胁迫生态学研究进展

介绍了胁迫及胁迫生态学的定义,划分了胁迫的种类,阐述了胁迫生态学的研究意义和主要研究内容。受胁生态系统的症状包括营养循环,初级生产力,物种多样性,优势种群个体大小,演替方向,发病率和种群数量等的变化。在一定程度和一定时段内,生态系统的平衡机制可以缓解胁迫的影响;一旦胁迫超过自稳定能力,生态系统将进一步退化甚至发生不可逆转的崩溃。     

城市生态学基本原理的探讨

城市生态学是一门正在发展中的生态学分支,因其产生历史较短,而尚未形成一套成熟的理论体系和研究方法.本文试图应用生态学基本原理来探讨城市生态系统的性质和特点,初步提出了城市生态学的一些原理和研究城市生态系统的指导原则,并提出了环境承载力—人类社会行为和生态环境之间的界面在城市生态系统研究的地位和作用.     

生态学范式下的清洁生产、产业生态和循环经济分析

运用生态学理论,从个体生态、种群生态、群落生态和生态系统生态4个生态学尺度上对清洁生产、产业生态和循环经济进行类比分析,论述了清洁生产与个体生态学、生态产业与种群生态学和群落生态学、循环经济与生态系统生态学的内在联系及3者之间的相容和递进关系,指出当前清洁生产和产业生态研究与实践中存在的局限性,认为提高清洁生产实施的层次,扩大清洁生产实施的范围,将产业生态研究上升到产业生态系统层面是清洁生产和产业生态未来研究和实践的方向,3者在不同层面的实践将最终推动人类不断接近可持续发展的理想目标.     

化学污染物对珊瑚礁生态系统的影响研究进展

化学污染物是影响珊瑚礁生态系统健康的重要因素之一。随着我国社会经济的发展,沿海农业活动、城市工业化以及旅游业的发展导致珊瑚礁生长区的化学污染物浓度越来越高。珊瑚礁生态系统长期在化学污染物的联合胁迫下,生态风险指数日益增加,受到国内外研究者的极大关注。本文综述了国内外该领域的重要研究进展,并从个体、细胞和分子水平重点介绍了化学污染物对珊瑚的影响,主要包括：(1)珊瑚礁对重金属和多环芳烃有明显的富集作用,可以作为该海域化学污染物污染水平的外在反映;(2)化学污染物对珊瑚幼体的影响程度比成体大;(3)抗氧化酶和特定的功能基因可被用作生物标记物来监测珊瑚礁生态系统的健康状况。最后,对我国未来珊瑚礁生态系统的研究方向进行展望,建议在典型珊瑚礁海域进行长期的生态学监测,结合室内胁迫实验,筛选出敏感的生物标志物(biomarker),为今后珊瑚礁生态系统的保护提供基础信息,并对其可能存在的环境风险进行评价。     

农村生态系统健康的基本内涵及评价体系探索

生态系统健康是研究人类活动、社会经济组织、自然系统和人类健康的综合性学科,是人类社会可持续发展的保证,国内外对不同类型的生态系统健康进行了大量研究,指出生态系统健康是在时间上具有维持其组织结构、自我调节和对胁迫受损的恢复能力,实现生态系统的稳定性和可持续性.农村生态系统是一类自然一人工复合生态系统,在综合分析农业生态系统健康和城市生态系统健康概念的基础上,提出农村生态系统是指在不同区域范围的农村地域内,不同类型生态系统间的相互能量关系,以及农村人群和周围环境的相互影响与相互作用的总和.农村生态系统健康是指农村生态系统能够实现农村环境健康目标、生态系统活力目标、农业生产与乡镇企业发展目标,并具有一定的自我调节和对胁迫受损的恢复能力.通过分析已有生态系统健康评价所采用的指标体系,结合农村生态系统的特性,研究构建了由环境健康目标、生态系统活力目标和功能目标组成的农村生态系统健康评价的框架体系,以期明确农村生态系统健康的内涵,为开展评价研究建立初步基础.     

