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261.
Using spatial patterns in illegal wildlife uses to reveal connections between subsistence hunting and trade
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Ada Sánchez‐Mercado Marianne Asmüssen Kathryn M. Rodríguez‐Clark Jon Paul Rodríguez Wlodzimierz Jedrzejewski 《Conservation biology》2016,30(6):1222-1232
Although most often considered independently, subsistence hunting, domestic trade, and international trade as components of illegal wildlife use (IWU) may be spatially correlated. Understanding how and where subsistence and commercial uses may co‐occur has important implications for the design and implementation of effective conservation actions. We analyzed patterns in the joint geographical distribution of illegal commercial and subsistence use of multiple wildlife species in Venezuela and evaluated whether available data were sufficient to provide accurate estimates of the magnitude, scope, and detectability of IWU. We compiled records of illegal subsistence hunting and trade from several sources and fitted a random‐forest classification model to predict the spatial distribution of IWUs. From 1969 to 2014, 404 species and 8,340,921 specimens were involved in IWU, for a mean extraction rate of 185,354 individuals/year. Birds were the most speciose group involved (248 spp.), but reptiles had the highest extraction rates (126,414 individuals/year vs. 3,133 individuals/year for birds). Eighty‐eight percent of international trade records spatially overlapped with domestic trade, especially in the north and along the coast but also in western inland areas. The distribution of domestic trade was broadly distributed along roads, suggesting that domestic trade does not depend on large markets in cities. Seventeen percent of domestic trade records overlapped with subsistence hunting, but the spatial distribution of this overlap covered a much larger area than between commercial uses. Domestic trade seems to respond to demand from rural more than urban communities. Our approach will be useful for understanding how IWU works at national scales in other parts of the world. 相似文献
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Steven R. Abt Christopher I. Thornton Bryan A. Scholl Theodore R. Bender 《Journal of the American Water Resources Association》2013,49(4):923-937
Rock riprap is one of the most widely used erosion control methods for protecting embankments, levees, spillways, and instream structures subjected to overtopping flow conditions. At least 21 stone‐sizing relationships exist to determine the median stone size of a protective riprap layer based on the results of 96 overtopping, laboratory experiments. Test parameters include median stone size, slope, unit discharge, coefficient of uniformity, and riprap layer thickness. A regression analysis was performed relating the observed median stone size to the predicted median stone size to each of the 21 relationships, yielding a coefficient of determination (R2) and percent error for the full spectrum of data. Zonal (partial spectrum of rock sizes) and complexity analyses were also conducted for each relationship. It was resolved that the Khan and Ahmad, and Chang relationships best aligned with the composite dataset. The predictive expressions by Olivier, Hartung and Scheuerlein, Knauss, Maynord, Abt and Johnson, and Siebel yield a noteworthy second tier of stone‐sizing relationships for overtopping conditions. 相似文献
264.
Aleksandar K. Božic Robin C. Anderson Steven C. Ricke Philip G. Crandall Corliss A. O’Bryan 《Journal of environmental science and health. Part. B》2013,48(4):269-274
The gastrointestinal tract of bovines often contains bacteria that contribute to disorders of the rumen, and may also contain foodborne or opportunistic human pathogens as well as bacteria capable of causing mastitis in cows. Thus there is a need to develop broad-spectrum therapies that are effective while not leading to unacceptably long antibiotic withdrawal times. The effects of the CH4-inhibitors nitroethane (2 mg/mL), 2-nitro-1-propanol (2 mg/mL), lauric acid (5 mg/mL), the commercial product Lauricidin® (5 mg/mL), and a finely ground product of the Hawaiian marine algae, Chaetoceros (10 mg/mL), were compared in pure cultures of Streptococcus agalactia, Enterococcus faecium, Streptococcus bovis, and in a mixed lactic acid rumen bacterial culture. Lauricidin® and lauric acid exhibited the most bactericidal acidity against all bacteria. These results suggest potential animal health benefits from supplementing cattle diets with lauric acid or Lauricidin® to improve the health of the rumen and help prevent shedding of human pathogens. 相似文献
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Zhongbo Yu Richard A. White Yingjie Guo Jon Voortman Philip J. Kolb Douglas A. Miller Art Miller 《Journal of the American Water Resources Association》2001,37(4):957-971
ABSTRACT: With the increasing availability of digital and remotely sensed data such as land use, soil texture, and digital elevation models (DEMs), geographic information systems (GIS) have become an indispensable tool in preprocessing data sets for watershed hydrologic modeling and post processing simulation results. However, model inputs and outputs must be transferred between the model and the GIS. These transfers can be greatly simplified by incorporating the model itself into the GIS environment. To this end, a simple hydrologic model, which incorporates the curve number method of rainfall‐runoff partitioning, the ground‐water base‐flow routine, and the Muskingum flow routing procedure, was implemented on the GIS. The model interfaces directly with stream network, flow direction, and watershed boundary data generated using standard GIS terrain analysis tools; and while the model is running, various data layers may be viewed at each time step using the full display capabilities. The terrain analysis tools were first used to delineate the drainage basins and stream networks for the Susquehanna River. Then the model was used to simulate the hydrologic response of the Upper West Branch of the Susquehanna to two different storms. The simulated streamflow hydrographs compare well with the observed hydrographs at the basin outlet. 相似文献
267.
