间甲酚降解Citrobacter farmeri 的降解特性及代谢途径解析

考察了在不同温度、pH值、摇床转速、氮源等环境和营养条件下,间甲酚降解菌Citrobacter farmeri对降解速率和降解过程中反应液的TOC值、紫外吸收及酶活的变化.结果表明,Citrobacter,farmeri降解间甲酚的最适温度为35℃,培养基初始pH值为6.5-8.0,摇床转速为170 r·min~(-1),无机氮比有机氮和氨态氮比硝态氮更利于Citrobacter farmeri对间甲酚的降解;当间甲酚初始浓度低于375mg·l~(-1)时,Citrobacter farmeri降解间甲酚符合零级动力学方程;间甲酚初始浓度约为60 mg·l~(-1)时约4 h完全降解,TOG的去除率8 h内可达到77%,之后几乎不变;Citrobacter farmeri可完全降解约600 mg·l~(-1)的间甲酚,表现出高效与强耐受能力的结合.对酶活的测定发现,儿茶酚1,2-双加氧酶有明显增大,初步判断Citrobacter farmeri以邻位裂解的途径对间甲酚进行降解.     

Y-射线辐照催化降解水溶液中萘普生

利用^60co产生的y-射线辐照水溶液中萘普生,研究了萘普生的降解特性．通过测定辐射后萘普生的浓度,探讨了吸收剂量、溶液pH、不同添加物（H2O2,CO23-;t-BuOH）对萘普生降解效果的影响．结果表明,1一射线辐照能有效催化降解水溶液中的萘普生,降解过程符合准一级动力学方程．萘普生浓度为23．6mg·L^-1,吸...     

白腐菌Trametes hirsute对六氯苯的降解及其条件优化

在液体体系下,筛选了5株白腐菌,对六氯苯进行了降解研究,并优化了白腐菌Trametes hirsute TH对六氯苯的降解条件.结果表明,不同白腐菌均能降解六氯苯,其中白腐菌Trametes sp.TR对六氯苯降解率最高,达90.21%;而白腐菌T.hirsute TH对六氯苯降解率为87.08%,但生物量最高,达3.33 g/L.通过响应面法优化白腐菌T.hirsute TH降解六氯苯的条件,结果显示,转速、接种量和培养时间是影响六氯苯降解的主要因素.优化后的最佳条件为:转速125 r/min,菌丝接种量8%(V/V),培养时间2 d,温度28 ℃,pH为7.在优化条件下,2 d内白腐菌T.hirsute TH对浓度为10 mg/L的六氯苯降解率和降解量分别可达91.52%和2.288 mg L-1 d-1.图2表7参17     

高效异养硝化-好氧反硝化菌株TS-1筛选及降解特性

从实验室定向驯化的活性污泥中分离筛选出一株具有异养硝化-好氧反硝化功能的菌株TS-1.通过生理生化及16S r RNA基因序列鉴定其为脱氮副球菌,通过单因素和正交实验对其去除NH_4~+-N的最佳条件进行优化,并通过对比进一步探究其在不同氮源条件下对各形态无机氮的去除规律.结果表明该菌株最适碳源为丁二酸钠,最佳C/N为15,最佳接种量为5%,最适温度为30℃、p H为8.0.以初始浓度约为100 mg/L的NH_4~+-N、NO_3~--N和NO_2~--N分别为单一氮源时,菌株TS-1对各形态氮的去除率为97.49%、100%和95.94%;维持各形态氮初始浓度不变,将其两两混合时发现混合氮源中若包含NO_2~--N会使菌株OD_(600)值达到最大值所用时间延长,氮源中含有NH_4~+-N会降低菌株对其他形态氮源的去除率,以及NO_3~--N的添加会使菌株对NH_4~+-N的去除能力降低;3种形态氮源同时存在的条件下,该菌对各氮源去除能力由强至弱为NO_2~--NNH_4~+-NNO_3~--N.本研究从活性污泥中分离筛选出一株具有高效异养硝化-好氧反硝化功能的菌株TS-1,通过研究碳源、氮源、温度、p H得到了最佳降解条件,可为废水短程脱氮提供参考.(图9表4参37)     

嗜碱细菌降解木质素的复合碳源共代谢研究Ⅰ——复合碳源组合方式及氮源的选择

研究在碱性液体培养条件 (pH =1 0 .5)下 ,不同碳源组合方式对嗜碱木质素降解菌产酶及降解麦草木质素的降解率的影响。研究结果表明 ,在蔗糖 (第一碳源 ) +麦草木质素 (第二碳源 )的组合方式下 ,并将硝酸铵作为氮源且碳氮比为 1 :1 .2时 ,该菌株的产酶及降解能力效果理想。     

甲胺磷农药降解菌HS-A32的分离鉴定及降解特性

从长期受有机磷农药污染的土壤中分离到一株降解菌HS-A32,能以甲胺磷作为唯一的碳源和氮源生长.HS-A32菌降解甲胺磷的最适温度为30℃,最适pH值为7.0,甲胺磷的最适降解浓度为1 000 mg/L,降解率达82%.聚酰胺薄层色谱(TLC)可检测到降解产物中有NH4 生成.HS-A32菌能以多种碳、氮源生长,外加可利用的碳源和氮源能促进甲胺磷的降解.通过16S rDNA扩增、测序,运用BLAST检索分析,构建系统进化树.结合生理生化鉴定,初步确定HS-A32为不动杆菌属(Acinetobacter).HS-A32菌还能降解甲基对硫磷等多种有机磷农药.图6表1参14     

