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141.
This study presents a method for assessing conservation opportunity on private land based on landholders' socio-economic, behavioral, and farm characteristics. These characteristics include age, gender, education, level of off-farm income, farm size, proportion of remnant native vegetation on-farm, and ecological value of native vegetation on-farm. A sample of landholders who own greater than 2 ha of land in the South Australian Murray-Darling Basin region were sent a mail-based survey about their values and preferences for environmental management (N = 659, 52% response). Cross-tabulations and ANOVA statistical analysis techniques were used to compare the socio-economic attributes across three landholder classes: disengaged, moderately engaged, and highly engaged in native vegetation planting. Results indicate that highly engaged landholders were more likely to be female, formally educated, hobby farmers who managed small parcels of land and have high off-farm incomes, whereas disengaged landholders held significantly stronger farming connections (more farming experience, family have lived on the farm for more generations). Spatial analysis revealed area-specific differences in conservation opportunity and conservation priority. In some areas, properties of high ecological value were managed by highly engaged landholders, but nearby properties of high value were managed by moderately engaged or disengaged landholders. Environmental managers therefore cannot assume areas of high conservation priority will be areas of high conservation opportunity. At the regional scale, the potential for revegetation seems most promising within the moderately engaged landholder group considering the vast amount of land managed by this group in areas of high ecological value, particularly within the less represented Mallee and Coorong and Rangelands sub-regions. We suggest that incentive schemes which purchase conservation need to be targeted at disengaged landholders; mentoring schemes led by commercial farmers highly engaged in native vegetation planting should be directed at moderately engaged landholders, and; awards programs which acknowledge conservation successes should be targeted at highly engaged landholders.  相似文献   
142.
An empirical model of landowners' conservation incentive program choice is developed in which information about landowners' socio-economic and property characteristics and their attitudes, is combined with incentive program attributes. In a Choice survey landowners were presented with the choice of two incentive programs modelled as 'bundles of attributes' mimicking a voluntary choice scenario. Landowner behaviour and decision and the type of conditions and regulations they preferred were analyzed. Based on choice survey data, landowner heterogeneity was accounted for using a latent class approach to estimate the preference parameters. Three latent classes of landowners with different attitudes to the role and outcome of establishing conservation reserves on private land were identified: multi-objective owners; environment owners; and production owners. Only a small proportion of landowners, mostly environment owners, would voluntarily join a program. Although compensation funding contributed to voluntary program choice for multi-objective owners and environment owners, welfare losses were around 4000 AUD per hectare, which is less than the average agricultural land value in Tasmania. Landowners for whom compensation funding contributed to voluntary program choice were also most likely to set aside land for conservation without payment. This raises the possibility that the government's compensation expenditure could potentially be either reduced or re-allocated to landowners who will not voluntarily take conservation action. Increasing participation in conservation incentive programs and minimizing the welfare losses associated with meeting conservation targets may be best achieved by offering programs that allow flexibility in terms of legal arrangements and other program attributes.  相似文献   
143.
利用遥感技术对矿区生态环境进行评价是一种新兴的、快速有效的方法.选取肥城矿区为研究区,利用Landsat ETM+遥感影像,通过计算机自动计算与手工屏幕矢量化相结合的方式进行遥感信息提取,统计出肥城矿区各土地利用类型的面积和河流长度.根据统计信息计算各类生态指数,对肥城矿区进行生态环境评价.评价结果显示,肥城矿区生态环境等级为良,基本适合人类生存.  相似文献   
144.
通过对世界自然遗产武陵源风景区学生消费市场的调查分析,掌握武陵源风景区学生市场开发现状,对其所采取的学生市场开发策略的效果与存在的问题进行了分析,提出进一步开发学生市场的对策,为武陵源及其他风景区的学生市场开发提供一定的依据.  相似文献   
145.
Acquisition of land rights has become a primary tool used to protect terrestrial biodiversity. Fixed length contracts are often used when trying to secure conservation benefits on private land in agri-environment schemes and payment for environmental services schemes, but the duration of the conservation contracts used in different programmes varies. To date, very little research has been undertaken to determine the situations in which contracts of differing lengths are optimal or when conservation agencies or groups should use a portfolio of different contract lengths rather than relying on a single type. Using stochastic dynamic programming and related heuristic methods, we investigate how the choice between short or long conservation contracts is affected by uncertainty regarding the future availability of sites and their ecological condition. We also examine the benefits offered by using a portfolio of different contract lengths. Conservation agencies must pay private landowners a premium to secure longer agreements and because of this, shorter contracts are advantageous if sites are likely to remain available for conservation in the future. Long contracts are preferred when future site availability becomes more unlikely. In contrast to uncertainty over site availability, uncertainty over future ecological conditions has little effect on contract selection and only markedly influences the choice between short and long contracts when there is heterogeneity across sites in expected conservation outcomes and future availability of sites is also uncertain. Finally, when future site availability is unlikely, the use of a portfolio of short and long contracts would offer greater conservation gains than using either type in isolation, even though this option is not yet one that is commonly found in conservation practice.  相似文献   
146.
