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41.
42.
Adam C. Landon Maarten H. Jacobs Craig A. Miller Jerry J. Vaske Brent D. Williams 《社会与自然资源》2020,33(5):574-593
AbstractIncreasing wolf populations are a concern for wildlife managers in the Midwestern U.S. Understanding the psychological mechanisms that contribute to public perceptions of risk will enable development of strategies that seek to mitigate these risks, and suggest where outreach efforts may facilitate acceptance of wolves. We examined the psychological factors that influence Illinois residents’ perceived risks from wolves. We hypothesized that individuals’ perceived risks from wolves were a function of their attitudes toward wolves, negative affect toward wolves, and basic beliefs about wildlife. Data were obtained from a survey of the Illinois public (n?=?784). Negative affect and attitudes toward wolves were direct predictors of perceived risks. Basic beliefs predicted attitudes and negative affect toward wolves. Negative affect predicted attitudes. Basic beliefs had direct and indirect effects on perceived risks. 相似文献
43.
根据长山群岛 1965-2016 年渔业统计资料,分析长山群岛海域主要捕捞渔获物产量、平均营养级 (Mean trophic level, MTL)、渔业均衡指数 (Fishing in balance index,FiB) 年际变化,探讨其海洋渔业资源利用状况,并利用小波分析方法研究52年来渔获物 MTL 周期变化特征。研究表明: (1) 长山群岛捕捞产量、MTL 和 FiB 指数呈阶段性变化; (2) 长山群岛渔业资源开发经历初期开发、扩张捕捞、过度捕捞、资源破坏等四个阶段,渔业资源环境正在逐渐恶化;(3) 受人类捕捞活动影响,MTL 在 15~19 年和 24~34 年两种时间尺度下呈周期波动,30 年为第一主周期,17 年为第二主周期。长山群岛渔业资源破坏日益严重,未来几年平均营养级将呈下降趋势。为防止渔业资源进一步衰退,应加强捕捞活动管理力度,落实海洋渔业资源保护制度;完善预警机制,构建海洋渔业资源监测系统;同时应积极调整长山群岛渔业产业结构,提高资源产出效率. 相似文献
44.
ABSTRACTCharacterizing, understanding and better estimating uncertainties are key concerns for drawing robust conclusions when analyzing changing socio-hydrological systems. Here we suggest developing a perceptual model of uncertainty that is complementary to the perceptual model of the socio-hydrological system and we provide an example application to flood risk change analysis. Such a perceptual model aims to make all relevant uncertainty sources – and different perceptions thereof – explicit in a structured way. It is a first step to assessing uncertainty in system outcomes that can help to prioritize research efforts and to structure dialogue and communication about uncertainty in interdisciplinary work. 相似文献
45.
选取贵州省纳雍县为易地扶贫迁入地研究对象,构建了评价指标体系,对迁入地资源环境压力进行了评价;同时应用层次分析法确定指标权重,计算资源环境压力,并将结果划分为相对高、中、低压力区3个等级。分析结果表明,纳雍县整体资源较为贫乏,生态环境较为脆弱,人均资源量较少,造成资源环境整体压力较大;由贫困发生率与资源环境评价值作相关分析,资源环境压力与贫困发生率呈弱负相关性。 相似文献
46.
Jamaledin Baniamerian Shuang Liu Xiangyun Hu Maurizio Fedi Mahak Singh Chauhan Mahmoud Ahmed Abbas 《Geophysical Prospecting》2020,68(7):2320-2342
Inversion of magnetic data is complicated by the presence of remanent magnetization, and it provides limited information about the magnetic source because of the insufficiency of data and constraint information. We propose a Fourier domain transformation allowing the separation of magnetic anomalies into the components caused by induced and remanent magnetizations. The approach is based on the hypothesis that each isolated source is homogeneous with a uniform and specific Koenigsberger ratio. The distributions of susceptibility and remanent magnetization are subsequently recovered from the separated anomalies. Anomaly components, susceptibility distribution and distribution of the remanent and total magnetization vectors (direction and intensity) can be achieved through the processing of the anomaly components. The proposed method therefore provides a procedure to test the hypotheses about target source and magnetic field, by verifying these models based on available information or a priori information from geology. We test our methods using synthetic and real data acquired over the Zhangfushan iron-ore deposit and the Yeshan polymetallic deposit in eastern China. All the tests yield favourable results and the obtained models are helpful for the geological interpretation. 相似文献
47.
