Persistence of Forest Birds in the Costa Rican Agricultural Countryside

Abstract:  Understanding the persistence mechanisms of tropical forest species in human-dominated landscapes is a fundamental challenge of tropical ecology and conservation. Many species, including more than half of Costa Rica's native land birds, use mostly deforested agricultural countryside, but how they do so is poorly known. Do they commute regularly to forest or can some species survive in this human-dominated landscape year-round? Using radiotelemetry, we detailed the habitat use, movement, foraging, and nesting patterns of three bird species, Catharus aurantiirostris , Tangara icterocephala , and Turdus assimilis , by obtaining 8101 locations from 156 individuals. We chose forest birds that varied in their vulnerability to deforestation and were representative of the species found both in forest and human-dominated landscapes. Our study species did not commute from extensive forest; rather, they fed and bred in the agricultural countryside. Nevertheless, T. icterocephala and T. assimilis , which are more habitat sensitive, were highly dependent on the remaining trees. Although trees constituted only 11% of land cover, these birds spent 69% to 85% of their time in them. Breeding success of C. aurantiirostris and T. icterocephala in deforested habitats was not different than in forest remnants, where T. assimilis experienced reduced breeding success. Although this suggests an ecological trap for T. assimilis , higher fledgling survival in forest remnants may make up for lower productivity. Tropical countryside has high potential conservation value, which can be enhanced with even modest increases in tree cover. Our findings have applicability to many human-dominated tropical areas that have the potential to conserve substantial biodiversity if appropriate restoration measures are taken.     

Beyond identity crisis: The challenge of recontextualizing ecosystem delimitation

In a series of papers, three important system ecologists, Bernard C. Patten, Sven E. Jorgensen and Milan Straškraba attempt to revise the old ecosystem field and construct a new systems ecology. Inevitably, their attempt is faced with some of the same problems that led the field to decline. The indefiniteness of ecosystem boundaries is one of them, maybe the most important. Systems’ ecology failure to define ecosystem boundaries was considered a significant obstacle for the conceptualization of the ecosystem as a valid organizing unit of nature and resulted in a disciplinary identity crisis. To surmount this crisis, the authors introduce into the field innovative ideas which have their origin in the so-called postmodern network theories. These ideas reinforce the concept of environment and allow for a relative conception of space, which might have beneficial effects in delimiting ecosystems. However, the problem-solving potential of these ideas is not activated because the authors remain stitched to the Odumian mode of ecosystem thinking and avoid recontextualizing the old building blocks.     

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.     

土壤微生物生态学研究方法进展

土壤微生物研究方法经历了微生物纯培养、土壤酶活性(BIOLOG微平板分析)、微生物库(如微生物生物量)和流(C和N循环)、微生物生物标记物(FAMEs)、微生物分子生物学技术(从土壤中提取DNA,进行PCR-DGGE、PCR-SSCP、RLFP分析等),揭示了土壤微生物群落丰富的多样性和生态功能;现代生物技术和传统微生物研究方法的配合将为土壤微生物学研究提供较好的前景。     

Integrating the Metapopulation and Habitat Paradigms for Understanding Broad-Scale Declines of Species

Abstract:  Caughley (1994) argued that researchers working on threatened populations tended to follow the "small population paradigm" or the "declining population paradigm," and that greater integration of these paradigms was needed. Here I suggest that two related paradigms exist at the broader spatial scale, namely the metapopulation paradigm and habitat paradigm, and that these two paradigms also need to be integrated if we are to provide sound management advice. This integration is not trivial, and I outline five problems that need to be addressed: (1) habitat variables may not measure habitat quality, so site-specific data on vital rates are needed to resolve the effects of habitat quality and metapopulation dynamics; (2) measurements of vital rates may be confounded by movements; (3) vital rates may be density dependent; (4) vital rates may be affected by genotype; and (5) vital rates cannot be measured in unoccupied patches. I reviewed papers published in Conservation Biology from 1994 to 2003 and found 41 studies that analyzed data from 10 or more sites to understand the factors limiting species' distributions. Five of the analyses presented were purely within the metapopulation paradigm, 14 were purely within the habitat paradigm, 17 involved elements of both paradigms, and 7 were theoretically ambiguous (2 papers presented 2 distinct analyses and were counted twice). This suggests that many researchers appreciate the need to integrate the paradigms. Only one study, however, used data on vital rates to resolve the effects of habitat quality and metapopulation dynamics (problem 1), and this study did not address problems 2–5. I conclude that more intensive research incorporating site-specific data on vital rates and movement is needed to complement the numerous analyses of distributional data being produced.     

