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101.
研究目的:作为保障首都生态环境质量与可持续发展的关键区域,北京市西北生态涵养区的生态健康程度反映了生态文明战略部署下首都高质量发展的综合成效。本文通过构建北京市西北生态涵养区健康评价指标体系,评价该区域的生态健康程度,为生态涵养区的可持续发展提供对策建议。研究方法:PSR模型、层次分析法(AHP)。研究结果:(1)基于PSR模型构建的生态健康评价指标体系包括压力、状态和响应系统3个准则层和10个评价指标,涵盖涵养区自然生态和人类活动影响;(2)研究区4个时段的健康指数分别为0.673、0.664、0.650、0.687,生态健康等级为一般。研究结论:北京市西北涵养区生态健康状况较为稳定,在保持西北涵养区建设现有成果的基础上,需要加大生态建设的力度,进一步提高生态健康水平。  相似文献   
102.
This paper examines how corporate social responsibility (CSR) affects the level of financial distress risk (FDR). Using a sample of 1201 US-listed firms during 1991–2012, our results indicate that firms with higher CSR levels have lower FDR, suggesting that a better CSR performance makes firms more creditworthy and have better access to financing, which is rewarded with less financial defaults. This finding is robust to using alternative proxies of FDR, to controlling for potential endogeneity, and is mainly driven by the community, diversity, employee relations, and environmental dimensions of CSR. Moreover, this relationship is more prevalent in firms with strong governance mechanisms and high product market competition. It is also more exacerbated for less distressed firms and during non-crisis periods. Overall, our findings suggest that the adoption of CSR practices comes with less distress and default risks, likely leading to a more attractive corporate environment, better financial stability and more crisis-resilient economies.  相似文献   
103.
This paper focuses on the estimation of direct damages caused by three flood scenarios with different return periods in the section Făgetul de Sus – Ghimeş – Palanca Pass of Trotuș River, with the aim of highlighting the need of improved land use plans. The damage for three land use classes (residential building, infrastructure and agriculture) were estimated using the damage curves developed by the European Joint Research Centre (JRC) as well as site specific maximum damage values. The data were processed with the help of the ArcMap 10.2 software and FloodRisk tool from QGIS software. Furthermore, the flood risk was assessed using the damage – probability curves, which associates the damage with the corresponding frequency of occurrence. This method was identified and adapted to the characteristics of the study area in order to develop a methodology of flood risk assessment that is answering the question: does the lack of land use plans increase the vulnerability and the flood damage? The results showed that the greatest damages are registered for the residential building land use class for a flood probability of 0.001. In this case the damages reach up to 60% on the scale range of deterioration factor, the total damage value being 2 million euros. For the same hazard probability the total registered damage value for roads is 7500 euro, for railways is around 12,000 euro, while for agriculture is around 84,000 euro. These results highlight the need of protection measures and land use plans development and implementation. Regarding the protection measures we consider that the egalitarianism would be the concept that should be applied in the study area and also an improved cooperation between government, specialized agencies and local authorities at local level would lead to a more efficient flood risk management process. The proposed methodology can be applied for micro-scale analysis, providing quantitative results regarding the flood damage and flood risk assessment. It includes a detailed vulnerability analysis of the elements-at-risk with the aim of developing a more comprehensive approach of flood risk assessment.  相似文献   
104.
在咸阳市区采集表层土壤样品60个,包括交通主干道路两侧、城市公园、住宅小区、工矿企业周边区域4类典型功能区。采用原子吸收分光光度法测定土壤样品中Cr(铬)、Cu(铜)、Ni(镍)、Pb(铅)、Zn(锌)5种重金属的含量,运用污染指数评价法、潜在生态风险指数法对土壤重金属的污染现状及风险进行评价。结果表明:(1)咸阳市土壤中Cr、Cu、Ni、Pb、Zn 5种重金属的平均含量分别为65.11、26.91、29.81、38.26、90.94mg/kg,均超过陕西省土壤重金属元素背景值;不同城市功能区土壤重金属含量水平具有明显的差异。(2)从土壤重金属单因子污染指数来看,除重金属Pb在城市公园为中度污染外,其余元素在不同功能区及整个咸阳市均为轻度污染;从土壤重金属综合污染指数来看,不论是咸阳市还是不同功能区,其土壤环境质量等级均属于轻污染。(3)不论是综合潜在生态风险还是单个重金属元素潜在生态风险,咸阳市及不同功能区都属于低生态风险水平,且重金属Pb对综合潜在生态风险的贡献率最大(37.56%)。(4)5种重金属(Cr、Cu、Ni、Pb、Zn)对儿童和成人的非致癌风险均很小;人体(儿童和成人)暴露土壤中,Ni的综合致癌风险在可接受范围内,但明显高于下限值,而Cr的综合致癌风险则是显著的;人体(儿童和成人)暴露土壤重金属而产生的非致癌风险和致癌风险的主要途径是直接摄入和皮肤接触。  相似文献   
105.
