全文获取类型
收费全文 | 106篇 |
免费 | 3篇 |
国内免费 | 3篇 |
专业分类
安全科学 | 1篇 |
废物处理 | 2篇 |
环保管理 | 32篇 |
综合类 | 27篇 |
基础理论 | 28篇 |
污染及防治 | 6篇 |
评价与监测 | 7篇 |
社会与环境 | 8篇 |
灾害及防治 | 1篇 |
出版年
2023年 | 1篇 |
2022年 | 2篇 |
2021年 | 3篇 |
2020年 | 4篇 |
2019年 | 2篇 |
2018年 | 1篇 |
2017年 | 3篇 |
2016年 | 1篇 |
2015年 | 5篇 |
2013年 | 2篇 |
2012年 | 5篇 |
2011年 | 6篇 |
2010年 | 7篇 |
2009年 | 6篇 |
2008年 | 7篇 |
2007年 | 9篇 |
2006年 | 4篇 |
2005年 | 8篇 |
2004年 | 8篇 |
2003年 | 5篇 |
2002年 | 2篇 |
2001年 | 3篇 |
2000年 | 7篇 |
1999年 | 3篇 |
1998年 | 1篇 |
1997年 | 1篇 |
1994年 | 3篇 |
1991年 | 1篇 |
1987年 | 1篇 |
1984年 | 1篇 |
排序方式: 共有112条查询结果,搜索用时 15 毫秒
41.
Indicators of visual scale as predictors of landscape preference; a comparison between groups 总被引:1,自引:0,他引:1
Tveit MS 《Journal of environmental management》2009,90(9):2882-2888
Landscape change alters the visual scale of agricultural landscapes, as production units get larger and strips of taller vegetation are removed between smaller units. Visual scale, defined as the perceptual units reflecting the experience of landscape rooms, visibility and openness, is considered a key factor shaping landscape preference. The visual expression of landscapes affects people in many ways; aesthetic appreciation, health and well being. In order to understand how landscape changes alter the visual scale of landscapes, and hence its effect on human beings, it is important to establish efficient and practical ways of measuring visual scale and its relation to landscape preferences. This paper presents an empirical test of the ability to predict landscape preference of two photo-based indicators of visual scale; percentage open land in the view and size of landscape rooms. A preference survey was conducted with two groups of respondents; a student group from the Norwegian University of Life Sciences (UMB) and a public group. The student group was chosen to represent future landscape professionals. Photos of landscapes varying in the expression of visual scale were shown to survey respondents, who were asked to give scores according to how much they liked the landscapes. Both indicators were found to be predictors of preference for the student group, but not for the public group. The results demonstrate that student preferences do not reflect the landscape preferences of the wider public. The different appreciation of visual scale in the landscape of future landscape professionals and the public implies that experts wanting to reflect preferences of the wider public should be cautious when evaluating the visual impact of landscape change. 相似文献
42.
43.
电力工程建设场地设计地震动参数的研究 总被引:2,自引:1,他引:2
以江苏某电厂为例,采用概率法对其工程场地进行地震危险性分析,确定基岩水平向地震加速度时程,并根据场地土的静、动力性能参数的测试结果,采用等效线性化考虑土的非线性特性的影响,利用一维波动模型进行场地土层地震反应分析和地震动效应分析。文中得到了50年超越概率63%、10%和3%的地表水平向地震动峰值加速度和反应谱,将所得结果与电力工程相关规范作了一些比较,指出了相关规范中的一些不足,提出应对大型电力工程场地的设计地震动参数做专门的研究。 相似文献
44.
A. M. Rusanov 《Russian Journal of Ecology》2003,34(1):10-15
Changes in the properties and ecological functions of soils under the effect of farming are considered. Evidence is provided that optimization of the structure of land inventory with regard to environmental conditions in a concrete region is a promising approach to the conservation and restoration of disturbed and degraded soils. A classification of soils with respect to their arability is proposed as a theoretical basis for reorganizing agricultural land use. 相似文献
45.
