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191.
以宝应县有机产业发展为主要研究对象,通过对宝应县的自然资源、经济发展基础以及社会、技术、政策等因素的分析,阐述了宝应县发展有机产业的优、劣势,并就如何开展有机食品基地县的创建工作,提出了对策建议。 相似文献
192.
黄石市环境信息管理系统的开发与应用 总被引:3,自引:0,他引:3
从开发和应用的角度,详细阐述了在WebGIS技术支撑下,利用Java编程语言的方法开发出的黄石市环境信息管理系统开发的技术路线,体系结构,数据组织和系统模块的构建,该系统能够更好地降低环境空间数据采集成本,提高环境信息的共享程序和范围,实现污染源信息的实时查询和统计分析,提供多种总量控制的解决方案和多种专题图的编辑与管理工具,具有海量图库管理和模糊查询定位能力,此系统的建立,对于解决黄石市环境污染问题具有极大的社会效益和经济效益。 相似文献
193.
宁东能源化工基地规划产业布局的生态适宜性分析 总被引:3,自引:0,他引:3
基于遥感和地理信息系统技术,在宁东地区土壤侵蚀敏感性评价的基础上,对宁东能源化工基地规划的产业布局进行了生态适宜性分析.结果表明,宁东能源化工基地规划的煤炭、电力和煤化工三大主导产业布 局与该区生态环境不相适宜.在规划的12座煤矿、7个电厂和3个煤化工园区中,有3座煤矿、2个电厂和1个化工园区位于土壤侵蚀的高度敏感区内;有2座煤矿、3个电厂和1个化工园区位于土壤侵蚀的中度敏感区内.为更好的促进区域生态环境与经济社会的协调发展,探索性地提出了宁东能源化工基地产业布局规划的优化调整建议. 相似文献
194.
疏水性有机物和有机酸碱溶解度的估算 总被引:1,自引:2,他引:1
本文从理论上建立了疏水性有机物和任意pH条件下有机酸碱溶解度的估算方法,并估算了不同类型有机物的溶解度,和实测值比较,结构和辛醇相近的有机物吻合较好;结构不同,则有一定的偏差,这是由于假设有机物在辛醇中的活度系物等于1所致。经校正后得到了较好的结果。 相似文献
195.
中国土壤科学发展的理论与实践 总被引:12,自引:3,他引:12
从土壤作为资源与环境共同载体这一角度出发,阐述了土壤科学发展的特点、土壤科学研究的特性和方向,提出了土壤“3P”、土壤“3S”和土壤“3R”的未来创新研究内容。认为应牢牢把握“土壤圈”这一现代土壤科学发展的理论基础,丰富和发展现代土壤科学,不断推进土壤科学发展与创新的实践运用。 相似文献
196.
Sarah M. Buckley Ruth H. Thurstan Andrew Tobin John M. Pandolfi 《Conservation biology》2017,31(6):1322-1332
Aggregations of individual animals that form for breeding purposes are a critical ecological process for many species, yet these aggregations are inherently vulnerable to exploitation. Studies of the decline of exploited populations that form breeding aggregations tend to focus on catch rate and thus often overlook reductions in geographic range. We tested the hypothesis that catch rate and site occupancy of exploited fish‐spawning aggregations (FSAs) decline in synchrony over time. We used the Spanish mackerel (Scomberomorus commerson) spawning‐aggregation fishery in the Great Barrier Reef as a case study. Data were compiled from historical newspaper archives, fisher knowledge, and contemporary fishery logbooks to reconstruct catch rates and exploitation trends from the inception of the fishery. Our fine‐scale analysis of catch and effort data spanned 103 years (1911–2013) and revealed a spatial expansion of fishing effort. Effort shifted offshore at a rate of 9.4 nm/decade, and 2.9 newly targeted FSAs were reported/decade. Spatial expansion of effort masked the sequential exploitation, commercial extinction, and loss of 70% of exploited FSAs. After standardizing for improvements in technological innovations, average catch rates declined by 90.5% from 1934 to 2011 (from 119.4 to 11.41 fish/vessel/trip). Mean catch rate of Spanish mackerel and occupancy of exploited mackerel FSAs were not significantly related. Our study revealed a special kind of shifting spatial baseline in which a contraction in exploited FSAs occurred undetected. Knowledge of temporally and spatially explicit information on FSAs can be relevant for the conservation and management of FSA species. 相似文献
197.