产酯酶B1海洋枯草芽孢杆菌C5发酵条件优化

为提高芽孢杆菌C5产酯酶B1的能力,采用响应面法对其发酵条件进行优化.首先通过单因素实验筛选氮源、碳源、接种量、起始发酵pH、装液量、发酵温度和转速这7个因素,当酶活达到最高值时,各单因素的值分别为氮源玉米浆30 mL/L,碳源麦芽糖35 g/L,接种量4%(φ),起始pH 7.0,装液量15 mL,培养温度36℃,转速在实验室现有条件下最高选择220 r/min;再通过Plackett-Burman(PB)设计法,评价了这7个因素对酯酶B1产量影响的大小,确定氮源玉米浆的浓度、发酵起始pH和发酵温度为酯酶产生的3个主要影响因素;利用中心组合设计(CCD)及SAS软件分析获得了主要因素的最优条件,即玉米浆浓度28.70 mL/L,起始发酵pH为7.10,发酵温度为35.8℃.预测最高酶活力为139.18U/mL,实验最终酶活达到138.40 U/mL,与原发酵条件相比提高了228.15%.其实验值与预测值基本相符,说明预测模型可应用于酯酶发酵条件的优化.     

一株杀扑磷高效降解菌的分离、鉴定及降解条件的响应面法优化

有机磷杀虫剂杀扑磷对防治蚧壳虫有特效,常用于柑橘类果树防治但其残留有毒有害,自然界降解速度比较缓慢.本研究分离并分类鉴定了能高效降解杀扑磷的菌株,进一步采用Box-Benhnken法设计3因素3水平的响应面试验优化降解条件.结果显示,从富集培养基中分离到了一株杀扑磷高效降解细菌MS1-2,经鉴定为膝形假单胞菌(Pseudomonas geniculata);单因素选择温度、NaCl浓度和pH,通过检测杀扑磷残留量对杀扑磷降解条件进行响应面优化,转速设置为100 r/min,接种量为0.4%时,温度和Na Cl浓度为主要影响因素,pH为次要因素,最佳降解条件为温度29.74℃,pH 6.48,Na Cl浓度0.63%.在此条件下培养24 h,杀扑磷从100 mg/L降解到57.73 mg/L,降解率为42.27%,比优化前提高了6个百分点.因此菌株MS1-2能有效降解杀扑磷,优化降解条件后降解率有所提高.     

核-壳结构N(x)-TiO_2@C的制备和表面TiO_2晶相调控及可见光催化降解孔雀石绿研究

以C球为核,钛酸四丁酯和四氯化钛为钛源,不同含量尿素为氮源,通过水热法将不同N掺杂量的TiO_2包裹在C球表面.通过控制焙烧条件,调控包在C球表面的TiO_2的晶型.X射线衍射(XRD)表明,随着焙烧温度的提高,可调控TiO_2的晶型由板钛矿/锐钛矿混晶到锐钛矿/金红石混晶最后得到单一金红石相TiO_2;X射线光电子能谱(XPS)表明,N掺杂进入了TiO_2的晶格内.可见光催化降解孔雀石绿研究表明,制备过程加入1 g尿素,煅烧温度为550℃的样品N(1)-TiO_2@C-550℃,其结构为锐钛矿/金红石混晶型,可见光催化效果最好,2 h催化效率达到75%,相比P25提高了11倍.对其可见光催化降解孔雀石绿过程中活性氧物种的捕获可知,·O-2和·OH参与了反应,其中·OH起在光催化过程中占主要作用.     

萘降解菌NAP_A的分离、降解性能和分子系统学研究

该文研究降解多环芳烃类环境污染物的微生物资源、降解活性和分子系统特征.利用萘-无机盐选择性培养基分离萘降解菌,用培养技术和气相色谱法检测菌株对底物的利用和降解情况,用分子克隆技术获得菌株的16S rRNA基因并测序,用DNAMAN软件对菌株的16S rRNA基因序列进行比对和系统发育分析.从淄博张店污水处理厂的活性污泥中分离到一株能降解萘的菌株NAP_A.此菌株在30 ～35 ℃和pH 7条件下较快的降解底物萘,其中30 ℃下,10 d内可以将初始质量浓度为320 mg·L-1的萘降解90％± 4.5％.对菌株NAP_A的16S rRNA基因进行了克隆和测序(EU142847),基于菌株NAP_A和相关菌株的16S rRNA基因进行系统发育分析,结果表明菌株NAP_A位于苍白杆菌属的分枝中,其中与假中间苍白杆菌种的同源性最高,可达99％,因此推断NAP_A菌是一株假中间苍白杆菌.此前并无苍白杆菌属成员降解多环芳烃的报道.这是首例苍白杆菌属成员降解多环芳烃的报道,对今后在环境污染防治中开发利用此类细菌具有指导意义.     

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.