The plaza and the pendulum: two concepts of ecological science

This essay explores two strategies of inquiryin ecological science. Ecologists may regardthe sites they study either as contingentcollections of plants and animals, therelations of which are place-specific andidiosyncratic, or as structured systems andcommunites that are governed by general rules,forces, or principles. Ecologists who take thefirst approach rely on observation, induction,and experiment – a case-study or historicalmethod – to determine the causes of particularevents. Ecologists who take the secondapproach, seeking to explain by inferringevents from general patterns or principles,confront four conceptual obstacles which thisessay describes. Theory in ecology must (1)define and classify the object it studies,e.g., the ecosystem, and thus determine theconditions under which it remains the ``same'system through time and change. Ecologistsmust (2) find ways to reject as well as tocreate mathematical models of the ecosystem,possibly by (3) identifying efficient causes ofecosystem organization or design. Finally,ecologists will (4) show ecological theory canhelp solve environmental problems both inpristine and in human-dominated systems. Afailure to solve – or even to address – theseobstacles suggests that theoretical ecology maybecome a formal science that studies themathematical consequences of assumptionswithout regard to the relation of theseassumptions to the world.     

Is there a general theory of community ecology?

Community ecology entered the 1970s with the belief that niche theory would supply a general theory of community structure. The lack of wide-spread empirical support for niche theory led to a focus on models specific to classes of communities such as lakes, intertidal communities, and forests. Today, the needs of conservation biology for metrics of “ecological health” that can be applied across types of communities prompts a renewed interest in the possibility of general theory for community ecology. Disputes about the existence of general patterns in community structure trace at least to the 1920s and continue today almost unchanged in concept, although now expressed through mathematical modeling. Yet, a new framework emerged in the 1980s from findings that community composition and structure depend as much on the processes that bring species to the boundaries of a community as by processes internal to a community, such as species interactions and co-evolution. This perspective, termed “supply-side ecology”, argued that community ecology was to be viewed as an “organic earth science” more than as a biological science. The absence of a general theory of the earth would then imply a corresponding absence of any general theory for the communities on the earth, and imply that the logical structure of theoretical community ecology would consist of an atlas of models special to place and geologic time. Nonetheless, a general theory of community ecology is possible similar in form to the general theory for evolution if the processes that bring species to the boundary of a community are analogized to mutation, and the processes that act on the species that arrive at a community are analogized to selection. All communities then share some version of this common narrative, permitting general theorems to be developed pertaining to all ecological communities. Still, the desirability of a general theory of community ecology is debatable because the existence of a general theory suppresses diversity of thought even as it allows generalizations to be derived. The pros and cons of a general theory need further discussion.     

在微生物生态学课堂教学中落实生态文明教育

大学生是推动生态文明建设的重要支撑力量,落实大学生生态文明教育是建设生态文明社会的重要内容。微生物生态学是一门与人类活动密切相关的学科。本文通过结合课程知识点、改革教学方法、关注日常课堂生活等方面,介绍如何在微生物生态学课堂教学过程中落实生态文明教育。在传授专业知识的同时,增强大学生节约意识、环保意识、生态意识,引导大学生践行生态价值观,促进高校生态文明发展。同时,为其他相关课程教学落实生态文明教育提供借鉴与参考。     

区域生态建设与景观生态学的使命

区域和景观尺度上的生态建设是指一定地域、跨生态系统、适用于特定景观类型的生态建设,即实行科学的生态系统管理和优化环境的建设工程．近年来国家实施了一系列重大的生态工程项目,如天然林保护工程、部分地区退耕还林还草、内陆河流域的生态调水等,取得了显著的效果．加强区域生态建设,维护国土安全已成为国家的战略需求．依据不同类型区的特点应实行不同的生态建设战略,如生态敏感区、脆弱区和高人口密度的生态压力区,可分别实施以生态安全保障、生态负荷调整和生态秩序重建为重点的生态建设战略,调控人类活动,实行有序开发,统筹人与自然的和谐发展．面对转型期的国家需求,我国景观生态学的发展迎来了挑战与机遇并存的重要契机．研究的关键议题包括：景观生态安全格局;土地利用与生态过程;人类活动胁迫下的景观变化;区域开发人类活动生态影响的定量评价;区域生态安全评价与预警;景观生态建设的模式设计与优化组合．     

