全文获取类型
收费全文 | 33230篇 |
免费 | 349篇 |
国内免费 | 267篇 |
专业分类
安全科学 | 1085篇 |
废物处理 | 1626篇 |
环保管理 | 4242篇 |
综合类 | 5035篇 |
基础理论 | 8642篇 |
环境理论 | 9篇 |
污染及防治 | 8234篇 |
评价与监测 | 2366篇 |
社会与环境 | 2403篇 |
灾害及防治 | 204篇 |
出版年
2023年 | 168篇 |
2022年 | 307篇 |
2021年 | 351篇 |
2020年 | 207篇 |
2019年 | 263篇 |
2018年 | 480篇 |
2017年 | 504篇 |
2016年 | 786篇 |
2015年 | 568篇 |
2014年 | 931篇 |
2013年 | 2731篇 |
2012年 | 1117篇 |
2011年 | 1500篇 |
2010年 | 1234篇 |
2009年 | 1273篇 |
2008年 | 1564篇 |
2007年 | 1482篇 |
2006年 | 1375篇 |
2005年 | 1197篇 |
2004年 | 1146篇 |
2003年 | 1123篇 |
2002年 | 1034篇 |
2001年 | 1248篇 |
2000年 | 873篇 |
1999年 | 544篇 |
1998年 | 395篇 |
1997年 | 419篇 |
1996年 | 427篇 |
1995年 | 507篇 |
1994年 | 431篇 |
1993年 | 379篇 |
1992年 | 417篇 |
1991年 | 397篇 |
1990年 | 373篇 |
1989年 | 363篇 |
1988年 | 336篇 |
1987年 | 283篇 |
1986年 | 290篇 |
1985年 | 276篇 |
1984年 | 303篇 |
1983年 | 287篇 |
1982年 | 298篇 |
1981年 | 239篇 |
1980年 | 189篇 |
1979年 | 207篇 |
1978年 | 177篇 |
1977年 | 158篇 |
1974年 | 153篇 |
1973年 | 191篇 |
1972年 | 162篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
241.
Rosaleen Duffy Freya A. V. St John Bram Büscher Dan Brockington 《Conservation biology》2016,30(1):14-22
Conservation organizations have increasingly raised concerns about escalating rates of illegal hunting and trade in wildlife. Previous studies have concluded that people hunt illegally because they are financially poor or lack alternative livelihood strategies. However, there has been little attempt to develop a richer understanding of the motivations behind contemporary illegal wildlife hunting. As a first step, we reviewed the academic and policy literatures on poaching and illegal wildlife use and considered the meanings of poverty and the relative importance of structure and individual agency. We placed motivations for illegal wildlife hunting within the context of the complex history of how wildlife laws were initially designed and enforced to indicate how hunting practices by specific communities were criminalized. We also considered the nature of poverty and the reasons for economic deprivation in particular communities to indicate how particular understandings of poverty as material deprivation ultimately shape approaches to illegal wildlife hunting. We found there is a need for a much better understanding of what poverty is and what motivates people to hunt illegally. 相似文献
242.
243.
The Southern Ocean is one of the most rapidly changing ecosystems on the planet due to the effects of climate change and commercial fishing for ecologically important krill and fish. Because sea ice loss is expected to be accompanied by declines in krill and fish predators, decoupling the effects of climate and anthropogenic changes on these predator populations is crucial for ecosystem‐based management of the Southern Ocean. We reviewed research published from 2007 to 2014 that incorporated very high‐resolution satellite imagery to assess distribution, abundance, and effects of climate and other anthropogenic changes on populations of predators in polar regions. Very high‐resolution imagery has been used to study 7 species of polar animals in 13 papers, many of which provide methods through which further research can be conducted. Use of very high‐resolution imagery in the Southern Ocean can provide a broader understanding of climate and anthropogenic forces on populations and inform management and conservation recommendations. We recommend that conservation biologists continue to integrate high‐resolution remote sensing into broad‐scale biodiversity and population studies in remote areas, where it can provide much needed detail. Aplicaciones de Imágenes de Muy Alta Resolución en el Estudio y Conservación de Grandes Depredadores en el Océano Antártico 相似文献
244.
