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991.
以甘肃省退耕还林(草)重点实施区为例,通过问卷调查和定量回归分析,研究农户对退耕还林(草)工程的认识和态度。总体上农民有较高的生态环境保护意识,对退耕还林(草)政策的认识基本持积极支持的态度;年龄、文化程度、家庭人口、劳动力数量、人均耕地数量、退耕还林(草)面积是影响农户环保意识和对退耕还林(草)态度的主要因素,农业和非农业农户之间存在一定差异。  相似文献   
992.
旅游环境承载力的界定和评价可为生态旅游合理开发提供依据。把旅游环境承载力纳入到资源-环境-社会经济这一复合系统中,给出了旅游环境承载力的定义,分析了其构成体系,构建了兼顾三个维度的旅游环境承载力评价指标体系,基于专家打分的结果,运用准主成份等方法进行了权重分析,并以江苏海滨为例,用模糊综合评价等方法对江苏海滨生态旅游环境承载力进行评价,得出了合理的结果,表明本评价指标体系具有较强的科学性、普适性和可操作性。  相似文献   
993.
The cumulative effect of accidental spills from oil and gas extraction in the marine environment can have significant impacts on marine wildlife. Oil and gas operators are typically required to report spill data as part of a regulatory process. We conducted a survey of the public disclosure of hydrocarbon spill data for four countries, Australia, Canada, United Kingdom and United States. There was significant variation in the spill data statistics that were publicly reported by the regulators. No country provided full disclosure of spill data or follow-up actions taken by the regulator on their website. The lack of disclosure of spill data is of concern because the scale of environmental effects is more difficult to assess, insufficient information is available to assess the accuracy of predictions made in the environmental assessment process, and without consistency of spill reporting there is no method to compare regional differences of spill rates.  相似文献   
994.
A 3D electrical resistivity imaging survey is presented in this paper. The objective was to investigate an underground wastewater system at the University of Malaya, Malaysia. Apparent resistivity data were collected along ten parallel lines using a Wenner-Schlumberger configuration; electrode cables were oriented in the x-direction with 3 m spacing. Roll-along measurements using a line spacing of 3 m were carried out covering a grid of 20 × 10 electrodes. All data sets were merged into a single data file in order to perform a 3D inversion. Two different 3D least squares algorithms, based on the robust inversion method and the smoothness-constrained technique, were used for the inversion of the apparent resistivity data. Both the horizontal and vertical extents of the anomalous zones found by inversion are displayed. The results indicate the superiority of the robust inversion method over the smoothness-constrained technique at this site. The results are in sufficient accordance with previously known information about the investigation area. The results show that 3D electrical resistivity imaging surveys, in combination with an appropriate 3D inversion method, can be highly useful for engineering and archaeological investigations as well as for environmental applications.  相似文献   
995.
[研究目的]开展水阳江流域标准孔BZK0402孔多重地层划分,探讨长江支流水阳江流域冰后期海平面变化的沉积响应以及古丹阳湖的成因和形成时代.[研究方法]以岩石地层为基础,在磁性地层和年代地层的双重约束下,对BZK0402孔进行多重地层划分.对比分析BZK0402孔和长江河谷、长江三角洲等邻区钻孔.[研究结果]BZK04...  相似文献   
996.
城轨交通引起的环境振动问题综述研究   总被引:4,自引:0,他引:4  
随着城市化进程的加快和人们生活质量的提高,城市轨道交通系统引起的沿线地面和建筑物的振动问题越来越引起人们的关注。系统地介绍了城市轨道交通的主要形式,对城市轨道交通所引起环境振动问题的国内外研究进行了综述,同时,全面分析了环境振动对人们生产生活的影响、振动产生的原因、振动预测模拟等方面的问题。对国内外有关环境振动的计算模型也系统深入地作了分析研究。  相似文献   
997.
This paper describes the development and application of an impact model for a future hypothetical sub-Plinian eruption of La Soufrière of Guadeloupe. The model was designed to assess the impact from either a single or multiple eruption scenarios, each defined in terms of a map of the intensity of three volcanic hazards; volcanogenic earthquake, tephra fallout and pyroclastic density currents. The impact from the three hazards can be assessed independently or alternatively the joint impact of the three hazards can be assessed. The outputs that are produced from the model are; the number of buildings with collapsed roofs, and the number of fatal and non-fatal casualties.  相似文献   
998.
Three microtine species are recovered from the Zhangping Caves of the Qingling Mountains, namely Microtus oeconomus, Caryomys inez and Caryomys eva. They are climate-sensitive ones with different ecological habits, therefore their distribution well corresponds to environmental variations. Statistical comparison of the distribution of fossil microtines and their counterparts nowadays displays that the climate variation of the studied area and its contiguity since the middle Pleistocene are: warm and humid at 493 ka ago, cool and humid at 259 ka ago―cold and humid at 205 ka ago―cool and humid at 28 ka ago, and warm and dry at present.  相似文献   
999.
Multi-scale support vector algorithms for hot spot detection and modelling   总被引:2,自引:2,他引:0  
The algorithmic approach to data modelling has developed rapidly these last years, in particular methods based on data mining and machine learning have been used in a growing number of applications. These methods follow a data-driven methodology, aiming at providing the best possible generalization and predictive abilities instead of concentrating on the properties of the data model. One of the most successful groups of such methods is known as Support Vector algorithms. Following the fruitful developments in applying Support Vector algorithms to spatial data, this paper introduces a new extension of the traditional support vector regression (SVR) algorithm. This extension allows for the simultaneous modelling of environmental data at several spatial scales. The joint influence of environmental processes presenting different patterns at different scales is here learned automatically from data, providing the optimum mixture of short and large-scale models. The method is adaptive to the spatial scale of the data. With this advantage, it can provide efficient means to model local anomalies that may typically arise in situations at an early phase of an environmental emergency. However, the proposed approach still requires some prior knowledge on the possible existence of such short-scale patterns. This is a possible limitation of the method for its implementation in early warning systems. The purpose of this paper is to present the multi-scale SVR model and to illustrate its use with an application to the mapping of Cs137 activity given the measurements taken in the region of Briansk following the Chernobyl accident.  相似文献   
1000.
垃圾渗滤液中溶解有机质与内分泌干扰物的吸附机理   总被引:1,自引:0,他引:1  
为了调查垃圾渗滤液中的溶解有机质(DOM) 及内分泌干扰物(EEDs) 的相互作用机理, 在实验室条件下研究了DOM对EEDs如双酚A (BPA)、雌二醇(E2)和雌酮(E1) 的吸附等温线, 并通过FTIR、1HNMR和ESR技术, 分析了DOM与EEDs的吸附机理.结果表明, 垃圾渗滤液中DOM对3种EEDs的吸附等温线符合Freundlich方程, 并且可用DOM与EEDs的吸附常数Kf预测EEDs的辛醇/水分配系数(Kow) 或有机碳分配系数(Kdoc), 其中直线回归方程为: lgKdoc=2.062Kf-5.065 (R2=0.9958, P=0.041 < 0.05).分析也表明DOM吸附EEDs的吸附过程至少存在离子键、共价键和电荷转移等多种吸附机制的协同作用.   相似文献   
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