Forecasting the temporal trend of a focal species, its range expansion or retraction, provides crucial information regarding population viability. To this end, we require the accumulation of temporal records which is evidently time consuming. Progress in spatial data capturing has enabled rapid and accurate assessment of species distribution across large scales. Therefore, it would be appealing to infer the temporal trends of populations from the spatial structure of their distributions. Based on a combination of models from the fields of range dynamics, occupancy scaling and spatial autocorrelation, here I present a model for forecasting the population trend solely from its spatial distribution. Numerical tests using cellular automata confirm a positive correlation, as inferred from the model, between the temporal change in species range sizes and the exponent of the power-law scaling pattern of occupancy. The model is thus recommended for rapid estimation of species range dynamics from a single snapshot of its current distribution. Further applications in biodiversity conservation could provide a swift risk assessment, especially, for endangered and invasive species.  相似文献   
147.
Including the distance species are able to move in predictive models improves conservation practice. Bird inventory projects carried out from 1993 to 2004 in Taiwan provide an opportunity to investigate the relationships among species distribution, movement distance, and the environment. We compared projected distributions of 17 Taiwanese endemic bird species using what we called the Standard Method (i.e. movement distance is zero) and what we called the Buffer Method (i.e. movement distance is longer than zero) in three presence-only models (GARP, MAXENT and LIVES). The Standard Method used species original occurrence records directly while the Buffer Method expanded the occurrence of species to areas 1 km2 around each recorded location. We first tested the efficacy of the Buffer Method using ten common species of the 17, and then applied the method to two rare species of the 17. For both the common and rare species, the distributions predicted by the two methods showed slight but important differences. The Buffer Method for all species had a higher average predictive probability, while the Standard Method had a higher maximum predictive probability. Most of the values for the area under the curve (AUC) were over 0.8 with the exceptions of Taiwan Barbet (Megalaima nuchalis) and Taiwan Hwamei (Garrulax taewanus), which have recently separated from Indochinese Barbet (Megalaima annamensis) and Chinese Hwamei (Garrulax canorus), and since 2008 and 2006 have been regarded as species endemic to the study area. Kappa values showed good performance for all species using both methods. The Buffer Method, however, resulted in significantly higher sensitivity and accuracy values for all models of species (p < 0.05). We conclude that when modeling species distribution including the area where the species was censused along with areas within the minimum movement areas better defines the surrounding areas that might supplement core habitat requirements. Therefore, using the Buffer Method, species surrounding distribution can be obtained which provides a better understanding of the species distributions. Given that distribution size is a key to the conservation of species, we suggest the Buffer Method can be used in conservation planning.  相似文献   
148.
It is becoming increasingly popular to consider species interactions when managing ecological foodwebs. Such an approach is useful in determining how management can affect multiple species, with either beneficial or detrimental consequences. Identifying such actions is particularly valuable in the context of conservation decision making as funding is severely limited. This paper outlines a new approach that simplifies the resource allocation problem in a two species system for a range of species interactions: independent, mutualism, predator-prey, and competitive exclusion. We assume that both species are endangered and we do not account for decisions over time. We find that optimal funding allocation is to the conservation of the species with the highest marginal gain in expected probability of survival and that, across all except mutualist interaction types, optimal conservation funding allocation differs between species. Loss in efficiency from ignoring species interactions was most severe in predator-prey systems. The funding problem we address, where an ecosystem includes multiple threatened species, will only become more commonplace as increasing numbers of species worldwide become threatened.  相似文献   
149.
将GIS与层次分析法相结合应用于渝西地区生态环境质量综合评价。首先,根据渝西地区生态环境的基本特点确定生态环境质量综合评价的指标体系和基本评价单元,通过层次分析法,确定各评价指标的权重,计算出每个评价单元的生态环境质量综合指数和分指数;然后运用GIS技术,根据每个评价单元的质量指数和分指数,自动生成渝西地区生态环境综合评价等级图;在此基础上,对渝西地区生态环境整体及各不同侧面质量状况的空间分异规律进行分析和研究。结果显示,渝西区生态环境质量基本上由南向北逐渐降低,与自然环境状况的空间格局大体吻合,但局部地区有差异。表明自然条件对渝西地区生态环境质量的空间分异起决定性作用,但社会经济和环境污染等因素同样对生态环境具有重要影响,在某些情况下,甚至可以成为决定因素,并在一定程度上改变生态环境的空间格局。  相似文献   
150.
粤港澳大湾区污染场地土壤风险管控制度体系建设与思考   总被引:6,自引:1,他引:5  
防范污染场地环境风险和保障人居环境安全是粤港澳大湾区建设世界级城市群面临的重要挑战和工作内容之一.由于粤港澳在政治制度和土地管理等方面的差异,以及珠三角9市内部城市化水平、产业结构以及环境管理能力的差别,大湾区各地污染场地风险管控模式有明显的差异,分析粤港澳大湾区典型城市污染场地风险管控特点,对加强污染场地风险管控技术交流与合作,优化大湾区污染场地风险管控制度具有重要意义.本文在简述我国污染场地风险管控制度体系的基础上,重点介绍了广州、深圳、东莞、香港和澳门的污染场地风险管控制度体系、监管对象、污染评估与整治程序等的特点,对其风险管控制度体系进行了分析与对比,并针对土地规划、政策反馈、信息公开及联盟机制探索等提出了思考与建议.总体来看,香港及珠三角部分地市构建了行之有效的污染场地风险管控制度体系,且体现了一定的地方特点,但随着污染场地的进一步开发再利用,打造粤港澳大湾区世界级城市群的建设目标将对污染场地风险管控策略的安全性、精细化和时效性等提出更高的要求,互相借鉴和充分学习,加强大湾区2区9市污染场地风险管控上的技术交流与合作,是实现大湾区污染场地安全再利用与高效开发的有效路径.  相似文献   
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