But is it progress? On the alleged advances of conservation biology over ecology

As conservation biology has developed as a distinct discipline from ecology, conservation guidelines based on ecological theory have been largely cast aside in favor of theory-independent decision procedures for designing conservation reserves. I argue that this transition has failed to advance the field toward its aim of preserving biodiversity. The abandonment of island biogeography theory in favor of complementarity-based algorithms is a case in point. In what follows, I consider the four central objections raised against island biogeographic conservation guidelines, arguing that they fail to undermine the credibility of this framework as a conservation tool. At best, these objections call for a more careful application of this framework to conservation problems, not its wholesale abandonment. At the same time, complementarily-based algorithms are biased in favor of networks of small reserves containing non-overlapping species. These conditions threaten to promote inbreeding depression, genetic drift and other factors that increase a population’s risk of extinction. Therefore, recent developments in the field of conservation biology have arguably not contributed to its ultimate aim of preserving the maximum amount of biodiversity in the long run.

C.D. Darlington and the British and American reaction to Lysenko and the Soviet conception of science

The Anglo-American reaction to the Lysenkoaffair has been treated primarily either fromthe point of view of the political Right orLeft, or as a consequence of post-WWIIinternational relations. None of the accountshave considered the central role of the Britishcytogeneticist and evolutionist C.D.Darlington. This article considers Darlington'srole, and illustrates how, through an analysisof his divergent reaction, it becomes possibleto see the response to Lysenko as a reflectionof internal scientific and political debatesconcerning the planning, funding, utility, andfreedom of science in post-war Britain.     

The ecological reference framework for Québec: a useful tool for forest sites evaluation

Quebec ecologists have divised, for more than 25 years, an integrated landform-soil—vegetation approach to landscape typology and mapping. Basic concepts and principles of this approach are briefly described and illustrated. In spite of the huge areas already mapped, attempts to integrate such an information in the forestry practice have thus far proven inconclusive.     

生态学的发展阶段及其特点

生态学的发展阶段及其特点吴兆录（云南大学生态学与地植物学研究所,昆明６５００９１）Ｄｅｖｅｌｏｐｍｅｎｔｓｔａｇｅｓｏｆｅｃｏｌｏｇｙａｎｄｔｈｅｉｒｃｈａｒａｃｔｅｒｉｓｔｉｃｓ．￥ＷｕＺｈａｏｌｕ（ＩｎｓｔｉｔｕｔｅｏｆＥｃｏｌｏｇｙａｎｄＧｅｏ...     

Toward a more trait-centered approach to diffuse (co)evolution

How species evolve depends on the communities in which they are embedded. Here, we briefly review the ideas underlying concepts of diffuse coevolution, evolution, and selection. We discuss criteria to identify when evolution will be diffuse. We advocate a more explicitly trait-oriented approach to diffuse (co)evolution, and discuss how considering effects of interacting species on fitness alone tells us little about evolution. We endorse the view that diffuse evolution occurs whenever the response to selection by one interacting species on a given trait is altered by the presence of a second interacting species. Building on the work of others, we clarify and expand the criteria for diffuse evolution and present a simple experimental design that will allow the detection of diffuse selection. We argue that a greater focus on selection on specific traits and the evolutionary response to that selection will improve our conceptual understanding of how communities affect the evolution of species embedded within them.     

Linking ecological and social systems in cities: urban planning in Finland as a case

The loss of urban green space as a result of urbanization threatens the overall biodiversity of urban areas, and prompts us to consider the importance of existing urban nature more carefully. Because urban ecological systems are in intense interaction with human-social systems, it is fruitful to create an interdisciplinary research and planning framework to ensure the maintenance of biodiversity in urban areas. For this purpose, we adapted a suitable theoretical and conceptual scheme for the setting of Finnish urban development, which provides an example of a situation where a lot of nature has so far remained inside and around urban area. The adapted scheme focuses on the land use change as a result of urban land use planning and development, and may provide a way to address the important variables and feedback mechanisms between information flowing from ecological systems and drivers from the social system. Furthermore, we outlined a more specific framework around the Finnish urban detailed planning process in order to study the interactions between these systems further. After addressing ecology-oriented questions of quantity, quality and needs of urban nature, and human-oriented drivers, such as flow and incorporation of information, knowledge, values and institutions, we identified several challenges in integrating the components of ecological and social systems. Creating common conceptual ground for different actors and disciplines, improving communication in the process, matching contradictory values and perceptions, and improving stakeholder participation would be in the best interest of nature and people of urban areas.     