基于Sentinel-2的潮间红树林提取方法 总被引:1,自引:0,他引:1
位于潮间带的红树林可能在高潮时被海水淹没的特点,使得传统的植被提取方法在红树林信息提取方面存在局限性。本文在对比分析了出露的红树林、高潮水位淹没的红树林、海水水体的光谱特征后,提出了一种利用归一化潮间红树林指数(NIMI)提取潮间带红树林的方法。该指数是由植被强吸收的红波段,强反射的两个红边波段和近红外波段组成的归一化表达式。利用该指数对福建省龙海九龙江口湿地的红树林进行了分类提取,提取结果与高分二号影像目视验证和现场调查结果进行了对照。结果显示,该方法提取红树林的用户精度达到93.98%,并显著优于利用归一化水体指数(NDWI)、归一化植被指数(NDVI)及随机森林的结果。 相似文献
48.
The disruption of a transportation network can have a high social and economic impact on the welfare of a society, as it can significantly affect the daily routines of a community. Although many studies have focused on the estimation of physical risk in the components that compose these networks, only a limited number have analyzed their interconnections and impact in the traffic flow. The present study analyzes how earthquake damage can disrupt the road network in an urban environment, and how this will influence the ability of the population to travel. Traffic due to daily commutes is modeled for different layouts of the network, corresponding to possible disruptions caused by earthquake damage. The duration and length of each trip were calculated both for the undamaged network conditions and for the disrupted network. The increase in the median duration and length of each trip allows estimating the economic loss for each event due to drivers' delay. By combining the probability of a specific road being blocked with its number of users, the average number of affected vehicles was estimated, and the most critical segments identified. The methodology was applied to a case study concerning the road network of the area around the Italian city of Messina in Sicily. The results were calculated for both a repetition of the well-known historical event of 1908 and a set of simulated earthquakes consistent with the national probabilistic seismic hazard model of Italy. 相似文献
49.
全球气候变化下南海诸岛保护优先区识别分析 总被引:3,自引:1,他引:2
全球变化下,珊瑚礁保护区是保护生物多样性、增强珊瑚礁对气候变暖抵抗力的有效方式,而维持珊瑚礁弹性是其核心内容。针对珊瑚礁最具有威胁性的热压力因子,基于南海1982—2009年卫星观测海表面温度(SST)数据和CMIP5加拿大地球系统模式CanESM2模型预估的2006—2100年南海SST数据构建热压力强度模型,从维持珊瑚礁弹性的角度识别IPCC RCP 4.5和RCP 8.5情景下南海诸岛保护优先区。结果表明:RCP 4.5和RCP 8.5情景下13%左右的南海诸岛珊瑚礁识别为保护优先区。根据热压力强度与珊瑚抵抗力及避难所关系,西沙群岛七连屿和晋卿岛近年观测与未来预估的热压力强度均比较低,在保障其服务功能的基础上建议实施完全保护;东沙群岛东沙环礁和中沙环礁排洪滩近年观测急性热压力强度较高但未来预估热压力强度较低,建议实施50%禁止利用保护;中沙群岛黄岩岛近年观测和未来预估的急性热压力强度均比较低,建议实施50%多用途保护。南沙群岛有14%左右的珊瑚礁识别为保护优先区,根据其热压力强度可实施30%~100%禁止利用保护或30%~50%多用途保护。RCP 4.5和RCP 8.5情景下的南海诸岛保护优先区及保护对策,可为维持珊瑚礁生态弹性及应对全球气候变化提供重要的参考价值。 相似文献
50.
近年来,济南岩溶水有机污染越来越突出,为了探究济南岩溶水有机污染对居民健康造成的影响,保障饮用水安全,该文在系统分析研究区水文地质条件的基础上,采用USEPA推荐的健康风险评价模型,根据实际采样测试数据,分析评价了济南东部3处岩溶水井点的有机污染对其范围内暴露人群造成的健康风险。结果表明:检出的主要有机污染物为三氯甲烷、四氯化碳、三氯乙烯、四氯乙烯。3个水井的有机污染非致癌风险未超过限值1,在可接受的范围内,四氯化碳的非致癌风险所占比例最大,为89.85%; 3个采样点有机污染致癌风险,超出了其可接受水平的最小限制10-6,但均未超出可接受的致癌风险的最大限制10-4,风险指数均在10-6~5.0×10-5之间,应该引起关注,产生致癌风险的主要污染物为三氯乙烯。有机污染非致癌风险和致癌风险的主要暴露途径为呼吸吸入,其次是饮水吸收,皮肤接触暴露途径风险值最小。 相似文献