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221.
Qihua Shan Yuanchun Yu Jian Yu Jinchi Zhang 《Frontiers of Environmental Science & Engineering in China》2008,2(2):218-223
To reveal the biological characteristics of urban forest soil and the effects of soil enzyme on soil fertility as well as
the correlation between physicochemical properties and enzyme activities, 44 urban forest soil profiles in Nanjing were investigated.
Basic soil physicochemical properties and enzyme activities were analyzed in the laboratory. Hydrogen peroxidase, dehydrogenase,
alkaline phosphatase, and cellulase were determined by potassium permanganate titration, TTC (C19H15N4·Cl) colorimetry, phenyl phosphate dinatrium colorimetry, and anthrone colorimetry, respectively. The result showed that soil
pH, organic carbon (C), and total nitrogen (N) had great effects on hydrogen peroxidase, dehydrogenase, and alkaline phosphatase
activities in 0–20 cm thick soil. However, pH only had great effect on hydrogen peroxidase, dehydrogenase, and alkaline phosphatase
activities in 20–40 cm thick soil. Hydrogen peroxidase, dehydrogenase, and alkaline phosphatase were important biological
indicators for the fertility of urban forest soil. Both in 0–20 cmand 20–40 cmsoil, soil enzyme system (hydrogen peroxidase,
dehydrogenase, alkaline phosphatase, and cellulase) had a close relationship with a combination of physicochemical indicators
(pH, organic C, total N, available K, available P, cation exchange capacity (CEC), and microbial biomass carbon (Cmic)). The more soil enzyme activities there were, the higher the fertility of urban forest soil.
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Translated from Urban Environment & Urban Ecology, 2007, 20(4): 4–6, 9 [译自: 城市环境与城市生态] 相似文献
222.
运用STATA统计分析工具,将动态因子分析法应用到旅游业竞争力研究中,借助该方法从纵向和横向分析四川省旅游业竞争力情况,通过分析,重在了解四川省旅游业的发展变化及在全国的地位,为其今后制定有效的旅游业发展战略提供参考。结果表明:运用动态因子分析评价四川省旅游业竞争力客观可行,结果较切合实际。从横向来看,四川省旅游业竞争力在全国处于上游水平,说明综合实力较强;从纵向来看,2006~2010年四川省旅游业竞争力发生明显变化,主要是由于2008年汶川地震造成的影响。进一步提出四川省应注重从5个方面提升旅游业竞争力,即社会经济环境、旅游接待能力和市场、旅游资源、技术人才和生态环境 相似文献
223.
在当前中国经济快速增长和市场化改革逐步推进的过程中,始终面临着较为严重的土地违法问题;土地违法行为的主体不仅包括企事业单位和令人,更涉及各级地方政府以及农村集体组织.为深入了解经济增长与市场化改革对不同主体土地违法行为的影响,本文进行了初步的理论探讨,并运用全国层面的统计数据开展了相应的实证分析.结果表明,随着经济增长速度的加快,政府和企业的土地违法面积均显著增加;而土地市场化水平的提高则能有效减少土地违法的案件数.进一步地,经济增长和市场化改革对各级政府以及企事业单位、个人和农村集体组织土地违法行为的影响也存在一定的差异.本文的研究也指出,为有效控制土地违法行为的扩大,中国政府仍需采取转变经济增长方式、稳步推进市场化改革、引导企事业单位有序用地和不断完善土地督察制度等措施. 相似文献
224.
Abstract Nowa days, ecological and cultural tourism, especially those ancient villages and towns in China, have attracted an increasing number of tourists because of their unique cultural features. However, rapid development of tourism brings economic benefits, but results in a series of problems that threaten further tourism development and protection of ancient towns, such as over-commercialization and tourism urbanization. Taking Longmen ancient town as an example, this paper presented a sustainable way of preserving and developing resources of ancient villages and towns. First, identify cultural features and the extent of ancient villages and towns, and find the approach through which a cultural landscape zoning can be applied. Second, define a cooperative function area to release the pressure on core areas and protect their authentic cultures by extending tourism space. Third, balance tourism development with traditional industries to enhance the sustainability of community economies. 相似文献
225.
Abstract In recent years, with the rapid development of the tourist industry, world heritage sites become more and more popular among tourists from home and abroad. Therefore, heritage tourism has become a new hotspot. However, while world heritage sites are making obvious economic benefit from tourism, they also bring various problems and contradictions, of which the most troublesome one is the contradiction between heritage conservation and tourism development. To discuss and analyze the root and the essence of the above contradiction and find a way to bring about harmony between them is an important program faced by our national heritage management practice and academic research. Based on the case of cleaning the Temple and Cemetery of Confucius and the Kong Family Mansion in Qufu, this paper analyzes the reasons why our national world cultural heritage sites bring about the above contradiction in the process of tourism development and points out that the improper system and stakeholders' benefit imbroglio are respectively the root and the essence of the contraction. Then, it also puts forward corresponding solutions. 相似文献
226.
Bianfang Li 《中国人口.资源与环境(英文版)》2013,11(4):354-360
In this study, data envelopment analysis is used to measure the tourism efficiency of 31 regions in China according to the panel data from the year 2000 to 2010. The conclusion shows that the efficiency of tourism industry is on the rise as a whole, while the diversity of every region becomes more and more apparent. High efficiency appears in east regions like Beijing, Tianjin and Shanghai where the economy is developed, and regions like Jilin, Sichuan and Gansu in the midland and west show low efficiency. 相似文献
227.
Mountain biking is an increasingly popular, but sometimes controversial, activity in protected areas. Limited research on its impacts, including studies comparing biking with hiking, contributes to the challenges for mangers in assessing its appropriateness. The impacts of mountain bike riding off trail were compared to those of hiking on subalpine grassland in Australia using a modification of a common trampling experimental methodology. Vegetation and soil parameters were measured immediately and two weeks after different intensities of mountain biking (none, 25, 75, 200 and 500 passes across slope, 200 pass up and down slope) and hiking (200 and 500 passes across slope). There were reductions in vegetation height, cover and species richness, as well as changes in species composition and increases in litter and soil compaction with riding. Riding up and down a moderate slope had a greater impact than riding across the slope. Hiking also affected vegetation height, cover and composition. Mountain biking caused more damage than hiking but only at high use (500 passes). Further research including other ecosystems, topography, styles of riding, and weather conditions are required, but under the conditions tested here, hiking and mountain biking appear to be similar in their environmental impacts. 相似文献
228.
229.
合理科学的开发模式既能够深化旅游开发研究,又能够对旅游开发实践加以正确引导.在解读乡村旅游已有开发模式的基础上,较全面地阐释了社区-景区共生模式的内涵、演化过程以及模式构成,梳理了社区-景区共生模式的基本运作过程,并对该模式的效益进行评估. 相似文献
230.
陕西省作为我国的旅游资源大省,通过着力发展比较优势明显的旅游产业来促进县域经济发展本是大势所趋,但目前旅游业与工农业发展的孤立性又是约束县域经济发展的一道"紧箍咒",如何在旅游大发展的背景下实现旅游产业与县域经济的互动发展具有极为重要的理论与实证意义.通过分析华阴市2002--2009年旅游产业对县域经济的贡献能力,切实考虑当前该市县域经济发展中存在的主要问题,从旅游产业的视角出发,归纳出陕西旅游资源丰富地区县域经济发展的模式,以期为陕西省县域经济的发展提供对策和建议. 相似文献