山东南四湖湿地生物多样性及保护措施

南四湖湿地由湖泊、沼泽湿地和人工湿地构成,生物多样性十分丰富。其湿地生态系统具有生境脆弱性、物种多样性、生物稀有性、生态自然性等特点,是我国华北平原最大的具有良好湿地植被的天然湿地生态系统,同时也是众多候鸟的越冬地、繁殖区及迁徙必经的中转站。分析了湿地生物多样性现状及保护中存在的主要问题,提出了相应的湿地保护措施。     

Stay with the flow: How macroinvertebrate communities recover during the rewetting phase in Alpine streams affected by an exceptional drought

Droughts are affecting an increasing number of lotic ecosystems worldwide due to the combined effects of climatic and anthropogenic pressures. Unlike naturally intermittent rivers, where the drying phase is a part of the annual flow regime, water scarcity in Alpine rivers represents a relatively recent phenomenon and, therefore, a major threat for the biodiversity of these lotic ecosystems. However, Alpine stream community response to drought is still poorly investigated. Here, we assess the recovery of macroinvertebrates in two Alpine streams after a supraseasonal drought. As water returned, a total of 10 sampling sessions were carried out, and temporal patterns in diversity, density, and taxonomic composition of benthic communities, as well as in the percentage of functional feeding groups, were investigated. We found that the resistance of invertebrate communities in Alpine streams is generally low: drought markedly reduced the diversity and density of macroinvertebrates. Conversely, our results suggest that the passive dispersal by drift from the upstream river sections seems the most probable mechanism promoting the post‐drought recovery. Nevertheless, this resilience ability appears to be stream specific and influenced by intrinsic stream characteristics, including the flow permanence and distance from the nearest upstream perennial reach. This work sheds light on the ecological consequences of droughts on macroinvertebrate communities. As flow intermittency in Alpine areas is expected to intensify under current global change scenarios, results of this study provide important information to predict changes in the taxonomic composition and diversity of macroinvertebrate communities.     

阳宗海浮游生物群落结构研究

采用生物多样性指数方法,对2013年阳宗海湖泊的浮游生物群落结构进行研究。结果表明,阳宗海湖泊共检出浮游植物7门39属,蓝藻门的拟鱼腥藻和泽丝藻为优势种群;浮游动物鉴定出33种,轮虫为优势种;浮游植物和浮游动物的香浓多样性指数在1.10~2.83之间,均匀度指数在0.37~0.88之间,属于中度污染,阳宗海湖泊已处于中营养状态,并有向富营养化过渡的趋势。     

LINKING RIVER MANAGEMENT TO SPECIES CONSERVATION USING DYNAMIC LANDSCAPE‐SCALE MODELS

Efforts to conserve stream and river biota could benefit from tools that allow managers to evaluate landscape‐scale changes in species distributions in response to water management decisions. We present a framework and methods for integrating hydrology, geographic context and metapopulation processes to simulate effects of changes in streamflow on fish occupancy dynamics across a landscape of interconnected stream segments. We illustrate this approach using a 482 km² catchment in the southeastern US supporting 50 or more stream fish species. A spatially distributed, deterministic and physically based hydrologic model is used to simulate daily streamflow for sub‐basins composing the catchment. We use geographic data to characterize stream segments with respect to channel size, confinement, position and connectedness within the stream network. Simulated streamflow dynamics are then applied to model fish metapopulation dynamics in stream segments, using hypothesized effects of streamflow magnitude and variability on population processes, conditioned by channel characteristics. The resulting time series simulate spatially explicit, annual changes in species occurrences or assemblage metrics (e.g. species richness) across the catchment as outcomes of management scenarios. Sensitivity analyses using alternative, plausible links between streamflow components and metapopulation processes, or allowing for alternative modes of fish dispersal, demonstrate large effects of ecological uncertainty on model outcomes and highlight needed research and monitoring. Nonetheless, with uncertainties explicitly acknowledged, dynamic, landscape‐scale simulations may prove useful for quantitatively comparing river management alternatives with respect to species conservation. Published 2012. This article is a U.S. Government work and is in the public domain in the USA.     

GigaMatrix: an ultra high-throughput tool for accessing biodiversity

Recombinant approaches for tapping into the biodiversity present in nature for the discovery of novel enzymes and biosynthetic pathways can result in large gene libraries. Likewise, laboratory evolution techniques can result in large but potentially valuable libraries. Thorough screening of these libraries requires ultra high-throughput methods. The GigaMatrix^™ screening platform addresses this opportunity using reusable high-density plates with 100,000 to 1,000,000 through-hole wells in a microplate footprint. In addition to throughputs of over 10⁷ wells per day, the platform offers a significant reduction in reagent use and waste, has fully integrated automated “cherry picking,” and uses no complicated dispensing equipment. Wells containing putative hits from targeted fluorescent liquid phase assays are revealed by a fluorescent imaging system. Vision-guided robotics are utilized to recover hits by accessing individual 200 μm and smaller wells with a disposable sterile needle. The GigaMatrix platform has proven to be an effective and efficient tool for screening gene libraries for both discovery and evolution applications.     

