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1.
黎艺明  李才 《环境化学》2013,32(1):166-167
在我国填埋仍是垃圾处理的主要方式.垃圾产生的渗滤液量大、组分复杂,重金属及有机物含量极高,对土壤及地下水环境污染严重[1].渗滤液污染地下环境的过程主要包括污染物质在包气带中的垂向运移和透过包气带后在含水层中的侧向运移.因此,包气带是阻止渗滤液污染含水层的天然屏障,可以通过对污染物质的阻截和自然衰减,起到削弱污染、保护含水层的作用.因此研究垃圾渗滤液污染物,特别是在不同岩性包气带介质中的迁移转化十分必要.  相似文献   

2.
水溶性污染物和有机污染物在非饱和带的运动规律是当前土壤物理学研究的前沿领域.模拟反应性溶质的运移模型,必须包含溶质和土壤基质之间的保持和释放反应.本文简要综述土壤对溶质保持反应的平衡模型、动力学模型和多反应模型的主要特点.  相似文献   

3.
土壤胶体对重金属运移行为的影响   总被引:10,自引:0,他引:10  
刘冠男  刘新会 《环境化学》2013,(7):1308-1317
累积在表层土壤中的重金属,在一定条件下可以向地下迁移,进而影响地下水水质.由于现有污染物运移预测模型对重金属等污染物在土壤中运移的预测与实际监测结果偏差巨大,土壤胶体对土壤重金属运移的影响越来越受到人们的重视.土壤胶体组成丰富,在土壤环境中广泛存在.土壤胶体能够与重金属等污染物质相结合,对重金属等污染物质的运移产生重要影响.土壤胶体运移和土壤胶体与重金属的相互作用受到水动力、pH、离子强度、胶体粒径、土壤含水率等多种物理化学条件的影响.本文综述了土壤胶体对土壤重金属运移影响的诸多因素,介绍了胶体作用下重金属等污染物在多孔介质中的运移模型,提出了当前研究中存在的问题,并对今后需要展开的工作提出了建议.  相似文献   

4.
长江下游重点江段水质污染及对鱼类的毒性影响   总被引:6,自引:0,他引:6  
通过对长江下游安庆、南京、镇江、南通4江段水质污染及其对鱼类毒性影响的调查监测可发现,长江下游江段主航道水质较好,符合国家地面水Ⅱ类水质标准.但近岸带水质由于受污染带的影响,水质污染较严重,其主要污染物为石油类和挥发酚等.上述这些污染物质对鱼类具有一定的毒性影响,其不但可引起鱼类的急性中毒,而且可诱发鱼类产生微核,并对鼠伤寒沙门氏菌TA98菌株表现出一定的致突变性.同时在上述几个江段鱼体内可检出较高的蓄积性污染物的残留量.研究结果显示,长江下游江段正在遭受沿江诸多工业废水的污染,尤其是污染带的作用,并且这种污染对区域性渔业有一定的影响  相似文献   

5.
焦化厂多环芳烃污染场地的环境评价实证研究   总被引:1,自引:0,他引:1  
通过实地调查某焦化厂污染场地污染现状,结果表明:该场地土壤和地下水以多环芳烃(PAHs)有机类污染为主,土壤中苯并(仅)芘和多环芳烃污染以1.5m以内表层土污染为主,随着深度的增加浓度逐渐降低,弱透水层表现出良好的阻隔作用。沿着地下水流动方向,地下水中多环芳烃浓度逐渐降低,经过约400m的迁移,由17296μg/L降至111μg/L;苯并(α)芘经过200m的迁移,由18.3μg/L降至0,地下水流动导致污染物在包气带横向扩散。1号孔、3号孔和4号孔所在地表层土壤中苯并(α)芘的单个污染物的致癌风险分别为0.0278、0.0209和1.496,远远超出可接受水平,因此上述孔位所在地附近表层土壤需重点治理。  相似文献   

6.
本文采用有机污染现状评价法和环境影响度评价法对新疆库尔勒市平原区22组地下水水样进行评价,并对其影响因素进行了分析.地下水有机污染物检测结果显示,无有机污染物超标项,有6项有机污染物检出,分别为反-1,2-二氯乙烯、顺-1,2-二氯乙烯、三氯甲烷、1,2-二氯乙烷、四氯乙烯和甲苯,检出率最高的指标是甲苯(检出率为27.3%),其余5项检出率均为4.5%.地下水有机污染现状评价结果表明,研究区内甲苯未污染占72.7%、轻度污染占27.3%,其余5项未污染占95.5%、轻度污染占4.5%.地下水环境影响度评价结果表明,研究区地下水体中的有机污染物对人和环境没有明显的潜在危害.库尔勒市平原区地下水中有机污染物检出主要受工业污染源、生活污染源、农业污染源、土地利用类型和包气带岩性的影响.  相似文献   

