海洋微生物来源的天然产物开发研究进展

综述了近年来海洋微生物来源天然产物研究的新进展,总结了该类天然产物的开发策略.通过对样品采用不同的预处理方式、不同的分离培养基以及新的培养方法,讨论如何获得海洋来源的特有微生物和增加海洋来源微生物类群的多样性.阐述了在海洋微生物天然产物的开发过程中,采用宏基因组技术及基因组测序等手段,来发现难培养或不可培养微生物中的天然产物以及处于"沉默"状态的天然产物.最后介绍了异源生物合成、组合生物合成以及核糖体工程等技术在海洋微生物天然产物开发和改造中的应用,并举例论述了海洋微生物天然产物的开发.     

太湖、巢湖沉积物中重金属污染的总量特征及其区域性差异

选取太湖、巢湖污染较为严重的区域为研究对象,采集季节性沉积物柱状样,以0.5cm的间距高精度分割样品,分析其中的Fe,Mn,Cu,Zn等重金属元素的含量,对沉积物中重金属的总量特征及季节性变化特征进行了分析,得出以下结论:太湖、巢湖沉积物中重金属的总量均呈现出Fe>Mn>Zn>Cu的特征,季节性变化幅度为Mn>Fe>Zn>Cu,重金属元素的地球化学性质对其季节性变化有很大的影响.同时,不同的区域背景差异(如元素丰度、污染状况等)导致了太湖、巢湖采样点沉积物中重金属元素季节性特征的差异.     

智能化建筑=绿色建筑

在过去的十年中,“智能化建筑”这个术语已经被广泛地用于描述新的高技术建筑物.这一术语在亚洲已经相当流行,那里有许多最大的新建筑建设项目.智能化建筑的概念自然与对环境无害的“绿色建筑物”有关.本文对Brengel技术中心作了介绍,它是由美国绿色建筑理事会(USGBC)能源和环境设计指导(LEED)绿色建筑评定体系首批认证的12个建筑物之一.     

智能化建筑=绿色建筑

在过去的十年中 ,“智能化建筑”这个术语已经被广泛地用于描述新的高技术建筑物 .这一术语在亚洲已经相当流行 ,那里有许多最大的新建筑建设项目 .智能化建筑的概念自然与对环境无害的“绿色建筑物”有关 .本文对 Brengel技术中心作了介绍 ,它是由美国绿色建筑理事会 (USGBC)能源和环境设计指导 (LEED)绿色建筑评定体系首批认证的 12个建筑物之一 .     

美国可持续的建筑服务:承包商在绿色建筑中的作用

成功的可持续建筑设计和建造过程的特点是合作的和跨科学的,然而在很多情况下,实现建设服务并未被看作是可持续的建筑项目的设计和交工的一个必要步骤.承包商常常仅仅被看作是建筑服务的经纪人,他们只是简单地遵循图纸和技术要求,并且只是通过建筑现场再循环计划对可持续的建筑工程做出贡献.宾夕法尼亚州立大学和实现优秀建筑的合作伙伴(PACE)正在联合进行关于在成功地交付高性能的可持续建筑物过程中建筑管理伙伴作用的研究,其目的是确定对可持续的建筑项目起决定性作用的过程和决策中建造服务工作的价值,和为参与可持续的设计和建筑过程的合作单位开发先进的技术.     

纳米金属氧化物模拟天然酶催化水体中酚类污染物转化的研究进展

天然酶作为一种绿色催化剂,能够介导水体中酚类污染物形成酚氧自由基中间体,随后这些活性中间体通过共价偶联机制生成大分子聚合产物.纳米金属氧化物(N-MOs)兼具纳米材料和天然酶"双重身份",有望克服天然酶稳定性差、难回收、易失活和价格昂贵等缺点,高效地催化氧化水体中酚类污染物的转化.本文概述了两种天然酶(过氧化物酶和酚氧化酶)的基本性能及其催化偶联酚类污染物转化的作用机理,系统地探讨了N-MOs的纳米特性及其模拟天然酶催化氧化底物的显色反应、作用效能和影响因素,并阐释了N-MOs作为纳米酶催化氧化酚类污染物转化的最新研究进展及其潜在的应用价值,旨在为拓展和开发新型、有效地纳米酶在环境中的应用提供新的理论基础和技术指导.     

