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121.
粤北南岭大宝山矿流域山水林田湖草修复阻力与优先级分析 总被引:1,自引:0,他引:1
遵循“防源、控流、治汇”理念,以粤北南岭大宝山矿区作为风险源,以所在流域为研究区,分析研究区主要阻力因素,采用最小累积阻力模型建立区域生态阻力面;利用Jenks自然断点法,分析生态修复优先级,提出分区治理重点和对策。研究结果表明:研究区综合阻力系数处于9-32之间,各评价指标的阻力面空间分布格局相似,其阻力值呈现出东南部大,西北部小的空间格局;长期的矿业开采污染了流域生态环境,且距离矿区越近的区域生态修复的优先性越高。将研究区分为4个优先级区,各区修复优先性依次为Ⅰ区 > Ⅱ区 > Ⅲ区 > Ⅳ区。Ⅰ区重点在于治水,提高pH、降低重金属有效态含量和增加地表植被覆盖度。Ⅱ区重点在于河流治理与治土,确保污染减排,增强拦泥库的废水调节。Ⅲ区、Ⅳ区核心在治土,逐步改善土壤条件。研究结果为修复项目在时空尺度上落地和科学治理提供科学依据。 相似文献
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Stphanie Sherpa Maya Guguen Julien Renaud Michael G. B. Blum Thierry Gaude Frdric Laporte Mustafa Akiner Bulent Alten Carles Aranda Hlne Barre‐Cardi Romeo Bellini Mikel Bengoa Paulis Xiao‐Guang Chen Roger Eritja Eleonora Flacio Cipriano Foxi Intan H. Ishak Katja Kalan Shinji Kasai Fabrizio Montarsi Igor Pajovi Duan Petri Rosa Termine Nataa Turi Gonzalo M. Vazquez‐Prokopec Enkelejda Velo Goran Vignjevi Xiaohong Zhou Laurence Desprs 《Ecology and evolution》2019,9(22):12658-12675
Invasive species can encounter environments different from their source populations, which may trigger rapid adaptive changes after introduction (niche shift hypothesis). To test this hypothesis, we investigated whether postintroduction evolution is correlated with contrasting environmental conditions between the European invasive and source ranges in the Asian tiger mosquito Aedes albopictus. The comparison of environmental niches occupied in European and source population ranges revealed more than 96% overlap between invasive and source niches, supporting niche conservatism. However, we found evidence for postintroduction genetic evolution by reanalyzing a published ddRADseq genomic dataset from 90 European invasive populations using genotype–environment association (GEA) methods and generalized dissimilarity modeling (GDM). Three loci, among which a putative heat‐shock protein, exhibited significant allelic turnover along the gradient of winter precipitation that could be associated with ongoing range expansion. Wing morphometric traits weakly correlated with environmental gradients within Europe, but wing size differed between invasive and source populations located in different climatic areas. Niche similarities between source and invasive ranges might have facilitated the establishment of populations. Nonetheless, we found evidence for environmental‐induced adaptive changes after introduction. The ability to rapidly evolve observed in invasive populations (genetic shift) together with a large proportion of unfilled potential suitable areas (80%) pave the way to further spread of Ae. albopictus in Europe. 相似文献
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William K. Cornwell William D. Pearse Rhiannon L. Dalrymple Amy E. Zanne 《Ecography》2019,42(11):1819-1831
The era of big biodiversity data has led to rapid, exciting advances in the theoretical and applied biological, ecological and conservation sciences. While large genetic, geographic and trait databases are available, these are neither complete nor random samples of the globe. Gaps and biases in these databases reduce our inferential and predictive power, and this incompleteness is even more worrisome because we are ignorant of both its kind and magnitude. We performed a comprehensive examination of the taxonomic and spatial sampling in the most complete current databases for plant genes, locations and functional traits. To do this, we downloaded data from The Plant List (taxonomy), the Global Biodiversity Information Facility (locations), TRY (traits) and GenBank (genes). Only 17.7% of the world's described and accepted land plant species feature in all three databases, meaning that more than 82% of known plant biodiversity lacks representation in at least one database. Species coverage is highest for location data and lowest for genetic data. Bryophytes and orchids stand out taxonomically and the equatorial region stands out spatially as poorly represented in all databases. We have highlighted a number of clades and regions about which we know little functionally, spatially and genetically, on which we should set research targets. The scientific community should recognize and reward the significant value, both for biodiversity science and conservation, of filling in these gaps in our knowledge of the plant tree of life. 相似文献
126.
As part of the long‐term fusion of evolutionary biology and ecology (Ford, 1964), the field of community genetics has made tremendous progress in describing the impacts of plant genetic variation on community and ecosystem processes. In the “genes‐to‐ecosystems” framework (Whitham et al., 2003), genetically based traits of plant species have ecological consequences, but previous studies have not identified specific plant genes responsible for community phenotypes. The study by Barker et al. (2019) in this issue of Molecular Ecology uses an impressive common garden experiment of trembling aspen (Figure 1) to test for the genetic basis of tree traits that shape the insect community composition. Using a Genome‐Wide Association Study (GWAS), they found that genomic regions associated with phytochemical traits best explain variation in herbivore community composition, and identified specific genes associated with different types of leaf‐modifying herbivores and ants. This is one of the first studies to identify candidate genes underlying the heritable plant traits that explain patterns of insect biodiversity. 相似文献
127.
Eva Maire Joshua Cinner Laure Velez Cindy Huchery Camilo Mora Stephanie Dagata Laurent Vigliola Laurent Wantiez Michel Kulbicki David Mouillot 《Ecology letters》2016,19(4):351-360
The depletion of natural resources has become a major issue in many parts of the world, with the most accessible resources being most at risk. In the terrestrial realm, resource depletion has classically been related to accessibility through road networks. In contrast, in the marine realm, the impact on living resources is often framed into the Malthusian theory of human density around ecosystems. Here, we develop a new framework to estimate the accessibility of global coral reefs using potential travel time from the nearest human settlement or market. We show that 58% of coral reefs are located < 30 min from the nearest human settlement. We use a case study from New Caledonia to demonstrate that travel time from the market is a strong predictor of fish biomass on coral reefs. We also highlight a relative deficit of protection on coral reef areas near people, with disproportional protection on reefs far from people. This suggests that conservation efforts are targeting low‐conflict reefs or places that may already be receiving de facto protection due to their isolation. Our global assessment of accessibility in the marine realm is a critical step to better understand the interplay between humans and resources. 相似文献
129.
The global market for herbal medicine is growing steadily. The usage of herbal medicine is particularly common in many parts of Africa; the World Health Organization estimates that approximately 80% of Africans rely on traditional African medicines (TAMs) for treating various diseases. TAMs hold promise in preventive treatment, early disease intervention and personalized medicine. However, clinical integration of TAMs is restricted due to limited information concerning their characterization. Presently, many studies on TAMs utilize a reductionist approach, making it extremely difficult to understand the holistic modifying effects that these therapeutic agents may have on biological systems. Fortunately, emerging technologies such as metabolomics platforms adopt a top-down strategy that permits a holistic evaluation of the components, metabolic pathways and biomarkers modified by TAMs, which can aid in addressing common concerns over safety and toxicity, while also ensuring that quality control standards are met. Metabolomics approaches may also be beneficial for advancing our understanding of the efficacy and mechanism of action of TAMs, and may contribute to the advancement of research and drug discovery, early diagnosis, preventive treatment and TAMs-driven personalized medicine in Africa. This review also considers the main challenges that may hinder the adoption and integration of metabolomics approaches in research on TAMs in Africa and suggests possible solutions. 相似文献
130.