7.
再生水回灌地下水环境安全风险评价技术方法研究   总被引:2,自引:0,他引:2  
再生水回灌是水资源管理的一条有效途径,也是污水再生利用的重要发展方向。然而,当再生水以农灌、土壤含水层处理(SAT)、河湖入渗和井灌等方式进行地下水回灌时,不可避免的会在回补地下水的过程中造成对地下水环境的污染风险。针对不同回灌方式建立适用于我国的再生水回灌地下水环境安全风险评价技术体系至关重要。借鉴国内外地下水污染风险评价方法,综合分析再生水回灌对地下水产生风险的关键环节,采用层析分析法,从回灌水特征污染物特性、回灌区地下水固有脆弱性以及回灌工程布设方式3个方面,针对地表灌溉、河湖入渗和井灌3种回灌方式,建立了包含污染物浓度水平、分配系数、溶解度、半衰期、半致死剂量、地下水埋深、降雨入渗补给量、地形坡度、土壤介质、包气带介质、含水层介质、含水层厚度、回灌强度、回灌周期、回灌水停留时间以及取水点与回灌点水平距离16个指标在内的风险评价指标体系。在此基础上,结合地下水使用功能,以20个典型再生水回灌场地调研结果和160种再生水回灌地下水污染风险因子物化特性为数据基础,对各指标进行了风险水平的划分,基于聚类分析法,采用各指标风险指数相乘的风险表征方法计算总风险指数,构建了再生水回灌地下水环境安全风险评价技术方法。该方法有效的避免了指标权重计算的主观性,并且能够直观的找出导致风险的主要因素。结果表明:利用建立的风险评价技术方法可将我国再生水回灌地下水环境安全风险划分为3级,风险值〈5为一级,风险值在5-15之间为二级,风险值〉15为三级。在某再生水回灌场地的应用表明,该回灌区地下水环境安全风险为二级,同时得出回灌水特征污染物特性指标是造成该回灌区地下水环境风险的主要因素。  相似文献   

8.
石油污染土壤及地下水的生物修复进展[综述]   总被引:2,自引:2,他引:0  
所谓石油污染土壤的生物修复[2](Bioremediation),是指利用微生物及其他生物,将存在于土壤、地下水和海洋中的有毒有害的石油污染物现场降解成二氧化碳和水或转化成为无害物质的工程技术系统.它是传统的生物处理方法的延伸,其创新之处在于它治理的对象是较大面积的污染.由于现场环境的复杂性,因而产生了许多不同于治理点污染的概念和技术措施.与物理、化学土壤修复技术相比,生物修复技术具有多种优点[1,2].KurodaDannaR[3]曾以美国应用实例对生物修复技的特点进行过详细的归纳与总结:既可…  相似文献   

9.
针对苏南某农业区浅层地下水中DDTs的污染特征进行了初步分析,结果表明,浅层地下水中DDTs最大检出质量浓度为1.04 μg·L-1,最大检出率为36.67%.浅层地下水DDTs污染呈散状分布,浓度高值点集中在研究区东北部,污染范围大,且表现出丰水期、平水期和枯水期含量依次递减的季节性变化特征.该地区包气带防污性能良好,黏土矿物和有机碳对DDTs吸附作用较强,可阻滞其向浅层地下水环境中迁移,是造成部分地段浅层地下水未检出DDTs污染的重要原因.受污染地表水体的垂向入渗是导致浅层地下水DDTs污染的直接原因,其侧向补给可能是浅层地下水DDTs污染的重要来源之一,且污染范围往往局限于地表水体附近地带.  相似文献   