智能化建筑=绿色建筑

在过去的十年中,“智能化建筑”这个术语已经被广泛地用于描述新的高技术建筑物.这一 术语在亚洲已经相当流行,那里有许多最大的新建筑建设项目.智能化建筑的概念自然与对环 境无害的“绿色建筑物”有关.本文对Brengel技术中心作了介绍,它是由美国绿色建筑理事 会(USGBC)能源和环境设计指导(LEED)绿色建筑评定体系首批认证的12个建筑物之一.     

黄土丘陵区4种植被类型土壤呼吸季节及年际变化

土壤碳库是陆地生态系统中的最大碳库,通过土壤呼吸向大气排放CO2是土壤碳固存的重要支出项.以黄土丘陵区4种典型植被类型(天然辽东栎林、人工刺槐林、天然侧柏林、天然灌丛)为研究对象.在各植被类型中设置20m×20 m的样方,在每个样方的四角和中心分别设立一个PVC环,测定分析3个生长季(2011、2013、2014年)林地土壤呼吸特征及其对主要环境因子的响应.结果表明,各林地生长季内土壤呼吸表现出明显的季节变化规律,前期较低,中后期达到较高水平,4种植被类型呈现大致相同的变化趋势.不同植被类型间土壤呼吸水平存在一定差异,总体表现为辽东栎林侧柏林灌丛刺槐林.3个生长季土壤呼吸速率在植被类型间的变异系数较年际的变异系数低.4种植被类型的土壤温湿度与土壤呼吸的相关关系都极显著(P0.01),但土壤呼吸速率对土壤湿度的响应更敏感,刺槐林尤为突出.用土壤温度和土壤湿度共同拟合土壤呼吸速率效果良好,可以较好地解释某种植被类型对环境条件的响应规律.综上,在黄土丘陵区,4种植被类型土壤呼吸具有明显的季节性;就年际变化来看环境因素对其影响大过植被类型间的影响;干旱半干旱地区土壤湿度对土壤呼吸的影响更显著,且土壤温度与土壤湿度共同拟合对土壤呼吸解释性更强.     

油松过氧化物酶季节变化动态

采用聚丙烯酰胺凝胶电泳技术,对华北地区14个油松种源的过氧化物酶(POD)季节变化动态进行了分析.电泳共分离出8条谱带,其中一条为油松的特征谱带.其余7条在不同生长季节均有较明显的变化,且不同种源间POD酶谱变化具有一定的差异,表明油松植物过氧化物酶具有季节性生长阶段的特异性和种源特异性.     

川西亚高山/高山森林土壤微生物对季节性冻融的响应

通过研究川西亚高山/高山森林矿质土壤层微生物群落丰度和结构在季节性冻融期间的变化,可为深入认识亚高山/高山森林冬季土壤生态过程提供理论依据.于2009年8月至2010年8月,在植物生长季节、土壤冻结阶段(包括土壤冻结期和土壤深冻期)和土壤融化阶段(包括土壤融冻期和土壤融化后期),采用变性梯度凝胶电泳(PCR-DGGE)和实时定量PCR技术同步研究不同海拔冷杉次生林(3 023 m)、天然混交林(3 298 m)和岷江冷杉原始林(3 582 m)矿质土壤层微生物类群的变化特征.结果显示,随着土壤冻结的开始,土壤细菌数量显著降低(P<0.05),而在随后的融化过程中又显著升高;土壤真菌数量具有和细菌数量相似的变化趋势,在融化阶段显著升高;土壤古菌数量在土壤冻结阶段得到升高,表现出与细菌数量相反的变化趋势.并且,Shannon-Wiener指数(H)随森林类群的变化而变化,在土壤冻结阶段,细菌H主要表现为3 582 m处<3 298 m处<3 023 m处,古菌H表现为3 298 m处<3 023 m处<3582 m处,真菌H表现为3 023 m处<3 582 m处<3 298 m处;而在土壤融化阶段3种菌落的H均表现为3 582 m处<3 023m处<3 298 m处.综上,季节性冻融期间强烈的环境变化极大地影响了土壤微生物群落的数量和结构,但不同微生物类群在不同海拔表现出一定的差异.     