湿地土壤动物及其与湿地恢复的关系

土壤动物是湿地生态系统物质循环和能量流动的关键环节,也是湿地生态系统演化的重要驱动因子,湿地土壤动物的动态变化可以作为湿地退化和恢复响应的重要生态指标。近年来基于湿地土壤动物群落生态学的单一研究颇多,对湿地土壤动物及其与环境因子关系的研究亦取得了长足进展,但关于湿地土壤动物和湿地退化与恢复的研究鲜有报道。本文论述了湿地土壤动物在湿地恢复过程的机制和优势,阐述了湿地土壤动物研究现状与进展,表明湿地土壤动物是湿地生态系统和湿地生物多样性的重要组成部分,已成为湿地恢复的重要指标。通过分析湿地土壤动物及其与湿地恢复的关系,认为湿地土壤动物的动态变化可以较好地反映退化和恢复过程中生态功能的变化,建议深入探索土壤动物对湿地退化和恢复的响应机制。关于土壤动物对湿地生态指示功能的研究,是恢复生态学和湿地重建领域未来需要研究解决的一个重要问题,是研究人为干扰过程以及湿地恢复过程中土壤动物变化规律的关键。今后要进一步融合土壤动物和整个湿地生态系统的研究为一体,把不同强度干扰下湿地土壤动物生态学及其与不同土地利用方式下土壤质量及湿地植被结合起来,从土壤动物群落特征变化角度阐明湿地生态系统对不同强度干扰的响应机制,为深入探索不同强度干扰下湿地生态系统的退化过程和机制,从而为退化湿地恢复与部分重建的生物学与生态学基础提供科学依据。     

人类福祉及其在生态学研究中的应用与展望

维持和改善人类福祉、促进可持续发展已成为现阶段生态学研究的重要议题和发展新方向,但目前人类福祉与生态学研究工作的结合还很有限。基于此,该文介绍了人类福祉的概念及其发展,综述了人类福祉评估的指标体系,总结了人类福祉在生态学研究中集中体现的3个方面:生态系统服务与人类福祉的关系、人类福祉的时空分布特征和生态系统变化的驱动力对人类福祉的影响,并对今后的主要研究方向及挑战作展望。构建评估人类福祉的综合指标体系、定量化人类福祉与生态系统服务之间的关系以及加强局地尺度的人类福祉研究是人类福祉在生态学领域研究中的前沿问题,这些科学问题的解决将促进人类福祉研究科学地应用于各级决策管理之中。     

我国中亚热带人工林水热通量对干旱差异响应的模拟研究

季节性干旱现象在我国中亚热带地区时有发生,为了研究该区域大气-生态系统之间的相互作用关系及其碳水收支状况,2002年起在江西省千烟洲(26.7°N,115.1°E)人工林生态系统建立了通量观测塔。2003年7月该人工林生态系统遭遇了历史上少有的高温少雨天气,本研究应用基于生理生态学过程的EALCO(Ecological Assimilation of Land and Climate Observation)模型及2003和2004年通量观测数据对该生态系统的水热通量进行了模拟,同时分析了干旱胁迫对它们产生的影响。结果显示,模型能够很好的模拟该生态系统的能量通量的日变化,净辐射、显热和潜热通量模拟值与实测值相关系数的平方(R2)及标准差分别为0.99和8.05 W.m-2;0.81和41.02 W.m-2;0.90和31.49 W.m-2,模型可以解释87%的日蒸散量的变化。从模拟结果看,2003年7月下旬(发生较严重干旱胁迫)较2004年同期(干旱程度轻)相比,冠层及土壤水势下降约2倍,植物蒸腾的日变化形式改变,根系吸水滞后冠层蒸腾的时间缩短约半小时,冠层导度下降40%～60%。模拟与观测结果均表明,200...     