嘉陵江流域坡耕地“生态农业旅游”垂直景观模式 总被引:4,自引:0,他引:4
从治理水土流失角度出发,提出了坡耕地“生态农业旅游”技术与示范。其垂直生态景观模式按坡度和等高线布置:在坡度大于25°的山坡顶形成水保林木区,坡上15°~25°的陡坡种植桃树,坡中5°~15°的斜坡种植枇杷,坡下小于5°的缓坡地带种植特种水果、瓜类及蔬菜,坡底形成“稻—鱼”和“藕—鱼”特色水域区。道路系统设计为环山而下的水泥主路、观景石板干路、埂边地界小路三级,道路两侧实施还林还草。“农家乐”型旅游接待自然分布在试验区内,同时在坡上建立旅游“一条街”、坡底试验旅游产业化经营。果园内实施多熟作物覆盖、间种套种。垂直生态景观产生了独特而丰富的景观效果,并具有较好的生态功能、经济功能和社会功能。 相似文献
46.
47.
Abstract: Ecological traps and other cases of apparently maladaptive habitat selection cast doubt on the relevance of density as an indicator of habitat quality. Nevertheless, the prevalence of these phenomena remains poorly known, and density may still reflect habitat quality in most systems. We examined the relationship between density and two other parameters of habitat quality in an open‐nesting passerine species: the Ovenbird (Seiurus aurocapilla). We hypothesized that the average individual bird makes a good decision when selecting its breeding territory and that territory spacing reflects site productivity or predation risk. Therefore, we predicted that density would be positively correlated with productivity (number of young fledged per unit area). Because individual performance is sensitive to events partly determined by chance, such as nest predation, we further predicted density would be weakly correlated or uncorrelated with the proportion of territories fledging young. We collected data in 23 study sites (25 ha each), 16 of which were located in untreated mature northern hardwood forest and seven in stands partially harvested (treated) 1–7 years prior to the survey. Density explained most of the variability in productivity (R2= 0.73), and there was no apparent decoupling between density and productivity in treated plots. In contrast, there was no significant relationship between density and the proportion of territories fledging ≥1 young over the entire breeding season. These results suggest that density reflects habitat quality at the plot scale in this study system. To our knowledge this is one of the few studies testing the value of territory density as an indicator of habitat quality in an open‐nesting bird species on the basis of a relatively large number of sizeable study plots. 相似文献
48.
49.
Bird and land-use surveys were conducted along the agricultural gradient covering from pure croplands through mixed-farming to pure pastoral-farming scenario in the Pampean region of Argentina. Simple regression analyses were performed to analyse the responses of bird abundance to the percentage of land devoted to crop-production. The specific variables associated to bird abundance within both the crop and pastoral-farming landscapes were identified by running redundancy analyses (RDA). The abundance of 20 out of 43 species (47%) was significantly related to the percentage of cropland, finding negative (65%), positive (25%) unimodal (5%) and bimodal (5%) responses of birds to increasing intensity of crop production. The results showed three types of negative and two types of positive responses of bird abundance to the agricultural gradient. RDA revealed the importance of crop-field types in the crop-production scenario and of cattle presence and grass height in the pastoral-farming scenario for the structuring of the grassland bird community. As most species were negatively affected by crop production, the current land-use homogenisation towards high-intensity croplands will most likely result in population decline of many birds in the region. 相似文献
50.
Seeking knowledge of traditional Indigenous burning practices to inform regional bushfire management
ABSTRACTA transdisciplinary review of the current academic knowledge of Indigenous traditional fire management is presented for the Mt Lofty Ranges in South Australia. For a long time, the roles of Indigenous management of the landscape have either been overlooked or discounted within environmental studies. That situation is beginning to change in many parts of Australia. However, this review of knowledge of traditional Indigenous burning practices specifically for the Mt Lofty Ranges suggests that there is very little formalised, academic knowledge available that could be utilised to inform prescribed burning practices in the region. Perhaps Indigenous peoples’ use of fire was strongly governed by individual choices, or perhaps established regimes demarcated roles across groups; perhaps some areas were burnt regularly and others were left unaltered – there is still no clear evidence from the academic literature to provide even limited understandings of such elements of pre-colonial fire regimes. That gap in knowledge will become increasingly problematic as the need for appropriate, sophisticated burning practices to respond to risk in peri-urban Adelaide increases with a changing climate. To learn from traditional Indigenous land management: (a) formal knowledge needs to be generated on past regional burning practices; and (b) understanding needs to be developed as to whether past burning practices could lead to effective hazard management and biodiversity outcomes within contemporary landscapes. Such an integration of Indigenous knowledge for effective environmental management will only be possible if the injustices of past exclusions of the importance of Indigenous biocultural practices are recognised. 相似文献