全文获取类型
收费全文 | 865篇 |
免费 | 43篇 |
国内免费 | 165篇 |
专业分类
安全科学 | 39篇 |
废物处理 | 6篇 |
环保管理 | 196篇 |
综合类 | 371篇 |
基础理论 | 171篇 |
环境理论 | 2篇 |
污染及防治 | 151篇 |
评价与监测 | 16篇 |
社会与环境 | 83篇 |
灾害及防治 | 38篇 |
出版年
2023年 | 10篇 |
2022年 | 40篇 |
2021年 | 34篇 |
2020年 | 36篇 |
2019年 | 31篇 |
2018年 | 34篇 |
2017年 | 62篇 |
2016年 | 51篇 |
2015年 | 40篇 |
2014年 | 37篇 |
2013年 | 120篇 |
2012年 | 51篇 |
2011年 | 46篇 |
2010年 | 32篇 |
2009年 | 42篇 |
2008年 | 41篇 |
2007年 | 64篇 |
2006年 | 38篇 |
2005年 | 38篇 |
2004年 | 20篇 |
2003年 | 37篇 |
2002年 | 34篇 |
2001年 | 26篇 |
2000年 | 25篇 |
1999年 | 8篇 |
1998年 | 12篇 |
1997年 | 9篇 |
1996年 | 11篇 |
1995年 | 8篇 |
1994年 | 6篇 |
1993年 | 6篇 |
1992年 | 4篇 |
1991年 | 8篇 |
1990年 | 5篇 |
1989年 | 2篇 |
1988年 | 1篇 |
1982年 | 1篇 |
1980年 | 1篇 |
1979年 | 1篇 |
1973年 | 1篇 |
排序方式: 共有1073条查询结果,搜索用时 140 毫秒
251.
Karlah Rae Rudolph 《Local Environment》2013,18(9):1079-1098
A food crisis confronts many Indigenous communities in northwestern Canada, as reflected by wide-scale food insecurity and diet-related disease. South-generated responses to this crisis generally disregard principles of Indigenous food sovereignty and are disengaged from concerns related to environmental and food justice. This study seeks to explore the needs and priorities of a First Nation (Misipawistik Cree Nation) and an associated Métis community (Grand Rapids) regarding existing and potential responses to the food crisis in northern Manitoba. Substantial changes to the traditional food system were initiated during the establishment of the reserve system in the 1800s and now extend to damage associated with hydro development. Responses to these changes were categorised according to themes and include the revival of country food traditions, individual and community gardens, agriculture in the North, and better quality imported foods. Regardless of response, decision-making needs to be community-driven, culturally appropriate, to reflect local priorities in order to effectively address the northern food crisis, and, ultimately, needs to work towards Indigenous food sovereignty to be effective. 相似文献
252.
梳理了上海市在一次性塑料饭盒管理工作中回收处置系统难以正常运转的主要问题,提出了建立全国一盘棋的格局,将其他塑料废弃物纳入回收处置的管理范畴,并建立对废塑料回收处置的奖励或补贴政策,从而继续控制视觉污染,促进生活垃圾减量化和资源化。 相似文献
253.
Abstract: Marine protected areas (MPAs) are a popular conservation strategy, but their impacts on human welfare are poorly understood. To inform future research and policy decisions, we reviewed the scientific literature to assess MPA impacts on five indicators of human welfare: food security, resource rights, employment, community organization, and income. Following MPA establishment, food security generally remained stable or increased in older and smaller MPAs. The ability of most fishing groups to govern MPA resources changed. Increased resource rights were positively correlated with MPA zoning and compliance with MPA regulations. Small sample sizes precluded statistical tests of the impacts of MPAs on employment, community organization, and income. Our results demonstrate that MPAs shape the social well‐being and political power of fishing communities; impacts (positive and negative) vary within and among social groups; and social impacts are correlated with some—but not all—commonly hypothesized explanatory factors. Accordingly, MPAs may represent a viable strategy for enhancing food security and empowering local communities, but current practices negatively affect at least a minority of fishers. To inform policy making, further research must better document and explain variation in the positive and negative social impacts of MPAs. 相似文献
254.