10.
随着人类开采石油量的增加、海上交通运输的发展、海底溢油事故的发生以及工业民用废水排放的日益增长,海洋环境承受着来自外界的巨大危害。并且,海洋中的石油类污染物由水体迁移至土壤,给周边土壤也带来极大影响。石油类物质已成为崇明西沙湿地土壤主要的污染物之一。基于此,于2014年3月至12月在崇明西沙湿地设置5个采样点,利用紫外分光光度计、GC-MS等仪器对石油类污染物的浓度和组分进行测定,研究了土壤石油类污染物含量随季节变化的情况及其对植被类型的影响,并对污染物组分和来源进行解析。结果表明,湿地土壤石油类污染物主要以碳原子数小于8的饱和直链烷烃和饱和支链烷烃为主,同时还含有少量的烯烃、含氧杂环、含氮杂环等物质。该地区石油类污染物平均含量为47.3 mg·kg~(-1),其中春季最高,秋季最低;单因子污染指数为0.079~0.155,土壤尚处于清洁水平。湿地土壤石油类含量呈现季节性变化,与外源输入、海上作业及微生物的分解作用有关。3种植被群落土壤和光滩石油类污染物含量各异,且随季节变化明显,其中光滩群落土壤石油类污染物含量最低,芦苇群落土壤石油类污染物含量最高,且4个季节均明显高于其它群落,分析其原因可能是芦苇特殊的根系结构对石油有较好的截留和吸附作用。  相似文献   

11.
When deciding how to conserve biodiversity, practitioners navigate diverse missions, sometimes conflicting approaches, and uncertain trade-offs. These choices are based not only on evidence, funders’ priorities, stakeholders’ interests, and policies, but also on practitioners’ personal experiences, backgrounds, and values. Calls for greater reflexivity—an individual or group's ability to examine themselves in relation to their actions and interactions with others—have appeared in the conservation science literature. But what role does reflexivity play in conservation practice? We explored how self-reflection can shape how individuals and groups conserve nature. To provide examples of reflexivity in conservation practice, we conducted a year-long series of workshop discussions and online exchanges. During these, we examined cases from the peer-reviewed and gray literature, our own experiences, and conversations with 10 experts. Reflexivity among practitioners spanned individual and collective levels and informal and formal settings. Reflexivity also encompassed diverse themes, including practitioners’ values, emotional struggles, social identities, training, cultural backgrounds, and experiences of success and failure. Reflexive processes also have limitations, dangers, and costs. Informal and institutionalized reflexivity requires allocation of limited time and resources, can be hard to put into practice, and alone cannot solve conservation challenges. Yet, when intentionally undertaken, reflexive processes might be integrated into adaptive management cycles at multiple points, helping conservation practitioners better reach their goals. Reflexivity could also play a more transformative role in conservation by motivating practitioners to reevaluate their goals and methods entirely. Reflexivity might help the conservation movement imagine and thus work toward a better world for wildlife, people, and the conservation sector itself.  相似文献   

12.
Protected areas (PAs) are often implemented without consideration of already existing PAs, which is likely to cause an overrepresentation of certain biophysical conditions. We assessed the representativeness of the current PA network with regard to the world's biophysical conditions to highlight which conditions are underprotected and where these conditions are located. We overlaid terrestrial and marine PAs with information on biophysical conditions (e.g., temperature, precipitation, and elevation) and then quantified the percentage of area covered by the PA network. For 1 variable at a time in the terrestrial realm, high temperature, low precipitation, and medium and very high elevation were underrepresented. For the marine realm, low and medium sea surface temperature (SST), medium and high sea surface salinity (SSS), and the deep sea were underrepresented. Overall, protection was evenly distributed for elevation across the terrestrial realm and SST across the marine realm. For 2 variables at a time, cold and very dry terrestrial environments had mostly low protection, which was also the case for low SST and low and medium SSS across most depths for marine environments. Low protection occurred mostly in the Sahara and the Arabian Peninsula for the terrestrial realm and along the Tropic of Capricorn and toward the poles for the marine realm. Although biodiversity measures are of prime importance for the design of PA networks, highlighting biophysical gaps in current PAs adds a frequently overlooked perspective. These gaps may weaken the potential of PAs to conserve biodiversity. Thus, our results may provide useful insights for researchers, practitioners, and policy makers to establish a more comprehensive global PA network.  相似文献   