A Landscape Approach to Biodiversity Conservation of Sacred Groves in the Western Ghats of India

Abstract:  Although sacred groves are important for conservation in India, the landscape that surrounds them has a vital influence on biodiversity within them. Research has focused on tree diversity inside these forest patches. In a coffee-growing region of the Western Ghats, however, landscape outside sacred groves is also tree covered because planters have retained native trees to provide shade for coffee plants. We examined the diversity of trees, birds, and macrofungi at 58 sites—10 forest-reserve sites, 25 sacred groves, and 23 coffee plantations— in Kodagu district. We measured landscape composition and configuration around each site with a geographic information system. To identify factors associated with diversity we constructed multivariate models by using a decision-tree technique. The conventional measures of landscape fragmentation such as patch size did not influence species richness. Distance of sacred groves from the forest reserve had a weak influence. The measures of landscape structure (e.g., tree cover in the surroundings) and stand structure (e.g., variability in canopy height) contributed to the variation in species richness explained by multivariate models. We suggest that biodiversity present within sacred groves has been influenced by native tree cover in the surrounding landscape. To conserve this biodiversity the integrity of the tree-covered landscape matrix will need to be conserved.     

生态学及其相关学科SCI收录期刊介绍

将SCI收录的76种及中国进入科学引文索引和科学引文索引扩展版的生态学类日核心期刊进行了全面的揭示，包括英文刊名、汉译刊名、山版周期、原版刊号、最新影响因子、国际标准刊号、出版地、出版者、联系地址、最新期刊刚址，期刊描述等全方位的期刊信息。期刊描述内容包括：期刊的创刊年以及期刊的发展。期刊主要内容及使用的话言。网站可免费获取的该刊目次和文摘及全文信息等。     

试论矿山环评中的生态恢复评价问题

矿山生态恢复是矿山环保对策中的一项技术较强的措施之一，它既有防治水土流失的功能，又有降解有毒污染的功能，并能产生较好的经济效益。但没有科学依据而盲目进行生态恢复，就有可能对环境和人类带来风险，为减少风险，在矿山开发前的环境影响评价中，就应对生态恢复这一措施进行评价，提出合理的恢复模式，为决策部门提供科学依据。     

植物根圈污染生态研究进展

阐述了植物根圈的概念 ,根圈三大结构主成份是 (1)植物根系 ,(2 )微生物 ,(3)土壤或水等 ,并从它们的相互关系出发讨论了国内外有关根圈污染生态的研究情况 ,同时提出了根圈污染生态的研究前景和意义。     

乡村景观规划的发展历史及其在我国的发展前景

介绍了国内外乡村景观规划的发展历史 ,阐述了乡村景观规划的内容和特点 ,并简要分析了我国开展乡村景观规划的基础研究和应用的发展趋势 ,指出了应继续完善系统性的理论和方法论上的探讨 ,并对一些重点区域进一步开展典型研究和实践应用 ,以此作为今后研究发展的重点领域。     

