丁噻隆在土壤中的吸附和淋溶特性

分别利用振荡平衡法和土柱淋溶法研究了丁噻隆在不同土壤中的吸附和淋溶特性及其影响因素。结果表明,丁噻隆在5种供试土壤中的吸附特性能较好地用线性模型拟合,吸附能力顺序为:东北黑土>太湖水稻土>江西红壤>南京黄棕壤>陕西潮土,吸附常数Kd为0.19~2.87 mL.g-1,吸附性能较差。丁噻隆在3种典型土壤中的淋溶试验表明其具有较强的淋溶性,淋溶速率为:江西红壤>太湖水稻土>东北黑土。影响丁噻隆吸附和淋溶的主要因素是土壤有机质含量。     

噻虫嗪在土壤中的吸附和淋溶特性

采用振荡平衡法、土壤薄层层析法和土柱淋溶法研究了噻虫嗪在砂土、粉砂壤土和砂姜黑土等3种不同理化性质土壤中的吸附和淋溶特性,探讨了农药的吸附与淋溶特性与土壤理化性质的关系以及剂型对农药淋溶特性的影响.结果表明,噻虫嗪在3种土壤中的吸附较好地符合Freundlich方程,Kd值分别为砂土1.25、粉砂壤土2.95、砂姜黑土5.10,其大小顺序与Koc值一致.黏粒含量是影响噻虫嗪在土壤中吸附性的最主要因素,有机质含量为次要因素.土壤薄层层析实验和土柱淋溶实验均表明噻虫嗪在3种土壤中的淋溶速率顺序为砂土粉砂壤土砂姜黑土,且油悬浮剂、水悬浮剂淋溶量较高,水分散粒剂次之,颗粒剂最低.噻虫嗪存在对地下水污染的潜在风险,特别是在黏粒和有机质含量低的环境下使用时,其风险应该引起足够的重视.     

青霉素钠在土壤中的吸附和淋溶特性

分别采用振荡平衡法和土柱淋溶法分析了青霉素钠在不同土壤中的吸附和淋溶特性及其影响因素。结果表明,25℃以下,3种供试土壤对青霉素钠的吸附特性能用Freundlic模型进行较好的拟合,江西红壤、太湖水稻土和东北黑土的吸附常数KF分别为30.73、39.26和64.58 m L·g-1。偏最小二乘法(PLS)分析表明土壤黏粒含量和有机质含量是影响土壤吸附青霉素钠的主要因素。供试土壤对青霉素钠的吸附自由能变化值均40 k J·mol-1,该吸附过程主要属于物理吸附,吸附能力由大到小依次为东北黑土、太湖水稻土和江西红壤。土柱淋溶试验结果显示,土壤有机质含量和黏粒含量亦是影响淋溶过程的主要因素,青霉素钠在土壤剖面中的迁移能力较弱,3种土壤淋溶性能由大到小依次为江西红壤、太湖水稻土和东北黑土。     

壬基酚在土壤中的吸附和淋溶特性

为探究壬基酚在土壤中的吸附迁移规律,分别采用振荡平衡法和柱淋溶法研究了壬基酚在南京黄棕壤、江西红壤、常熟乌栅土、太湖水稻土、东北黑土5种不同土壤中的吸附特性、移动特性,并通过比较其在不同土壤中的吸附和淋溶来分析壬基酚在土壤中吸附和淋溶性的影响因素。吸附试验表明,壬基酚在南京黄棕壤、江西红壤、常熟乌栅土、太湖水稻土、东北黑土中的吸附性均较符合Freundlich方程,Kd值分别为18.89、26.64、44.15、47.49、69.92;吸附性大小次序为:南京黄棕壤江西红壤常熟乌栅土太湖水稻土东北黑土;以有机碳含量表示的土壤吸附常数KOC在2 534.50~4 860.65之间;影响壬基酚土壤吸附性的主要因素为土壤有机质含量,土壤有机质含量增加,吸附增强;壬基酚在5种土壤中的吸附自由能为-21.02~-19.77 k J·mol~(-1),表明吸附机理主要是物理吸附。土柱试验表明,壬基酚在土壤中具有难淋溶性质,壬基酚在5种供试土壤的1~3 cm深度的淋溶滞留量最大;影响其在土壤中淋溶性的主要因素为土壤有机质含量,与吸附试验相一致。壬基酚在土壤中易吸附难淋溶,移动性弱的特点对地表土壤层具有潜在的污染风险,应该引起足够重视。     

毒草胺在环境中的降解特性研究

毒草胺是一种被广泛应用的农药,其在环境中的降解特性备受关注。文章采用室内模拟试验方法,研究了毒草胺的光解、水解及土壤降解特性。研究结果表明,毒草胺在光强为2 370l x、紫外强度为13.5μW.cm-2的人工光源氙灯条件下,光解半衰期为2.5 h,较易光解。25℃时在pH值为5.0、7.0和9.0的缓冲水溶液中,降解半衰期分别为147.5、173.3和239.0 d;50℃时半衰期分别为15.2、27.0和42.3 d,结果显示温度对其降解速率影响较大,温度增加,水解速率明显加快,水解半衰期降低约6~10倍。该药在江西红壤中降解半衰期为46.5 d,在太湖水稻土、东北黑土中降解半衰期分别为6.4和7.9 d,比较容易降解,主要为微生物降解。结果表明毒草胺在水体中具有一定的稳定性,尤其在避光条件下难以降解。但在土壤中,比较容易被微生物降解。     