13.
Biodiversity indicators are used to inform decisions and measure progress toward global targets, such as the United Nations Sustainable Development Goals. Indicators aggregate and simplify complex information, so underlying information influencing its reliability and interpretation (e.g., variability in data and uncertainty in indicator values) can be lost. Communicating uncertainty is necessary to ensure robust decisions and limit misinterpretations of trends, yet variability and uncertainty are rarely quantified in biodiversity indicators. We developed a guide to representing uncertainty and variability in biodiversity indicators. We considered the key purposes of biodiversity indicators and commonly used methods for representing uncertainty (standard error, bootstrap resampling, and jackknife resampling) and variability (quantiles, standard deviation, median absolute deviation, and mean absolute deviation) with intervals. Using 3 high-profile biodiversity indicators (Red List Index, Living Planet Index, and Ocean Health Index), we tested the use, suitability, and interpretation of each interval method based on the formulation and data types underpinning the indicators. The methods revealed vastly different information; indicator formula and data distribution affected the suitability of each interval method. Because the data underpinning each indicator were not normally distributed, methods relying on normality or symmetrical spread were unsuitable. Quantiles, bootstrapping, and jackknifing provided useful information about the underlying variability and uncertainty. We built a decision tree to inform selection of the appropriate interval method to represent uncertainty or variation in biodiversity indicators, depending on data type and objectives. Our guide supports transparent and effective communication of biodiversity indicator trends to facilitate accurate interpretation by decision makers.  相似文献   

14.
Global insect pollinator declines have prompted habitat restoration efforts, including pollinator-friendly gardening. Gardens can provide nectar and pollen for adult insects and offer reproductive resources, such as nesting sites and caterpillar host plants. We conducted a review and meta-analysis to examine how decisions made by gardeners on plant selection and garden maintenance influence pollinator survival, abundance, and diversity. We also considered characteristics of surrounding landscapes and the impacts of pollinator natural enemies. Our results indicated that pollinators responded positively to high plant species diversity, woody vegetation, garden size, and sun exposure and negatively to the separation of garden habitats from natural sites. Within-garden features more strongly influenced pollinators than surrounding landscape factors. Growing interest in gardening for pollinators highlights the need to better understand how gardens contribute to pollinator conservation and how some garden characteristics can enhance the attractiveness and usefulness of gardens to pollinators. Further studies examining pollinator reproduction, resource acquisition, and natural enemies in gardens and comparing gardens with other restoration efforts and to natural habitats are needed to increase the value of human-made habitats for pollinators.  相似文献   

15.
Efforts to tackle the current biodiversity crisis need to be as efficient and effective as possible given chronic underfunding. To inform decision-makers of the most effective conservation actions, it is important to identify biases and gaps in the conservation literature to prioritize future evidence generation. We used the Conservation Evidence database to assess the state of the global literature that tests conservation actions for amphibians and birds. For the studies in the database, we investigated their spatial and taxonomic extent and distribution across biomes, effectiveness metrics, and study designs. Studies were heavily concentrated in Western Europe and North America for birds and particularly for amphibians, and temperate forest and grassland biomes were highly represented relative to their percentage of land coverage. Studies that used the most reliable study designs—before-after control-impact and randomized controlled trials—were the most geographically restricted and scarce in the evidence base. There were negative spatial relationships between the numbers of studies and the numbers of threatened and data-deficient species worldwide. Taxonomic biases and gaps were apparent for amphibians and birds—some entire orders were absent from the evidence base—whereas others were poorly represented relative to the proportion of threatened species they contained. Metrics used to evaluate effectiveness of conservation actions were often inconsistent between studies, potentially making them less directly comparable and evidence synthesis more difficult. Testing conservation actions on threatened species outside Western Europe, North America, and Australasia should be prioritized. Standardizing metrics and improving the rigor of study designs used to test conservation actions would also improve the quality of the evidence base for synthesis and decision-making.  相似文献   

16.
China's Belt and Road Initiative (BRI) sets to create connections and build infrastructure across Eurasia, Asia, and parts of the African continent in its initial phase and is the largest infrastructure project of all time. Any infrastructure project on this scale will necessarily pass through ecofragile regions and key biodiversity areas (KBAs). This creates an imperative to identify possible areas of impact and probable effects on conservation values to facilitate adaptive planning and to mitigate, minimize, or avoid impacts. Using the highest resolution route maps of the BRI available, I overlaid the proposed road and rail routes on KBAs, protected areas, and predicted biodiversity hotspots for over 4138 animal and 7371 plant species. I also assessed the relationship between the proposed route with the distribution of mines across BRI countries and the proportion of deforestation and forest near routes. Infrastructure, especially mining, was clustered near the proposed route; thus, construction and development along the route may increase the size and number of mines. Up to 15% of KBAs were within 1 km of proposed railways. Thus, planned and probable development along the routes may pose a significant risk to biodiversity, especially because the majority of KBAs are unprotected. Many biodiversity hotspots for different taxa were near the route. These hotspots varied between taxa, making systematic management and environmental impact assessments an effective strategy for at least some taxa. A combination of planning and mitigation strategies will likely be necessary to protect the most important areas for biodiversity proximal to development, especially in currently unprotected KBAs and other regions that need protection. A fuller assessment of trade-offs between conservation and other values will be necessary to make good decisions for each project and site being developed, including potentially modifying parts of the route to minimize impacts. Modification or foregoing of infrastructure may be needed if stakeholders consider the conservation costs too high.  相似文献   

