垃圾渗滤液中污染物在包气带运移模拟实验及预测

为揭示垃圾渗滤液中污染物在包气带中的迁移转化规律,通过静态吸附、静态降解、动态土柱和数学模型预测等方法进行模拟实验。结果表明,包气带对污染物的吸附过程是线性的,即S=KdC,吸附系数Kd=0.0976;降解曲线符合一级动力学方程,即C=C0e-λt,降解系数λ=0.0324d-1;弥散过程符合对流-弥散迁移转化模型,弥散系数D=0.00435m2·d-1,由此确定了污染物迁移数学模型。通过动态土柱实验验证了模型的可靠性,并利用模型对垃圾渗滤液中有机污染物(COD)的时空分布进行预测。     

天然有机质疏水性定量方法及吸附预测模型

天然有机质是有机污染物在土壤和水环境中的重要赋存相，显著影响有机污染物的传输、归趋和生物有效性.有机污染物的有机碳-水分配系数是污染物迁移积累模型的核心参数.如何准确、快速地评估有机污染物在天然有机质上的吸附行为是环境科学研究的一个重要科学问题.该方向的研究内容主要包括有机污染物和天然有机质性质定量描述、有机污染物-天然有机质作用机制解析和吸附预测模型构建三个环节.学界在有机污染物-天然有机质作用机制解析方向取得了丰硕的成果，在天然有机质性质定量描述和吸附预测模型构建方向仍有广阔的发展空间.本文系统评估了现有的天然有机质疏水性定量方法和天然有机质吸附预测模型.通过对方法和模型优缺点和适用范围的系统分析，揭示了现有研究的不足，展望了未来研究的主要方向.     

水位波动对土壤苯系物的污染运移和水化学影响

迄今为止,水环境的BTEX(苯系物)污染仍然是一个尚未解决的环境问题,研究在水位波动条件下BTEX在土壤介质中的运移过程是充分了解BTEX对水环境影响的前提.本实验以甲苯为污染物,建立了土壤水环境中有机污染物运移实验模型,并通过控制砂柱饱和-非饱和状态转化来实现土壤所处环境(水位波动条件或饱水条件)的不同,对比研究了两种条件对污染物运移和相关的水文地球化学特征的影响.利用中砂、细砂、含10%黏土的细砂等3种土壤介质的实验数据对实验模拟进行验证.结果显示,在水位波动条件下中砂、含10%黏土的细砂介质中甲苯的衰减速率(6.4 mg·L~(-1)·d~(-1)、5.3 mg·L~(-1)·d~(-1))均大于饱和条件下甲苯的衰减速率(0.57 mg·L~(-1)·d~(-1)、0.59 mg·L~(-1)·d~(-1)).水位波动条件对水环境电导率没有影响,但甲苯的加入使水环境的pH升高.甲苯和地下水位波动的共同作用推迟了地下水环境中NO_3~-、SO_4~(2-)和NO_2~-达到平衡的时间.     

有机污染物在土壤—水体系中的分配理论

介绍了有机污染物在土壤－水体系中的分配理论，该理论认为有机污染物主要被土壤有机质以非吸附的方式所吸收，所以多种污染物被同叶吸收时不存在竞争作用，而且吸收量受到土壤有机质和有机污染物分子极性的影响。有机污染物在土壤有机质－水体系中的分配系数，主要与其水溶性有关。     

有机污染物在土壤—水体系中的分配理论

介绍了有机污染物在土壤—水体系中的分配理论。该理论认为有机污染物主要被土壤有机质以非吸附的方式所吸收，所以多种污染物被同时吸收时不存在竞争作用，而且吸收量受到土壤有机质和有机污染物分子极性的影响。有机污染物在土壤有机质—水体系中的分配系数，主要与其水溶性有关。     

稀土元素在土壤中迁移、转化模型的建立及验证

建立了稀土在褐土土壤中迁移、转化模型，定量评价稀土在土壤中的迁移、转化过程。模型包括土壤中稀土化学热力学平衡体系、土壤水分物理形状和土壤剖面的稀土通量。在中国农业大学内进行了田间实验，对模型进行了验证，模拟值与实测值能很好的拟合。     