城市生态系统承载力研究进展

承载力一词来自生态学，最初应用于对自然生态系统中生物数量的研究。从城市生态学与城市生态系统理论的发展角度介绍了城市生态学中承载力一词含义及其发展过程，并重点介绍了国内外学者对资源承载力、环境承载力及生态承载力的研究与应用。针对城市所具有的明显自然-社会-经济复合生态系统特征，笔者认为应该在城市生态系统承载力研究中强调社会经济系统能力的贡献。     

中国生态系统研究网络（CERN）的科学目标与近期方向

生态与环境是人类社会可持续发展的基础。进入20世纪90年代以来,生态学研究愈来愈受到广泛重视,已成为自然科学和社会科学共同关注的重点领域。近年,国际生态学联合会和美国生态学会都提出了相应的生态学研究计划和优先领域,其中全球变化、生物多样性和生态系统的可持续性被列为生态学的研究前沿。     

From individuals to ecosystem function: toward an integration of evolutionary and ecosystem ecology

An important goal in ecology is developing general theory on how the species composition of ecosystems is related to ecosystem properties and functions. Progress on this front is limited partly because of the need to identify mechanisms controlling functions that are common to a wide range of ecosystem types. We propose that one general mechanism, rooted in the evolutionary ecology of all species, is adaptive foraging behavior in response to predation risk. To support our claim, we present two kinds of empirical evidence from plant-based and detritus-based food chains of terrestrial and aquatic ecosystems. The first kind comes from experiments that explicitly trace how adaptive foraging influences ecosystem properties and functions. The second kind comes from a synthesis of studies that individually examine complementary components of particular ecosystems that together provide an integrated perspective on the link between adaptive foraging and ecosystem function. We show that the indirect effects of predators on plant diversity, plant productivity, nutrient cycling, trophic transfer efficiencies, and energy flux caused by consumer foraging shifts in response to risk are qualitatively different from effects caused by reductions in prey density due to direct predation. We argue that a perspective of ecosystem function that considers effects of consumer behavior in response to predation risk will broaden our capacity to explain the range of outcomes and contingencies in trophic control of ecosystems. This perspective also provides an operational way to integrate evolutionary and ecosystem ecology, which is an important challenge in ecology.     

Ecoregions and ecosystem management in China

Ecological regionalization is a base for rational management and sustainable utilization of ecosystems and natural resources. It can provide a scientific basis for constructing healthy ecological environments and making policies of environmental management. In this paper, based on synthetic analysis of the characteristics of the ecology and environments of China, the principles of ecological regionalization are discussed, and indices and nomenclature of ecological regionalization are proposed. The ecoregions on a national scale are divided. The results show that there are 3 domains, 13 ecoregions and 57 ecodistricts. The present scheme can be used as a framework for ecosystem assessment and management. Based on the ecoregions, measurements of management for forest, grassland, agriculture and wetland ecosystems are recommended. The experience and information can be used within and beyond the national scale for land-use planning, biodiversity conservation and ecosystem restoration.     

Microbial stress-response physiology and its implications for ecosystem function

Microorganisms have a variety of evolutionary adaptations and physiological acclimation mechanisms that allow them to survive and remain active in the face of environmental stress. Physiological responses to stress have costs at the organismal level that can result in altered ecosystem-level C, energy, and nutrient flows. These large-scale impacts result from direct effects on active microbes' physiology and by controlling the composition of the active microbial community. We first consider some general aspects of how microbes experience environmental stresses and how they respond to them. We then discuss the impacts of two important ecosystem-level stressors, drought and freezing, on microbial physiology and community composition. Even when microbial community response to stress is limited, the physiological costs imposed on soil microbes are large enough that they may cause large shifts in the allocation and fate of C and N. For example, for microbes to synthesize the osmolytes they need to survive a single drought episode they may consume up to 5% of total annual net primary production in grassland ecosystems, while acclimating to freezing conditions switches Arctic tundra soils from immobilizing N during the growing season to mineralizing it during the winter. We suggest that more effectively integrating microbial ecology into ecosystem ecology will require a more complete integration of microbial physiological ecology, population biology, and process ecology.     

