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651.
Jonathan Salerno Karen Bailey Andrea E. Gaughan Forrest R. Stevens Tom Hilton Lin Cassidy Michael D. Drake Narcisa G. Pricope Joel Hartter 《Conservation biology》2020,34(4):891-902
Interactions between humans and wildlife resulting in negative impacts are among the most pressing conservation challenges globally. In regions of smallholder livestock and crop production, interactions with wildlife can compromise human well-being and motivate negative sentiment and retaliation toward wildlife, undermining conservation goals. Although impacts may be unavoidable when human and wildlife land use overlap, scant large-scale human data exist quantifying the direct costs of wildlife to livelihoods. In a landscape of global importance for wildlife conservation in southern Africa, we quantified costs for people living with wildlife through a fundamental measure of human well-being, food security, and we tested whether existing livelihood strategies buffer certain households against crop depredation by wildlife, predominantly elephants. To do this, we estimated Bayesian multilevel statistical models based on multicounty household data (n = 711) and interpreted model results in the context of spatial data from participatory land-use mapping. Reported crop depredation by wildlife was widespread. Over half of the sample households were affected and household food security was reduced significantly (odds ratio 0.37 [0.22, 0.63]). The most food insecure households relied on gathered food sources and welfare programs. In the event of crop depredation by wildlife, these 2 livelihood sources buffered or reduced harmful effects of depredation. The presence of buffering strategies suggests a targeted compensation strategy could benefit the region's most vulnerable people. Such strategies should be combined with dynamic and spatially explicit land-use planning that may reduce the frequency of negative human–wildlife impacts. Quantifying and mitigating the human costs from wildlife are necessary steps in working toward human–wildlife coexistence. 相似文献
652.
Haeldermans Tom Samyn P. Cardinaels R. Vandamme D. Vanreppelen K. Cuypers A. Schreurs S. 《Journal of Polymers and the Environment》2021,29(8):2478-2491
Journal of Polymers and the Environment - Biochar is an excellent, but less-used candidate to serve as an alternative filler in poly(3-hydroxybutyrate) (PHB)-based composites. Increasing amounts of... 相似文献
653.
Emily B. Dennis Byron J.T. Morgan Tom M. Brereton David B. Roy Richard Fox 《Conservation biology》2017,31(6):1350-1361
Citizen scientists are increasingly engaged in gathering biodiversity information, but trade‐offs are often required between public engagement goals and reliable data collection. We compared population estimates for 18 widespread butterfly species derived from the first 4 years (2011–2014) of a short‐duration citizen science project (Big Butterfly Count [BBC]) with those from long‐running, standardized monitoring data collected by experienced observers (U.K. Butterfly Monitoring Scheme [UKBMS]). BBC data are gathered during an annual 3‐week period, whereas UKBMS sampling takes place over 6 months each year. An initial comparison with UKBMS data restricted to the 3‐week BBC period revealed that species population changes were significantly correlated between the 2 sources. The short‐duration sampling season rendered BBC counts susceptible to bias caused by interannual phenological variation in the timing of species’ flight periods. The BBC counts were positively related to butterfly phenology and sampling effort. Annual estimates of species abundance and population trends predicted from models including BBC data and weather covariates as a proxy for phenology correlated significantly with those derived from UKBMS data. Overall, citizen science data obtained using a simple sampling protocol produced comparable estimates of butterfly species abundance to data collected through standardized monitoring methods. Although caution is urged in extrapolating from this U.K. study of a small number of common, conspicuous insects, we found that mass‐participation citizen science can simultaneously contribute to public engagement and biodiversity monitoring. Mass‐participation citizen science is not an adequate replacement for standardized biodiversity monitoring but may extend and complement it (e.g., through sampling different land‐use types), as well as serving to reconnect an increasingly urban human population with nature. 相似文献
654.