Rapid,recurring, structured survey versus bioblitz for generating biodiversity data and analysis with a multispecies abundance model

A bioblitz inexpensively and quickly generates biodiversity data, but bioblitzes are often conducted with haphazard, unreplicated sampling. Results tend to be taxonomically, geographically, or temporally biased, lack metadata, and consist of lists of observed taxa that do not enable further analyses or correction for imperfect detection. A rapid, recurring, structured survey (RRSS) uses a structured sampling design and temporal and spatial replication to survey randomly selected sites on a conservation property. We participated in a loosely structured bioblitz and a subsequent RRSS at Big Canoe Creek Nature Preserve in Springville (St. Clair County), Alabama (USA) to compare observed richness derived from the 2 survey approaches. The RRSS data structure enabled us to fit models that accounted for imperfect detection to estimate abundances, occupancy probabilities, and habitat associations. The loosely structured bioblitz data could not be used in such models. We present a new integrated multispecies abundance model that we applied to avian RRSS data. Our model extension enables estimation for the community, employs data augmentation to estimate the number of undetected species, and incorporates covariates. The RRSS generated a more comprehensive and less biased list of observed taxonomic richness than the loosely structured bioblitz (e.g., 73 vs. 45 bird species and 104 vs. 63 insect families from the RRSS vs. loosely structured bioblitz, respectively). Models fit to the RRSS data identified seasonal patterns in avian community composition and allowed for estimation of habitat–occupancy relationships for insect taxa. The RRSS protocol has potential for broad transferability as a standardized, quick, and inexpensive way to inventory biodiversity and estimate ecological parameters while providing an outreach opportunity.     

Compliance with and ecosystem function of biodiversity offsets in North American and European freshwaters

Land-use change via human development is a major driver of biodiversity loss. To reduce these impacts, billions of dollars are spent on biodiversity offsets. However, studies evaluating offset project effectiveness that examine components such as the overall compliance and function of projects remain rare. We reviewed 577 offsetting projects in freshwater ecosystems that included the metrics project size, type of aquatic system (e.g., wetland and creek), offsetting measure (e.g., enhancement, restoration, and creation), and an assessment of the projects’ compliance and functional success. Project information was obtained from scientific and government databases and gray literature. Despite considerable investment in offsetting projects, crucial problems persisted. Although compliance and function were related to each other, a high level of compliance did not guarantee a high degree of function. However, large projects relative to area had better function than small projects. Function improved when projects targeted productivity or specific ecosystem features and when multiple complementary management targets were in place. Restorative measures were more likely to achieve targets than creating entirely new ecosystems. Altogether the relationships we found highlight specific ecological processes that may help improve offsetting outcomes.     

A palaeo-hydrogeological model for arsenic contamination in southern and south-east Asia

An argument is presented in which areas of natural arsenic contamination of modern groundwaters throughout Asia have a common origin. Arsenic originally accumulated in oceanic ferro-manganoan sediments of the eastern Palaeo-Tethys. This was further concentrated through oceanic crustal extinction in what later became the south-east Chinese accreted mineralised terrain. Proto-Himalayan uplift of this area created the palaeo-drainage systems of the Ganges – Brahmaputra, Irrawaddy, Mekong, and Red Rivers, with consequent headwater erosion of arsenic-rich sediments. Their downstream deposition as immature and easily redistributed Neogene sandstones, silts, and iron-rich clays has created secondary and tertiary reservoirs of adsorbed and authigenic arsenic, from which the current arsenic-rich groundwaters have evolved. Considering river basins within the above palaeo-hydrogeological framework provides a basis for assessing the risk of arsenic in groundwater basins of south and south-eastern Asia.     