A spatially explicit estimate of the prewhaling abundance of the endangered North Atlantic right whale
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Sophie Monsarrat M. Grazia Pennino Tim D. Smith Randall R. Reeves Christine N. Meynard David M. Kaplan Ana S.L. Rodrigues 《Conservation biology》2016,30(4):783-791
The North Atlantic right whale (NARW) (Eubalaena glacialis) is one of the world's most threatened whales. It came close to extinction after nearly a millennium of exploitation and currently persists as a population of only approximately 500 individuals. Setting appropriate conservation targets for this species requires an understanding of its historical population size, as a baseline for measuring levels of depletion and progress toward recovery. This is made difficult by the scarcity of records over this species’ long whaling history. We sought to estimate the preexploitation population size of the North Atlantic right whale and understand how this species was distributed across its range. We used a spatially explicit data set on historical catches of North Pacific right whales (NPRWs) (Eubalaena japonica) to model the relationship between right whale relative density and the environment during the summer feeding season. Assuming the 2 right whale species select similar environments, we projected this model to the North Atlantic to predict how the relative abundance of NARWs varied across their range. We calibrated these relative abundances with estimates of the NPRW total prewhaling population size to obtain high and low estimates for the overall NARW population size prior to exploitation. The model predicted 9,075–21,328 right whales in the North Atlantic. The current NARW population is thus <6% of the historical North Atlantic carrying capacity and has enormous potential for recovery. According to the model, in June–September NARWs concentrated in 2 main feeding areas: east of the Grand Banks of Newfoundland and in the Norwegian Sea. These 2 areas may become important in the future as feeding grounds and may already be used more regularly by this endangered species than is thought. 相似文献
198.
J. A. Camiñas N. Cano D. Cortés V. Díaz del Río A. García J. P. Rubín 《Journal of Coastal Conservation》1998,4(1):43-50
In October 1992, the Oceanographic Centre of Málaga of the Spanish Oceanographical Institute (IEO) started a monitoring project,Ecomálaga, which collects physical, chemical, biological and sedimentological data from the Alborán Sea shelf. The project is coordinated
with similar projects in the Atlantic and Mediterranean Centres of IEO. The ultimate objective is to, understand the long-term
changes of the essential marine-environmental parameters.
So far, nine quarterly surveys have been carried out—from October 1992 to December 1994. The following variables were registered:abiotic: location weather, water temperature, salinity, pH, dissolved oxygen, chlorophyll a, nitrate, nitrite, phosphate, silicate,biotic: zooplankton biomass and species composition, and ichthyoplankton. The granulometric composition and organic matter content
of sediments are also included.
Data are stored in a computerized data base named Ecomálaga Data Base, with contributions from geology, physics, plankton
biology and marine chemistry. The data base not only contains separate files for each research topic, but also allows for
interchange between these files, resulting in a synoptic data output. It offers the users an output in the form of synthetic
records of each station sampled.
The analysis of the data indicates seasonal influences and ainshore-offshore gradient, as well as an Atlantic influence on
the stations located in the transect closest to the Strait of Gibraltar. 相似文献
199.
通过对海南椰子生产现状的分析,本文指出了建立优质良种椰子种苗生产示范基地的必要性和重要性,并针对一些需要解决的问题,提出了加快海南椰子产业发展的建议。 相似文献
200.
Caitlin D. Kuempel Vivitskaia J. D. Tulloch Alyssa L. Giffin B. Alexander Simmons Valerie Hagger Carol Phua Ove Hoegh-Guldberg 《Conservation biology》2022,36(3):e13856
Conserving coral reefs is critical for maintaining marine biodiversity, protecting coastlines, and supporting livelihoods in many coastal communities. Climate change threatens coral reefs globally, but researchers have identified a portfolio of coral reefs (bioclimatic units [BCUs]) that are relatively less exposed to climate impacts and strongly connected to other coral reef systems. These reefs provide a proactive opportunity to secure a long-term future for coral reefs under climate change. To help guide local management efforts, we quantified marine cumulative human impact (CHI) from climate, marine, and land pressures (2013 and from 2008 to 2013) in BCUs and across countries tasked with BCU management. Additionally, we created a management index based on common management measures and policies for each pressure source (climate, marine, and land) to identify a country's intent and commitment to effectively manage these pressures. Twenty-two countries (79%) had increases in CHI from 2008 to 2013. Climate change pressures had the highest proportional contribution to CHI across all reefs and in all but one country (Singapore), but 18 BCUs (35%) and nine countries containing BCUs (32%) had relatively high land and marine impacts. There was a significant positive relationship between climate impact and the climate management index across countries (R2 = 0.43, p = 0.02), potentially signifying that countries with greater climate impacts are more committed to managing them. However, this trend was driven by climate management intent in Fiji and Bangladesh. Our results can be used to guide future fine-scale analyses, national policies, and local management decisions, and our management indices reveal areas where management components can be improved. Cost-effectively managing local pressures (e.g., fishing and nutrients) in BCUs is essential for building a climate-ready future that benefits coral reefs and people. 相似文献