基于有机污染物生物有效性的土壤环境质量基准的探讨

我国的土壤污染日益严重,由于污染物对土壤生物产生的毒性效应与其生物有效态含量相关,以污染物总量为指标的土壤环境质量标准已无法满足当前土壤管理的需求,亟需开展以生物有效性为基础的土壤环境质量基准的研究工作。目前对土壤中重金属的生物有效性的研究较为深入,但是针对有机污染物的土壤生物有效性研究相对匮乏。本研究综述了有机污染物在土壤中的结构形态、吸附吸收和迁移转化,以及影响土壤中有机污染物生物有效性的关键因素。从我国有机污染物的污染现状、土壤类型分布情况,以及物种选择3个方面对基于生物有效性的土壤环境质量标准/基准的制定进行探讨,以期为我国根据国情制定适合本土特征的生态安全土壤质量标准提供借鉴。     

我国环境化学研究的进展

本文综合介绍了二十年来我国环境化学研究的发展概况。在环境分析化学方面包括了环境分析监测方法、标准参考物质、环境分析方法、形态分析、采样技术与分析测试仪器化等方面。环境污染化学包括了有关大气、水体和土壤环境中化学问题的研究，着重对大气污染物表征、迁移和转化、化学模式和重金属、有机物的水环境化学、水环境中金属烷基化以及土壤中农药等环境化学研究。有关污染生态效应中的化学集中介绍了硒与地方病环境因素关系有     

持久性有机污染物环境多介质空间分异模型研究进展

环境多介质空间分异模型能够对持久性有机污染物(POPs)在环境多个介质中空间尺度上的迁移转化和分配过程进行准确、细致和接近真实的描述,是进行POPs的环境多介质归趋模拟和环境风险评价的重要工具.将环境多介质空间分异模型分为环境多介质质量平衡空间区划模型和大气化学传输模型,对目前几种常用的环境多介质空间分异模型GLOBO...     

污水土地处理磷污染物迁移转化模拟讨论分析

根据磷在土壤中的迁移转化机理，进行了以土柱试验为基础的“污水土地处理条件下磷的迁移转化模拟试验”，总结了污水中的磷在土壤中迁移转化的规律，提出了定量模拟这一规律的迁移转化联合模型。联合模型为研究磷在土壤中的运动提供了定量化依据，避免了已有研究中将迁移和转化割裂研究造成的误差，丰富并完善了不同形态磷的迁移转化模型。     

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.     

Representation of the world's biophysical conditions by the global protected area network

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.     

Quantitative composition of the defensive secretion ofBledius species (Coleoptera: Staphylinidae: Oxytelinae) is adapted to naturally occurring predators

Summary The adaptation of defensive secretions to their target organisms was examined for the abdominal gland secretions ofBledius furcatus, B. spectabilis andB. arenarius. Therefore the target organisms of the secretion of theseBledius species (i.e. their predators) had to be identified. At the collection sites examined these were the earwigLabidura riparia, the antCataglyphis bicolor, the flyLispe candicans, different carabids of the generaPogonus, Dichirotrichus, Dyschirius, Bembidion andCalathus and the wading birdsHaematopus ostralegus andCalidris alba. The secretion of the abdominal glands contains the toxin ptoluquinone dissolved in either-dodecalactone and 1-undecene (B. furcatus andB. spectabilis) or in octanoic acid and octyloctanoate (B. arenarius). The ratio of these solvents is species-specific. Application experiments using some of the natural insect predators (L. riparia, C. bicolor, Pogonus, Di. gustavii, Dyschirius) revealed that these solvent ratios provided a more effective deterrent than other possible ratios. Thus by combining the solvents in certain ratios, the capability of cuticular penetration and therefore the effectiveness of the defensive secretions are adapted to their natural targets.     