Cost‐effective conservation of an endangered frog under uncertainty

How should managers choose among conservation options when resources are scarce and there is uncertainty regarding the effectiveness of actions? Well‐developed tools exist for prioritizing areas for one‐time and binary actions (e.g., protect vs. not protect), but methods for prioritizing incremental or ongoing actions (such as habitat creation and maintenance) remain uncommon. We devised an approach that combines metapopulation viability and cost‐effectiveness analyses to select among alternative conservation actions while accounting for uncertainty. In our study, cost‐effectiveness is the ratio between the benefit of an action and its economic cost, where benefit is the change in metapopulation viability. We applied the approach to the case of the endangered growling grass frog (Litoria raniformis), which is threatened by urban development. We extended a Bayesian model to predict metapopulation viability under 9 urbanization and management scenarios and incorporated the full probability distribution of possible outcomes for each scenario into the cost‐effectiveness analysis. This allowed us to discern between cost‐effective alternatives that were robust to uncertainty and those with a relatively high risk of failure. We found a relatively high risk of extinction following urbanization if the only action was reservation of core habitat; habitat creation actions performed better than enhancement actions; and cost‐effectiveness ranking changed depending on the consideration of uncertainty. Our results suggest that creation and maintenance of wetlands dedicated to L. raniformis is the only cost‐effective action likely to result in a sufficiently low risk of extinction. To our knowledge we are the first study to use Bayesian metapopulation viability analysis to explicitly incorporate parametric and demographic uncertainty into a cost‐effective evaluation of conservation actions. The approach offers guidance to decision makers aiming to achieve cost‐effective conservation under uncertainty.     

Threats to intact tropical peatlands and opportunities for their conservation

Large, intact areas of tropical peatland are highly threatened at a global scale by the expansion of commercial agriculture and other forms of economic development. Conserving peatlands on a landscape scale, with their hydrology intact, is of international conservation importance to preserve their distinctive biodiversity and ecosystem services and maintain their resilience to future environmental change. We explored threats to and opportunities for conserving remaining intact tropical peatlands; thus, we excluded peatlands of Indonesia and Malaysia, where extensive deforestation, drainage, and conversion to plantations means conservation in this region can protect only small fragments of the original ecosystem. We focused on a case study, the Pastaza‐Marañón Foreland Basin (PMFB) in Peru, which is among the largest known intact tropical peatland landscapes in the world and is representative of peatland vulnerability. Maintenance of the hydrological conditions critical for carbon storage and ecosystem function of peatlands is, in the PMFB, primarily threatened by expansion of commercial agriculture linked to new transport infrastructure that is facilitating access to remote areas. There remain opportunities in the PMFB and elsewhere to develop alternative, more sustainable land‐use practices. Although some of the peatlands in the PMFB fall within existing legally protected areas, this protection does not include the most carbon‐dense (domed pole forest) areas. New carbon‐based conservation instruments (e.g., REDD+, Green Climate Fund), developing markets for sustainable peatland products, transferring land title to local communities, and expanding protected areas offer pathways to increased protection for intact tropical peatlands in Amazonia and elsewhere, such as those in New Guinea and Central Africa which remain, for the moment, broadly beyond the frontier of commercial development.     

Human Influence and Classical Biogeographic Predictors of Rare Species Occurrence

Biogeographic theory predicts that rare species occur more often in larger, less‐isolated habitat patches and suggests that patch size and connectivity are positive predictors of patch quality for conservation. However, in areas substantially modified by humans, rare species may be relegated to the most isolated patches. We used data from plant surveys of 81 meadow patches in the Georgia Basin of Canada and the United States to show that presence of threatened and endangered plants was positively predicted for patches that were isolated on small islands surrounded by ocean and for patches that were isolated by surrounding forest. Neither patch size nor connectivity were positive predictors of rare species occurrence. Thus, in our study area, human influence, presumably due to disturbance or introduction of competitive non‐native species, appears to have overwhelmed classical predictors of rare species distribution, such that greater patch isolation appeared to favor presence of rare species. We suggest conservation planners consider the potential advantages of protecting geographically isolated patches in human‐modified landscapes because such patches may represent the only habitats in which rare species are likely to persist. Influencia Humana y Predictores Biogeográficos Clásicos de la Ocurrencia de Especies Raras     

