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181.
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
182.
Hallett Chris S. Hobday Alistair J. Tweedley James R. Thompson Peter A. McMahon Kathryn Valesini Fiona J. 《Regional Environmental Change》2018,18(5):1357-1373
Regional Environmental Change - Regions with a Mediterranean climate are generally predicted to become warmer and drier with climate change. Estuaries in these regions are influenced by a broad... 相似文献
183.
De Vela Roger Jay Wigley Kathryn Baronian Kim Gostomski Peter Alan 《Environmental science and pollution research international》2021,28(31):41881-41895
Environmental Science and Pollution Research - The biomass control potential of three metabolic uncouplers (carbonyl cyanide-p-trifluoromethoxyphenylhydrazone (FCCP), carbonyl cyanide... 相似文献
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185.
Andrea M. Dietrich Daniel L. Gallagher Kathryn A. Klawiter 《Journal of the American Water Resources Association》2001,37(2):281-293
ABSTRACT: Inputs of copper‐based crop protectants from tomato fields grown under plastic mulch agriculture (plasticulture) to an estuarine creek were investigated. Copper was measured in runoff from diverse land‐uses including conventional agriculture, plasticulture, residences, and natural areas. Water column and sediment copper concentrations were measured in plasticulture and control (nonagriculture) watersheds. Copper concentrations in plasticulture‐impacted creeks exceeded background levels episodically. High concentrations occurred during or immediately after runoff‐producing rains. Concentrations of 263 μg/L total copper and 126 μg/L dissolved copper were measured in a tidal creek affected by plasticulture; concentrations exceeded the shellfish LC50 values and the water quality criteria of 2.9 μg/L dissolved copper. Control watersheds indicated background water column levels of ≤ 4 μg/L dissolved copper with similar copper levels during periods with and without rain. The copper concentrations in tomato plasticulture field runoff itself contained up to 238 μg/L dissolved copper. Copper concentrations in runoff from other land‐uses were less than 5 μg/L dissolved copper. Creek sediment samples adjacent to a plasticulture field contained significantly higher copper concentrations than sediments taken from nonplasticulture watersheds. 相似文献
186.
Growth responses of Populus tremuloides clones to interacting elevated carbon dioxide and tropospheric ozone. 总被引:5,自引:0,他引:5
J G Isebrand E P McDonald E Kruger G Hendrey K Percy K Pregitzer J Sober D F Karnosky 《Environmental pollution (Barking, Essex : 1987)》2001,115(3):359-371
The Intergovernmental Panel of Climate Change (IPCC) has concluded that the greenhouse gases carbon dioxide (CO2) and tropospheric ozone (O3) are increasing concomitantly globally. Little is known about the effect of these interacting gases on growth, survival, and productivity of forest ecosystems. In this study we assess the effects of three successive years of exposure to combinations of elevated CO2 and O3 on growth responses in a five trembling aspen (Populus tremuloides) clonal mixture in a regenerating stand. The experiment is located in Rhinelander, Wisconsin, USA (45 degrees N 89 degrees W) and employs free air carbon dioxide and ozone enrichment (FACE) technology. The aspen stand was exposed to a factorial combination of four treatments consisting of elevated CO2 (560 ppm), elevated O3 (episodic exposure-90 microl l(-1) hour(-1)), a combination of elevated CO2 and O3, and ambient control in 30 m treatment rings with three replications. Our overall results showed that our three growth parameters including height, diameter and volume were increased by elevated CO2, decreased by elevated O3, and were not significantly different from the ambient control under elevated CO2 + O3. However, there were significant clonal differences in the responses; all five clones exhibited increased growth with elevated CO2, one clone showed an increase with elevated O3, and two clones showed an increase over the control with elevated CO2 + O3, two clones showed a decrease, and one was not significantly different from the control. Notably. there was a significant increase in current terminal shoot dieback with elevated CO2 during the 1999-2000 dormant season. Dieback was especially prominent in two of the five clones, and was attributed to those clones growing longer into the autumnal season where they were subject to frost. Our results show that elevated O3 negates expected positive growth effects of elevated CO2 in Populus tremuloides in the field, and suggest that future climate model predictions should take into account the offsetting effects of elevated O3 on CO2 enrichment when estimating future growth of trembling aspen stands. 相似文献
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188.
An increasing trend towards the use of sustainable processes has led to recycled materials being incorporated into concrete. It is generally recognised that crushed recycled construction aggregate material produces concrete of a lower compressive strength, when used as an aggregate replacement due to deleterious materials within the aggregate.It is generally accepted that in the UK, freeze/thaw attack is, after chloride-induced corrosion, the most common cause of concrete deterioration. This paper addresses the freeze/thaw durability of recycled aggregate concrete using a paired comparison test based upon weight loss and final compressive strength.Recycled aggregate concrete was found to be of at least equal durability to concrete manufactured with virgin aggregates. This was due to careful selection of the replacement aggregate and treatment prior to batching.Durability is an important material property and recycled aggregates need to be widely tested to gain confidence for use within the industry and this work shows future possibilities. 相似文献
189.
Bealey WJ McDonald AG Nemitz E Donovan R Dragosits U Duffy TR Fowler D 《Journal of environmental management》2007,85(1):44-58
Trees have been widely quoted as effective scavengers of both gaseous and particulate pollutants from the atmosphere. Recent work on the deposition of urban aerosols onto woodland allows the effect of tree planting strategies on airborne aerosol concentrations to be quantified and considered within the planning process. By identifying the potential planting locations in the local authority area, and applying them within a dispersion and deposition model, the potential magnitude of reduction in the ambient concentration of PM(10), achievable through urban tree planting, has been quantified for two UK cities. As part of the Environmental Information Systems for Planners (EISP), flow diagrams, based on planning decisions, have incorporated output from the model to make decisions on land use planning ranging from development plans and strategic planning, to development control. In this way, for any new developments that contribute to the local PM(10) level, the mitigation by planting trees can be assessed, and in some cases, reductions can be sufficient to meet air quality objectives for PM(10). 相似文献
190.
Rebecca M. Ford Kathryn J. H. Williams Ian D. Bishop John E. Hickey 《Environmental management》2009,44(6):1149-1162
The effects of viewing different types of information were investigated in people judging the social acceptability of alternative
forest harvest systems. Approximately 500 Tasmanians were shown still-simulated images of four harvest systems (a clearfell
system, two aggregated retention systems, and a selective system) and were asked to judge their acceptability. Individual
interviews were conducted with 12 of the participants. It was anticipated that people holding different beliefs about the
consequences of harvesting would have different responses to information. Cluster analysis was used to group participants
according to these beliefs. Responses to still images were compared with responses to two other types of information: information
about consequences of the harvest systems in the form of indicator symbols, and information about regeneration over time,
presented as visual animations. The effects of information differed across both harvest system and belief cluster groups of
participants. The largest effects of information occurred in people who held a mix of beliefs about consequences. Within this
group, participants who viewed the indicators rated a 30% aggregated retention system higher and selective harvesting lower,
than those who did not view the indicators. Viewing animated sequences led to slightly higher ratings of the more intensive
harvest systems and significantly lower ratings of the selective harvest system than those based on the still images. The
interview data provided examples of interviewees viewing information critically against their own values and beliefs. Only
some interviewees appeared to use it in judging social acceptability 相似文献