蒙脱石吸附Cr3+、Cd2+、Cu2+、Pb2+、Zn2+的研究:pH值和有机酸的影响

粘土具有良好的离子交换和吸附特性，常被用作垃圾填埋场的衬层，吸附垃圾渗滤液中的氨氮及重金属离子，防止污染土壤和地下水。研究了pH值对蒙脱石吸附Cr^3 、Cd^2 、Cu^2 、Pb^2 和Zn^2 等五种重金属离子的影响，以及有化学络合剂EDTA和几种有机酸存在条件下，蒙脱石吸附Cr^3 、Cd^2 、Cu^2 、Pb^2 和Zn^2 五种重金属离子的效果。为了接近自然吸附状态，实验采用了离子交换柱进行连续吸附。结果表明，pH值对Cu^2 、Pb^2 和Cu^2 的吸附率影响极大；化学络合剂以及有机酸的存在降低了各重金属离子的吸附率，影响的强弱(设其符号为y)顺序为Y(Pb^2 )≤y(Cd^2 )≤y(Zn^2 )≤y(Cu^2 )≤y(Cr^3 )。     

花生壳吸附Pb^2＋、Cu^2＋、Cr^3＋、Cd^2＋、Ni^2＋的动力学和热力学研究

以花生壳为生物吸附剂,通过序批式实验研究了吸附剂投量、吸附时间、金属离子初始质量浓度、吸附温度对吸附金属离子的影响,探讨了花生壳吸附的动力学及热力学特性。结果表明,准二级动力学方程能很好地描述花生壳对Pb^2＋、Cu^2＋、Cr^3＋、Cd^2＋、Ni^2＋的吸附过程。Langmuir模型和Freundlich模型均能较好地描述花生壳对5种重金属离子的等温吸附过程,而Langmuir模型拟合的线性更好。Pb2＋、Cu2＋、Cr3＋、Cd2＋、Ni2＋5种金属离子的最大吸附量分别是32.25、7.09、3.82、2.95、2.22 mg.g-1,花生壳可用于处理低质量浓度多种重金属混合的废水。热力学研究表明,花生壳对5种金属离子的吸附具有自发、吸热和熵增的特性。     

2,4-D对铜在蒙脱石上吸附与释放的影响

研究了在2，4-D的影响下，Cu^2 在蒙脱石上的吸附与脱附行为．结果表明．有2，4-D存在时，Cu^2 在蒙脱石上的吸附低于单纯Cu^2 的吸附，而当蒙脱石先吸附2,4-D后再吸附Cu^2 (连续吸附)时，Cu^2 的吸附比二者同时存在时(同时吸附)的效果好，表明两种吸附质间存在竞争吸附．研究还表明，所有的吸附过程都符合Langmuir和Freundlich吸附等温模型．在有2，4-D同时存在时，Cu^2 的脱附最大，可达30％；而单纯Cu^2 在蒙脱石上的吸附似乎是不可逆的，脱附百分比最小。     

干污泥及其改性物对染料的吸附

以城市污水处理厂剩余活性污泥为原料，制取干污泥、热解污泥和改性污泥作为吸附剂，对直接深棕M和酸性媒介棕RH等染料进行了吸附试验研究。研究结果表明，干污泥及其改性物对染料的吸附能够用Lagergren二级动力学方程描述，该吸附遵循二级动力学规律。直接深棕M的吸附符合Freundlich型等温吸附，易于吸附在改性污泥和热解污泥上；酸性媒介棕RH的吸附既符合Freundlich方程，也可用Langmuir吸附等温方程描述。干污泥和热解污泥对两种染料的吸附过程中存在颗粒内扩散效应。在试验条件下，相对吸附量依改性污泥、热解污泥、干污泥的顺序减少，因此，活性污泥经过改性后能够提高对所研究的染料的吸附能力。     

亚甲基蓝在缺氧活性污泥上的吸附平衡和动力学

为了考察缺氧活性污泥对染料的吸附性能和吸附机理,以缺氧活性污泥作为吸附剂,亚甲基蓝作为吸附质进行等温吸附试验。结果表明:亚甲基蓝在缺氧活性污泥上的吸附遵循准二级速率方程,吸附方式为化学吸附;吸附行为符合Langmuir和Redlich-Peterson吸附等温式,为单分子层吸附,理论最大吸附量9.25 mg/g;亚甲基蓝分子在污泥颗粒内扩散动力学曲线存在线性部分,说明吸附过程存在污泥颗粒微孔内扩散效应。     

生物吸附剂-海黍子吸附镍

采用生物吸附剂-海黍子对重金属镍离子进行吸附，做了动力学实验，得到了海黍子吸附镍的动力学方程。研究了溶液的pH值，初始Ni^2 浓度等因素对Ni^2 的吸附特性的影响，得到最佳pH值4～6及最大吸附量0．8283mmo1／g，并用Langmuir和Freundlich方程对吸附等温线进行了拟合，用Langmuir方程拟合相关系数R^2达0．999以上。     