可变电荷土壤对水体中磷酸根的吸附去除作用

采用一次平衡法和土柱淋溶法研究4种可变电荷土壤对磷的吸附容量,结果表明可变电荷土壤对磷有很强的吸附能力.4种土壤对磷吸附鲢的大小顺序为昆明砖红壤＞柳州红壤≈徐闻砖红壤＞鹰潭红壤,与土壤游离铁、铝氧化物的含量大小顺序一致.说明土壤铁、铝氧化物对磷酸根吸附有重要贡献.被土壤吸附的磷酸根在NO-3体系中的解吸量很小,一般不超过吸附量的10%,但在柠檬酸体系中磷酸根的解吸量量著增加,说明磷酸根主要通过非静电吸附机制被可变电荷土壤吸附.根据淋溶试验结果,昆明砖红壤、柳州红壤、徐闻砖红壤和江西红壤对磷的吸附量分别可达1 792、1 536、1 408和1 280 mg·kg-1,说明富铁可变电荷土壤可以用作水体中磷的有效吸附剂.从土柱淋溶试验获得的吸附量大于一次平衡试验所得值,说明由于磷吸附慢反应的贡献,磷的吸附量随平衡时间的增加而增加.     

典型磺胺类抗生素在稻田土中的纵向迁移

兽用抗生素的广泛使用以及畜禽粪污还田资源化利用是农田土壤抗生素污染的重要来源,而抗生素在土壤中的迁移特性对生态环境具有潜在风险.为分析典型磺胺类抗生素在土壤中的迁移特征,采用室内土柱淋溶实验研究了磺胺甲基嘧啶(SM)、磺胺二甲基嘧啶(SM2)和甲氧苄啶(TMP)在稻田土中的淋溶规律,模拟了不同淋溶时间、不同污染程度和不同降雨p H对3种磺胺类抗生素在稻田土中纵向迁移的影响.结果表明,在雨水冲刷下,3种磺胺类抗生素的淋溶迁移性为TMPSMSM2.随淋溶时间的增长和污染程度增加,磺胺类抗生素纵向迁移能力增强,进而增加其向地下水迁移的风险.3种磺胺类抗生素在酸雨作用下更容易在土壤中吸附.     

噻呋酰胺在土壤中的降解、吸附-解吸及移动特性研究

研究噻呋酰胺在土壤中的降解、吸附-解吸及移动特性,有利于评价噻呋酰胺在土壤环境中的持效性,可为其安全使用及对水资源的风险性评价提供理论依据。采用室内模拟方法研究了不同土壤类型、土壤含水量、土壤微生物和有机质含量对噻呋酰胺在土壤中降解的影响以及噻呋酰胺在土壤中的吸附、解吸及移动特性。结果表明,噻呋酰胺在3种土壤中均属于易降解,噻呋酰胺在南京黄棕壤、东北黑土、江西红壤中的降解半衰期分别为9.4、17.8、20.1 d。随着土壤湿度增加,噻呋酰胺的降解速率加快,当土壤湿度为饱和含水量80%时,微生物生长将受到抑制,降解速率减慢。土壤中微生物和有机质能加快噻呋酰胺降解,在微生物和有机质存在的条件下噻呋酰胺降解速率分别提高2.7倍和17.2倍。噻呋酰胺在3种土壤中的吸附能力为东北黑土南京黄棕壤江西红壤,吸附能力越强,解吸附能力越弱;土壤有机质含量、阳离子代换量和粘粒含量与吸附系数具有良好的相关性。噻呋酰胺在土壤中的吸附自由能在-22.70~-21.30 k J·mol-1之间,属于物理吸附。薄层层析研究表明,噻呋酰胺在江西红壤、南京黄棕壤、东北黑土中的Rf值分别为0.234、0.233、0.224,均属于不易移动。土柱淋溶试验结果表明,噻呋酰胺在3种土壤中均属于难淋溶,不易通过淋溶作用对地下水造成污染。     

噻虫胺在土壤中的吸附和淋溶特性

采用室内模拟试验方法,研究了噻虫胺在3种不同类型土壤中的吸附特性、移动特性及其影响因素.结果表明,噻虫胺在江西红壤、太湖水稻土与东北黑土中的吸附较好地符合Freundlich方程,Kd值分别为0.49、1.99和4.42,Kd值大小次序依次为:江西红壤<太湖水稻土<东北黑土.影响噻虫胺土壤吸附性的主要因素为土壤有机质.薄层层析试验显示,当溶剂展开至12.0 cm处,噻虫胺在江西红壤、太湖水稻土和东北黑土中最远移至10—12 cm、8—10 cm、4—6 cm处.土柱试验表明噻虫胺在红壤淋出液中质量分数为56.04%,太湖水稻土和东北黑土中的噻虫胺最远已移至20.0—25.0 cm和15.0—20.0 cm处.影响噻虫胺在土壤中吸附性和移动性的主要因素为土壤有机质含量.噻虫胺存在对地下水污染的潜在风险性,特别是在红壤环境下使用噻虫胺应该引起足够重视.     

毒死蜱在土壤中的残留和淋溶动态

对土壤中毒死蜱的残留和淋溶动态进行了研究.结果显示,毒死蜱在土壤中的残留降解属于一级动力学反应,在土壤中的降解半衰期为63.0 d.通过土柱模拟淋溶试验,对毒死蜱在土壤中淋溶的影响因子进行了研究.结果表明,降水量对毒死蜱的淋溶影响较大,主要表现为降水水量增大, 毒死蜱在土层中的最大淋溶深度也随之增加, 出现浓度最高峰的土层深度也越大, 两者呈正相关关系.与降水量相比,降水强度对毒死蜱的淋溶的影响相对较小.     

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.     

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     

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.     

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.     

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.