Jerzy Falandysz Magdalena Gucia Aneta Mazur 《Journal of environmental science and health. Part. B》2013,48(6):735-740
The carpophores of Parasol Mushroom and underlying soil substrate collected from several unpolluted and spatially distant sites across Poland were examined to know content and bioconcentration potential of mercury by this species. The total mercury content of the caps of Parasol Mushroom for the particular sites ranged from 1.1 ± 1.0 to 8.4 ± 7.4 μ g/g dry matter (total range from 0.05 to 22 μ g/g dm), while in the stalks were from 0.53 ± 0.27 to 6.8 ± 7.1 μ g/g dm (total range from 0.078 to 20 μ g/g dm). A top soil layer (0–10 cm) showed baseline mercury concentration from 0.022 ± 0.011 to 0.36 ± 0.16 μ g/g dm (total range from 0.010 to 0.54 μg/g dm). Parasol Mushroom is an effective mercury accumulator in the carpophores and bioconcentration factor (BCF) values of this element in the caps and depending on the sampling site ranged from 16 ± 6 to 220 ± 110 (total range from 0.52 to 470), while for the stalks were from 7.6 ± 2.6 to 130 ± 96 (total range from 0.52 to 340). It seems reasonable to state that tolerance (maximum allowable concentration) of the total mercury in a single cap of Parasol Mushroom at unpolluted areas should not exceed 25 μ g/g dm. A value greater then 25 μ g/g dm will imply an elevated content due to site pollution problems. Nevertheless, knowledge on highly toxic methylmercury content and its fraction in the total mercury content of Parasol Mushroom is lacking. 相似文献
255.
This research conducted on municipal solid waste management for the first time quantified food spoilage as being 8.8% weight of all officially collected household garbage in the Brazilian city under study. The unexpected size of this waste fraction gave rise to work on the causes of waste and on its distribution over the product life cycle specific to fruit and vegetables. Waste was defined as being the combination of losses and scraps. Administrative shortcomings were identified as basic reasons for waste. At the producer and consumer ends of the cycle, negligence was shown to be the single most important problem. Fruit and vegetables deteriorate during the operations of handling, transport, packaging, storage, selling and consumption. The study detailed the occurrence of waste at all of these stages. In the medium-size Brazilian city, the total waste of fruit and vegetables was shown to amount to 16.6% weight in the marketing stage of the life cycle. At the consumer level, it was measured as 3.4% weight of all household garbage. Specific reasons for this waste were identified at the levels of producer, wholesaler and retailer. Short-term remedies were pointed out that invariably corrected deficient management procedures. It was shown that very simple administrative measures can significantly reduce the spoilage of fruit and vegetables. Long-term strategies involve the creation of sample cases for administration of the fruit and vegetables life cycle at all stages. 相似文献
256.
A Yin‐Yang approach to education policy regarding health and the environment: early‐careerists' image of the future and priority programmes
下载免费PDF全文
![点击此处可从《Natural resources forum》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Paul Watts Benjamin Custer Zhuang‐Fang Yi Enoch Ontiri Marivic Pajaro 《Natural resources forum》2015,39(3-4):202-213
Since the inception of sustainable development (SD), there has been a somewhat ignored contradiction between paradigms that are ecosystem‐based and paradigms that are human‐based or purely economic. We suggest that this contradiction can be unified through a balance of the two. The Chinese Yin‐Yang philosophy is applied as a tool or approach to seeking balance between these ecocentric and anthropocentric paradigms. Priority education policy design for the merging of ecology and health are projected through an Ecohealth lens in response to increasing SD challenges and the intention of the international Ecohealth organization to contribute to SD goals. Meeting SD goals along the nexus of health and environment is further considered through early‐careerist cultural assessments and projections. The groups considered for their professional image of the future are: members of the Ecohealth Association Student Section and Chinese early‐careerists participating in a related conference. In response to SD goals, a problem‐based learning design is suggested as an education policy priority. Rather than approaching SD as a boolean concept, for example, by either focusing on ecosystem sustainability or economic development, we suggest education policy for programmes and curriculums that will help emerging professionals balance these paradigms, so as to best address national and global challenges. 相似文献
257.
