10%精(口恶)唑禾草灵·氰氟草酯乳油在水稻上的残留动态

在湖南长沙进行田间试验,研究10%精(口恶)唑禾草灵·氰氟草酯乳油(商品名:百除)在稻田水、土壤及水稻植株中的消解与残留动态.结果表明:百除中2种有效成分精(口恶)唑禾草灵和氰氟草酯在稻田环境中的消解均符合一级动力学方程.精(口恶)唑禾草灵在稻田水、土壤及水稻植株中的半衰期分别为3.51、1.63和2.14 d,氰氟草酯的半衰期分别为3.18、1.61和2.05 d.在推荐使用剂量下,收获稻谷中精(口恶)唑禾草灵和氰氟草酯的残留量低于美国、韩国或日本残留限量标准,因此本试验条件下收获的稻谷食用是安全的.     

在线柱浓缩-液相色谱法测定水体中痕量敌草快和百草枯

采用在线柱浓缩-超快速液相色谱联用技术测定水体中痕量百草枯和敌草快.水样无需样品前处理,过滤后即可进样.采用固相萃取小柱富集待测物,以色谱梯度泵完成样品的净化后,利用阀切换技术将待测物反冲至分析柱进行分离,以二极管阵列检测器定量.方法在1.0—20.0μg.L-1范围内线性良好,百草枯和敌草快的线性相关系数分别为0.9997和0.9989.百草枯和敌草快的检出限(S/N=3)分别为0.10、0.12μg.L-1,加标回收率在96.0%—98.0%之间.用所建立的方法测定了水中痕量的百草枯与敌草快的含量,结果令人满意.     

恶唑酰草胺在稻田中的残留及消解动态

借助加速溶剂提取、凝胶渗透色谱净化和液相色谱测定方法,研究了南京和南昌两地稻田施用w为10%的恶唑酰草胺乳油后,其有效成分恶唑酰草胺在稻田中的残留及消解动态。结果表明,恶唑酰草胺在水稻植株、稻田土壤及稻田水中的消解较快,在南京和南昌两地水稻植株中的消解半衰期分别为3.5和2.2 d,在稻田土壤中的消解半衰期分别为11.7和20.2 d,在稻田水中的消解半衰期分别为1.3和2.3 d。在稻田中按照最高推荐剂量和最高推荐剂量的2倍施用恶唑酰草胺乳油,施药1次,在收获的稻秆、稻壳、糙米及稻田土壤中均未检出恶唑酰草胺。这说明恶唑酰草胺为低残留、易降解农药。     

敌草快对藻类和溞类的急性毒性及其水中含量测定

敌草快是一种非选择性、广谱的联吡啶类触杀性除草剂,主要通过干扰植物细胞膜、破坏光合作用而快速发挥效果。为探究敌草快对水生生物的毒性,测定了该化合物对羊角月芽藻和大型溞的急性毒性,并建立了高效液相色谱法测定水中敌草快含量的方法。结果表明:检测方法在1.00×10-2~3.00×10-2mg a.i.·L-1范围内的线性相关系数为0.99995,添加回收率在90.3%~109%之间,相对标准偏差(RSD)为1.10%~10.3%,保留时间在7.2 min左右。按实测浓度和理论浓度分别计算敌草快对羊角月芽藻的72 h的半数效应浓度EyC50(72 h-EyC50),分别为3.16×10-2mg a.i.·L-1和3.32×10-2mg a.i.·L-1,均为高毒;对大型溞48 h的半数效应浓度EC50(48 h-EC50)分别为1.18×10-2mg a.i.·L-1和1.33×10-2mg a.i.·L-1,均为剧毒。     

新型除草剂硝磺草酮在玉米和土壤中的残留及降解行为

利用高效液相色谱及田间试验方法,建立了硝磺草酮在土壤、玉米和植株中残留分析方法,研究了硝磺草酮在土壤和植株中的消解动态规律以及玉米中的最终残留状况.研究结果表明,在0.1—2.0 mg.kg-1质量浓度范围内,硝磺草酮的仪器响应值与质量浓度呈良好的线性关系,相关系数达到0.999以上.通过外标法定量(0.01—0.5 mg.kg-1),硝磺草酮在土壤、玉米和植株中的添加回收率分别达到75.10%—97.74%、80.08%—107.43%、86.49%—103.38%,其变异系数分别为4.01%—10.42%、3.44%—9.05%和3.06%—6.97%,在土壤、玉米和植株中硝磺草酮最低检出浓度均为0.001 mg.kg-1,该方法的灵敏度和回收率均可满足农药残留分析要求.在天津和南京开展的两年两地田间试验结果表明,硝磺草酮在土壤和植株中的残留消解动态规律符合一级动力学反应模型,硝磺草酮在土壤和植株中的残留消解半衰期分别为3.51—3.83 d和2.97—3.07 d.按推荐剂量和1.5倍推荐剂量在玉米上喷施10%硝磺草酮1次,在收获前20 d和收获时采集玉米样品,硝磺草酮最终残留量均低于方法最低检出浓度0.001 mg.kg-1.     

