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241.
长江流域土地资源情势及其发展战略对策   总被引:1,自引:1,他引:0  
土地资源对国民经济和社会发展十分重要,在一些地区已成为制约因素。本文着重对长江流域土地资源情势进行分析,指出该流域的特点是:土地资源绝对量大,人均占有量少;土地资源态势优劣并存;土地资源形势喜忧相伴。同时提出如下几个战略对策:1.实行开源与节流并重的方针,走节约型农业发展道路;2.增加农业投资,改土治水,集约经营;3.统一规划,优势互补,联合协作,共同发展;4.完善土地法制建设,健全土地资源预测预报工作。  相似文献   
242.
我国人口问题与社会持续发展   总被引:3,自引:0,他引:3  
本文分析了我国人口的主要特点和人口问题,指出人口问题已成为我国社会、经济发展的重要制约因素,进而论述了人口与资源、环境、经济协调发展的基本原理和宏观对策  相似文献   
243.
试论改善发展的质量   总被引:2,自引:0,他引:2  
本文结合中国国情,从经济发展的目标、边界、途径等方面论述了改善发展质量的基本内涵,提出经济发展应以满足社会基本需要为目标,经济发展必须与环境和资源的承载力相适应,依靠科技进步是提高发展质量的根本途径,同时须不断改善经济的内部结构,走资源节。  相似文献   
244.
建国40多年来,淄博市的国民经济和社会事业迅速发展,已经成为一个以重工业为主体的重要工业城市。同时,随着经济规模的迅速扩大,人口、资源与环境三大问题越来越突出。面对这样的市情,淄博市采取各种措施,突出重点,集中力量主攻薄弱环节,严格控制人口增长,保护资源,综合整治污染,取得了很大成效,初步走上了经济和社会事业与人口、资源、环境协调发展的轨道。  相似文献   
245.
建设项目竣工环境保护验收监测的内涵、缺陷及对策   总被引:1,自引:0,他引:1  
在环境换取经济增长向环境优化经济增长转变的新形势下,应拓展建设项目环境保护设施竣工验收监洲的内涵.指出目前的竣工验收监测对工业生产型建设项目的制约因素考虑不周、忽视了"三同时"的全过程、忽视了非工业生产型建设项目和区域性开发项目、忽视了无组织排放污染源.提出要创新治理设施竣工验收监测理念、优化竣工验收监测方法、强化竣工验收生态监洲技术的研究、开展区域性建设项目的验收监测.  相似文献   
246.
水资源量与城市人口规模   总被引:3,自引:0,他引:3  
城市发展与水资源息息相关。为保证城市规模的合理性,应综合考虑城市的水资源储量。通过城市水资源量估算城市人口规模的方法,以广西钦州水源工程为例,从钦州现有的几个水资源量分析钦州城市可能达到的人口规模,说明城市水资源是影响城市发展规模的主要因素之一。  相似文献   
247.
Heterotrophic cultivation caused high level of ROS and high lipids accumulation. HMTC is the best culture strategy for improving the microalgal biomass. Chlorella sp. HQ had great nutrient removal capacity under five culture strategies. The effects of cultivation strategies (including autotrophic cultivation (AC), heterotrophic cultivation (HC), fed-batch cultivation (FC), heterotrophic+ autotrophic two-stage cultivation (HATC), and heterotrophic+ mixotrophic two-stage cultivation (HMTC)) on the growth and lipid accumulation of Chlorella sp. HQ and its total nitrogen (TN) and total phosphorus (TP) removal in secondary effluent were investigated in column photoreactors. The results showed that the TN and TP removal rates ranged between 93.72%–95.82% and 92.73%–100%, respectively, under the five different strategies. The microalgal growth potential evaluated by the maximal growth rate (Rmax) was in the order of HMTC>HC>FC>AC>HATC. The values of biomass, total lipid yield, triacylglycerols (TAGs) yield, and total lipid content of the microalga cultivated in the last 5 d increased significantly, but the TAGs productivities of the five strategies were lower than those in the first 7 d. Compared with all the other cultivation strategies, the TAGs productivity and yield after 12 d of cultivation under the heterotrophic condition reached the highest values accompanying the highest level of intracellular reactive oxygen species (ROS), in which the TAGs yield reached 40.81 mg/L at the end of the cultivation period. The peaks in TAGs yield and ROS level suggested that HC was beneficial for lipids accumulation via regulating the cellular redox status and exerting ROS stress on microalgal cells. In summary, HMTC was the best cultivation strategy for improving the microalgal biomass and HC was the best strategy for microalgal TAGs accumulation to produce biodiesel.  相似文献   
248.
