拟不可缺少的珍贵资料。我国尽管在 2 0世纪 5 0年代就开… 相似文献
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沉水植物川蔓藻的生态学特征及其对环境变化的响应 总被引:1,自引:0,他引:1
川蔓藻是近海生态系统中重要的初级生产者,了解它的生态学特征对于河口海岸带的生态修复具有重要意义。本文结合我们在天津滨海湿地生态修复工程中对于川蔓藻的研究成果,从以下几个方面探讨了川蔓藻的生态学特征及其与环境的关系:川蔓藻对极端环境因子的适应;川蔓藻在资源分配上的繁殖策略;川蔓藻的矿质营养代谢以及对栖息地生物地球化学循环的影响;川蔓藻种群衰退的原因;川蔓藻在环境修复中的应用。其中着重讨论了川蔓藻对环境变化的响应,并结合我们的研究工作展望了它在环境工程与近岸水体修复中的应用潜力。 相似文献
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栖息地环境对种群营养生态位的影响——以黄颡鱼为例 总被引:1,自引:0,他引:1
生态位是生态学研究的基础,目前关于环境指标是否直接影响营养生态位的分析研究很少。以高营养级鱼类黄颡鱼为研究对象,利用稳定同位素分析和相关分析,在太湖贡湖湾研究了氨氮、亚硝酸盐氮、硝酸盐氮、总氮、溶解性总氮、溶解性正磷酸盐、总磷、溶解性总磷、叶绿素等多个栖息地水环境因子对鱼类种群营养生态位的影响。结果表明,栖息地水环境对黄颡鱼总营养生态位影响不大,但部分栖息地水环境因子对分项营养生态位(包括浮游、底栖与肉食性)有影响。研究得知,栖息地水环境因子中氨氮、硝酸盐氮、总氮、溶解性总氮及溶解性总磷与浮游食性营养生态位显著正相关,氨氮、硝酸盐氮、总氮、溶解性总氮及溶解性总磷与肉食性营养生态位显著负相关,而底栖食性则主要受溶解性总磷的影响,与其显著正相关。水环境因子的季节变化影响水体中饵料资源的分布,进而影响鱼类的食物组成。 相似文献
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根际营养环境与持续农业 总被引:16,自引:0,他引:16
根据pH,Eh、分泌物及微生物等营养特征极大地影响土壤中养分的利用率,也制约着外源污染物从土壤经根际进入植物体内的迁移过程,并进而影响到农产品品质。此外,与土传植物病害的发生和控制,植物对土壤营养逆境的适应性和对矿质营养基因型的差异,植物生化互作效应及土壤中温室效应气体的排放等重大生态和环境问题有关。因此,采取合理的措施调控根际营养环境,对促进农业的持续发展是十分重要的。 相似文献
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S. Boudsocq S. Barot N. Loeuille 《Proceedings. Biological sciences / The Royal Society》2011,278(1704):449-457
Although plant strategies for acquiring nutrients have been widely studied from a functional point of view, their evolution is still not well understood. In this study, we investigate the evolutionary dynamics of these strategies and determine how they influence ecosystem properties. To do so, we use a simple nutrient-limited ecosystem model in which plant ability to take up nutrients is subject to adaptive dynamics. We postulate the existence of a trade-off between this ability and mortality. We show that contrasting strategies are possible as evolutionary outcomes, depending on the shape of the trade-off and, when nitrogen is considered as the limiting nutrient, on the intensity of symbiotic fixation. Our model enables us to bridge these evolutionary outcomes to classical ecological theories such as Hardin''s tragedy of the commons and Tilman''s rule of R*. Evolution does not systematically maximize plant biomass or primary productivity. On the other hand, each evolutionary outcome leads to a decrease in the availability of the limiting mineral nutrient, supporting the work of Tilman on competition between plants for a single resource. Our model shows that evolution can be used to link different classical ecological results and that adaptation may influence ecosystem properties in contrasted ways. 相似文献
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土壤养分分布具有高度空间异质性, 植物的根系觅养行为是其对土壤养分异质性的一种适应。不同植物为了适应养分异质性会产生不同的根系觅养行为, 通过调整自身的根系觅养范围、觅养精度和觅养速度来更好地吸收利用土壤中的养分。外来植物与本地植物的竞争是决定其成功入侵的重要因素, 土壤养分等环境因素会影响它们之间的竞争关系。近年来, 外来入侵植物的觅养行为逐渐受到人们的关注, 关于入侵植物根系觅养行为的研究成果陆续出现: (1)总体来看, 外来入侵植物具有较强的根系觅养能力, 但根系觅养范围与觅养精度之间的权衡关系还不确定; (2)营养异质性会影响入侵植物与本地植物之间的竞争, 反过来, 二者之间的竞争也会影响根系觅养行为对营养异质性的响应; (3)丛枝菌根真菌(arbuscular mycorrhizal fungi, AMF)能够提高入侵植物的根系觅养能力, 外来植物入侵能够改变入侵植物对AMF的偏好性, 形成AMF对入侵的正反馈作用, 而本地植物与AMF的相互作用也会影响入侵植物的竞争力。未来还应加强营养异质环境下种间竞争和AMF共生对入侵植物根系觅养行为的影响机制研究, 以及全球变化背景下入侵植物根系觅养行为的变化与机制方面的研究, 可以更深入地认识外来植物的觅养行为在其成功入侵中的作用, 并为利用营养调控来防控入侵植物提供理论依据。 相似文献
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Janet I. Sprent 《Plant and Soil》1994,161(1):1-10
This paper examines the general biology of mycorrhizal associations alongside the wide range of alternative trophic adaptations
which higher plants may employ when competing for limited resources of specific nutrients within an ecosystem. All examples
described come from highly nutrient-impoverished heathlands or open woodlands of the kwongan of southwest Australia. An account
is given of the general patterns of rooting morphology and their association with various mycorrhizal and non-mycorrhizal
nutrient-acquiring strategies, including various forms of parasitism, epiparasitism, autotrophy with or without mycorrhizal
association. Taxonomic affinities of each grouping are examined alongside growth and life form characteristics.
