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151.
Contemporary efforts to protect biological diversity recognize the importance of sustaining traditional human livelihoods, particularly uses of the land that are compatible with intact landscapes and ecologically complete food webs. However, these efforts often confront conflicting goals. For example, conserving native predators may harm pastoralist economies because predators consume domestic livestock that sustain people. This potential conflict must be reconciled by policy, but such reconciliation requires a firm understanding of the effects of predators on the prey used by people. We used a long-term, large-scale database and Bayesian models to estimate the impacts of lynx (Lynx lynx), wolverine (Gulo gulo), and brown bear (Ursus arctos) on harvest of semi-domesticated reindeer (Rangifer tarandus) by Sami pastoralists in Sweden. The average annual harvest of reindeer averaged 25% of the population (95% credible interval = 19, 31). Annual harvest declined by 96.6 (31, 155) reindeer for each lynx family group (the surveyed segment of the lynx population) in a management unit and by 94.3 (20, 160) for each wolverine reproduction (the surveyed segment of the wolverine population). We failed to detect effects of predation by brown bear. The mechanism for effects of predation on harvest was reduced population growth rate. The rate of increase of reindeer populations declined with increasing abundance of lynx and wolverine. The density of reindeer, latitude, and weather indexed by the North Atlantic Oscillation also influenced reindeer population growth rate. We conclude that there is a biological basis for compensating the Sámi reindeer herders for predation on reindeer. 相似文献
152.
Ruth M. Thompson Jordan Hall Chris Morrison Nicole R. Palmer David L. Roberts 《Conservation biology》2021,35(6):1747-1754
Internet-based research is increasingly important for conservation science and has wide-ranging applications and contexts, including culturomics, illegal wildlife trade, and citizen science. However, online research methods pose a range of ethical and legal challenges. Online data may be protected by copyright, database rights, or contract law. Privacy rights may also restrict the use and access of data, as well as ethical requirements from institutions. Online data have real-world meaning, and the ethical treatment of individuals and communities must not be marginalized when conducting internet-based research. As ethics frameworks originally developed for biomedical applications are inadequate for these methods, we propose that research activities involving the analysis of preexisting online data be treated analogous to offline social science methods, in particular, nondeceptive covert observation. By treating internet users and their data with respect and due consideration, conservationists can uphold the public trust needed to effectively address real-world issues. 相似文献
153.
Susan C. Grana Scott K. Sakaluk Rachel M. Bowden Melissa A. Doellman Laura A. Vogel Charles F. Thompson 《Behavioral ecology and sociobiology》2012,66(9):1247-1258
The differential allocation hypothesis proposes that females mated to attractive males should invest more resources in their offspring than those mated to less-attractive males, whereas the compensation hypothesis posits that females mated to less-attractive males should invest more resources in their offspring to compensate for lower-quality young. We tested these hypotheses by manipulating attractiveness of male house wrens (Troglodytes aedon) prior to female arrival by adding extra nest sites to territories of some males while leaving control males with only a single nest site. Females laid their eggs sooner in the nests of attractive males, and attractive males were more likely to retain their territory over successive broods and were marginally more likely to obtain a mate for a second brood later in the season than were control males, thereby confirming the effect of our manipulation on male attractiveness. Experimentally enhanced attractiveness also led to increased hematocrit in males. However, there were no consistent differences in the number, size, or quality of eggs laid by females mated to attractive and control males, nor were there any differences in the size, health state, or immune function of nestlings produced from these eggs. There was also no effect of treatment on the number of nestlings surviving to fledging. Collectively, these results are inconsistent with both the differential allocation hypothesis and the compensation hypothesis. Future studies should consider the possibility that the criteria used by females in selecting a mate may vary temporally and be more flexible than generally thought. 相似文献
154.
Soil microbial and faunal community responses to bt maize and insecticide in two soils 总被引:2,自引:0,他引:2
Griffiths BS Caul S Thompson J Birch AN Scrimgeour C Cortet J Foggo A Hackett CA Krogh PH 《Journal of environmental quality》2006,35(3):734-741
The effects of maize (Zea mays L.), genetically modified to express the Cry1Ab protein (Bt), and an insecticide on soil microbial and faunal communities were assessed in a glasshouse experiment. Soil for the experiment was taken from field sites where the same maize cultivars were grown to allow comparison between results under glasshouse conditions with those from field trials. Plants were grown in contrasting sandy loam and clay loam soils, half were sprayed with a pyrethroid insecticide (deltamethrin) and soil samples taken at the five-leaf stage, flowering, and maturity. The main effect on all measured parameters was that of soil type and there were no effects of Bt trait or insecticide on plant growth. The Bt trait resulted in more soil nematodes and protozoa (amoebae), whereas insecticide application increased plant Bt concentration and altered nematode community structure. The only significant effects on soil microbial community structure, microarthropods, and larvae of a nontarget root-feeding Dipteran, were due to soil type and plant growth stage. The results indicate that, although there were statistically significant effects of the Bt trait on soil populations, they were small. The relative magnitude of the effect could best be judged by comparison with the insecticide treatment, which was representative of current best practice. The Bt trait had no greater effect than the insecticide treatment. Results from this glasshouse experiment were in broad agreement with conclusions from field experiments using the same plant material grown in the same soils. 相似文献
155.