Seasonal dynamics of macro-algae in the South Lake of Tunis

The macro-algae communities observed in the south lake of Tunis are characterized by the predominance of nitrophilous algae which are in the order of biomass importance:Ulva, Cladophora andEnteromorpha. We have noted seasonal changes of alga distribution. The wind appears to be one of the most important factors influencing this distribution. The total biomass reaches a maximum in the spring. Rapid decomposition of the biomass leads to a severe ecological imbalance, resulting in crises of anoxia and fish death. A restoration project has already started. It aims at removal of contaminated muds and the introduction of a new circulation system. The main objectives of this work were to collect information on the distribution and biomass of the phytobenthic communities as a first step in the constitution of a database for further comparison.     

Patterns and biases of climate change threats in the IUCN Red List

International Union for Conservation of Nature (IUCN) Red List assessments rely on published data and expert inputs, and biases can be introduced where underlying definitions and concepts are ambiguous. Consideration of climate change threat is no exception, and recently numerous approaches to assessing the threat of climate change to species have been developed. We explored IUCN Red List assessments of amphibians and birds to determine whether species listed as threatened by climate change display distinct patterns in terms of habitat occupied and additional nonclimatic threats faced. We compared IUCN Red List data with a published data set of species’ biological and ecological traits believed to infer high vulnerability to climate change and determined whether distributions of climate change‐threatened species on the IUCN Red List concur with those of climate change‐threatened species identified with the trait‐based approach and whether species possessing these traits are more likely to have climate change listed as a threat on the IUCN Red List. Species in some ecosystems (e.g., grassland, shrubland) and subject to particular threats (e.g., invasive species) were more likely to have climate change as a listed threat. Geographical patterns of climate change‐threatened amphibians and birds on the IUCN Red List were incongruent with patterns of global species richness and patterns identified using trait‐based approaches. Certain traits were linked to increases or decreases in the likelihood of a species being threatened by climate change. Broad temperature tolerance of a species was consistently related to an increased likelihood of climate change threat, indicating counterintuitive relationships in IUCN assessments. To improve the robustness of species assessments of the vulnerability or extinction risk associated with climate change, we suggest IUCN adopt a more cohesive approach whereby specific traits highlighted by our results are considered in Red List assessments. To achieve this and to strengthen the climate change‐vulnerability assessments approach, it is necessary to identify and implement logical avenues for further research into traits that make species vulnerable to climate change (including population‐level threats).     

Parasitic wasps orient to green leaf volatiles

Summary Undamaged plants emit low levels of green leaf volatiles (GLVs), while caterpillar-damaged and artificially damaged plants emit relatively higher levels of certain GLVs. Female braconid parasitoids,Microplitis croceipes, oriented to both damaged plants and to individual GLVs in no-choice tests in a wind tunnel, but seldom oriented to undamaged plants. Female ichneumonid parasitoids,Netelia heroica, also oriented to individual GLVs in a wind tunnel. Males of both wasp species failed to orient to the GLVs. These data show that leaf-feeding caterpillars can cause the release of GLVs, and that parasitic wasps can respond to these odors by flying upwind (chemoanemotactic response), which brings the wasps to their caterpillar hosts. This supports the hypothesis that plants communicate with members of the third trophic level,i.e., plants under herbivore attack emit chemical signals that guide natural enemies of herbivores to sites of plant damage. In this interaction, the GLVs serve as tritrophic plant-to-parasitoid synomones. That parasitoids from two different wasp families oriented to GLVs suggests that the response may be widespread among the Hymenoptera.Mention of a commercial or proprietary product does not constitute an endorsement by the U.S. Department of Agriculture