茚虫威对映体在土壤中的选择性降解

研究了茚虫威在4种不同类型的农田土壤中的降解动态和选择性降解行为.结果表明,添加水平在0.1—5.0 mg.kg-1的条件下,茚虫威对映体在土壤中添加回收率在(78.56±3.16)%—(108.16±5.32)%之间,最低检测限为0.01 mg.kg-1,定量限为0.05 mg.kg-1.茚虫威在土壤中的消解符合一级动力学规律,消解过程受土壤pH值、有机质含量等因素的影响.茚虫威对映体在1#—4#土壤中的降解速率存在明显的差异性,E1的半衰期分别为15.33 d、19.09 d、10.61 d、11.40 d,E2的半衰期分别为15.44 d、15.61 d、8.58 d、11.13 d,降解快慢顺序为:3#>4#>1#>2#,表明茚虫威在偏碱性的土壤中的降解速率要快于在酸性土壤中,且对映体的半衰期差异在有机质含量较高的土壤中表现得更加明显;对映体分数EF值(enantiomer fraction)表明茚虫威对映体在4种供试土壤中除了1#土壤外均存在明显的立体选择性降解.     

代森锰锌及其代谢物乙撑硫脲在马铃薯和土壤中的残留动态

采用田间试验方法研究代森锰锌及其代谢物乙撑硫脲(ETU)在马铃薯和土壤中的残留动态.气相色谱法定量分析,本方法马铃薯中代森锰锌和ETU的平均回收率分别为85.41%-95.47%和87.71%-92.19%;土壤中代森锰锌和ETU的平均回收率分别为85.61%-103.09%和91.08%-94.46%.结果表明:代森锰锌和ETU在马铃薯茎叶中消解较快,在合肥市和天津市两地其消解半衰期分别为6.41-7.89d和6.16-7.15d;在土壤中的消解半衰期分别为5.26-7.71d和9.80-10.16d.在马铃薯上使用了72%锰锌·霜脲可湿性粉剂,按照推荐剂量的2倍(3240gai·ha-1)最多施药4次,采收期距最后一次施药7d,马铃薯中代森锰锌残留量小于1.0mg·kg-1,ETU小于0.05mg·kg-1.说明该药为低残留、易消解农药.     

三唑酮在油菜-土壤生态系统中的降解与建模

为评价三唑酮可湿性粉剂在土壤-油菜生态系统中使用后的残留行为和环境安全性,进行了2 a大田试验,并比较了指数模型、GM(1,1)灰色模型、阻滞动力学模型对三唑酮降解规律的描述。结果表明:3种模型的拟合结果均达到统计学意义上显著相关;对三唑酮在土壤和油菜中降解行为模拟结果最好的分别为GM(1,1)模型和阻滞动力学模型;三唑酮在土壤中2 a的半衰期分别为3.48和4.38 d,油菜植株中分别为1.98和3.78 d,其降解受温度影响较大。     

灭线磷在稻田土壤和田水中的降解动态和残留分析

采用气相色谱法研究了10%灭线磷GR(颗粒剂,下同)中灭线磷在广东省、湖北省两地水稻田土壤和田水中的残留降解动态和最终残留量.研究结果表明灭线磷在土壤和田水中的添加回收率分别为82.85%～93.70%和85.03%～98.17%.灭线磷在稻田土壤和田水中降解动态符合一级动力学指数模型,在广东省和湖北省稻田土壤中的半衰期分别为9.73 d、10.70 d,田水中的半衰期分别为0.83 d、0.85 d.10%灭线磷GR以(1800 g(a.i.)·m~(-2)和2700 g(a.i .)·hm~(-2)两个剂量施药后,灭线磷在广东省土壤中的最终残留质量分数为0.002 3～0.0034mg·kg~(-1);2700 g(a.i.)·hm~(-2)施药后,灭线磷在湖北省土壤中的最终残留质量分数为0.001 7 mg·kg~(-1),1800 g(a.i.)·hm~(-2)施药后,在土壤中未检测出灭线磷.     