The purpose of this paper was to investigate the interactions between perceived benefits and risks of outsourcing and outsourcing adoption from the hoteliers’ perspective. Data were collected from 123 hotels in Egypt using a list of 32 hotel activities. Results revealed that managers’ perceived benefits of outsourcing had a direct positive effect on the current level of outsourcing, while indirect effects on the desired level of outsourcing. Interestingly, results confirmed the mediating role of current outsourcing between managers’ perceived benefits and the desired outsourcing. However, the perceived risks of outsourcing had a nonsignificant moderating effect. The findings provide implications for both theory and practice.  相似文献   
106.
股权众筹融资模式是一种典型的新业态互联网金融模式。处于股权众筹融资产业链核心的股权众筹平台近年来快速发展,并伴随着道德风险、法律风险、投资风险和管理风险4大风险类别。基于回应性监管原理,对金融新业态的回应性监管,在行业发展初期应该采取超罚策略与鼓励强化自我监管策略同时使用的方法,使全行业树立底线思维,防止大规模道德风险的产生。同时应通过监管逐步升级、引入和加强第三方监管、倡导强化自我监管、加强与行业内发展较快企业的沟通等多种方式建立多方共治的"大监管"格局,防止严重的法律风险、投资风险发生,并改善管理风险。  相似文献   
107.
以我国深圳证券交易所主板2011—2016年A股上市公司为样本,通过计算可操纵性应计利润衡量审计质量,使用上市公司违规数据衡量经营和交易违规风险与虚假披露风险,考察网络媒体关注的风险抑制作用。研究发现:网络媒体关注度与审计质量具有风险抑制效应,且网络媒体关注对风险的抑制作用更显著;进一步地,网络媒体关注可通过提高审计质量来抑制企业违规风险,审计质量在网络媒体关注与风险抑制之间发挥部分中介作用。  相似文献   
108.
The purpose of this study was to develop and evaluate a Chinese-Mandarin version of the revised new ecological paradigm (NEP-R) scale. In a sample of 515 Mandarin-speaking Chinese nationals, we first assessed the factor structure and internal consistency of the NEP-R and assessed its validity by examining associations with global warming risk perceptions and mitigation behavior. Respondents completed the NEP-R scale, together with measures of risk perception and mitigation behavior. Exploratory and confirmatory factor analyses indicated that a two-factor solution, reflecting ecocentric and anthropocentric worldviews, best fit the data. Multi-group path analysis revealed that respondents with stronger ecocentric and weaker anthropocentric worldviews perceived more risks associated with global warming. In turn, respondents who perceived more risks reported engaging in more global warming mitigation behaviors. But importantly, the path between risk perceptions and behavior was significantly stronger for highly educated respondents than for less educated respondents, suggesting that education may represent an important strategy for bridging the gap between perceived risks about global warming and action.  相似文献   
109.
自然生态空间用途管制分区划定研究——以平潭岛为例   总被引:1,自引:0,他引:1  
研究目的:在明确自然生态空间内涵和分类的基础上,探讨自然生态空间用途管制分区划定的逻辑框架和技术方法,提出自然生态空间分类、分级管制规则。研究方法:文献综述与GIS空间分析。研究结果:根据不同自然生态系统类型及其空间分布特征将自然生态空间类型划分为森林生态空间、草地生态空间、湿地生态空间和荒地生态空间;基于景观功能识别并按不同管控等级将自然生态空间管制类型区划分为红线区、橙线区和黄线区;同时,依据不同地块主要功能进一步确定自然生态空间用途管制分级,划定用途管制分区结果。研究结论:基于"区域主体功能—景观主导功能—地块主要功能"的自然生态空间管制分区划定逻辑框架,可为构建以功能分类、用途分区、管控分级为导向的自然生态空间用途管制体系提供理论依据和实践借鉴。  相似文献   
110.
Drought is a complex natural hazard with social and environmental implications. Satellite information is increasingly used to support decision-makers in preventing or coping with the negative impacts of drought. The integration of local and scientific knowledge to support drought monitoring is still far from being the main procedure in the development of drought monitoring and early warning systems. This study aimed at assessing the degree of convergence between satellite information on the effect of droughts on rangeland vegetation, from time series analysis, and farmers’ perception of drought in North-West Patagonia, Argentina. We characterised the scientific evidence of drought in terms of duration, spatial distribution, most severe years and recovery for the period 2000–2018 by identifying inter-annual NDVI changes. Farmers’ perceptions and experiences of drought were studied with open-ending interviews, with respect to occurrence, duration and recovery for that period. Satellite information matched farmers’ perception of drought at a regional scale, emphasising the value of remote sensing tools in supporting regional policy decision-making. However, farmers’ perceptions and recall of past drought impacts were more diverse than satellite information at a local level, highlighting the need for knowledge integration at finer scales.  相似文献   
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