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591.
João B. Teixeira Rodrigo L. Moura Morena Mills Carissa Klein Christopher J. Brown Vanessa M. Adams Hedley Grantham Matthew Watts Deborah Faria Gilberto M. Amado‐Filho Alex C. Bastos Reinaldo Lourival Hugh P. Possingham 《Conservation biology》2018,32(5):1096-1106
Although marine protected areas can simultaneously contribute to biodiversity conservation and fisheries management, the global network is biased toward particular ecosystem types because they have been established primarily in an ad hoc fashion. The optimization of trade‐offs between biodiversity benefits and socioeconomic values increases success of protected areas and minimizes enforcement costs in the long run, but it is often neglected in marine spatial planning (MSP). Although the acquisition of spatially explicit socioeconomic data is perceived as a costly or secondary step in MSP, it is critical to account for lost opportunities by people whose activities will be restricted, especially fishers. We developed an easily reproduced habitat‐based approach to estimate the spatial distribution of opportunity cost to fishers in data‐poor regions. We assumed the most accessible areas have higher economic and conservation values than less accessible areas and their designation as no‐take zones represents a loss of fishing opportunities. We estimated potential distribution of fishing resources from bathymetric ranges and benthic habitat distribution and the relative importance of the different resources for each port of total catches, revenues, and stakeholder perception. In our model, we combined different cost layers to produce a comprehensive cost layer so that we could evaluate of trade‐offs. Our approach directly supports conservation planning, can be applied generally, and is expected to facilitate stakeholder input and community acceptance of conservation. 相似文献
592.
鉴于PM2.5对人体的危害,为了提前预测PM2.5浓度值并及时通过降雨方法降低其浓度,开展了PM2.5浓度综合预测研究。通过对西安市一个空气质量监测点收集到观测数据分析与PM2.5浓度强相关的因素,随后综合考虑天气、温度、风力风向对PM2.5浓度观测值的影响,通过添加虚拟变量及因子分析提取因子的方法,将强相关因素、提取的天气、温度、风力风向因子与PM2.5浓度观测值进行回归预测,最终得到较好预测效果。 相似文献
593.
Dirac Twidwell Carissa L. Wonkka Christine H. Bielski Craig R. Allen David G. Angeler Jacob Drozda Ahjond S. Garmestani Julia Johnson Larkin A. Powell Caleb P. Roberts 《Conservation biology》2018,32(4):905-915
A modern challenge for conservation biology is to assess the consequences of policies that adhere to assumptions of stationarity (e.g., historic norms) in an era of global environmental change. Such policies may result in unexpected and surprising levels of mitigation given future climate‐change trajectories, especially as agriculture looks to protected areas to buffer against production losses during periods of environmental extremes. We assessed the potential impact of climate‐change scenarios on the rates at which grasslands enrolled in the Conservation Reserve Program (CRP) are authorized for emergency harvesting (i.e., biomass removal) for agricultural use, which can occur when precipitation for the previous 4 months is below 40% of the normal or historical mean precipitation for that 4‐month period. We developed and analyzed scenarios under the condition that policy will continue to operate under assumptions of stationarity, thereby authorizing emergency biomass harvesting solely as a function of precipitation departure from historic norms. Model projections showed the historical likelihood of authorizing emergency biomass harvesting in any given year in the northern Great Plains was 33.28% based on long‐term weather records. Emergency biomass harvesting became the norm (>50% of years) in the scenario that reflected continued increases in emissions and a decrease in growing‐season precipitation, and areas in the Great Plains with higher historical mean annual rainfall were disproportionately affected and were subject to a greater increase in emergency biomass removal. Emergency biomass harvesting decreased only in the scenario with rapid reductions in emissions. Our scenario‐impact analysis indicated that biomass from lands enrolled in the CRP would be used primarily as a buffer for agriculture in an era of climatic change unless policy guidelines are adapted or climate‐change projections significantly depart from the current consensus. 相似文献
594.
