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71.
农田防护林健康对维护绿洲生态安全、减少风沙灾害、改善局地小气候、提高农作物产量等具有重要的意义。综合运用熵值法和层次分析法确定指标权重,基于驱动力-压力-状态-影响-响应(DPSIR)模型对河西走廊农田防护林健康状况进行了评价。结果表明:(1)河西走廊农田防护林整体上处于亚健康水平,瓜州县、酒泉市肃州区、嘉峪关市和临泽县的农田防护林处于健康水平,民勤、民乐、高台和阿克塞的农田防护林处于不健康水平,其余区县农田防护林处于亚健康状态。(2)林带连续性、疏透度、修枝情况和地区经济收入是驱动区域农田防护林健康状况的关键因素。 相似文献
72.
This study integrated environmental variables together with high spectral resolution WorldView-2 imagery to detect and map Thaumastocoris peregrinus damage in Eucalypt plantation forests in KwaZulu-Natal, South Africa. The WorldView-2 bands, vegetation indices and environmental variables were entered separately into PLS regression models to predict T. peregrinus damage. The datasets were then integrated to test the collective strength in predicting T. peregrinus damage. Important variables were identified by variable importance (VIP) scores and were re-entered into a PLS regression model. The VIP model was then extrapolated to map the severity of damage and predicted T. peregrinus damage with an R2 value of 0.71 and a RMSE of 3.26% on an independent test dataset. The red edge and near-infrared bands of the WorldView-2 sensor together with the temperature dataset were identified as important variables in predicting T. peregrinus damage. The results indicate the potential of integrating WorldView-2 data and environmental variables to improve the mapping and monitoring of insect outbreaks in plantation forests. The result is critical for plantation health monitoring using a new sensor which contains important vegetation wavelengths. 相似文献
73.
Whether or not actual shifts in climate influence public perceptions of climate change remains an open question, one with important implications for societal response to climate change. We use the most comprehensive public opinion survey data on climate change available for the US to examine effects of annual and seasonal climate variation. Our results show that political orientation has the most important effect in shaping public perceptions about the timing and seriousness of climate change. Objective climatic conditions do not influence Americans’ perceptions of the timing of climate change and only have a negligible effect on perceptions about the seriousness of climate change. These results suggest that further changes in climatic conditions are unlikely to produce noticeable shifts in Americans’ climate change perceptions. 相似文献
74.
Progress made in promoting geodiversity in recent times is reviewed, concluding that it is now an established component of the Earth Sciences. However, it still lacks the status and standing of biodiversity in governmental, political and public forums. The paper assesses what can be learnt from the experience of the development and promotion of biodiversity. Based on this experience, eight suggestions for increasing the understanding and ownership of geodiversity beyond the Earth science community are provided as a basis for discussion. 相似文献
75.
Chromium pollution were investigated by sampling the abandoned chromium contaminated sites in Chongqing. Its health risk was assessed following the procedures made by USEPA. The results showed that the most seriously polluted land was found at the former production area (G4) with average Cr(VI) concentration of 3369.2 mg kg-1 on the surface soil. The assessment indicated that there was high risk of non-carcinogens for children. The assessed risk of the first layer of office area (G1) for children, chromium slag transition (G2), drainage pipeline chromium slag transition (G3) and production area (G4) for both children and adults were not acceptable (〉1.00× 106). It was strongly suggested that the accessible measures of remediation should be taken for a portion of contaminated sites before the reuse of abandoned lands. 相似文献
76.
Over the last years, geospatial web platforms, social media, and volunteered geographic information (VGI) have opened a window of opportunity for traditional Public Participatory GIS (PPGIS) to usher in a new era. Taking advantage of these technological achievements, this paper presents a new approach for a citizen-orientated framework of spatial planning that aims at integrating participatory community work into existing decision-making structures. One major cornerstone of the presented approach is the application of a social geoweb platform (the GeoCitizen platform) that combines geo-web technologies and social media in one single tool allowing citizens to collaboratively report observations, discuss ideas, solve, and monitor problems in their living environment at a local level. This paper gives an account of an ongoing participatory land-zoning process in the Capital District of Quito, Ecuador, where the GeoCitizen platform is applied in a long-term study. 相似文献
77.
作为社会化媒体的重要类型,微博已经成为继新闻网站、论坛、博客之后,网络舆论生成的主要载体,"微博问政"成为热点和趋势,政务微博也成为政府信息公开、发布权威信息、提供公共服务、加强政民互动、引导网络舆论的重要平台。随着政务微博的快速发展,一系列新问题、新挑战也逐步显现。本文结合国土资源部政务微博的现状,就如何使用政务微博为民服务,提高政务微博应用水平,促进政务微博的健康发展,提升政府公信力,提出了对策建议。 相似文献
78.
In the United States, both scholars and practitioners have repeatedly emphasized the importance of “issue framing” for garnering public support for climate change policy. However, the debate frequently overlooks the importance of counter frames. For every framing attempt by advocates of climate policy, there will be a counter frame by the opponents of climate policy. How do counter frames influence the effectiveness of issue framing as a communication strategy? To answer this question, we report results from a survey experiment on a nationally representative sample of 1000 Americans on clean energy policy, a key policy issue in the public debate on climate change in the United States. Overall, we find that different combinations of positive and negative frames have remarkably little effect on support for clean energy policy. A follow-up on-line survey experiment with a convenience sample of 2000 Americans suggests that the counter frames are responsible for undermining the effects of the original frames. 相似文献
79.
80.
【研究目的】 山东是中国矿业与农业发达省份、沂南县东部堪称其代表。掌握当地土壤重金属污染及对生态健康风险的影响对生态环境保护有重要意义。【研究方法】 系统调查分析表层土壤样品4779件,获取Hg、Cd、Cr、Ni、As、Cu、Pb、Zn等元素分布最新数据,并用地累积指数法、潜在生态危害指数法和健康风险评估模型等评价研究了生态健康风险及相关问题。【研究结果】 (1)上述重金属均量与临沂市土壤背景值大致相当,仅Hg略偏高且变异系数最大,指示当地土壤Hg受人类活动影响明显。与国家农用地土壤污染风险筛选值相比,Cu、Cr、Ni是相对主要超标元素,As、Cd、Cu、Pb超标倍数大,它们均可能会产生生态健康危害;(2)据地累积指数平均值,该区土壤总体无污染,据单样值,Hg、Cu污染最突出,其他6元素污染较轻;(3)生态风险方面,Hg、Cd是主要生态风险元素,As、Cu次之。高生态风险区为铜井镇南东部、界湖镇西北金场附近以及县城西部主城区3个片区;(4)人体健康风险方面,重金属对成人不具有非致癌风险和致癌风险,极个别地区对儿童具有非致癌风险和致癌风险,Cr、As是主要非致癌风险元素,As致癌风险最大。【结论】 沂南县东部土壤质量总体较好,铜井镇南东部、界湖镇西北金场附近以及县城西部主城区3个片区为高生态风险区,Hg、Cr、As为主要生态健康风险元素。 相似文献