种植小麦与牧草对西北风蚀区秦王川灌区粉砂壤土风蚀的影响

为了探讨种植小麦和牧草对秦王川灌区农田风蚀的影响,以小麦(Triticum aestivum)和混播牧草披碱草(Elymus nutans)+苜蓿(Medicago sativa)及其下部土壤为研究对象,通过测定植被(或残茬)的盖度、高度和地上生物量及其下部地表的粗糙度、湿度、含水率和风蚀量来探索植被特征指标与土壤风蚀量的变化趋势以及它们之间的定量关系。结果表明:在整个风蚀季节,农田风蚀表现为秋末冬初风蚀较大、冬季较小、春季又明显增强的"U"形曲线模式,风蚀最严重季节为3—5月,而9—10月的风蚀危害也不容忽视;混播牧草的盖度、高度和地上生物量均显著大于单播小麦(P0.05);各处理地表粗糙度、湿度和土壤含水量大小顺序均为披碱草+苜蓿地小麦地裸地,而风蚀量正好相反;相关分析显示,地表风蚀量与植被特征指标中的地上生物量间的相关性最强(r=-0.841),其后依次为与植被盖度(r=-0.816)和与植被高度(r=-0.726)间的相关性;回归分析显示,植被的地上生物量每提高1 g·m~(-2),可使其下部土壤的风蚀量减少6.0 g·m~(-2);从风蚀最严重时间(3—5月)分析,小麦地与裸地的风蚀量相近,说明该区种植春小麦不利于降低土壤风蚀,而混播种植披碱草+苜蓿可显著降低农田风蚀危害,下降幅度可达57%。为了减弱秦王川灌区农田风蚀危害和改善兰州新区生态环境,当地应减少春播小麦的种植面积,大力推广种植多年生牧草(如披碱草+苜蓿)。     

祁连山北坡亚高山草地退耕还林草混合植被对土壤碳氮磷的影响

土壤有机碳、氮素和磷素是生态系统中极其重要的生态因子,土地利用变化将会引起土壤中碳、氮、磷等元素含量的变化。以祁连山北坡亚高山草地区域内三种利用方式（自由放牧天然草地、开垦20年的燕麦（Avena nuda）耕地、退耕8年的还林草混合植被）的土壤为研究对象,通过采集0~30 cm的土壤,分析土壤的理化性质得到土壤碳、氮、磷的含量,再将其转换为土壤碳、氮、磷储量,分析三种利用方式下土壤碳、氮、磷储量的差异以及影响土壤碳、氮、磷生态化学计量比的因子,旨在探讨退耕还林草工程对该地区土壤养分的影响。结果表明,3个样地的土壤碳、氮、磷储量差异显著（P〈0.05）,天然草地的有机碳、全氮储量（72.17、6.80 t·hm-2）显著高于退耕还林草地的（66.75、4.96 t·hm-2）和燕麦耕地的（36.61、3.61 t·hm-2）。这是因为,其一,比较而言天然草地受干扰小。其二,对于退耕还林草地和燕麦耕地来说,由于刈割获取地上部分,可能使得从土壤中获取的有机碳和氮素大于归还的。全磷储量则表现为燕麦耕地的（2.51 t·hm-2）显著高于天然草地的（2.17 t·hm-2）和退耕还林草地的（1.96 t·hm-2）。这是因为燕麦耕地中化肥的施用使得磷元素富集起来,所以其储量较高。与天然草地相比,耕种20年的燕麦地0-30 cm的有机碳和全氮储量分别低了35.56、3.19 t·hm-2,年平均减少速率分别为1.78、0.16 t·hm-2·a-1。与燕麦耕地相比,退耕8年的还林草地土壤有机碳和全氮储量显著升高了30.14、1.35 t·hm-2,年平均增加速率分别为3.77、0.17 t·hm-2·a-1。退耕8年的还林草地轻组有机碳比例（10.93%）显著高于天然草地（9.72%）和燕麦耕地（8.61%）。土壤含水量、容重和微生物量碳氮是影响土壤碳、氮、磷生态化学计量的重要因子。总结认为,退耕还林草混合植被对土壤碳、氮、磷库具有重要?     