Advancing the Integration of History and Ecology for Conservation

Abstract: The important role of humans in the development of current ecosystems was recognized decades ago; however, the integration of history and ecology in order to inform conservation has been difficult. We identified four issues that hinder historical ecological research and considered possible solutions. First, differences in concepts and methods between the fields of ecology and history are thought to be large. However, most differences stem from miscommunication between ecologists and historians and are less substantial than is usually assumed. Cooperation can be achieved by focusing on the features ecology and history have in common and through understanding and acceptance of differing points of view. Second, historical ecological research is often hampered by differences in spatial and temporal scales between ecology and history. We argue that historical ecological research can only be conducted at extents for which sources in both disciplines have comparable resolutions. Researchers must begin by clearly defining the relevant scales for the given purpose. Third, periods for which quantitative historical sources are not easily accessible (before AD 1800) have been neglected in historical ecological research. Because data from periods before 1800 are as relevant to the current state of ecosystems as more recent data, we suggest that historical ecologists actively seek out data from before 1800 and apply analytic methods commonly used in ecology to these data. Fourth, humans are not usually considered an intrinsic ecological factor in current ecological research. In our view, human societies should be acknowledged as integral parts of ecosystems and societal processes should be recognized as driving forces of ecosystem change.     

Using the expert model PERPEST to translate measured and predicted pesticide exposure data into ecological risks

An important topic in the registration of pesticides and the interpretation of monitoring data is the estimation of the consequences of a certain concentration of a pesticide for the ecology of aquatic ecosystems. Solving these problems requires predictions of the expected response of the ecosystem to chemical stress. Up until now, a dominant approach to come up with such a prediction is the use of simulation models or safety factors. The disadvantage of the use of safety factors is a crude method that does not provide any insight into the concentration–response relationships at the ecosystem level. On the other hand, simulation models also have serious drawbacks like that they are often very complex, lack transparency, their implementation is expensive and there may be a compilation of errors, due to uncertainties in parameters and processes. In this paper, we present the expert model prediction of the ecological risks of pesticides (PERPEST) that overcomes these problems. It predicts the effects of a given concentration of a pesticide based on the outcome of already performed experiments using experimental ecosystems. This has the great advantage that the outcome is more realistic. The paper especially discusses how this model can be used to translate measured and predicted concentrations of pesticides into ecological risks, by taking data on measured and predicted concentrations of atrazine as an example. It is argued that this model can be of great use to evaluate the outcome of chemical monitoring programmes (e.g. performed in the light of the Water Framework Directive) and can even be used to evaluate the effects of mixtures.     

Modelling coral reef ecosystems with limited observational data

Ecosystem models represent potentially powerful tools for coral reef ecosystem managers. They can provide insight into ecosystem dynamics not achievable through alternative means allowing coral reef managers to assess the potential outcome of any given management decision. One of the main limitations in the applicability of ecosystem models is that they often require detailed empirical data and this can restrict their applicability to ecosystems that are either currently well studied or have the resources available to collect the required data. This study describes the development of a coral reef ecosystem model that can be calibrated to an ecosystem with limited empirical data. Based on the assumption that coral reef ecological structure is generic across all tropical coral reefs and that the magnitude of the interactions between ecological components is reef specific, the dynamics of the ecosystem can be replicated based on limited empirical data. The model successfully replicated the dynamics of three individual reef systems including an inshore and oceanic reef within the Great Barrier Reef and a Caribbean reef system. It highlighted the importance of understanding the specific dynamics of a given reef and that a positive management intervention in one system may result in a negative outcome for another. The model was also used to assess the importance of various interactions within coral reef ecosystems. It identified the interactions between hard corals and other non-algal benthic components as being an important (but currently understudied) facet of coral reef ecology. The development of this modelling approach provides access to ecosystem modelling tools for coral reef managers previously excluded due to a lack of resources or technical expertise.     

生态系统服务研究的问题与展望

生态系统服务的研究是当前资源经济学和生态经济学的研究热点之一。通过分析生态系统服务的概念辨析,认为从生态系统功能的定义过渡到生态系统服务定义的过程中,在关注生态系统整体性的同时忽略了生态系统要素之间的相互作用,导致生态系统服务的评估中可能存在着重复估值或者估值不全面等风险。针对目前的很多生态系统的评估对生态系统的耗损贬值和环境退化所造成的负效益的忽略,以及对人类活动的干扰和气候变化等对生态系统服务产生影响研究不足,提出在今后的研究中应该在深入理解生态系统的复杂生态学机制的基础上,结合数学模型模拟在不确定性下的各种风险损失,加强对生态系统服务的时空动态分析,重视在气候变化、经济发展、环境污染、城市化以及人类活动的过度放牧和过度开垦引起的水土流失、环境退化、荒漠化等土地利用变化的干扰时生态系统服务的变化和反馈,更进一步分析和预测生态系统服务的损益和响应研究;通过长期的试验监测揭示生物多样性和生态系统的关系,测度出土地利用和环境变化对生物多样性的影响和边际效益,及其对生态系统服务的影响的弹性值,实现生态系统服务的精确估值;关注生态系统服务对人类福利的影响,尤其重视贫困地区和生态脆弱区的生态系统服务对减小贫困的研究,建立科学的生态补偿机制,实现可持续发展。     