The resilience of Australia's food-supply chain following natural disasters has been brought into question, following the significant flooding and cyclone events of 2010/2011. How this manifests at the community level, in both rural and urban locations, has been examined through the lens of large and small food retailers in northern NSW. These interviews reveal the fragility of both the long and short supply chain where transport systems are compromised. Self-imposed standards severely restricted the ability of supermarkets to acquire fresh food, in the face of transport disruptions. Similarly, the precarious position of rural food retailers, exposed to continual fuel and electricity price increases, is compounded by the impact of extreme weather events. The insights captured through this study suggest interception points, or policy entry points, to address the resilience of the food-supply chain. 相似文献
258.
微量金属强化餐厨垃圾厌氧消化优化条件研究 总被引:1,自引:0,他引:1
采用L9(34)正交试验,研究了CoCl2·6H2O、FeCl2 ·4H2O及NiCl2·6H2O投加量对餐厨垃圾厌氧消化总固体(TS)、挥发性固体(VS)和COD减量及累积产气量的影响,确定了三因素的主次顺序及最优工艺条件.结果表明,当CoCl2·6H2O、FeCl2·4H2O及NiCl2·6H2O的投加量分别为0.1 mg/(L·d)、1 mg/(L·d)和0.4 mg/(L·d)时,餐厨垃圾厌氧消化减量及产气效果均最优.在此条件下,经过25 d单相厌氧消化,餐厨垃圾厌氧消化TS、VS、COD的去除率及累积产气量分别达到46.04%、61.02%、58.24%和27 433 mL/L,比不投加微量金属的处理分别高16.98%、28.12%、27.84%和48.63%.Co、Fe和Ni的投加量对餐厨垃圾厌氧消化TS、VS和COD去除率及累积产气量均有显著影响,其中Co的影响达到极显著水平;Co、Fe和Ni对餐厨垃圾厌氧消化减量及产气效率影响的主次顺序及显著性从大到小均为Co、Ni、Fe. 相似文献
259.
以餐厨垃圾为研究对象,在高温(55±1)℃条件下,采用连续湿式厌氧发酵技术研究发酵过程中进料有机负荷、日产气量、pH值、挥发性有机酸(VFA)质量浓度等参数的变化情况及相互作用关系.结果表明:厌氧消化过程中出现了4个阶段,即适应阶段、提高阶段、稳定阶段和超负荷阶段;反应达到稳定阶段时,反应器运行有机负荷为3.9 kg/(m3·d),系统pH值稳定在7.8左右,平均产气速率达到5.26L/d;负荷达到4.2 kg/(m3·d)时,对系统产生明显抑制作用. 相似文献
260.
Daniela A. Guitart Catherine M. Pickering 《Journal of Environmental Planning and Management》2015,58(2):189-212
While claims about the environmental benefits of community gardens abound, few researchers have systematically assessed the ecological integrity of gardening practices. This study investigated gardening practices in 50 community gardens in Brisbane and Gold Coast cities, Australia. The study aimed to better understand how gardening practices might affect the ecological viability of community gardens. Factors investigated included: garden bio-physical characteristics, operators’ motivations, gardeners’ socio-demographic backgrounds, garden facilities and types of plants grown. Two broad types of gardens were identified: permaculture (21 gardens) and non-permaculture (29 gardens). Permaculture gardens used lower-impact gardening practices. Findings have policy implications for environmental planning and management. 相似文献