Martin D. King Adrian R. Rennie Christian Pfrang Arwel V. Hughes Katherine C. Thompson 《Atmospheric environment (Oxford, England : 1994)》2010,44(14):1822-1825
The reactions between atmospheric oxidants and organic amphiphiles at the air–water interface of an aerosol droplet may affect the size and critical supersaturation required for cloud droplet formation. We demonstrate that no reaction occurs between gaseous nitrogen dioxide (1000 ppm in air) and a monolayer of an insoluble amphiphile, oleic acid (cis-9-octadecenoic acid), at the air–water interface which removes material from the air–water interface. We present evidence that the NO2 isomerises the cis-9-octadecenoic (oleic) acid to trans-9-octadecenoic (elaidic) acid. The study presented here is important for future and previous studies of (1) the reaction between the nitrate radical, NO3, and thin organic films as NO2 is usually present in high concentrations in these experimental systems and (2) the effect of NO2 air pollution on the unsaturated fatty acids and lipids found at the air–liquid surface of human lung lining fluid. 相似文献
156.
Paul B. Thompson Kyle Powys Whyte 《Journal of Agricultural and Environmental Ethics》2012,25(4):485-498
What is the significance of the wicked problems framework for environmental philosophy? In response to wicked problems, environmental scientists are starting to welcome the participation of social scientists, humanists, and the creative arts. We argue that the need for interdisciplinary approaches to wicked problems opens up a number of tasks that environmental philosophers have every right to undertake. The first task is for philosophers to explore new and promising ways of initiating philosophical research through conducting collaborative learning processes on environmental issues. The second task is for philosophers to recognize the value of philosophical skills in their engagements with members of other disciplines and walks of life in addressing wicked problems. The wicked problems framework should be seen as an important guide for facilitating philosophical research that is of relevance to problems like climate change and sustainable agriculture. 相似文献
157.
Potential environmental influence of amino acids on the behavior of ZnO nanoparticles 总被引:1,自引:0,他引:1
The fate of nanomaterials when they enter the environment is an issue of increasing concern and thus it is important to know how they interact with natural organic molecules since this may have a significant impact on the particles' behavior. Because of our poor knowledge in this regard, the interaction of ZnO nanoparticles with amino acids of contrasting surface charge, including Histidine (HIS), Glycine (GLY), Aspartic acid (ASP) and Glutamic acid (GLU) which occur commonly in natural habitats, such as the plant root zone, was investigated over a range of pH conditions and concentrations. The addition of the individual amino acid led to significant changes in nanoparticle colloidal zeta potential stability, particle size distribution and the extent of agglomeration. Variations in pH resulted in considerable changes in nanoparticle surface charge and hydrodynamic size. In general, the particle size distribution decreased as the amino acid concentration increased, with more acidic conditions exacerbating this effect. In addition, increased concentrations of amino acids resulted in more stable nanoparticles in aqueous suspensions. Histidine had the greatest effect on colloidal stability, followed by Glycine, Aspartic acid and finally Glutamic acid. This study illustrates how nanoparticle behavior may change in the presence of naturally occurring amino acids, an important consideration when assessing the fate of nanoparticles in the environment. Additionally, utilization of amino acids in industrial processes could reduce particle agglomeration and it could lead to a way of employing more sustainable reagents. 相似文献
158.
H.A. Clements Thomas B. McMuIlen Richard J. Thompson Gerald G. Akland 《Journal of the Air & Waste Management Association (1995)》2013,63(12):955-958
Pairs of standard NASN Hi-Vol suspended particulate samplers were operated biweekly at 25 stations (22 urban, 3 nonurban) from August to December 1969 to determine the comparability of paired samples collected under field conditions. The average of each pair of concentration values is taken as the best estimate of the true value; half the difference between each pair of sample values represents the deviation of the pair from that true value. A cumulative distribution of the individual percent deviations from the corresponding true values shows that half the measurements differ from their true value by less than ±4.5%. 90% of the measurements differ from the true value by less than ± 14%. 相似文献
159.
160.
Gerrit Kats C.R. Thompson W.C. Kuby 《Journal of the Air & Waste Management Association (1995)》2013,63(11):1089-1090
Plant injury caused by air pollutants is a well recognized effect causing economic losses totalling millions of dollars. Farm crops, forest species, and ornamentals are all affected depending upon kind of plant and degree of exposure. Benedict1 estimated the minimum annual agricultural losses in the U. S. to be $132 million in 1969-1971. Millecan2 estimated California crop losses caused by air pollutants to be at least $25 million in 1972. Recent studies by Brewer3 in which conventional greenhouses were placed in the field over cotton gave results showing yields were reduced by 10-30% in the San Joaquin valley where significant levels of photochemical smog occur. However, these estimates of losses represent little more than educated guesses because the procedures available for obtaining the information are so imprecise. 相似文献