活性污泥对水中低浓度无机汞和甲基汞的吸附特性

为研究活性污泥对汞的吸附特性,本研究以焦作市第一污水处理厂活性污泥为原料,制取干污泥作为吸附剂,开展了干污泥对水中低浓度(ng·L~(-1))无机汞和甲基汞的吸附动力学实验和等温吸附实验.吸附动力学实验结果表明,干污泥对无机汞的吸附表现为吸附量在前30 min急剧增加,30 min后缓慢增加直至平衡.干污泥对甲基汞的吸附速率远远快于无机汞,在1 min内基本达到吸附平衡状态.干污泥对无机汞和甲基汞的吸附过程均符合Pseudo-second Order模型,属于化学吸附过程.等温吸附实验结果表明,干污泥对无机汞和甲基汞的吸附量与平衡浓度呈近似线性关系,等温线与Henry方程拟合较好.干污泥对水中无机汞和甲基汞的去除率随着初始汞浓度的增加呈现上升趋势,达到一定浓度后趋于稳定.     

无花果曲霉对Cu^2＋吸附的研究

采用生物吸附法,研究了经过预处理的无花果曲霉对Cu^2 吸附行为与影响吸附的主要因素,具体包括菌丝球与Cu^2 接触反应时间、Cu^2 浓度、原初pH值3个方面。结果表明：该菌丝球在吸附进行5min时,吸附量已达量2．855mg/g,在吸附进行4h以后趋于平衡。最佳pH范围为4．0－5．0,Cu62 浓度在20－100mg/L范围内吸附量为2．763－4．713mg/g,而吸附率却为32．31％－9．54％。其吸附行为在一定的温度和一定浓度范围内较好地符合Langmuir吸附等温模型。     

不同类型土壤对重金属的吸附特性

为了解重金属在土壤中的迁移转化规律,为确定土壤环境容量和治理土壤重金属污染提供理论依据,采用室内试验方法研究了采自山东的棕壤、黑龙江的黑土、陕西的黄棕壤和山西的褐土吸附Cu2 、Pb2 和Cd2 的特性及溶液pH、外加腐殖酸、溶液中重金属初始含量对吸附的影响.由振荡平衡法进行吸附试验,原子吸收分光光度法测定平衡溶液中重金属的吸光度值.试验结果表明:随着溶液中Cu2 、Pb2 和Cd2 含量的增大,4种土壤对Cu2 、Pb2 和Cd2 的吸附量逐渐增大.溶液pH值对土壤吸附重金属的影响因土壤性质和重金属特性的不同而不同.加入腐殖酸,4种土壤对Cu2 、Pb2 和Cd2 的吸附量明显减少.不同吸附模型拟合结果表明,4种土壤对Pb2 的吸附等温线都符合 Langmuir 方程和Freundlich方程,对Cu2 吸附等温线拟合的Langmuir 方程和Freundlich方程的相关性不理想,对Cd2 吸附等温线拟合符合Freundlich方程.     

低品位硅藻土吸附重金属的研究

硅藻土是一种生物硅质沉积岩,具有较大的比表面积,在工业上常用作吸附材料。但低品位硅藻土不利于直接加工利用,在矿产开发中常被忽视或丢弃。为更好地开发和利用低品位硅藻土,采用静态吸附实验研究了低品位硅藻土吸附四种重金属离子（Pb2＋、Zn2＋、Cu2＋、Cd2＋）的动力学规律,用伪一阶、伪二阶模型及粒内扩散模型（Weber和Morris模型）对其吸附过程进行拟合,结果表明,硅藻土对四种重金属离子的吸附均符合伪二阶动力学模型。同时,实验也研究了硅藻土吸附Pb2＋、Zn2＋、Cu2＋、Cd2＋的热力学,并分别用Langmuir、Freundlich和Dubinin-Radushkevich（D-R）方程进行拟合。结果表明,Freundlich和D-R方程都能很好地描述硅藻土对Pb2＋、Zn2＋、Cu2＋、Cd2＋的吸附热力学。并且硅藻土对这四种重金属离子的吸附均为吸热反应。     

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.     

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.     

Comparison of the insecticidal effects of water extracted and intact aromatic plants onAcanthoscelides obtectus,a bruchid beetle pest of kidney beans

Summary Acanthoscelides obtectus (Say) is one of the most damaging pests of kidney beans,Phaseolus vulgaris L. worldwide. However, aromatic plants from the families Lamiaceae, Lauraceae, Myrtaceae and Poaceae can protect kidney beans by direct or delayed insecticidal effect, through increased adult mortality and inhibition of beetle reproduction (both oviposition and adult emergence). The efficiency of hydrodistillated and intact plants fromThymus vulgaris andT. serpyllum, Mentha piperata, Rosmarinus officinalis, Satureia hortensis, Eucalyptus globulus, Laurus nobilis, Origanum vulgare, andCymbopogon nardus was compared. For both extracts,Origanum vulgare had the best effect. The insecticidal effect was induced by more than the essential oils because no significant difference was noticed between distilled and intact plants extract. Inhibition of reproduction was particularly important. These results suggest that lipidic as well as non lipidic, allelochemicals, such as phenolics, or non-protein amino-acids, or flavonoids may be involved in the toxicity of aromatic plants to this beetle.