Evaluation of information indices as indicators of environmental stress in terrestrial soils

Information indices from Ecosystem Network Analysis (ENA) can be used to quantify the development of an ecosystem in terms of its size and organization. There are two types of indices, i.e. absolute indices that describe both the size and organization of ecosystem (Total System Throughput (TST)—system size, Ascendancy (A)—size of organized flows and Development Capacity (C)—upper limit for A, Overhead (L)—size of unorganized flows) and relative indices that describe only the organization (Average Mutual Information (AMI = A:TST), Flow Diversity (H = C:TST), Relative Overhead (RL = L:TST)).It is theorized that environmental stress impair the ecosystem development and that the effect of stress can be quantified with the ENA information indices. Here we applied ENA on a case of environmental stress in a terrestrial ecosystem, i.e. soils that have endured long-term exposure to elevated copper concentration and altered pH.The absolute indices showed an unexpected pattern of response to pollution, suggesting that ecosystems in polluted soils are more active and better organized than these in unpolluted soils. The relative indices, alternatively, responded to pollution as predicted by theory, i.e. with decrease of stress (pollution level) the level of specialization increased (increase of AMI) and losses of energy, e.g. due to respiration, decreased (decrease of Overhead). The diversity and evenness of flows showed hump-backed relationship with stress. Less polluted soils appeared to be less vulnerable to external disturbances and more efficient in processing energy (higher Relative Ascendancy (RA = A:C)) than polluted soils. The relative information indices were rigid to changes in values of assumed parameters. The relative indices, opposite to absolute indices, appeared to be useful as indicators of environmental stress on the ecosystem level.     

Quantity and quality: unifying food web and ecosystem perspectives on the role of resource subsidies in freshwaters

Although the study of resource subsidies has emerged as a key topic in both ecosystem and food web ecology, the dialogue over their role has been limited by separate approaches that emphasize either subsidy quantity or quality. Considering quantity and quality together may provide a simple, but previously unexplored, framework for identifying the mechanisms that govern the importance of subsidies for recipient food webs and ecosystems. Using a literature review of > 90 studies of open-water metabolism in lakes and streams, we show that high-flux, low-quality subsidies can drive freshwater ecosystem dynamics. Because most of these ecosystems are net heterotrophic, allochthonous inputs must subsidize respiration. Second, using a literature review of subsidy quality and use, we demonstrate that animals select for high-quality food resources in proportions greater than would be predicted based on food quantity, and regardless of allochthonous or autochthonous origin. This finding suggests that low-flux, high-quality subsidies may be selected for by animals, and in turn may disproportionately affect food web and ecosystem processes (e.g., animal production, trophic energy or organic matter flow, trophic cascades). We then synthesize and review approaches that evaluate the role of subsidies and explicitly merge ecosystem and food web perspectives by placing food web measurements in the context of ecosystem budgets, by comparing trophic and ecosystem production and fluxes, and by constructing flow food webs. These tools can and should be used to address future questions about subsidies, such as the relative importance of subsidies to different trophic levels and how subsidies may maintain or disrupt ecosystem stability and food web interactions.     

西藏中部草地及农田生态系统的退化及其机制

西藏中部农田，特别是兼具草地与林地两大功能的草地生态系统对区域生态环境具有重要的调节和控制作用。近年来，草地及农田生态系统呈现出整体退化及日趋严重的态势，并逐步成为西藏风蚀沙化、水土流失等最为严重的地区。文章在阐述退化生态系统的内在特征及其环境效应的基础上，就草地及农田生态系统退化的发生机制进行了深入分析。