A case study of patterns of utilization of a specific nutrient, nitrogen in a Banksia woodland ecosystem is presented to illustrate
how a multifaceted approach can be used for studying species responses and interactions. The study categorizes species according
to nitrate-utilizing ability and suggests how 15N natural abundance of soil and plant components and organic solutes of nitrogen is xylem might be utilized to separate species
into different trophic categories. Response of the ecosystem to fire is examined in respect of the nutritional interrelationships
of component species as the ecosystem changes from being nitrate dominant immediately after fire to increasingly ammonium-producing
thereafter.
The paper concludes by examining generally trophic relationships within whole ecosystems and outlines some of the challenges
for future research in this connection. 相似文献
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Remans R Flynn DF DeClerck F Diru W Fanzo J Gaynor K Lambrecht I Mudiope J Mutuo PK Nkhoma P Siriri D Sullivan C Palm CA 《PloS one》2011,6(6):e21235
Background
In Sub-Saharan Africa, 40% of children under five years in age are chronically undernourished. As new investments and attention galvanize action on African agriculture to reduce hunger, there is an urgent need for metrics that monitor agricultural progress beyond calories produced per capita and address nutritional diversity essential for human health. In this study we demonstrate how an ecological tool, functional diversity (FD), has potential to address this need and provide new insights on nutritional diversity of cropping systems in rural Africa.Methods and Findings
Data on edible plant species diversity, food security and diet diversity were collected for 170 farms in three rural settings in Sub-Saharan Africa. Nutritional FD metrics were calculated based on farm species composition and species nutritional composition. Iron and vitamin A deficiency were determined from blood samples of 90 adult women. Nutritional FD metrics summarized the diversity of nutrients provided by the farm and showed variability between farms and villages. Regression of nutritional FD against species richness and expected FD enabled identification of key species that add nutrient diversity to the system and assessed the degree of redundancy for nutrient traits. Nutritional FD analysis demonstrated that depending on the original composition of species on farm or village, adding or removing individual species can have radically different outcomes for nutritional diversity. While correlations between nutritional FD, food and nutrition indicators were not significant at household level, associations between these variables were observed at village level.Conclusion
This study provides novel metrics to address nutritional diversity in farming systems and examples of how these metrics can help guide agricultural interventions towards adequate nutrient diversity. New hypotheses on the link between agro-diversity, food security and human nutrition are generated and strategies for future research are suggested calling for integration of agriculture, ecology, nutrition, and socio-economics. 相似文献16.