刈割留茬高度对大针茅草原群落组成及物种生态位的影响

刈割是草原主要利用方式之一,对草地可持续利用具有重要的意义。为研究大针茅草原植物群落的物种组成及物种生态位对不同刈割留茬高度的响应,在内蒙古锡林郭勒盟毛登牧场大针茅典型草原,以围封不刈割(CK)为对照,设置不同刈割留茬高度(分别为留茬2、5、8 cm)处理,于2020年8月生物量高峰期进行野外取样,测定群落中所有出现物种的高度、盖度、密度及生物量,并分析了群落中物种的重要值及生态位宽度和重叠度。结果表明,草地群落中共出现6科11属13种植物,不同处理下群落优势物种均为大针茅、糙隐子草、羊草和知母。留茬8 cm处理降低了4个优势物种的重要值。其次,4个优势物种中,3种不同留茬高度处理下知母的生态位宽度最大,大针茅的生态位宽度最小。留茬8 cm和留茬2 cm处理时发生生态位重叠的物种对数均多于对照,留茬5 cm处理时发生生态位重叠的物种对数与对照最相近。随着留茬高度的增加,生态位重叠值在0.9—1之间的物种对数减少,在0—0.3之间的物种对数增加。     

荒漠化土壤养分变化的影响因素研究进展

土壤养分的变化与荒漠化植被演替有密切的关系，当草地生态系统演变为以灌丛为主的生态系统时，土壤养分的空间变异性增强，形成以灌丛为核心的“肥岛”；风蚀是造成荒漠化土壤养分迁移的重要动力，而降尘对荒漠化表层土壤养分具有富集作用；如果降尘作用大于风蚀作用，土壤养分将增加，如亚马逊盆地通过降尘每年获得的磷为1-4kg／hm^2。水蚀也是荒漠化地区土壤养分损失的主要途径，灌丛生境每年径流的损失量比草地生境的径流损失量大得多，而且草地生境发生荒漠化时其灌丛的入侵可能与土壤氮素的损失有关。在荒漠化地区，火烧可导致凋落物中43％的全氮在燃烧中逸失，火烧后土壤的侵蚀模数增加，频繁的火烧会导致灌丛草原的“肥岛”消失。对荒漠化地区自然土壤的农业开垦一般导致土壤有机质质量分数的下降，风蚀作用加强而往往导致土壤退化；但经过恢复植被和土壤改良，表层土壤养分可明显提高。目前专门针对荒漠化土壤养分循环的模型尚未报道；但荒漠化地区主要集中于干旱、半干旱地区的草原、荒漠草原地区，针对草地生态系统中土壤C、N、P、S等养分循环已经有不少模型，如EIPC模型、SPUR模型、CENTRUY模型等；它们也可以用来揭示荒漠化土壤的养分循环以及与荒漠化之间的关系；把这些模型进一步与GIS相结合，研究区域尺度上土壤养分的变化与荒漠化的关系更有现实价值。文章从多方面概括了风蚀、水蚀、火烧、植被演替、农业措施对荒漠化土壤养分的影响，以及目前荒漠化土壤养分的空间变异和荒漠化土壤养分循环的定量化研究现状。     

砒砂岩区不同留茬高度及坡向下沙棘根系分形特征

为提高内蒙古砒砂岩区沙棘(Hippophae rhamnoides)人工林根系的生长能力,对东(E)、南(S)、西(W)、北(N)不同坡向沙棘植株进行了距地表0、10、15、20 cm(即a、b、c、d)留茬高度处理,而根系分形特征是植物根系构型应对环境异质性的表型可塑性,为反映沙棘根系对不同坡向不同留茬生长环境的适应结果,基于分形理论在砒砂岩区对东、西、南、北不同坡向下留茬后的沙棘人工林的全根、主根、一级侧根及二级侧根分形特征以及根系和土壤含水率关系进行研究,以未平茬沙棘为对照(即e)。结果表明,(1)不同坡向相同留茬下沙棘根系分形维数(D)变化为E>N>W>S;土壤含水率为E>N>W>S,这与根系分形维数变化规律一致。(2)相同坡向不同留茬下沙棘根系分形维数(D)变化为c(留茬15 cm)>b(留茬10 cm)>a(留茬0 cm)>d(留茬20 cm)>e(未平茬)。(3)不同坡向不同留茬下沙棘根系各级分形维数变化为D3(二级侧根)>D2(一级侧根)>D1(主根),且D3与D呈显著正相关。(4)在相同坡向不同留茬下土壤含水率变化为:c相似文献   

