固定化啤酒酵母制剂去除水中重金属离子

研究了天津某啤酒厂啤酒酵母废菌丝制备的生物吸附剂对水中重金属Cu2+、Zn2+和Cd2+的吸附作用;另外,为了增加其实用性,对海藻酸盐固定化啤酒酵母制剂去除重金属的效果及洗脱再生条件进行了研究。结果明,啤酒酵母制剂有较好的吸附能力,5 min就可以达到很高的吸附效率。Langmuir方程可对Cu2+、Zn2+和Cd2+的等温吸附过程进行很好的描述。当pH为5～6时,Cd2+、Zd2+和Cd2+的吸附效率最大,上除率在90％以上。啤酒酵母制剂固定化后,对Cu2+的最大理论吸附量达到15．74 mg/g。用HCl可对固定化制剂进行洗脱和再生。     

人居生活废弃物生物黑炭对水溶液中Cd2+的吸附研究

以人居生活废弃物生物黑炭为材料,探讨生物黑炭对Cd2+的吸附动力学及热力学特性,通过平衡吸附法研究吸附时间、Cd2+初始质量浓度、吸附剂投加量、溶液pH值以及黑炭粒径对Cd2+吸附率的影响.结果表明,吸附时间为2h时基本达到吸附平衡,准二级动力学方程能很好地描述生物黑炭对Cd2+的吸附过程.Langmuir模型能较好地描述生物黑炭对Cd2+的等温吸附过程,根据该模型模拟得到25℃条件下Cd2+最大吸附量为6.22mg·g-1.Cd2+去除率随生物黑炭投加量的增加而增大;生物黑炭对Cd2+吸附量随其粒径减小而增大;溶液初始pH值为4.0～7.5时,pH值变化对Cd2+吸附量的影响不显著.采用人居生活废弃物生物黑炭去除水溶液中Cd2+时,控制溶液Cd2+初始质量浓度30mg·L-1,粒径小于0.25 mm,投加水平8g·L-1,反应温度25℃,反应时间1～2h,Cd2+去除率可达80％.人居生活废弃物生物黑炭可以作为去除污染水体中Cd2+的吸附剂.     

黑曲霉吸附弱酸性艳蓝RAWL机理研究

考察了黑曲霉对染料吸附性能的pH响应模式,红外光谱表征了菌体表面的主要官能团组成,化学修饰定量研究了不同官能团的染料吸附贡献.结果显示,在低pH条件下,菌体表现出最优的染料吸附特性:随着pH值由2.0升至6.0,染料吸附量由39.6mg/g降至9.3mg/g.菌体表面含有氨基、羧基和磷酸根.高pH下,羧基和磷酸根电离导致菌体表面带负电并与染料发生静电斥力,使得染料吸附量下降;低pH下,氨基的质子化使得菌体带正电并通过静电吸引提高染料吸附.甲基化氨基在酸性条件下仍然可以质子化,故氨基甲基化修饰后染料吸附性能不变;乙酰化氨基在酸性体系中失去质子化能力,乙酰化修饰菌体染料吸附性能下降51.6%.氨基质子化引起的菌体正电性和染料负电性之间的静电引力是染料吸附的重要机制.图6参10     

磁性海泡石表面零电荷点和吸附Cd~（2＋）的特性

采用惰性电解质滴定法和静态吸附实验,研究了磁性海泡石表面零电荷点和吸附Cd2＋特性.实验结果表明,海泡石经过磁改性后所对应的pHpzc值由8.0升高到8.5,吸附体系pH的提高,有利于对重金属阳离子Cd2＋的吸附.在pH值大于3时,磁性海泡石对Cd2＋吸附量和去除率随pH值的升高而增大且趋于稳定,其吸附量为16.10 mg.g-1,约为海泡石的3.9倍,去除率为98%,约为海泡石的2.2倍.磁性海泡石对Cd2＋的吸附量与离子强度有较大的相关性,随离子强度的增加而减小;对Cd2＋的吸附量随反应温度的升高而增加,吸附等温式符合Langmuir方程.吸附机理以表面配合吸附和表面沉淀为主.     

酿酒酵母对Cu2+生物吸附机制的研究

采用废啤酒酵母分析了pH值、加菌量等影响啤酒酵母吸附Cu2 的主要因素,结果表明:pH4.5,吸附时间1—1.5h,加菌量0.01g·ml-1为最佳吸附条件;酵母对Cu2 的吸附符合Langmuir模型,表现为单分子层吸附;酵母菌细胞壁表面的—COOH,—NH3以及脂肪在其吸附铜离子时起着重要作用,NaOH处理的酵母吸附能力大大增加.     