17.
Despite broad recognition of the value of social sciences and increasingly vocal calls for better engagement with the human element of conservation, the conservation social sciences remain misunderstood and underutilized in practice. The conservation social sciences can provide unique and important contributions to society's understanding of the relationships between humans and nature and to improving conservation practice and outcomes. There are 4 barriers—ideological, institutional, knowledge, and capacity—to meaningful integration of the social sciences into conservation. We provide practical guidance on overcoming these barriers to mainstream the social sciences in conservation science, practice, and policy. Broadly, we recommend fostering knowledge on the scope and contributions of the social sciences to conservation, including social scientists from the inception of interdisciplinary research projects, incorporating social science research and insights during all stages of conservation planning and implementation, building social science capacity at all scales in conservation organizations and agencies, and promoting engagement with the social sciences in and through global conservation policy‐influencing organizations. Conservation social scientists, too, need to be willing to engage with natural science knowledge and to communicate insights and recommendations clearly. We urge the conservation community to move beyond superficial engagement with the conservation social sciences. A more inclusive and integrative conservation science—one that includes the natural and social sciences—will enable more ecologically effective and socially just conservation. Better collaboration among social scientists, natural scientists, practitioners, and policy makers will facilitate a renewed and more robust conservation. Mainstreaming the conservation social sciences will facilitate the uptake of the full range of insights and contributions from these fields into conservation policy and practice.  相似文献   

18.
Circuit-theory applications to connectivity science and conservation   总被引:1,自引:0,他引:1  
Conservation practitioners have long recognized ecological connectivity as a global priority for preserving biodiversity and ecosystem function. In the early years of conservation science, ecologists extended principles of island biogeography to assess connectivity based on source patch proximity and other metrics derived from binary maps of habitat. From 2006 to 2008, the late Brad McRae introduced circuit theory as an alternative approach to model gene flow and the dispersal or movement routes of organisms. He posited concepts and metrics from electrical circuit theory as a robust way to quantify movement across multiple possible paths in a landscape, not just a single least-cost path or corridor. Circuit theory offers many theoretical, conceptual, and practical linkages to conservation science. We reviewed 459 recent studies citing circuit theory or the open-source software Circuitscape. We focused on applications of circuit theory to the science and practice of connectivity conservation, including topics in landscape and population genetics, movement and dispersal paths of organisms, anthropogenic barriers to connectivity, fire behavior, water flow, and ecosystem services. Circuit theory is likely to have an effect on conservation science and practitioners through improved insights into landscape dynamics, animal movement, and habitat-use studies and through the development of new software tools for data analysis and visualization. The influence of circuit theory on conservation comes from the theoretical basis and elegance of the approach and the powerful collaborations and active user community that have emerged. Circuit theory provides a springboard for ecological understanding and will remain an important conservation tool for researchers and practitioners around the globe.  相似文献   

19.
Scholars across all disciplines have long been interested in how knowledge moves within and beyond their community of peers. Rapid environmental changes and calls for sustainable management practices mean the best knowledge possible is needed to inform decisions, policies, and practices to protect biodiversity and sustainably manage vulnerable natural resources. Although the conservation literature on knowledge exchange (KE) and knowledge mobilization (KM) has grown in recent years, much of it is based on context‐specific case studies. This presents a challenge for learning cumulative lessons from KE and KM research and thus effectively using knowledge in conservation and natural resources management. Although continued research on the gap between knowledge and action is valuable, overarching conceptual frameworks are now needed to enable summaries and comparisons across diverse KE‐KM research. We propose a knowledge‐action framework that provides a conceptual roadmap for future research and practice in KE/KM with the aim of synthesizing lessons learned from contextual case studies and guiding the development and testing of hypotheses in this domain. Our knowledge‐action framework has 3 elements that occur at multiple levels and scales: knowledge production (e.g., academia and government), knowledge mediation (e.g., knowledge networks, actors, relational dimension, and contextual dimension), and knowledge‐based action (e.g., instrumental, symbolic, and conceptual). The framework integrates concepts from the sociology of science in particular, and serves as a guide to further comprehensive understanding of knowledge exchange and mobilization in conservation and sustainable natural resource management.  相似文献   

20.
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.  相似文献   

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