Intra-abdominal masses and cystic lesions are not commonly identified during the routine 20-week anomaly scan but are not infrequently seen as incidental findings during a third trimester scan assessing fetal growth and well being. This review looks at the potential differential diagnosis of masses and cysts seen prenatally and aims to define a method of assessment that will help limit the differential diagnosis before delivery. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
268.
Jon McVey Erlandson 《Journal of Coastal Conservation》2012,16(2):137-142
The human history of coastal regions around the world has been under assault for decades, from forces that include dam building,
coastal modifications, the destruction of wetlands, marine erosion, population growth and rampant development, looting, and
other processes. Global warming will exacerbate the destruction of cultural resources in coastal zones through accelerated
sea level rise, intensified storm cycles, and related coastal erosion. Although average global sea levels have been rising
for ∼20,000 years, they slowed dramatically about 7,000 years ago. Rates of sea level rise now appear to be increasing rapidly
due to growing anthropogenic emissions of carbon dioxide and other greenhouse gases. Global warming and rising seas, especially
when combined with population growth and the implementation of measures designed to protect endangered coastal properties,
threaten the deep maritime history of human migrations, settlement, and adaptations in coastal areas around the world. Ranging
in age from the mid-Pleistocene to recent historic times, coastal archaeological sites contain invaluable data on ancient
coastal societies, fisheries, and ecosystems. Archaeologists, historians, and other cultural resource managers must do more
to anticipate, evaluate, and mitigate the effects of global warming, sea level rise, and coastal erosion on the long history
of human maritime cultures. 相似文献
269.
Simone L. Stevenson Skipton N. C. Woolley Jon Barnett Piers Dunstan 《Conservation biology》2020,34(3):622-631
Marine protected areas (MPAs) are the preferred tool for preventing marine biodiversity loss, as reflected in international protected area targets. Although the area covered by MPAs is expanding, there is a concern that opposition from resource users is driving them into already low-use locations, whereas high-pressure areas remain unprotected, which has serious implications for biodiversity conservation. We tested the spatial relationships between different human-induced pressures on marine biodiversity and global MPAs. We used global, modeled pressure data and the World Database on Protected Areas to calculate the levels of 15 different human-induced pressures inside and outside the world's MPAs. We fitted binomial generalized linear models to the data to determine whether each pressure had a positive or negative effect on the likelihood of an area being protected and whether this effect changed with different categories of protection. Pelagic and artisanal fishing, shipping, and introductions of invasive species by ships had a negative relationship with protection, and this relationship persisted under even the least restrictive categories of protection (e.g., protected areas classified as category VI under the International Union for Conservation of Nature, a category that permits sustainable use). In contrast, pressures from dispersed, diffusive sources (e.g., pollution and ocean acidification) had positive relationships with protection. Our results showed that MPAs are systematically established in areas where there is low political opposition, limiting the capacity of existing MPAs to manage key drivers of biodiversity loss. We suggest that conservation efforts focus on biodiversity outcomes and effective reduction of pressures rather than prescribing area-based targets, and that alternative approaches to conservation are needed in areas where protection is not feasible. 相似文献
270.
Following years of progress in designing and executing cleanups of contaminants at waste sites, the U.S. Air Force, state regulatory groups, and others are crafting methods to evaluate broader considerations of risk in remedial decisions. Integrating worker and climate risks into remediation efforts may confer significant benefits, but challenges exist to identifying, assessing, and accounting for them in the remedial process. For sites where future risk posed by contamination far exceeds the risk posed to workers who may be exposed to the contaminants during the remedial process, limiting the range of decision inputs to those presented by the site conditions made sense and provided a net benefit to human health and the environment. There are other sites, however, where future risk posed by the in situ contamination are at levels comparable to the real risks posed to workers, ecology, and even emerging concerns about climate change. For these sites, a net risk reduction cannot be assumed to be a result of remedial action, challenging the remedial community to develop new approaches to ensure positive results. © 2009 Wiley Periodicals, Inc. 相似文献