The ecology of conception and pregnancy failure in wild baboons

Environmental conditions are a key factor mediating reproductivesuccess or failure. Consequently, many mammalian taxa have breedingseasons that coordinate critical reproductive stages with optimalenvironmental conditions. However, in contrast with most mammals,baboons (Papio cynocephalus) of Kenya reproduce throughout theyear. Here we depart from the typical approach of evaluatingseasonal effects on reproduction and engage in a more fine-grainedanalysis of the actual ecological conditions leading up to reproductionfor females. Our aim was to determine how environmental conditions,in combination with social and demographic factors, might mediatebaboon reproduction. The data set includes all female reproductivecycles from multiple baboon groups in the Amboseli basin between1976 and 2004. Results indicate that after periods of droughtor extreme heat, females were significantly less likely to cyclethan expected. If females did cycle after these conditions,they were less likely to conceive; and if they did conceiveafter drought (heat effects were nonsignificant), they wereless likely to have a successful pregnancy. Age also significantlypredicted conceptive failure; conceptive probability was lowestamong the youngest and oldest cycling females. There was alsoa trend for high ambient temperatures to contribute to fetalloss during the first trimester but not other trimesters. Finally,group size and drought conditions interacted in their effectson the probability of conception. Although females in all groupshad equal conception probabilities during optimal conditions,females in large groups were less likely than those in smallgroups to conceive during periods of drought. These resultsindicate that in a highly variable environment, baboon reproductivesuccess is mediated by the interaction between proximate ecologicalconditions and individual demographic factors.     

张家口市坝上地区生态足迹初步研究

1　引　　言张家口市坝上地区是我国重要的农牧交错区 .长期以来在农牧交错区 ,由于人类对自然资源的强度利用 ,已经超过了生态系统的承载力 ,生态退化非常严重 .定量地计算农牧交错区生态系统承载力 ,确定其阈值 ,是生态保护和建设急需解决的问题 .加拿大生态经济学家ＷｉｌｌｉａｎＲｅｅｓ等提出的生态足迹的概念以及生态足迹、生态承载力的计算方法[2～ 4 ] ,为这一问题的解决 ,指出了简洁的思路和方法 .国内已介绍和进行区域研究[1,5,6 ] .本文应用该方法 ,以张家口市坝上地区为例 ,研究了农牧交错区的生态承载力阈值和人口容限值 ,提…     

论转基因林木的潜在生态风险性

基因工程技术为加快林木遗传改良进程开辟了一条崭新的途径．由于林木栽培环境复杂、生产周期长、经营管理粗放,且主要为风媒传粉植物等原因,与集约化程度较高的农作物相比,转基因林木环境释放及推广的潜在生态风险性更大．如转基因林木大量种植可加速该树种遗传多样性水平降低,导致遗传脆弱性;转基因林木的长期持续强选择压力作用导致害虫、病菌协同进化;外源基因逃逸有可能使非转基因植物的生态适合度增强或降低,进而影响到自然界的物种多样性等。     

甘肃省河西绿洲农业区生态足迹动态研究

研究了甘肃省河西绿洲农业区1949～2000年生态足迹的动态变化、区域可持续发展程度及未来可持续发展的趋势．结果表明,河西全区的人均生态足迹在1949～2000年呈递增趋势,从0．426hm^2增加到2．158hm^2。1949～1970年平均为0．693hm^2,1975～1980年平均为1．029hm^2,1985～2000年平均为2．288hm^2：人均生态承载力由1949年的0．550hm^2增加到2000年的1．762hm^2,与人均生态足迹相比,增幅较小,增速亦慢．1949～1970年平均为0．782hm^2,1975～2000年平均为1．715hm^2;1949—1975年为生态盈余阶段,平均盈余为0．088hm^2,1980年首次出现赤字,1985年又恢复为盈余,到1991年后持续出现生态赤字。且赤字程度为加速度负增长,1991～2000年平均赤字为0．258hm^2．河西全区的区域经济正朝远离可持续的方向发展,且已处于不可持续状态．     

