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131.
132.
Altun L Baskent EZ Gunlu A Kadiogullari AI 《Environmental monitoring and assessment》2008,137(1-3):149-161
The productivity of forest sites has been indirectly determined with solo wood production objective in forest management.
Forest site productivity should, however, be determined directly in order to implement ecosystem based multipurpose forest
management philosophy. This article tackles the problem in distinguishing and mapping forest sites using both direct method
and indirect method in Genya Mountain located in central of Artvin State Forest Enterprise. About 112 sample plots were designed
and distributed over the area. In each sample plot, soil samples were collected and the classical timber inventory measurements
were taken. According to direct method, Soil Moisture Regime (SMR) method is preferred due to a water deficiency in the study
area. Water holding capacity was used as an essential criterion for the classification of the forest site. Forest site classifications
were assigned regarding the physiographic factors such as landform, aspect, and slope. Five different forest sites classes;
dry, moderate fresh, fresh, humid and hygric were determined. According to direct method, the guiding curve was used to generate
anamorphic site index (SI) equations and three site index classes; good (SI=I–II), medium (SI=III) and low (SI=IV–V) were
determined. Some important differences between the methods were realized. The forest sites determined with site index estimation
method indicate that site index I and II is 505.99 ha, III 1095.79 ha and IV and V 992.95 ha, whereas forest sites determined
with direct method related to dry site of 937.58 ha, moderate fresh site of 931.90 ha, fresh site of 1,797.71 ha, humid site
of 80.48 ha and hygric site of 356.55 ha. The forest site maps of both methods were created using GIS functions. The forest
sites of open and degraded areas should be determined according to direct method. 相似文献
133.
应用斑马鱼和凡纳对虾诊断污染场地污水的生物毒性 总被引:3,自引:1,他引:2
应用斑马鱼(Brachydanio rerio)和凡纳对虾(Penaeus vannamei)对某废弃有机污染场地中有毒有机废弃物堆积产生的污水(1号塘污水)和场地及周边地表径流积水(2号塘污水)的生物毒性进行了试验.结果表明,1号塘污水对斑马鱼和凡纳对虾96 hLC50分别为46.2%和59.6%, 2号塘污水的毒性试验中两种试验生物的死亡率皆为0.化学检测表明,1号塘污水中的主要污染物为苯酚类和酞酸脂类物质,而2号塘污水中均未检出有机污染物.化学检测结果与毒性试验结果具有较好的相关性. 相似文献
134.
135.
系统化、自然化、经济化、人性化—城市人居环境规划方法的生态转型 总被引:40,自引:0,他引:40
王如松 《城市环境与城市生态》2001,14(3):1-5
讨论了城市环境问题的生态学实质,国际城市人居环境生态学研究动向,以及城市人居环境建设的生态转型方法,重点介绍了城市人居环境规划中的系统化,自然化,经济化,人性化趋势,并从观念与目标的转型,规划与设计的转型和技术与材料革新等方面探讨了城市生态建设的转型方法。 相似文献
136.
Mercury concentrations are usually significant in historic Hg mining districts all over the world, so the atmospheric environment is potentially affected. In Asturias, northern Spain, past mining operations have left a legacy of ruins and Hg-rich wastes, soils and sediments in abandoned sites. Total Hg concentrations in the ambient air of these abandoned mine sites have been investigated to evaluate the impact of the Hg emissions. This paper presents the synthesis of current knowledge about atmospheric Hg contents in the area of the abandoned Hg mining and smelting works at ‘La Peña–El Terronal’ and La Soterraña, located in Mieres and Pola de Lena districts, respectively, both within the Caudal River basin. It was found that average atmospheric Hg concentrations are higher than the background level in the area (0.1 μg Nm?3), reaching up to 203.7 μg Nm?3 at 0.2 m above the ground level, close to the old smelting chimney at El Terronal mine site. Data suggest that past Hg mining activities have big influences on the increased Hg concentrations around abandoned sites and that atmospheric transfer is a major pathway for Hg cycling in these environments. 相似文献
137.
Philip M. Fearnside 《Environmental management》1997,21(4):553-570
138.
Kaufman MM 《Environmental management》2000,26(1):89-97
/ To test the effectiveness of Michigan's soil erosion control law, 30 construction sites were evaluated in the east-central part of the state. The analytical framework lumped nine best management practices (BMPs) most closely related to the law into three categories: slope stabilization, soil stabilization, and water management. All sites were in the land clearing or foundation/framing stage of construction and were evaluated within 2 days after a rainfall event. Only four of the sites performed above the mean of the scoring scale, with the categorical scoring of BMPs indicating the worst performance for slope stabilization measures. The poor results suggest a failure to integrate scientific knowledge of erosion control with policy. A fundamental problem is the lack of basic site data on soil, topography, and hydrology, resulting in the incorrect application of BMPs, such as staging, filter fences, and berms. The current institutional framework for soil erosion control also provides disincentives to mitigate local erosion problems. 相似文献
139.
VOCs污染场地挖掘过程的环境健康风险评价 总被引:1,自引:0,他引:1
开展了在典型污染场地修复过程中VOCs散逸浓度检测实验,并且建立了3条暴露途径对修复过程进行健康风险评价.结果表明,单污染物多途径累计非致癌指数最高的是四氯化碳,高达8.86E+01,其对综合非致癌影响贡献率为74.45%.多污染物质同一暴露途径危害指数最高的是呼吸暴露途径:1.01E+02,占综合危害指数的84.87%,非致癌综合危害指数为1.19E+02.单污染物多途径累计致癌指数最高的是1,2-二氯乙烷:3.08E-02,其对综合致癌影响贡献率为69.53%.多污染物质同一暴露途径危害指数最高的是呼吸暴露途径:3.96E-02,占综合致癌指数的89.39%,总致癌危害指数达到4.43E-02. 相似文献
140.
生活垃圾填埋场在施工期和运营期会产生废气、废水、噪声等环境污染,本研究结合监理行业现状和城市生活垃圾填埋场建设项目的特点,重点探讨了项目施工期和运营期环境监理的内容与方法。 相似文献