石油烃污染土壤联合修复技术研究进展

随着石油的开采和使用,土壤石油烃污染的问题已经十分严峻,研究绿色、高效、低成本的修复技术对于污染土壤修复具有重要意义.通过总结了物理、化学和生物修复技术对石油烃污染土壤的修复效果、影响因素以及优缺点,并针对以上技术的局限性,归纳整理电动-化学氧化、电动-微生物修复、表面活性剂淋洗-生物修复、预氧化-生物修复、植物-微生...     

基于专利申请分析的有机磷农药污染土壤修复技术研究进展

有机磷农药（organophosphorus pesticide,OPP）的生产量和使用量高,但回收率与利用率低,且毒性较强,土壤累积量大、污染面积大,已严重威胁人类健康与生态系统平衡,因此OPP污染土壤的修复是健康土壤行动的重要内容.以专利分析为切入点,分析我国2010-2021年OPP污染土壤修复相关申请专利,梳理该方面技术发展情况,综述生物、物理、化学主流技术修复OPP污染土壤现状.分析发现,专利时空分布、隶属分布等反映了该领域技术的现状与需求,利用磷酸水解酶、木霉属、假单胞菌属、芽孢杆菌属等微生物对OPP进行水解、共代谢的生物修复技术,应用生物刺激、化学氧化、光催化等化学修复技术,以及联合修复方法为当前OPP污染土壤的主流修复方法.现有修复技术受环境、修复材料与污染土壤的相互作用变化等影响,未来仍需进一步研究OPP在土壤-生物系统中的降解作用及其物理、化学、生物降解机理,明确OPP与其代谢产物的运输、扩散、转移途径;并将理论研究应用于实际修复工程,加大原位修复技术研发力度,根据污染场地环境、土著微生物、土壤污染程度选择合适的修复技术方案,以促进有机磷污染土壤修复行业的发展.（图...     

化学强化植物修复复合污染土壤研究进展

近年来,土壤复合污染问题日趋严峻,且修复难度往往较大.在复合污染土壤众多修复技术中,植物修复因成本低、易实施、环境友好等特点而颇具潜力.然而植物修复存在周期长、效率低的局限性.因此,围绕植物开展的联合强化修复技术研究,成为复合污染土壤治理修复的新途径,其中化学强化植物修复技术研究备受关注.本文综述了化学强化植物修复3种复合污染土壤的效果,对比分析了不同化学强化措施的作用特点和异同,并对该技术的研究方向提出了展望.     

多孔介质中三氯乙烯的非线性吸附-对流-弥散模型

研究三氯乙烯(TCE)在含水层中的迁移转化规律,对评价其在环境中的影响、预测其在环境中的行为规律及确定相应的修复技术有着重要的意义.TCE在细砂中的等温吸附规律研究采用批试验和模拟柱试验方法.批试验结果采用四种不同的非线性等温吸附模型进行拟合.结果显示,Linear-Langmuir-Freundlich (LLF) 模型的拟合效果最佳,且该模型能较好地描述表面吸附和分配作用.利用经典对流扩散模型,将以KCl为示踪剂的柱试验结果采用非线性最小二乘法反演模拟柱中的纵向弥散度;利用非线性吸附对流扩散模型,将TCE的模拟柱试验结果采用遗传算法反演吸附参数;结果显示Langmuir等温吸附模型描述柱试验中的吸附模式最好.即批试验与柱实验中的吸附模式是不同的.该结论表明必须重新审视非平衡吸附理论在运移模型中的适用性,以及该理论适用的前提条件.在试验结果和模型反演获得的参数基础上确定的TCE在多孔介质中运移的一维非线性吸附-对流-扩散模型,能够很好地揭示TCE在多孔介质中的运移规律,且模型中的阻滞系数是质量浓度的非线性函数.     

土壤有机污染物生物修复技术研究进展

现代农业的发展改变了自然界的原有状况,为追求高产而大量使用的化肥、农药导致土壤有机物污染日趋严重。此外,工业生产、石油开采、交通运输、畜禽养殖及居民生活等也产生了大量有机污染物,使土壤有机物污染进一步加剧,土壤有机物污染的修复日益迫切。土壤污染修复是指通过物理的、化学的和生物的方法,吸收、降解、转移和转化土壤中的污染物,使污染物浓度降低到可以接受的水平,或将有毒有害的污染物转化为无害物质的过程。包括污染土壤的物理修复技术、化学修复技术以及生物修复技术3种方式。在污染土壤修复技术中,生物修复技术因其安全、无二次污染及修复成本低等优点而受到越来越多的关注。因污染物修复主体的不同,有机污染物污染土壤生物修复技术可分为植物修复技术、动物修复技术、微生物修复技术及其联合修复技术。污染土壤微生物修复技术是土壤污染生物修复的重要技术之一,是最具应用和发展前景的生物修复环保技术。文章重点阐述了国内外有机污染物污染土壤的生物修复技术及其原理、取得的研究进展及存在的优缺点,并对污染土壤的动物修复技术研究进行了初步展望,可为土壤有机污染物的生物修复研究提供参考。     