Estimated anthropogenic Hg emission was 11.9 tons in Pearl River Delta for 2014. Quantifying contributions of emission sources helps to provide control strategies. More attentions should be paid to Hg deposition around the large point sources. Power plant, industrial source and waste incinerator were priorities for control. A coordinated regional Hg emission control was important for controlling pollution. We used CMAQ-Hg to simulate mercury pollution and identify main sources in the Pearl River Delta (PRD) with updated local emission inventory and latest regional and global emissions. The total anthropogenic mercury emissions in the PRD for 2014 were 11,939.6 kg. Power plants and industrial boilers were dominant sectors, responsible for 29.4 and 22.7%. We first compared model predictions and observations and the results showed a good performance. Then five scenarios with power plants (PP), municipal solid waste incineration (MSWI), industrial point sources (IP), natural sources (NAT), and boundary conditions (BCs) zeroed out separately were simulated and compared with the base case. BCs was responsible for over 30% of annual average mercury concentration and total deposition while NAT contributed around 15%. Among the anthropogenic sources, IP (22.9%) was dominant with a contribution over 20.0% and PP (18.9%) and MSWI (11.2%) ranked second and third. Results also showed that power plants were the most important emission sources in the central PRD, where the ultra-low emission for thermal power units need to be strengthened. In the northern and western PRD, cement and metal productions were priorities for mercury control. The fast growth of municipal solid waste incineration were also a key factor in the core areas. In addition, a coordinated regional mercury emission control was important for effectively controlling pollution. In the future, mercury emissions will decrease as control measures are strengthened, more attention should be paid to mercury deposition around the large point sources as high levels of pollution are observed.  相似文献   
249.
Species, habitats, and ecosystems are increasingly exposed to multiple anthropogenic stressors, fueling a rapidly expanding research program to understand the cumulative impacts of these environmental modifications. Since the 1970s, a growing set of methods has been developed through two parallel, sometimes connected, streams of research within the applied and academic realms to assess cumulative effects. Past reviews of cumulative effects assessment (CEA) methods focused on approaches used by practitioners. Academic research has developed several distinct and novel approaches to conducting CEA. Understanding the suite of methods that exist will help practitioners and academics better address various ecological foci (physiological responses, population impacts, ecosystem impacts) and ecological complexities (synergistic effects, impacts across space and time). We reviewed 6 categories of methods (experimental, meta-analysis, single-species modeling, mapping, qualitative modeling, and multispecies modeling) and examined the ability of those methods to address different levels of complexity. We focused on research gaps and emerging priorities. We found that no single method assessed impacts across the 4 ecological foci and 6 ecological complexities considered. We propose that methods can be used in combination to improve understanding such that multimodel inference can provide a suite of comparable outputs, mapping methods can help prioritize localized models or experimental gaps, and future experiments can be paired from the outset with models they will inform.  相似文献   
250.
Between 1990 and 2007, 15 southern white (Ceratotherium simum simum) and black (Diceros bicornis) rhinoceroses on average were killed illegally every year in South Africa. Since 2007 illegal killing of southern white rhinoceros for their horn has escalated to >950 individuals/year in 2013. We conducted an ecological–economic analysis to determine whether a legal trade in southern white rhinoceros horn could facilitate rhinoceros protection. Generalized linear models were used to examine the socioeconomic drivers of poaching, based on data collected from 1990 to 2013, and to project the total number of rhinoceroses likely to be illegally killed from 2014 to 2023. Rhinoceros population dynamics were then modeled under 8 different policy scenarios that could be implemented to control poaching. We also estimated the economic costs and benefits of each scenario under enhanced enforcement only and a legal trade in rhinoceros horn and used a decision support framework to rank the scenarios with the objective of maintaining the rhinoceros population above its current size while generating profit for local stakeholders. The southern white rhinoceros population was predicted to go extinct in the wild <20 years under present management. The optimal scenario to maintain the rhinoceros population above its current size was to provide a medium increase in antipoaching effort and to increase the monetary fine on conviction. Without legalizing the trade, implementing such a scenario would require covering costs equal to approximately $147,000,000/year. With a legal trade in rhinoceros horn, the conservation enterprise could potentially make a profit of $717,000,000/year. We believe the 35‐year‐old ban on rhinoceros horn products should not be lifted unless the money generated from trade is reinvested in improved protection of the rhinoceros population. Because current protection efforts seem to be failing, it is time to evaluate, discuss, and test alternatives to the present policy.  相似文献   
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