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361.
海峡西岸地区人为源大气污染物排放特征研究 总被引:2,自引:3,他引:2
采用以"自下而上"为主的方法建立了2007年海峡西岸地区的人为源大气污染物排放清单.计算结果显示,海西地区人为源SO2、NOx、CO、PM10、PM2.5、VOCs和NH3排放总量分别为69.5×104、96.1×104、413.1×104、93.9×104、40.6×104、85.0×104和28.5×104t.电厂和工业燃烧设施分别占SO2排放的48%和39%,以及NOx排放的51%和25%.水泥、砖瓦等制造过程贡献了约51%的PM10排放和36%的PM2.5排放.秸秆燃烧、加油站和涂料等VOCs面源分别占到其排放总量的27%、15%和4%.NH3的主要排放源为畜禽养殖和氮肥施用等农业部门,占到总排放量的89%.海西地区的单位面积大气污染物排放量仅相当于长三角地区的25%左右,略高于全国平均水平.该地区人为源和天然源VOCs排放比重分别占56%和44%,人为源VOCs排放比重低于全国大部分地区.海西大气污染高排放地区主要集中在沿海一带,以泉州、潮汕、福州和温州等地区为主,建议"十二五"发展过程中,重点关注上述高排放地区,限制重点排放源的发展,开发低耗能、低污染的发展模式. 相似文献
362.
363.
《Environmental Communication: A Journal of Nature and Culture》2013,7(2):231-254
Place branding strategies play a significant role in the professional composition of landscape imagery, including the depiction of “natural” landscapes. In this paper, Brand Blue Mountains, a brand currently implemented in the Blue Mountains region (Australia), is discursively analyzed. The brand sets out an all-encompassing “Vision” defining the identity, values and personality of the World Heritage listed Blue Mountains landscape, summarized in the tagline Elevate Your Senses. This “vision” is visually translated into a strictly coordinated and copyrighted suite of logos, graphic design, color, fonts and various photographic styles. Analysis reveals that the degree of control that place brand strategists seek to exert over the visual expression of landscape identity is significant. A highly selective narrative of positive nature-based sensory experience is constructed through the holistic application of contemporary visual media. The brands' communications strategy naturalizes and reinforces a particular market-friendly version of place. The framework that brands set for the representation of landscapes overall amounts to an exercise in calculated aesthetics, whereby the form and content of landscape images of various kinds is measured to achieve the greatest market differentiation and impact which technologies allow. The result of this calculated aesthetic system, with its taglines, saturated color, careful composition and magazine-format brevity, is a reduction in the complexity of landscape representations and a perpetuation of nature stereotypes. 相似文献
364.
社会实践的需要是推动法律发展进步的根本动力。我国西部大开发战略是从根本上解决少数民族地区贫困落后状况 ,实现各民族共同繁荣的重大决策。由于西部生态环境的脆弱性及其在全国生态环境中的重要性 ,使得“可持续发展战略”成为西部唯一的发展模式选择 ,突出生态环境的保护和建设 ,促进西部地区经济发展与生态的良性循环 ;必须制定一套适合西部少数民族地区经济社会整体发展的法律体系 ,并最终实现“立法的生态化”。 相似文献
365.
通过西部11省、市、自治区1997~2012年面板数据,对西部地区城镇化、贸易开放、经济增长、能源消费与碳排放之间的动态关系进行了研究。使用3种面板单位根检验方法,结果显示:所有变量都是一阶单整;Pedroni和Kao协整检验表明变量之间存在协整关系;通过FMOLS估计方法进行回归,结果发现经济增长、能源消费、贸易开放都对CO2排放产生正的影响;西部地区GDP平方与CO2的关系符合环境库兹涅茨曲线特征;城镇化对CO2产生负的影响。格兰杰因果关系检验显示,短期内,GDP、贸易开放是CO2的单向格兰杰原因;能源消费、城镇化是CO2的双向格兰杰原因;能源消费、贸易开放是GDP的双向格兰杰原因;贸易开放是能源消费的双向格兰杰原因。存在误差修正机制,当系统在短期内偏离长期均衡时,5个变量在调整过程中能发挥重要作用,使其重新回到均衡状态。最后,提出政策建议。 相似文献
366.
Emily Kindervater Alan D. Steinman 《Journal of the American Water Resources Association》2019,55(5):1183-1195
Phosphorus (P) and sediment inputs from agricultural drainage contribute to the development of hypereutrophic conditions in lakes across the world. Two‐stage (2‐S) ditches, an agricultural best management practice gaining acceptance in the Midwestern United States, increase floodplain area within drainage ditches to help capture nutrients and sediment. While denitrification has been shown to increase on 2‐S benches, less is known about their P retention ability. This study assessed the abiotic and biotic P retention of two separate 2‐S ditches compared to their corresponding traditional reaches directly upstream within the Macatawa watershed, located in West Michigan. Soluble reactive P export was significantly reduced in 2‐S baseflow of both ditch systems. Equilibrium P concentration values suggest retention of P within the 2‐S sediment. P was bound within stable fractions in both 2‐S and traditional reaches. An analysis of P stock within the ditches revealed sediment held over 96% of total P (TP) within each reach compared to <4% in bench vegetation and periphyton combined. Turbidity, but not TP, was reduced in one study ditch, whereas TP, but not turbidity, was reduced in the other study ditch. Geomorphic stability may have been responsible for differing P retention between ditches. Ability to retain P appears to be impacted by physical as well as biogeochemical characteristics; hence, structure and age of 2‐S reaches influence P retention. 相似文献
367.