Chemical warfare and survival strategies in bacterial range expansions

Dispersal of species is a fundamental ecological process in the evolution and maintenance of biodiversity. Limited control over ecological parameters has hindered progress in understanding of what enables species to colonize new areas, as well as the importance of interspecies interactions. Such control is necessary to construct reliable mathematical models of ecosystems. In our work, we studied dispersal in the context of bacterial range expansions and identified the major determinants of species coexistence for a bacterial model system of three Escherichia coli strains (toxin-producing, sensitive and resistant). Genetic engineering allowed us to tune strain growth rates and to design different ecological scenarios (cyclic and hierarchical). We found that coexistence of all strains depended on three strongly interdependent factors: composition of inoculum, relative strain growth rates and effective toxin range. Robust agreement between our experiments and a thoroughly calibrated computational model enabled us to extrapolate these intricate interdependencies in terms of phenomenological biodiversity laws. Our mathematical analysis also suggested that cyclic dominance between strains is not a prerequisite for coexistence in competitive range expansions. Instead, robust three-strain coexistence required a balance between growth rates and either a reduced initial ratio of the toxin-producing strain, or a sufficiently short toxin range.     

Land use/cover dynamics and their effects in the Gerado catchment,northeastern Ethiopia

This paper analyses the land use/cover dynamics of land degradation through the interpretation of aerial photographs (1958 and 1980) and 2006 SPOT-5 satellite image of the Gerado catchment. Other, non-visual data were gathered from personal interview and focus group discussions conducted in 2010 and 2011 with local elders, farmers and development (agricultural extension) agents. The results identified the presence of cultivated and rural settlement land, shrubland, woodland, bare land, grassland, urban built up area and forest. Throughout the period 1958–2006, urban built-up area, forest and cultivated and rural settlement land expanded at an average rate of 6.85%, 1.85% and 0.14% per year at the expense of shrub, wood and grasslands, which declined by 0.77%, 0.21%, 0.65% per year, respectively. The land use/cover dynamics of 1958–2006 resulted in the reduction/loss of biodiversity, occurrence of high soil erosion and ramification of gullies. The triggers for these changes were population growth, land cultivation, expansion of farmland, inappropriate land management, civil war and fuel wood demand. These led to further land degradation and more food insecurity among many farming households. Land resources have to be used according to their suitability. Thus, the exposed and steep mountains of the area have to be protected from cultivation and should be re-afforested. The paper discusses other implications for management and policy formulation also.     

近 20 年国外系统保护规划研究进展及启示

运用系统保护规划（SCP）的方法建立保护地（protected area）对生物多样性资源及其所提供的生态系统服务价值具有重要保护作用。笔者归纳总结了自 19 世纪 80 年代以来系统保护规划思想产生和发展的历程,随后基于近 20 年来系统保护规划相关文献,梳理得到现阶段影响保护规划最为核心的两大背景—气候变化及生态系统服务,此背景对系统保护规划六步法关键步骤的研究动态产生深刻影响,并推动了新的研究进展的产生,其中涵盖了规划理念更新、保护目标多元化、数据及模型算法拓展、管理框架变更。笔者结合中国的自然保护地规划背景和相关实践,从关键内容、监测评估、实施管理 3 个方面提出未来的研究方向,以期通过借鉴国际上保护规划的方法、工具、经验对完善中国的保护地体系构建的实践提供参考。     

增进城市地区生物多样性——以新加坡模式为例

自 1963 年以来,新加坡开展实施了绿化计划,并经历了从“花园城市”到“花园中的亲生态城市”的演变。为了在新加坡实现生物多样性保护,国家公园局制定了自然保护蓝图,重点介绍该规划实施的关键是利用技术创新。新加坡城市生物多样性指数是一种评价生物多样性成效的自我评估工具,已在全球范围内的多个城市得到应用。     

传统酸面团中细菌与酵母菌的分离与鉴定

为进一步描述我国传统面食发酵剂的理化性质和菌落组成,收集了北方地区6份发酵剂样品,测定了其酸度和菌落总数,并对分离、纯化、初筛后得到的75株细菌和60株酵母菌进行了测序鉴定。结果显示,样品pH值范围为3.73~5.46,总滴定酸度为8.3~19.8 mL;乳酸菌和酵母菌的计数结果分别为8.35±0.07~9.75±0.12 Log cfu/g,6.31±0.22~8.68±0.04 Log cfu/g。鉴定出包括短乳杆菌(Lactobacillus brevis)、植物乳杆菌(Lactobacillus plantarum)和旧金山乳杆菌(Lactobacillus sanfranciscensis)在内的乳酸菌8种;酵母菌4种,其中优势菌为酿酒酵母(Saccharomyces cerevisiae);其他细菌6种,主要为解淀粉芽孢杆菌(B.amyloliquefaciens)、地衣芽孢杆菌(B.licheniformis)和醋杆菌。结果表明,我国传统面食发酵剂菌相复杂,以酵母菌和乳酸菌为主,还包括芽孢杆菌、醋酸杆菌在内的多种其他细菌,甚至可能含有致病菌。通过比较细菌和酵母在不同酸面团样品中的分布,发现不同来源样品的微生物种类组成存在差异。