Cocoon-spinning larvae of the codling moth, Cydia pomonella L. (Lepidoptera: Olethreutidae) employ a pheromone that attracts or arrests conspecifics seeking pupation sites. Such intraspecific communication signals are important cues for illicit receivers such as parasitoids to exploit. We tested the hypothesis that the prepupal C. pomonella parasitoid Mastrus ridibundus Gravenhorst (Hymenoptera: Ichneumonidae) exploits the larval aggregation pheromone to locate host prepupae. In laboratory olfactometer experiments, female M. ridibundus were attracted to 3-day-old cocoons containing C. pomonella larvae or prepupae. Older cocoons containing C. pomonella pupae, or larvae and prepupae excised from cocoons, were not attractive. In gas chromatographic-electroantennographic detection (GC-EAD) analyses of bioactive Porapak Q extract of cocoon-derived airborne semiochemicals, ten compounds elicited responses from female M. ridibundus antennae. Comparative GC-mass spectrometry of authentic standards and cocoon-volatiles determined that these compounds were 3-carene, myrcene, heptanal, octanal, nonanal, decanal, (E)-2-octenal, (E)-2-nonenal, sulcatone, and geranylacetone. A synthetic 11-component blend consisting of these ten EAD-active compounds plus EAD-inactive (+)-limonene (the most abundant cocoon-derived volatile) was as effective as Porapak Q cocoon extract in attracting both female M. ridibundus and C. pomonella larvae seeking pupation sites. Only three components could be deleted from the 11-component blend without diminishing its attractiveness to M. ridibundus, which underlines the complexity of information received and processed during foraging for hosts. Mastrus ridibundus obviously eavesdrop on the pheromonal communication signals of C. pomonella larvae that reliably indicate host presence.
相似文献
Gerhard GriesEmail: |
655.
Terry V.Callaghan Lars Olof Bjrn Yuri Chernov Terry Chapin Torben R.Christensen Brian Huntley Roll A.Ims Margareta Johansson Dyanna Jolly Sven Jonasson Nadya Matveyeva Nicolai Panikov Walter Oechel Gus Shaver Sibyll Schaphoff Stephen Sitch Christoph Zckler 《Ambio-人类环境杂志》2004,33(7):445-449
在评价北极陆地生态系统影响时,人们常常强调物种和生态系统对环境变化响应的地理变化,这种变化往往与气候、生物多样性、植被带、生态系统结构和功能的南-北梯度相关联,可是,环境、生态系统的功能和结构上,以及环境史和当前气候变化的明显东-西变化显然也很重要.尽管一些地方变得温暖,但另一些地方却降温了,海洋、群岛和山脉等地理屏障的东西差异过去也对物种和植被带响应气候变化而改变分布区的能力产生了很大影响,同时,这些地理屏障为种群遗传分化和生物多样性热点区的形成提供了必要的隔离条件,这些屏障在未来气候变暖时,也将影响物种重新分布的能力.为了说明这种东西向的变化,同时也避免过分笼统或过于专业化,基于大尺度的天气和气候形成因素,北极气候影响评价项目确定了4个主要亚区.通过模拟与4个北极气候影响评价亚区有关的主要信息,导致物种分布区发生改变的地理屏障,特别是大陆的分布和海洋产生的隔离,明显会影响植被带的向北移动.对植被区向北移动的地理限制或者促进将影响将来碳的贮存和释放,以及生物圈与大气之间水和能量的交换.此外,气候变化使受威胁物种数量在各个亚区之间差别很大(白令海地区别尤其是热点),各个植被亚区重新分布的能力差异将影响每个区的生物多样性.总而言之,亚区分析表明,在整个北极地区水平上概括生态系统结构和功能的反应、物种的丧失,以及生物圈对气候系统的反馈的趋势是困难的,说明需要对北极陆地生态系统对于气候变化响应的空间变化性有深刻的认识. 相似文献
656.
FISH is a quick, inexpensive, accurate, sensitive and relatively specific method for aneuploidy detection in samples of uncultured chorionic villus cells and amniotic fluid cells. FISH allows detection of the autosomal trisomies 13, 18 and 21 and X and Y abnormalities and any other chromosome abnormality for which a specific probe is available. The detection rate of these abnormalities is high in informative samples which have a concordance of > 99.5% with cytogenetic results. A relatively high number of abnormal cases are found in uninformative samples. However, such samples should be regarded as samples to be investigated further. Clinical experience with the use of FISH for prenatal diagnosis is now beyond 10,000 cases; a number of clinical protocols and smaller trials have also been carried out, resulting in 90% of attempted analyses giving informative results with a high detection rate and extraordinarily low false-positive and false-negative rates Unsolved problems remain, such as occasional technical failures, admixtures of maternal blood and up to 20% uninformative scoring results, especially for abnormal specimens. FISH is at present used as an adjunct to classical cytogenetic analysis. However, this should not be interpreted as meaning that FISH could not be used as a methodology in its own right. If FISH were to be considered a Diagnostic test then this might be the case, due to the risk of false-negative and false-positive results and the fact that FISH does not allow a diagnosis of certain structural abnormalities. If, on the other hand, FISH is considered a screening test, which means that in all abnormal (or indeterminate) cases, classical cytogenetic analysis would follow the abnormal screening test, the accuracy which is potentially higher than for other screening methods, for example in cases of trisomy 21, justifies FISH as a prenatal screening test in its own right. 相似文献
657.