西洞庭湖湿地鸟类群落组成、多样性及保护对策 总被引:1,自引:0,他引:1
采用固定样带法和样点法对湖南西洞庭湖自然保护区的鸟类群落进行了研究,共纪录到217种,隶属16目46科117属,其中冬候鸟113种、旅鸟1种、留鸟60种、夏候鸟43种,分别占5207%、046%、2765%、1982%;古北界种类102种 (占4700 %),东洋界种类 67种 (占3088%),广布型种类 48种 (占2212 %);国家Ⅰ级保护种类4种,国家Ⅱ级保护种类29种。鸟类群落多样性指数和均匀性指数分别为4886 5和0594 9。并分析其湿地鸟类的重要性和稀缺性,提出了相应的保护措施。 相似文献
368.
东祁连山土地利用方式对土壤持水能力和渗透性的影响 总被引:5,自引:1,他引:4
为了解祁连山东段天祝高寒地区不同土地利用方式对土壤持水能力和渗透性的影响,研究选取天然草地、退耕自然恢复地、燕麦地和多年生草地4种土地利用方式,研究了不同土地利用方式对土壤持水能力和渗透性的影响。结果表明,不同土地利用方式对土壤持水能力和渗透性影响显著。土壤容重大小依次为退耕自然恢复地(1.104 g/cm3)>多年生草地(1.061 g/cm3)>燕麦地(1.011 g/cm3)>天然草地(0.781 g/cm3);总孔隙度为天然草地(68.196%)>燕麦地(60.606%)>多年生草地(58.93%)>退耕自然恢复地(57.5%);土壤最大持水量和土壤稳渗速率天然草地最大(681.966 t/hm2和3.02 mm/min),退耕自然恢复地最小(575.005 t/hm2和1.004 mm/min)。从土壤持水性能和入渗性能来看,4种土地利用方式中天然草地最好,退耕自然恢复地最差,燕麦地和多年生草地土壤持水能力和渗透性能优于退耕自然恢复地。 相似文献
369.
Jan Weber Jana Klánová Crispin J. Halsall 《Environmental pollution (Barking, Essex : 1987)》2009,157(12):3308-3313
Here we investigate the photodegradation of structurally similar organophosphorus pesticides; methyl-parathion and fenitrothion in water (20 °C) and ice (−15 °C) under environmentally-relevant conditions with the aim of comparing these laboratory findings to limited field observations. Both compounds were found to be photolyzed more efficiently in ice than in aqueous solutions, with quantum yields of degradation being higher in ice than in water (fenitrothion > methyl-parathion). This rather surprising observation was attributed to the concentration effect caused by freezing the aqueous solutions. The major phototransformation products included the corresponding oxons (methyl-paraoxon and fenitroxon) and the nitrophenols (3-methyl-nitrophenol and nitrophenol) in both irradiated water and ice samples. The presence of oxons in ice following irradiation, demonstrates an additional formation mechanism of these toxicologically relevant compounds in cold environments, although further photodegradation of oxons in ice indicates that photochemistry of OPs might be an environmentally important sink in cold environments. 相似文献
370.
STEVEN R. EWING‡ RUEDI G. NAGER MALCOLM A. C. NICOLL† AURELIEN AUMJAUD‡§§ CARL G. JONES‡§ LUKAS F. KELLER†† 《Conservation biology》2008,22(2):395-404
Abstract: Many populations have recovered from severe bottlenecks either naturally or through intensive conservation management. In the past, however, few conservation programs have monitored the genetic health of recovering populations. We conducted a conservation genetic assessment of a small, reintroduced population of Mauritius Kestrel ( Falco punctatus ) to determine whether genetic deterioration has occurred since its reintroduction. We used pedigree analysis that partially accounted for individuals of unknown origin to document that (1) inbreeding occurred frequently (2.6% increase per generation; N eI = 18.9), (2) 25% of breeding pairs were composed of either closely or moderately related individuals, (3) genetic diversity has been lost from the population (1.6% loss per generation; N eV = 32.1) less rapidly than the corresponding increase in inbreeding, and (4) ignoring the contribution of unknown individuals to a pedigree will bias the metrics derived from that pedigree, ultimately obscuring the prevailing genetic dynamics. The rates of inbreeding and loss of genetic variation in the subpopulation of Mauritius Kestrel we examined were extreme and among the highest yet documented in a wild vertebrate population. Thus, genetic deterioration may affect this population's long-term viability. Remedial conservation strategies are needed to reduce the impact of inbreeding and loss of genetic variation in this species. We suggest that schemes to monitor genetic variation after reintroduction should be an integral component of endangered species recovery programs. 相似文献