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141.
Concerns over the increasing popularity of wilderness recreation have resulted in attempts to determine the amount of use that different areas can tolerate without adverse affects to the resource. Early attempts to establish recreational carrying capacities focused on managers' assessments of biophysical impacts. The perceptions of wilderness visitors, however, are now considered integral to capacity decisions. This study used a stress appraisal framework to understand wilderness visitors' perceptions of on-site conditions. It was based on the premise that negative appraisals of wilderness conditions produce stress and that individual perceptions vary based on personal and situational characteristics. The purpose of the study was to assess the validity of a wilderness-hassles appraisal scale by testing hypothesized relationships between experience-use history (EUH), place attachment, and stress appraisal. Data collection occurred through a postal survey of hikers (n = 385) contacted in the High Peaks and Pemigewasset Wilderness Areas during the summer of 2004. An exploratory factor analysis indicated that stress appraisal is a multi-dimensional construct. Validity testing procedures were restricted to those dimensions that were consistent between study areas and provided partial support for the hassles scale. As hypothesized, EUH did not influence perceptions of wilderness conditions. Place attachment, on the other hand, was positively correlated with stressful appraisals of social and managerial conditions. Although Kruskall Wallis tests revealed significant differences in visitors' perceptions of managerial conditions between study sites, perceptions of social conditions did not vary significantly. Implications for management and recommendations for further refinement of the wilderness hassles construct are discussed.  相似文献   
142.
贵州岩溶地基评价及处理   总被引:1,自引:0,他引:1  
刘恒 《地球与环境》2006,34(3):87-91
以贵州为例,将山区岩溶地基分为岩石地基、红粘土地基、岩土地基三类,对各类地基评价方法及处理措施进行了详细的论述,提出了一些新的评价方法及处理措施。  相似文献   
143.
江汉平原四湖地区生态环境综合评价   总被引:6,自引:1,他引:6  
四湖地区是江汉平原的中心地带,也是国家和湖北省重要农业生产基地。这里自然资源丰富,地理条件复杂,生态问题众多,生态环境问题已经成为这一地区农业发展的制约因素。通过对四湖地区生态环境进行综合评价,遵循自然和经济的发展规律,提出了调整四湖地区的生态结构和进行环境整治的途径。  相似文献   
144.
陶涛  刘遂庆 《四川环境》2004,23(6):98-101
本文主要研究GIS在美国源水评估中的应用,介绍了地理信息系统在国内外源水评估中的重要性,详细的论述了美国源水评估地理信息系统(Water Source Appraise GIS-WSA-GIS)的开发过程,主要包括设计数据库、建造数据库、分析数据以及显示结果四个方面,从而为我国建立水源评估的GIS提供参考。  相似文献   
145.
通过对某厂房结构进行腐蚀检测鉴定,对结构损坏原因进行分析、判定,根据分析结果提出相应处理措施。  相似文献   
146.
室内空气品质评价新模型的建立与应用   总被引:2,自引:0,他引:2  
基于财务管理信用评价的方法,建立了一种全新的室内评价模型.该模型兼具现有3种主要的室内空气品质客观评价方法的优点,又集简便性和实用性于一体.并且通过实践检验,证实了该模型的正确可行性.  相似文献   
147.
Post-Project Appraisals in Adaptive Management of River Channel Restoration   总被引:5,自引:3,他引:2  
Post-project appraisals (PPAs) can evaluate river restoration schemes in relation to their compliance with design, their short-term performance attainment, and their longer-term geomorphological compatibility with the catchment hydrology and sediment transport processes. PPAs provide the basis for communicating the results of one restoration scheme to another, thereby improving future restoration designs. They also supply essential performance feedback needed for adaptive management, in which management actions are treated as experiments. PPAs allow river restoration success to be defined both in terms of the scheme attaining its performance objectives and in providing a significant learning experience. Different levels of investment in PPA, in terms of pre-project data and follow-up information, bring with them different degrees of understanding and thus different abilities to gauge both types of success. We present four case studies to illustrate how the commitment to PPA has determined the understanding achieved in each case. In Moore's Gulch (California, USA), understanding was severely constrained by the lack of pre-project data and post-implementation monitoring. Pre-project data existed for the Kitswell Brook (Hertfordshire, UK), but the monitoring consisted only of one site visit and thus the understanding achieved is related primarily to design compliance issues. The monitoring undertaken for Deep Run (Maryland, USA) and the River Idle (Nottinghamshire, UK) enabled some understanding of the short-term performance of each scheme. The transferable understanding gained from each case study is used to develop an illustrative five-fold classification of geomorphological PPAs (full, medium-term, short-term, one-shot, and remains) according to their potential as learning experiences. The learning experience is central to adaptive management but rarely articulated in the literature. Here, we gauge the potential via superimposition onto a previous schematic representation of the adaptive management process by Haney and Power (1996). Using PPAs wisely can lead to cutting-edge, complex solutions to river restoration challenges.  相似文献   
148.
宜宾江安桐梓镇土地整理区耕地土壤重金属富集因子评价   总被引:1,自引:0,他引:1  
文中采用富集因子分析方法,结合MapGIS空间分析技术,对宜宾江安桐梓镇某地区耕地土壤进行了系统的土壤重金属现状评价。评价结果一致表明,桐梓镇土地整理地区有不同程度的砷、镉、铬、铜、汞、镍、铅和锌重金属富集现象,尤其是以桐梓镇九台村为中心的周围区域富集较为明显,而铅富集程度小。此外,老王村燕子岩附近、九台村观山附近、大路村板板桥至瓦窑山一带和中心村的鸡婆山附近均有不同程度的重金属汞的富集现象。  相似文献   
149.
环境监测站激励机制探讨   总被引:1,自引:0,他引:1  
简述了建立公平合理激励机制的重要性,指出了地市级环境监测单位激励机制存在的问题.提出构建合理有效的员工激励机制,优化配置员工,实行任职激励;以岗定薪、全面完善薪酬体系,实行分配激励;完善绩效考核制度,配合薪酬制度改革;正确构建评价机制,实行评估激励;建立科学培训机制,实行培训激励;推进文化建设,实行环境激励.  相似文献   
150.
共同做好防震减灾工作,政府各职能部门要各司其职,各负其责仅靠领导重视及部门之间的密切配合还不够,必须用相应的制度做保证。还要通过不断的加强宣传,在各级领导的思想中树立起“经济建设与防震减灾工作同等重要”的观念。  相似文献   
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