Democracy versus development: New urban debates

The politics of development includes subtexts of choice, as underpinned by community consensus (or lack of it), against the larger backdrop of a liberal democracy, with its intricate power structures that influence the choice of concepts and often lead to complicity rather than consent. A dilemma exists between the understanding of field-level practitioners and that of academics, whose understandings of progress differ. Progress can (and often does) imply long-term change across generations whereas development is often more a matter of crisis management and delivering tangible results to end-users. This makes it a bone of contention across political systems, irrespective of local or global dynamics. Development can emerge as a tool to be wielded for power and further political mileage at the expense of progress. Progress cannot be studied as a counterpoint to development as the sense of history is often missing in development interventions. Development tends to be piecemeal as its very logic often stems from the rationale of power. This is not to suggest, however, that development is only about politics; it is definitely more than the politics of everyday life and involves all of civil society that requires its critical and immediate attention. In this sense, it has become a priority for politicians with an underlying agenda designed to out-manouevre dissent and all statements of protest.     

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.     

A framework to measure the wildness of managed large vertebrate populations

As landscapes continue to fall under human influence through habitat loss and fragmentation, fencing is increasingly being used to mitigate anthropogenic threats and enhance the commercial value of wildlife. Subsequent intensification of management potentially erodes wildness by disembodying populations from landscape-level processes, thereby disconnecting species from natural selection. Tools are needed to measure the degree to which populations of large vertebrate species in formally protected and privately owned wildlife areas are self-sustaining and free to adapt. We devised a framework to measure such wildness based on 6 attributes relating to the evolutionary and ecological dynamics of vertebrates (space, disease and parasite resistance, exposure to predation, exposure to limitations and fluctuations of food and water supply, and reproduction). For each attribute, we set empirical, species-specific thresholds between 5 wildness states based on quantifiable management interventions. We analysed data from 205 private wildlife properties with management objectives spanning ecotourism to consumptive utilization to test the framework on 6 herbivore species representing a range of conservation statuses and commercial values. Wildness scores among species differed significantly, and the proportion of populations identified as wild ranged from 12% to 84%, which indicates the tool detected site-scale differences both among populations of different species and populations of the same species under different management regimes. By quantifying wildness, this framework provides practitioners with standardized measurement units that link biodiversity with the sustainable use of wildlife. Applications include informing species management plans at local scales; standardizing the inclusion of managed populations in red-list assessments; and providing a platform for certification and regulation of wildlife-based economies. Applying this framework may help embed wildness as a normative value in policy and mitigate the shifting baseline of what it means to truly conserve a species.     

Sexual Predators,Energy Development,and Conservation in Greater Yellowstone

Abstract: In the United States, as elsewhere, a growing debate pits national energy policy and homeland security against biological conservation. In rural communities the extraction of fossil fuels is often encouraged because of the employment opportunities it offers, although the concomitant itinerant workforce is often associated with increased wildlife poaching. We explored possible positive and negative factors associated with energy extraction in the Greater Yellowstone Ecosystem (GYE), an area known for its national parks, intact biological diversity, and some of the New World's longest terrestrial migrations. Specifically, we asked whether counties with different economies—recreation (ski), agrarian (ranching or farming), and energy extractive (petroleum)—differed in healthcare (gauged by the abundance of hospital beds) and in the frequency of sexual predators. The absolute and relative frequency of registered sex offenders grew approximately two to three times faster in areas reliant on energy extraction. Healthcare among counties did not differ. The strong conflation of community dishevel, as reflected by in‐migrant sexual predators, and ecological decay in Greater Yellowstone is consistent with patterns seen in similar systems from Ecuador to northern Canada, where social and environmental disarray exist around energy boomtowns. In our case, that groups (albeit with different aims) mobilized campaigns to help maintain the quality of rural livelihoods by protecting open space is a positive sign that conservation can matter, especially in the face of rampant and poorly executed energy extraction projects. Our findings further suggest that the public and industry need stronger regulatory action to instill greater vigilance when and where social factors and land conversion impact biological systems.     

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.     

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.