留茬高度对砒砂岩区沙棘生理特征的影响

为改善内蒙古砒砂岩区沙棘(Hippophae rhamnoides)人工林的衰退现状,促进其更新复壮及可持续发展,对沙棘老龄化植株进行了距地表0、10、20 cm(即处理S0、S10和S20)留茬高度处理,以未平茬植株为对照(CK),测定各处理组沙棘的生长和生理指标的变化规律,并利用隶属函数法分析评价了不同留茬高度对沙棘生长和生理情况的综合影响。结果表明,(1)不同留茬高度和CK的净光合速率(Pn)日变化均呈现"双峰"趋势,"午休"现象明显,各处理组的Pn全天均显著高于CK且差异显著(P0.05),其中S10日均值最高,是CK的1.43倍。(2)不同留茬高度和CK的蒸腾速率(Tr)日变化趋势相同,均为单峰线,各处理组Tr值均显著高于CK,分别为CK的1.14、1.39、1.21倍,S10日均值最高。(3)不同留茬高度和CK的单叶水分利用效率(WUE)日变化趋势相似,各处理组WUE显著高于CK,分别为CK的1.24、1.35、1.27倍,S10日均值最高。(4)S10边材比导率(Ks)(1.29)显著高于CK(0.39)。S0和S10叶比导率(KL)均显著高于S20和CK(P0.05)。栓塞度表现为CKS0S10S20,差异显著(P0.05)。木材密度表现为:CKS20S0S10。(5)经分析评价表明平茬后沙棘整体生长状况优于CK,表示留茬高度对沙棘的生长发育起促进作用,总体表现为S10 (0.88)S20(0.75)S0 (0.7)CK (0.4)。留茬有利于沙棘更新复壮,留茬高度处理后沙棘表现出很强的生长能力,各生理指标均显著优于未平茬处理沙棘,且留茬高度为10 cm时最优。     

庆阳市庆城县退耕还林区土壤纤毛虫群落特征

为研究土壤纤毛虫群落对不同退耕模式生态恢复的响应及利用其群落特征来评价退还效果,采用“非淹没培养皿法”、活体观察法和培养直接计数法对甘肃省庆阳市庆城县退耕10年后的多树种混交林(APR)和单一树种经济林(A)以及两个农田对照样地(CK1和CK2)的土壤纤毛虫群落特征进行定性定量研究,同时测定各样地土壤温度、含水量、pH值、电导率、土壤孔隙度、有机质、总氮、总磷、总钾、速效氮、速效磷和速效钾含量,并分析不同退耕还模式下土壤纤毛虫群落特征参数与土壤理化因子间的相关关系。结果为:共鉴定到土壤纤毛虫127种,隶属10纲21目34科52属;退耕样地与农田对照样地土壤纤毛虫物种分布存在明显差异,退耕样地间的物种相似性减小,群落组成复杂化,纤毛虫密度、多样性指数和丰富度指数均显著高于对照(P<0.05),其中混交林物种多样性最高;土壤纤毛虫优势类群由农田样地的肾形目(Colpodida)逐渐过渡为退耕样地的散毛目(Sporadotrichida);相关性分析可知,有机质、总氮、孔隙度和pH是影响土壤纤毛虫群落组成的关键因子,不同退耕模式下土壤纤毛虫群落组成差异较大,表明土壤纤毛虫群落对该地区退耕还林生态恢复工程发生了积极的响应,因此土壤纤毛虫群落特征参数可以作为评价退还效果的重要指标。     