土壤重金属污染生物修复的研究进展

土壤重金属污染的生物修复是污染整治的重要手段之一 ,是目前世界范围内的研究热点 ,亦是目前仅见的土壤污染治理的环境友好技术。主要评述了重金属污染土壤的植物修复的原理、类型与技术 ,植物修复的优点 ,微生物修复等进展情况。并对今后的研究重点进行了简要的讨论     

土壤重金属污染生物修复的研究进展

土壤重金属污染的生物修复是污染整治的重要手段之一,是目前世界范围内的研究热点。亦是目前仅见的土壤污染治理的环境友好技术,主要评述了重金属污染土壤的植物修复的原理、类型与技术植物修复的优点,微生物修复等进展情况。并对今珀的研究重点进行了简要的讨论。     

农田土壤重金属污染状况及修复技术研究

重金属污染因具有毒性、易通过食物链在植物,动物和人体内累积,对生态环境和人体健康构成严重威胁。随着工业快速发展、农药及化肥的广泛使用,农田土壤重金属污染越来越严重,研究农田土壤重金属污染现状及修复技术对农产品安全具有重要意义。综合国内外农田土壤重金属污染状况,农田土壤重金属污染主要来源于固体废弃物堆放及处置、工业废物大气沉降、污水农灌和农用物质的不合理施用。该文综述了国内外有关农田重金属污染土壤修复技术（物理修复、化学修复、生物修复、农业生态和联合修复）的研究进展,并针对各种修复方法,阐述了其原理、修复条件、应用实例及其优缺点,重点论述了植物修复的机理和应用,提出了草本与木本联合修复可有效提高农田土壤重金属复合污染的修复效率,为农田土壤土壤重金属复合污染修复提出了新的途径。最后在对已有研究分析的基础上,提出了联合修复技术（如生物联合技术、物理化学联合技术和物理化学-生物联合技术）可以在一定程度上克服使用单一修复手段存在的缺点,可提高复合污染的修复效率、降低修复成本,未来应深入探索联合修复技术间的相互作用机理,以期为农田土壤重金属综合治理与污染修复提供科学依据。     

污染土壤中菲的修复技术研究进展

菲是多环芳烃中的代表性物质,具有"三致"效应,而且菲的蒸汽压小,辛醇-水分配系数高,生物可利用性低,是一种持久性有机污染物。随着化石燃料的大量使用,受菲污染的土壤越来越多,研究菲的修复技术对污染土壤的再利用具有重要意义。结合目前国内外研究进展,综述了污染土壤中菲的修复方法,包括物理修复、化学修复和生物修复。针对各种修复方法,阐述了其原理、修复条件、实例应用和优缺点,重点论述了植物修复和微生物修复方法的降解机理和应用,分析了微生物性质,包括氧、营养物、温度、土壤理化性质、共存污染物等环境因素对生物降解的影响。由于溶解性的菲有较好的迁移转化能力,因此表面活性剂的助溶作用适用于各种修复方法,选择合适的表面活性剂可以提高修复效果。在各种修复技术中,物理修复是通过物理技术实现菲的解吸与富集,无污染,但是去除率低;化学修复是使用氧化剂将菲氧化分解成无毒易降解的小分子物质或通过添加化学淋洗剂增加菲的溶解性,提高迁移转化能力,用时短,但是引入其他试剂,容易造成二次污染;植物修复是通过植物的提取、降解和固定等过程实现菲的修复,尤其是植物的根际环境为微生物的生长提供有利的条件;微生物修复以菲可作为微生物生长的碳源为基础,在分解酶的作用下实现菲的降解,但是生物修复周期长,可利用的生物少,而且可能生成毒性更高的中间代谢产物。因此,寻找合适的修复物种,采用基因技术提高生物的修复能力或多法联用、取长补短可提高修复效率。最后,在共降解理论的基础上,结合重金属和有机污染物共存时,一种物质的存在对另一种物质的降解有促进作用,提出了协同降解的概念,寻求对多种污染物有协同降解或共降解作用的修复方法是今后发展的主要方向。     

污染土壤的修复技术研究进展

分析了当前我国严峻的土壤环境状况，并从重金属和有机污染物两个方面，全面介绍了当前污染土壤的各种修复技术，包括物理化学修复方法、植物修复方法和微生物修复方法等；对各种方法的修复原理、已取得的研究进展、存在的优缺点及其将来的发展趋势进行了较全面的综述和展望。文章认为，污染土壤修复将是一项非常具有挑战性同时又是一项非常有前途的修复技术，将会对人类健康和经济可持续发展发挥重要作用。     

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.     

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     

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).