Many tropical animals inhabit mosaic landscapes including human-modified habitat. In such landscapes, animals commonly adjust feeding behavior, and may incorporate non-natural foods. These behavioral shifts can influence consumers' nutritional states, with implications for population persistence. However, few studies have addressed the nutritional role of non-natural food. We examined nutritional ecology of wild blue monkeys to understand how dietary habits related to non-natural foods might support population persistence in a mosaic landscape. We documented prevalence and nutritional composition of non-natural foods in monkey diets to assess how habitat use influenced their consumption, and their contribution to nutritional strategies. While most energy and macronutrients came from natural foods, subjects focused non-natural feeding activity on five exotic plants, and averaged about a third of daily calories from non-natural foods. Most non-natural food calories came from non-structural carbohydrates and least from protein. Consumption of non-natural foods related to time in human-modified habitats, which two groups used non-randomly. Non-natural and natural foods were similar in nutrients, and the amount of non-natural food consumed drove variation in nutritional strategy. When more daily calories came from non-natural foods, females consumed a higher ratio of non-protein energy to protein (NPE:P). Females also prioritized protein while allowing NPE:P to vary, increasing NPE while capitalizing on non-natural foods. Overall, these tropical mammals achieved a similar nutrient balance regardless of their intake of non-natural foods. Forest and forest-adjacent areas with non-natural vegetation may provide adequate nutrient access for consumers, and thus contribute to wildlife conservation in mosaic tropical landscapes. 相似文献
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Nathan I. Morehouse Takefumi Nakazawa Christina M. Booher Punidan D. Jeyasingh Matthew D. Hall 《Oikos》2010,119(5):766-778
Recent advances in nutritional ecology, particularly arising from Ecological Stoichiometry and the Geometric Framework for nutrition, have resulted in greater theoretical coherence and increasingly incisive empirical methodologies that in combination allow for the consideration of nutrient‐related processes at many levels of biological complexity. However, these advances have not been consistently integrated into the study of sexual differences in reproductive investment, despite contemporary emphasis on the material costs associated with sexually selected traits (e.g. condition‐dependence of exaggerated ornaments). Nutritional ecology suggests that material costs related to sex‐specific reproductive traits should be linked to quantifiable underlying differences in the relationship between individuals of each sex and their foods. Here, we argue that applying nutritionally‐explicit thought to the study of sexual reproduction should both deepen current understanding of sex‐specific phenomena and broaden the tractable frontiers of sexual selection research. In support of this general argument, we examine the causes and consequences of sex‐specific nutritional differences, from food selection and nutrient processing to sex‐specific reproductive traits. At each level of biological organization, we highlight how a nutritionally‐explicit perspective may provide new insights and help to identify new directions. Based on predictions derived at the individual level, we then consider how sex‐specific nutrient limitation might influence population growth, and thus potentially broader patterns of life history evolution, using a simple population dynamics model. We conclude by highlighting new avenues of research that may be more accessible from this integrative perspective. 相似文献
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The Geometric Framework approach in nutritional ecology postulates that animals attempt to balance the consumption of different nutrients rather than simply maximizing energetic gain. The intake target with respect to each nutrient maximizes fitness in a specific dimension and any difference between individuals in intake target therefore represents alternative behavioral and fitness maximization strategies. Nutritional interactions are a central component of all social groups and any inter-individual variation in intake target should therefore have a significant influence on social dynamics. Using the honeybee colony as an experimental model, we quantified differences in the carbohydrate intake target of individual foragers using a capillary feeder (CAFE) assay. Our results show that the bees did not simply maximize their net energetic gain, but combined sugar and water in their diet in a way that brought them to an intake target equivalent to a 33% sucrose solution. Although the mean intake target with respect to the nutrients sucrose and water was the same under different food choice regimens, there was significant inter-individual variation in intake target and the manner in which individuals reached this target, a variation which suggests different levels of tolerance to nutrient imbalance. We discuss our results in the context of how colony performance may be influenced by the different nutrient balancing strategies of individual members and how such nutritional constraints could have contributed to the evolution of sociality. 相似文献
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为了更有效地从土壤中获取养分, 植物根系在长期的进化与适应中产生了一系列塑性反应, 以响应自然界中广泛存在的时空异质性。同时, 植物根系的养分吸收也要面对来自种内和种间的竞争。多种因素都会影响植物根竞争的结果, 包括养分条件、养分异质性的程度、根系塑性的表达等。竞争会改变植物根系的塑性反应, 比如影响植物根系的空间分布; 植物根系塑性程度差异也会影响竞争。已有研究发现根系具有高形态塑性和高生理塑性的植物在长期竞争过程中会占据优势。由于不同物种根系塑性的差异, 固定的对待竞争的反应模式在植物根系中可能并不存在, 其响应随竞争物种以及土壤环境因素的变化而变化。此外, 随着时间变化, 根系塑性的反应及其重要性也会随之改变。植物对竞争的反应可能与竞争个体之间的亲缘关系有关, 有研究表明亲缘关系近的植物可能倾向于减小彼此之间的竞争。根竞争对植物的生存非常重要, 但目前还没有研究综合考虑植物的各种塑性在根竞争中的作用。另外根竞争对群落结构的影响尚待深入的研究。 相似文献
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The role of functional traits and trade-offs in structuring phytoplankton communities: scaling from cellular to ecosystem level 总被引:6,自引:0,他引:6
Trait-based approaches to community structure are increasingly used in terrestrial ecology. We show that such an approach, augmented by a mechanistic analysis of trade-offs among functional traits, can be successfully used to explain community composition of marine phytoplankton along environmental gradients. Our analysis of literature on major functional traits in phytoplankton, such as parameters of nutrient-dependent growth and uptake, reveals physiological trade-offs in species abilities to acquire and utilize resources. These trade-offs, arising from fundamental relations such as cellular scaling laws and enzyme kinetics, define contrasting ecological strategies of nutrient acquisition. Major groups of marine eukaryotic phytoplankton have adopted distinct strategies with associated traits. These diverse strategies of nutrient utilization can explain the distribution patterns of major functional groups and size classes along nutrient availability gradients. 相似文献