苄·丁可湿性粉剂中丁草胺在稻田土壤和田水中残留动态

采用气相色谱法研究了35%苄·丁可湿性粉剂中丁草胺在2006年和2007年湖北省、广东省2年两地水稻田土壤和水中的残留降解动态和最终残留量.研究结果表明丁草胺在土壤和田水添加回收率分别为82.78%～93.20%和90.31%～93.51%.丁草胺在稻田土壤和田水中降解动态符合一级动力学指数模型,在湖北省和广东省水稻田土壤中的半衰期分别为3.21～3.83 d、2.49～3.66 d,水稻田水中的半衰期分别为1.20～1.66 d、1.13～1.48 d.861 g(a.i.)·hm-2和高剂量1 292 g(a.i.)·hm-2两个剂量施药后丁草胺在稻田土壤中的最终残留量为0.001 0～0.002 9 mg·kg-1.     

Achieving Open Access to Conservation Science

Conservation science is a crisis discipline in which the results of scientific enquiry must be made available quickly to those implementing management. We assessed the extent to which scientific research published since the year 2000 in 20 conservation science journals is publicly available. Of the 19,207 papers published, 1,667 (8.68%) are freely downloadable from an official repository. Moreover, only 938 papers (4.88%) meet the standard definition of open access in which material can be freely reused providing attribution to the authors is given. This compares poorly with a comparable set of 20 evolutionary biology journals, where 31.93% of papers are freely downloadable and 7.49% are open access. Seventeen of the 20 conservation journals offer an open access option, but fewer than 5% of the papers are available through open access. The cost of accessing the full body of conservation science runs into tens of thousands of dollars per year for institutional subscribers, and many conservation practitioners cannot access pay‐per‐view science through their workplace. However, important initiatives such as Research4Life are making science available to organizations in developing countries. We urge authors of conservation science to pay for open access on a per‐article basis or to choose publication in open access journals, taking care to ensure the license allows reuse for any purpose providing attribution is given. Currently, it would cost $51 million to make all conservation science published since 2000 freely available by paying the open access fees currently levied to authors. Publishers of conservation journals might consider more cost effective models for open access and conservation‐oriented organizations running journals could consider a broader range of options for open access to nonmembers such as sponsorship of open access via membership fees. Obtención de Acceso Abierto a la Ciencia de la Conservación     

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 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.     

Some polyphagous Homoptera gain protection from their natural enemies by feeding on the toxic plantsSpartium junceum andErythrina corallodendrum (Leguminosae)

Summary Interactions were studied among alkaloid-containing legumes (Erythrina corallodendrum andSpartium junceum) and non-toxic plants (Citrus sinensis, Cucurbita moschata andEuphorbia tirucalli), several polyphagous homopterans,Aphis craccivora (Aphididae),Icerya purchasi, I. aegyptiaca (Margarodidae),Lepidosaphes ulmi (Diaspididae) andPlanococcus citri (Pseudococcidae), and some major natural enemies of these homopterans. Significant reductions in survival due to negative effects of alkaloid containing as compared with non-alkaloidal plants were recorded for the predatorsRodolia cardinalis andChilocorus bipustulatus, but not forCryptolaemus montrouzieri (Coleoptera: Coccinellidae),Chrysoperla carnea (Neuroptera: Chrysopidae) andSympherobius sanctus (Neuroptera: Sympherobiidae). The development time of the larvae or pupae ofR. cardinalis, C. carnea andS. sanctus was longer on the toxic plants than on the non-toxic ones. The percentage of parasitism ofA. craccivora collected from the non-alkaloidal plantsVicia palaestina andMelilotus albus was much higher than that onS. junceum. The parasitoid complexes ofA. craccivora differed between both plant groups. The nutritive value of honeydew ofI. purchasi andA. craccivora, as expressed by the life span ofEncyrtus infelix (Hymenoptera: Encyrtidae) adults, was also investigated. Life spans were significantly longer when the wasps fed on honeydew produced on non-alkaloidal plants (C. sinensis andPittosporum tobira) than on alkaloid containing plants whenI. purchasi — but notA. craccivora — was the producer. It is suggested that the chemical defense ofE. corallodendrum andS. junceum is exploited by polyphagous phytophages to reduce predation. In nature, population growth and density of four of the investigated homopterans are conspicuously high when they developed on the alkaloid containing plant species, and very low on non-alkaloid plants. The efficiency of their natural enemies may be reduced by sequestration of alkaloids (or other toxic plant compounds) or their transfer into excreted honeydew. Therefore it is assumed that a generalist phytophagous homopteran may be protected from its natural enemies, although at different rates of efficiency, if it can safely sequester the host allelochemical when it develops on toxic species within its host range.     

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.     

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.     

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.