老化作用对水稻秸秆生物炭吸附Cd(Ⅱ)能力的影响

环境变化使生物炭材料发生老化作用,老化后的生物炭是否仍具有较强的吸附能力是评价生物炭对Cd修复的长期稳定性的重要指标.本文采用自然老化(Spontaneous aging,SPON),冻融循环老化(Freeze-thaw cycles aging,FTC)和高温老化(High temperature aging,HT)的方法对水稻秸秆生物炭进行2个月的人工加速老化,运用扫描电镜(SEM-EDS)、元素分析仪、傅里叶红外光谱分析仪(FTIR)研究老化作用对秸秆生物炭材料的影响,再通过等温吸附实验研究生物炭老化前后对Cd吸附性能特征的变化.结果表明,老化作用使生物炭材料局部发生破碎,增加了生物炭表面O/C比.老化作用显著影响秸秆生物炭表面的官能团,降低了生物炭表面—OH的数量,增加了CO、—COOH和Si—O—Si的数量,出现了C≡C键,可为Cd提供更多的吸附位点.等温吸附试验进一步证明了老化后的生物炭提高了对Cd(Ⅱ)的吸附性能.与生物炭原样相比,冻融循环老化、高温老化、自然老化使生物炭的Cd最大吸附量分别达到了26.49、33.30、23.40 mg·g~(-1),增加了27.8%,60.7%,12.9%.本研究表明老化作用改变了生物炭材料的表观结构和官能团,增强了对Cd(Ⅱ)的吸附能力,因此生物炭对Cd的修复具有一定的长期稳定性.     

固定香菇菌柄废弃物对二元溶液中Cd(Ⅱ)的竞争性吸附

利用聚乙烯醇-海藻酸钠(PVA-SA)固定香菇(Lentinus edodes)菌柄废弃物作为生物吸附剂吸附溶液中的Cd2+,吸附过滤后的溶液用原子吸收光谱仪(AAS)测定Cd2+的浓度.结果表明,一元溶液中固定香菇菌柄废弃物吸附Cd2+适宜的pH值范围为4～7,比自由态香菇粉的(pH5～7)广;二元溶液中随着pH值的增加,Cd2+的吸附率有线性增加的趋势;当固定Cd2+浓度为10mgg-1,变化干扰离子Cu2+或Pb2+(0～30mgg-1)时,吸附剂对Cd2+的吸附明显降低;分别用Langmuir、Freundlich、Dubinin-Radushkevich(D-R)和Langmuir-Freundlich等温吸附模型对一元和二元溶液中Cd2+的等温吸附过程进行拟合,结果表明,Langmuir吸附模型能较好地拟合一元溶液和Cd2+-Pb2+二元溶液中Cd2+的等温吸附过程,相关系数R2分别为0.9981和0.9291.D-R模型能较好地拟合Cd2+-Cu2+二元溶液中Cd2+的等温吸附过程,相关系数R2为0.9623.     

氮改性对生物炭理化性质的影响及其对废水中铜离子的吸附特性

原状生物炭对废水中污染物的去除效果有限,改性是提高其吸附能力的重要途径.本文以水稻秸秆为对象,尿素为改性剂,在700℃无氧热解条件下分别制备了原状秸秆生物炭（RSBC）和氮改性秸秆生物炭（N-RSBC）,采用扫描电子显微镜（SEM）、比表面积分析仪（BET）、元素分析仪（EA）、Zeta电位、X射线衍射（XRD）、傅里叶红外光谱（FTIR）以及X射线光电子能谱（XPS）对RSBC和N-RSBC的形貌、比表面积、元素组成、矿物类型和官能团进行表征,考察溶液初始pH值、离子类型和离子强度对生物炭吸附Cu²⁺的影响,并结合吸附等温线和吸附动力学实验、吸附后表征结果探究生物炭对废水中Cu²⁺的吸附性能和机理.结果表明,氮改性导致了生物炭的比表面积和孔体积的降低,而生物炭的官能团类型却更加丰富,特别是含氮官能团.当溶液初始pH值从2.0增加到6.0,生物炭对于Cu²⁺的去除率逐渐增加.对RSBC而言,Na⁺、K⁺、Ca²⁺、Mg2+的存在能略微增加其对Cu^...     

好氧颗粒污泥对水溶液中酸性淡黄2G的生物吸附

利用好氧颗粒污泥对酸性淡黄2G溶液进行吸附脱色研究,考察了pH值、吸附剂用量、初始酸性淡黄2G的浓度、温度以及NaCl浓度对吸附过程的影响.实验结果表明,吸附过程对溶液pH值具有很高的依赖性,其最佳pH值为2.0.Temkin等温线在整个实验染料浓度范围内能够很好地描述吸附过程.吸附动力学符合准二级动力学模型.内部扩散和边界层扩散都可能影响生物吸附速率.热力学分析表明,吸附过程是一个自发的放热过程.采用FTIR分析的结果进一步揭示了颗粒污泥上官能团(如胺基、羧基和羟基等)可能是染料生物吸附的活跃结合位点.这些结果表明,好氧颗粒污泥可以作为吸附剂以去除水中的酸性淡黄2G。     

脱除H2S用铁/凹凸棒石的优化制备及性能评价

用均相沉淀法制备了铁/凹凸棒石复合物用于H2S的脱除.考察了反应物配比、反应时间和反应温度对铁转化率、体系pH值和Fe3+浓度变化的影响;用透射电镜对不同条件制得的脱硫剂的形貌进行了表征,以模拟工业尾气为气源做H2S动态吸附实验.结果表明,体系pH值的上升是Fe3+完全沉淀的标志;体系OH-浓度主要受反应温度的影响,升高反应液温度有利于提高铁转化率,而反应物配比对其影响不大;升高温度会使沉淀速度过快,引起凹凸棒石表面铁分散性下降,形貌发生变化,导致脱硫剂性能下降.     

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.