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111.
William R. Bradley 《Journal of the Air & Waste Management Association (1995)》2013,63(2):115-120
Air pollution analyzers, because of inherent lags and response times, will not produce an exact record of pollutant concentrations. A procedure is described for determining the transfer function for an analyzer system. This transfer function is applied to the recorded output to produce a record of the actual atmospheric pollutant concentration at the inlet to the system. This procedure is applied to the carbon monoxide analyzer of the Bay Area Air Pollution Control District monitoring station in San Jose. Results show that variations in peak heights of more than 50% can exist between actual and recorded values. 相似文献
112.
Neil R. Jordan Bradley P. Smith Robert G. Appleby Lily M. van Eeden Hugh S. Webster 《Conservation biology》2020,34(4):803-810
Millennia of human conflict with wildlife have built a culture of intolerance toward wildlife among some stakeholders. We explored 2 key obstacles to improved human–wildlife coexistence: coexistence inequality (how the costs and benefits of coexisting with wildlife are unequally shared) and intolerance. The costs of coexisting with wildlife are often disproportionately borne by the so-called global south and rural communities, and the benefits often flow to the global north and urban dwellers. Attitudes and behaviors toward wildlife (tolerance versus intolerance) vary with social and cultural norms. We suggest more empathetic advocacy is needed that, for example, promotes conservation while appropriately considering those who bear the costs of conflict with wildlife. To achieve more equitable cost-sharing, we suggest limiting the costs incurred by those most affected or by sharing those costs more widely. For example, we advocate for the development of improved wildlife compensation schemes, increasing the scale of rewilding efforts, and preventing wildlife-derived revenue leaching out of the local communities bearing the costs of coexistence. 相似文献
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Micro-evolutionary processes that underpin genetic and morphological variation in highly mobile pelagic vertebrates are virtually
unknown. Previous findings preferentially invoke vicariant isolation due to large-scale physical barriers such as continental
landmasses, followed by genetic drift. However increasingly, evidence for divergence by non-random processes (e.g. selection,
plasticity) is being presented. Wedge-tailed shearwaters are wide-ranging seabirds with breeding colonies located such that
they experience a variety of environmental pressures and conditions. Previous work on this species has provided evidence of
inter-colony divergence of adult morphology and foraging modes, as well as chick developmental patterns, suggesting that reinforcement
among colonies is possible. In order to evaluate the micro-evolutionary processes driving this observed variation, our study
compared patterns of gene flow with morphological and environmental variation among four colonies of wedge-tailed shearwater
breeding within the Indo-Pacific Ocean basin. Estimates of gene flow differed according to the genetic marker used; most likely,
this is a function of different mutation rates. Nuclear introns suggest that gene flow among wedge-tailed shearwater breeding
colonies within the Indo-Pacific Ocean basin is substantial, however microsatellite markers imply that gene flow is reduced.
In general, levels of genetic divergence were relatively low and did not correlate with geographic distance, morphological
distance or environmental differences (sea-surface temperature and chlorophyll a concentration) among colonies. We suggest that genetic drift alone is unlikely to be the major source of morphological variation
seen in this species. Instead, we propose that non-random processes (selection, plasticity) underpin morphological diversity
seen in this and possibly other seabird species. 相似文献
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Despite the likely importance of post-copulatory sexual selection in simultaneous hermaphrodites, the factors influencing sperm competition in these organisms are generally unknown. We have investigated the effects of dart-shooting, mating order, and several other predictors on the proportion of offspring fathered by penultimate (Pn-1) and ultimate (Pn) sperm donors in multiply mated garden snails, Helix aspersa. While paternity ratios were biased towards the penultimate donor (mean Pn-1=0.61), the magnitude of this advantage was dependent upon which of the two donors successfully darted the recipient. Mean Pn-values increased from 0.17 when the recipient was hit by the penultimate donor to 0.39 when it was hit by the ultimate donor. Furthermore, the effect of the dart was more pronounced in the clutches of smaller recipients. From these results, and observations of live sperm in the storage organs, we propose a novel mechanism to explain the detected pattern of sperm utilization in helicid snails. Electronic supplementary material to this paper can be obtained by using the Springer LINK server located at http://dx.doi.org/10.1007/s00265-002-0519-6. 相似文献
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