Finn Stener Jørgensen MD Jens Bang Anne-Marie Lind Britta Christensen Claes Lundsteen John Philip 《黑龙江环境通报》1992,12(4):277-283
Genetic amniocentesis performed at 7–14 weeks of gestation was studied in a series of 138 patients of whom 50 wanted termination of pregnancy (⩽ 12 weeks). The material for analysis consisted of 132 samples due to two sampling failures and four samples being handled incorrectly. Forty-eight samples (36 per cent) were taken at 7–12 weeks of gestation, mainly transvaginally (36/48:75 per cent). The success rate of culture and karyotyping increased with the duration of pregnancy, but was only satisfactory from week 11 onwards. The time until harvest was then 14–15 days. The transvaginal approach is easy to perform and was accepted by the women, but we experienced bacterial or fungal overgrowth in 17 per cent of these samples, whereas no infection occurred in the samples taken transabdominally (n = 96). We conclude that genetic amniocentesis is feasible from week 11, but further studies concerning side effects, especially focusing on the procedure-related abortion risk, should be carried out before early amniocentesis is routinely applied. 相似文献
658.
Magnetic resonance (MR) imaging was performed on two women at the 33rd and 34th pregnancy week, respectively, after ultrasonographic detection of a brain malformation. Fetal neuromuscular blockade was induced by pancuronium bromide injected into the umbilical vein under continuous ultrasound (US) guidance. MR images supported the echotomographic diagnosis of holoprosencephaly, improving the image quality and offering additional information in such cases of difficult differential fetal diagnosis. Holoprosencephaly was finally confirmed by neonatal US and autopsy (case 1), US, CT and MR (case 2). 相似文献
659.
The determination of adenosine triphosphate (ATP), adenosine diphosphate (ADP), and adenosine monophosphate (AMP) concentrations in sediments from both Puget Sound and the Washington State continental shelf (USA) has been investigated. Major losses during the extraction procedure included sediment sorption, coprecipitation, and unreactivity of the soluble adenylates presumably through irreversible binding to solubilized sediment organics. Addition of phosphoric acid and the non-ionic detergent Triton X-100 to cold sulfuric acid significantly increased the extraction efficiency and sensitivity over that of sulfuric acid alone, although both methods yielded similar results when corrected for losses. Vertical profiles of ATP, total adenylates (AT), and adenylate energy charge (EC) in sediments from both areas are presented. Profiles of AT are similar in both areas, but EC values in the shelf sediments are significantly lower, which suggests a depressed physiological condition in the shelf population relative to that in Puget Sound.Contribution No. 513 from the University of Washington's College of Fisheries, and Contribution No. 1135 from the University of Washington's Department of Oceanography 相似文献
660.
Louis V. Verchot Meine Van Noordwijk Serigne Kandji Tom Tomich Chin Ong Alain Albrecht Jens Mackensen Cynthia Bantilan K. V. Anupama Cheryl Palm 《Mitigation and Adaptation Strategies for Global Change》2007,12(5):901-918
Agriculture is the human enterprise that is most vulnerable to climate change. Tropical agriculture, particularly subsistence
agriculture is particularly vulnerable, as smallholder farmers do not have adequate resources to adapt to climate change.
While agroforestry may play a significant role in mitigating the atmospheric accumulation of greenhouse gases (GHG), it also
has a role to play in helping smallholder farmers adapt to climate change. In this paper, we examine data on the mitigation
potential of agroforestry in the humid and sub-humid tropics. We then present the scientific evidence that leads to the expectation
that agroforestry also has an important role in climate change adaptation, particularly for small holder farmers. We conclude
with priority research questions that need to be answered concerning the role of agroforestry in both mitigation and adaptation
to climate change. 相似文献