青海高原土壤拮抗性放线菌的生态分布

采用琼脂块法测定了分离自青海高原不同生态环境下的 1 007株代表性放线菌的拮抗性.结果表明:①供试菌中对大肠杆菌、金黄色葡萄球菌、假丝酵母、青霉、辣椒疫霉、西瓜枯萎菌、棉花枯萎菌及黄瓜枯萎菌有拮抗性的放线菌占供试菌总数的比率分别为 9. 1%、27. 2%、2. 1%、2. 6%、13. 8%、10. 1%、7. 1%及 7. 4%;在青海高原(西部)土壤的拮抗性放线菌中,抗细菌放线菌多于抗真菌放线菌,抗G+细菌的放线菌多于抗G-细菌放线菌,抗丝状真菌放线菌多于抗单细胞真菌放线菌.②耕作土壤中,拮抗性放线菌株数占放线菌总株数的百分率 (拮抗菌百分率 )是自然土壤的3. 5倍,且耕作土壤拮抗菌百分率按菜地(71. 7% ) >粮田(40. 6% ) >绿肥地(32. 8% ) >果园(25. 0% )的顺序排列.旱地土壤拮抗菌百分率明显高于水地.③不同类型土壤拮抗菌百分率均不同,且不同类型土壤拮抗菌百分率按黑钙土>栗钙土>灰钙土>砂土的顺序排列.④拮抗性放线菌的数量、拮抗菌百分率与土壤有机质、全氮、碱解氮、全磷及磷酸酶活性有关.其中有机质和全氮与拮抗性放线菌株数和拮抗菌百分率的相关性达极显著水平 (P<0. 01).抗细菌与抗真菌拮抗性放线菌的出现频率与土壤有机质、全氮及放线菌总数量的相关性分别达到了极显著(P<0. 01)与显著水平(P<0. 05),且土     

敦煌地区生态问题的地质学探析

敦煌地区严重的生态环境退化问题,其根源在于对其产生的原因及其演变过程没有科学、统一的认识.尽管近年来政府及有关部门投入了大量的人力物力,采取了一些措施,做了一些研究,但效果并不明显,甚至有人提出将之与古楼兰衰退相提并论.该文认为,敦煌地区生态退化及其演变,无论是地下水位的下降、绿洲与湿地的萎缩等,都是地质科学领域的问题,需要运用地质学思维分析探讨.研究改善敦煌的生态环境退化和治理措施,必须从环境地质、生态地质学的理论和方法去解决.图1,参13.     

岳阳市城市扩张期环境生态可持续发展

在已有可持续发展理论的基础上，以岳阳市环境生态为研究对象，利用主成分分析法、层次分析法（AHP）和德尔斐的方法计算和分析在城市化过程中环境生态变化情况，论述了这一过程中环境生态存在的问题和产生的原因，对目前小城市向中等城市转变过程中避免和解决环境生态问题提供了例证。     

Sympatric species of threespine stickleback differ in their performance in a spatial learning task

Increasing evidence suggests that cognitive function is under selection in diverse taxa and that this results in different cognitive abilities in taxa experiencing different selective environments. For example, species inhabiting spatially complex environments might be expected to have good spatial learning ability. We investigated whether local habitat conditions influence learning by comparing the performance of two recently diverged species of threespine stickleback (Gasterosteus aculeatus complex) in a spatial learning task. The two species reside sympatrically in several lakes. Benthics occupy the spatially structured vegetated littoral zone, whereas limnetics occupy the spatially homogenous open-water pelagic zone. We trained fish to locate a hidden reward in a T-maze and asked whether they did so by learning a body-centred pattern of movement (turn left or right) or by using plant landmarks. Both benthics and limnetics used turn and landmark cues, but benthics learnt the task almost twice as quickly as limnetics. This difference is consistent with the hypothesis that benthic and limnetic sticklebacks are equipped with spatial learning abilities well suited to the spatial complexity of their littoral and pelagic habitats. Our findings add to the understanding of the evolution of learning.     

中国乡村城市化过程中的景观生态学问题与对策研究

城市和乡村的发展共同构成了社会-经济-自然复合生态系统的可持续发展,然而长期以来,重城市轻乡村的发展思想导致了城乡二元结构矛盾不断尖锐。随着经济的高速发展和加入WTO后的国际化冲击,未来的10~20年间,中国将进入一个乡村城市化快速发展的时期,这将使得中国本来紧张的人地关系变得更加严重,资源消耗与环境污染问题日益突出,乡村发展将面临更大的挑战,同时也将是中国乡村发展的重要契机。本文依据景观生态学原理与方法,通过研究乡村城市化进程中乡村景观的组合、结构、功能以及变化中存在的问题,提出了城乡协调、全盘布局和保留自身特色等相应的生态规划治理措施和对策,尽可能使乡村景观格局呈现多样性、异质性,并在功能上表现出稳定性和连续性,最终实现城乡景观和谐发展的局面。     