TiO2 supports doped with different amounts of Si were prepared by a sol-gel method, and 1 wt% vanadia (V2O5) loaded on Si-doped TiO2 was obtained by an impregnation method. The mole ratio of Si/Ti was 0.2, NOx conversion exceeds 94% at 300℃ and GHSV of 41,324 hr-1 , which is about 20% higher than pure V2O5/TiO2 . The catalysts were characterized by XRD, BET, TEM, FT-IR, NH3-TPD, XPS, H2-TPR, Raman and in situ DRIFTS. The results of FT-IR and XPS indicated that Si was doped into the TiO2 lattice successfully and a solid solution was obtained. V2O5 active component could be dispersed well on the support with the increasing of surface area of the catalyst, which was confirmed by Raman and XRD results. Above all, the numbers of acid sites (especially the Br nsted-acid) and oxidation properties were enhanced for Si-doped V2O5/TiO2 catalysts, which improved the deNOx catalytic activity. 相似文献
595.
为了探讨壬基酚和辛基酚对大鼠体内(5-HT)代谢的影响,为壬基酚和辛基酚暴露标志物的鉴定提供依据.选取健康雄性Sprague Dawley大鼠35只,随机分为对照组,壬基酚、辛基酚及其联合染毒低剂量组(50 mg·kg-1·d-1),壬基酚、辛基酚及其联合染毒高剂量组(150 mg·kg-1·d-1),每组5只,连续7d灌胃染毒,建立染毒动物模型.灌胃次日,利用高效液相色谱法(HPLC)检测各组大鼠尿液中5-羟色胺(5-HT)含量.结果表明,染毒组大鼠尿液中5-HT浓度均显著高于正常对照组(p<0.01);高剂量染毒组大鼠尿液中5-HT浓度均显著高于其低剂量染毒组(p<0.01);染毒第7天大鼠尿液中5-HT浓度均显著高于其染毒第3天(p<0 01)尿液中5-HT浓度随染毒剂量和染毒时间的增加而升高,有剂量-毒性效应和时间-毒性效应关系;尿液5-HT可作为评估壬基酚和辛基酚暴露的潜在生物标志物,应用于大规模人群暴露风险的监测. 相似文献
596.
<正>Pentachlorophenol(PCP)has been extensively used as a fungicide,bactericide,herbicide,molluscicide。algaecide and insecticide worldwide(Ahlborg and Thunberg,1980:Choudhury et al.,1986).Although PCP is primarily used as a preservative for wood and wood products,it has been also used in a variety of other products,including adhesives,construction materials,leather and paper.PCP is environmentally persistent with a half-life of up to 6-7 months in soil and water systems(Law 相似文献
597.
598.
水和废水中BOD_5的测定 总被引:1,自引:0,他引:1
采用YSI 5 8型溶解氧测定仪 ,将该仪器的不同校正方法与碘量法进行比对 ,测定水和废水中的BOD5。结果表明该方法简便、快捷、经济 ,适用于大批量环境样品的测定 相似文献
599.
浅析炼油厂废水中BOD与COD的关系 总被引:1,自引:0,他引:1
马慧平 《石油化工环境保护》2000,(3)
对水中 BOD5与 CODCr的相关性进行了分析 ,以通过 CODCr的值快速推算出 BOD5的值。结果表明 ,废水 BOD5与CODCr数值之间线性关系显著。在生产稳定的情况下 ,只要测定出废水的 CODCr就可通过回归方程及置信区间预算出 BOD5。预算值与实测值相比较 ,平均相对误差 <5.85% ,经统计性检验两者无显著性差异。 相似文献
600.
Treatment of turtle-breeding wastewater and domestic fecal sewage with soil cultivating system 总被引:2,自引:0,他引:2
LAO Shan-gen 《环境科学学报(英文版)》2001,13(3):342-345
IntroductionLandtreatmentsystemfortreatingmunicipalsewagehasbeenfairlydevelopedathomeandabroad ,whichisalowcostandhighefficiencysewagetreatmentmethodoncertainconditions.InthepastafewyearsartificialaquaticproductsbreedingindustryhadrapiddevelopedinChin… 相似文献