Toward a more holistic ecology,and science: the contribution of H.T. Odum

Conclusion For the abovementioned reasons, and with all due respect to the scholarship of Mansson and McGlade, who display a deep knowledge of thermodynamics and ecology, I cannot agree that Odum's use of energy concepts is wholly discredited. Refinements from microscopic thermodynamics may not have been faithfully carried along in his work, but does ecology really need these? Remember — the meal test.Having tussled with ecological complexity myself, I stand in awe of this man who has faced up to what most ecologists today are trying to deny — intractable, crushing, defeating complexity. If Odum has provided some of the first shaky stepping stones across this gulf, that's enough.I can finish by quoting from ny Festschrift paper again:It is often said of scientists who make unusual contributions against the grain of their disciplines that they are ahead of their time. In H.T. Odum's case, with maximum power, energy-circuit diagrams, emergy, transformity, and energy value the linchpins of a whole new theory of ecology, and paradigm within systems ecology, this can certainly be stated without hesitation. But in this instance, it is also possible to turn the observation around and suggest that ecology-as-science is behind its time, lagging the curve of need foreseen decades ago by a more pragmatic ecology-as-ethic and-concern. The growing man-and-environment tension, fostered by so-far unabatable growth of populations, technologies and economies, demands a science that incises complexity, finds the essence of systemness, and produces quantitative methods capable of moulding this essence to meet the imperatives of the new environmentalism. H.T. Odum has not, perhaps, provided a definitive theory to do this; no one could right now. But, he has given us an intriguing mix of science, art and religion that stands as one of the singular legacies of 20th-century ecology, pointing the way toward a new ecology of complexity that must, I think from need, fully arise in the 21st century. His time has been behind him.     

The ecological rationality of helping others: Potential helpers integrate cues of recipients' need and willingness to sacrifice

Why do humans help others? Many theories focus on dimensions like kinship or reciprocity. On their surface, these theories seem unable to explain help directed at fleeting strangers. In response to this puzzle, researchers have proposed that the mind has ecologically rational systems for providing aid. These systems respond to cues that predicted adaptive behavior during human evolution, regardless of whether such cues continue to be predictive in modern environments. In three studies, we test for two cues that might predict whether a potential benefactor will help a potential recipient: the need of the recipient and the extent to which the recipient is willing to sacrifice for the benefactor. Both cues, in ancestral environments, have the potential to predict whether a long-term relationship might be established. Consistent with past research, we find that both cues matter: Needy people and people willing to sacrifice are helped more. However, the cues are not merely additive: In some cases, the cue of need is ignored and only willingness to sacrifice is used. We discuss these results in terms of recent evolutionary theories of emotions.     

新疆生态足迹与环境压力的时空分异

提高生态现代化总体水平是改善区域生态环境承载力的核心和关键。利用生态环境质量指数和生态现代化指数(EM I)对我国西部生态环境脆弱区的新疆维吾尔自治区生态足迹和环境压力的变动态势进行了系统分析。结果表明:2004年新疆生态现代化指数在全国排名为27位,仍然为我国生态现代化水平落后的地区之一。1980—2005年,新疆综合现代化水平远低于高收入国家、世界平均水平和中等发达国家。1998年新疆人均生态足迹由25957hm2增加到2007年的40551hm2,人均生态承载力由3.1270hm2减少到2.8266 hm2。区域环境水平呈下降趋势。资源转化率、生态保护指数呈明显上升态势。环境治理指数呈剧烈变动,1996-2003年呈"N"型变动态势,区域生态脆弱性没有明显逆转。     

中国2002年省域生态足迹分析

采用中国实际单产法计算和分析了2002年中国各省市生态足迹及其构成,发现各省市生态足迹及其构成差异较大,其中人均耕地足迹由陕西的0.078 hm²增加到北京的0.126 hm²,人均草地足迹由江西的0.020 hm²增加到西藏的0.372 hm²,人均林地足迹由贵州的0.020 hm²增加到北京的0.209 hm²,人均水域足迹由西藏的0.001 hm²增加到上海的0.011 hm²,人均建筑用地足迹由贵州的0.013 hm²增加到内蒙古的0.054 hm²,人均化石能源足迹由广西的0.251 hm²增加到山西的2.854 hm².东部、南部省市各地类多处于生态赤字状态,北部、西部省市各地类多处于生态盈余状态.从生态足迹、人均GDP和万元GDP足迹的相互关系来看,各地区存在较大的差异,如人均生态足迹为1 hm²·cap^-1的省份包括福建、河南、四川、安徽、云南、陕西和贵州,其人均GDP由福建的1.35万元降至贵州的0.3万元,而万元GDP足迹却由福建的0.74 hm²增至贵州的3.51hm².因此,要缓解中国资源短缺与经济发展之间的矛盾,要首先从人均生态足迹大、经济发展落后、万元GDP足迹高的省市入手,改变其经济增长方式和产业结构,使经济的发展对资源的依赖性逐渐降低,提高资源利用效率,提高其足迹经济产出率,大力发展经济,实现生态、资源、经济的可持续发展.