晋西北黄土丘陵区不同植被恢复下的土壤碳氮累积特征

探讨黄土丘陵区土壤碳氮特征及其蓄积速率对植被恢复的响应规律,不仅对于精确评估黄土高原生态恢复工程的土壤碳氮效应具有重要意义,同时也是国家积极推进碳中和战略和生态文明建设的科学基础。以晋西北黄土丘陵区—右玉县典型生态恢复区为研究对象,以相邻农田为对照,分析了不同植被类型在不同恢复年限下的土壤碳氮特征和固碳(氮)效应。结果表明:以20 a和50 a为界,植被恢复的土壤固碳(氮)效应可分为短期、中期和长期3个阶段。从短期(20 a)来看,退耕还林(草)的土壤固碳(氮)效应不明显,甚至导致了土壤表层(0—20 cm)SOC和STN含量和储量的降低,而退耕还灌的土壤碳氮增汇效应较为显著;从中期(21—50 a)来看,随着恢复年限的增加,3种植被的土壤碳氮增汇效应显著,其中草地在恢复21—35 a后,土壤固碳(氮)达到最高值,之后其SOC、STN含量和储量开始降低,而林地和灌木地的土壤碳(氮)汇效应表现显著;从长期来看(50 a),林地表层土壤碳(氮)增汇效应仍持续增强,而灌木地和草地SOC、STN含量和储量,均低于对照农田。总体来看,退耕还林在中期和长期的土壤碳氮蓄积效应相当可观,退耕还灌在短期和中期的土壤碳氮蓄积效应表现显著;对于草地,仅在退耕中期(21—35 a)表现出一定的土壤碳氮增汇效应。从表层土壤的碳氮平均蓄积速率来看,林地在退耕中期和长期,均表现出较高的平均碳氮蓄积速率,而灌木地在退耕早期(20 a),其表层土壤平均碳氮蓄积速率最快,之后,随恢复年限的增加,逐步降低,最终转变为负值(50 a);而草地仅在退耕21—35 a,土壤碳氮蓄积速率表现为正值,其余阶段均为负值。退耕还林(草)后的表层SOC含量与STN含量、C/N和土壤含水量呈明显的正相关,与土壤容重之间呈显著的负相关。土壤C/N受SOC的影响较大;土壤水分条件的改善可促进SOC和STN的积累,其对表层STN的影响程度甚至高于SOC。随着表层SOC含量的增加,会改变土壤颗粒的胶结状况,从而导致土壤容重的降低。     

甘肃省“两西”地区草地退化的成因

分析了甘肃省“两西”地区草地退化的现状，提出了两西地区草地的退化的成因：（1）草地生境的脆弱性，包括地质地貌的脆弱性，水土，热量匹配差及气候变化的影响，（2）自然外营力的驱动作用，包括干旱，风蚀，水蚀，冻融，盐渍化；（3）人为因素的影响，包括过度放牧，农垦撂荒，樵采挖药，水环境恶化 采矿及工业污染。     

甘草种植对西北风蚀区农田土壤养分及风蚀的影响

为了探讨甘草(Glycyrrhiza uralensis)植被对农田土壤风蚀和土壤养分的影响及植被覆盖措施减少土壤养分损失的机理,以甘草植被及其下部土壤为研究对象,对甘草植被的特征指标及其下部0~5 cm土层的风蚀和土壤养分含量进行分析。结果表明,随甘草生长年限的增加,甘草植被的覆盖度、高度、地上生物量和下部表土层的有机碳,速效N、P、K含量呈显著升高趋势,而表土层风蚀量及容重却呈下降趋势(P0.05);相关分析显示,甘草植被的特征指标与土壤养分间均呈显著正相关关系(P0.05),其中土壤养分与植被覆盖度间相关系数最大,其后依次为植被高度和地上生物量;回归分析显示,甘草植被的覆盖度每提高1%,可使农田表土的有机碳,速效N、P、K含量分别提高0.038 g·kg-1、0.052 mg·kg-1、0.113 mg·kg-1和0.971 mg·kg-1。风蚀区农田若采取植被覆盖措施一方面可降低表层土壤的风蚀,从而减少土壤养分的流失,另一方面可增加枯枝落叶进入土壤的几率,从而提高土壤养分的输入;通过两方面共同作用最终可使植被覆盖农田的养分流失变小。     

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.