制度-技术-资源协同影响生态经济的效果分析

生态经济是在生态系统承载能力范围内,运用系统工程方法和生态经济学原理改变生产和消费方式,挖掘资源的潜力,建设体制合理与社会和谐环境的经济形态。生态经济的以资源为基础,以政策与制度为导向,以技术创新为支撑,是制度、技术、资源等重要影响变量协同作用的结果,制度变迁、技术创新、资源利用三者共同作用于生态经济运行过程都呈现出了典型的非线性特征;将制度、技术、资源分别视为生态经济系统的高层、中层和低层子系统,以逻辑斯蒂（Logistic）曲线为基础,建构了生态经济发展的非线性动力学模型;最后以系统论的观点分析了制度、技术、资源与生态经济发展、科学发展观贯彻、和谐社会构建之间的互动关系。     

洞庭湖区生态环境退化状况及其原因分析

洞庭湖居湖南省东北隅,长江荆江段南岸。湖泊形状呈近似“U”字形,岳阳站水位33.50 m时(黄海基面),湖长143.00 km,最大湖宽30.00 km,平均湖宽17.01 km,湖泊面积2625 km2;最大水深23.5 m,平均水深6.39 m,蓄水量167?08 m3。因入湖泥沙长期淤积、高洲围垦、并垸合流等自然因素和人类活动的共同影响,自清代末期以来,湖泊形态演变剧烈,湖盆抬高,入湖河流三角洲快速发育,湖面南移而缩小;现湖体已明显演变为西洞庭湖、南洞庭湖和东洞庭湖首尾相接三个部分,具有“高水湖相,低水河相”的典型特征。洞庭湖区不但是我国受洪水威胁最严重的地区之一,而且生态退化和环境问题也十分突出,一直受到国家的高度重视。文章在大量调查的基础上,对洞庭湖及其湖区的生态环境退化状况、产生原因和可能带来的负面影响等方面进行了初步分析。     

我国山地城镇的景观生态学探讨

应用景观生态学的理论，与平原城镇相比较，分析了山地条件下的山地城镇的景观生态特性：景观自然生境要素多，廊道体系不发达，景观要素布局松散，生态系统抗干扰能力差。按照地形条件和结构形态对山地城镇的景观结构类型进行了详细分类，总结了山地城镇的主要生态问题，为山地城镇的景观规划与设计提供参考。     

昆山市城市森林生态建设规划

通过对昆山市森林生态现状及城市建设中存在问题的分析,结合国际城市生态发展的趋势,提出了由三环、两区、一链、四横、三纵、四大片为基本骨架的昆山市森林生态建设总体布局,为昆山市今后的森林生态建设提出思路和对策。     

Callyspongia samarensis (Porifera) extracts exhibit anticancer activity and induce bleaching in Porites cylindrica (Scleractinia)

Marine sponges can produce allelopathic compounds with specific roles in the competition for benthic space. Here we demonstrate that extracts from Callyspongia samarensis (Phylum Porifera) accelerate bleaching in Porites cylindrica (Phylum Cnidaria, Order Scleractinia) and exhibit in vitro anticancer activity. A column chromatography fraction and HPLC fraction, purified from the crude methanol extract of C. samarensis, were incorporated into agar gel cubes at natural concentrations and tested on P. cylindrica corals in a laboratory assay. Statistical analysis of percent bleached area and maximum quantum yield showed that a significant difference existed between P. cylindrica nubbins that were exposed to C. samarensis extracts versus the control group. This suggests that C. samarensis contains allelopathic compounds that can cause bleaching in P. cylindrica, possibly leading to tissue necrosis and death. Furthermore, the aforementioned HPLC fraction exhibited significant growth inhibition of the HCT-116 (human colon cancer) cell line. Understanding the strategies by which sponges exert dominance over other organisms is important because it provides information about the ecological roles of sponge allelopathy and can result in the discovery of compounds with biomedical potential.