AYESHA I. T. TULLOCH VIVITSKAIA J. D. TULLOCH MEGAN C. EVANS MORENA MILLS 《Conservation biology》2014,28(6):1462-1473
Understanding the social dimensions of conservation opportunity is crucial for conservation planning in multiple‐use landscapes. However, factors that influence the feasibility of implementing conservation actions, such as the history of landscape management, and landholders’ willingness to engage are often difficult or time consuming to quantify and rarely incorporated into planning. We examined how conservation agencies could reduce costs of acquiring such data by developing predictive models of management feasibility parameterized with social and biophysical factors likely to influence landholders’ decisions to engage in management. To test the utility of our best‐supported model, we developed 4 alternative investment scenarios based on different input data for conservation planning: social data only; biological data only; potential conservation opportunity derived from modeled feasibility that incurs no social data collection costs; and existing conservation opportunity derived from feasibility data that incurred collection costs. Using spatially explicit information on biodiversity values, feasibility, and management costs, we prioritized locations in southwest Australia to control an invasive predator that is detrimental to both agriculture and natural ecosystems: the red fox (Vulpes vulpes). When social data collection costs were moderate to high, the most cost‐effective investment scenario resulted from a predictive model of feasibility. Combining empirical feasibility data with biological data was more cost‐effective for prioritizing management when social data collection costs were low (<4% of the total budget). Calls for more data to inform conservation planning should take into account the costs and benefits of collecting and using social data to ensure that limited funding for conservation is spent in the most cost‐efficient and effective manner. 相似文献
245.
246.
Jeremy R. Brammer Nicolas D. Brunet A. Cole Burton Alain Cuerrier Finn Danielsen Kanwaljeet Dewan Thora Martina Herrmann Micha V. Jackson Rod Kennett Guillaume Larocque Monica Mulrennan Arun Kumar Pratihast Marie Saint‐Arnaud Colin Scott Murray M. Humphries 《Conservation biology》2016,30(6):1277-1287
Many argue that monitoring conducted exclusively by scientists is insufficient to address ongoing environmental challenges. One solution entails the use of mobile digital devices in participatory monitoring (PM) programs. But how digital data entry affects programs with varying levels of stakeholder participation, from nonscientists collecting field data to nonscientists administering every step of a monitoring program, remains unclear. We reviewed the successes, in terms of management interventions and sustainability, of 107 monitoring programs described in the literature (hereafter programs) and compared these with case studies from our PM experiences in Australia, Canada, Ethiopia, Ghana, Greenland, and Vietnam (hereafter cases). Our literature review showed that participatory programs were less likely to use digital devices, and 2 of our 3 more participatory cases were also slow to adopt digital data entry. Programs that were participatory and used digital devices were more likely to report management actions, which was consistent with cases in Ethiopia, Greenland, and Australia. Programs engaging volunteers were more frequently reported as ongoing, but those involving digital data entry were less often sustained when data collectors were volunteers. For the Vietnamese and Canadian cases, sustainability was undermined by a mismatch in stakeholder objectives. In the Ghanaian case, complex field protocols diminished monitoring sustainability. Innovative technologies attract interest, but the foundation of effective participatory adaptive monitoring depends more on collaboratively defined questions, objectives, conceptual models, and monitoring approaches. When this foundation is built through effective partnerships, digital data entry can enable the collection of more data of higher quality. Without this foundation, or when implemented ineffectively or unnecessarily, digital data entry can be an additional expense that distracts from core monitoring objectives and undermines project sustainability. The appropriate role of digital data entry in PM likely depends more on the context in which it is used and less on the technology itself. 相似文献
247.
Packa Vlastimil Howell Todd Bostan Vadim Furdui Vasile I. 《Environmental science and pollution research international》2021,28(23):29498-29508
Environmental Science and Pollution Research - Trophic status in surface waters has been mostly monitored by measuring soluble reactive phosphorus (SRP) and total phosphorus (TP). Additional to... 相似文献
248.
Aioub Ahmed A. A. Zuo Yayun Li Yankai Qie Xingtao Zhang Xianxia Essmat Nariman Wu Wenjun Hu Zhaonong 《Environmental science and pollution research international》2021,28(5):5101-5115
Environmental Science and Pollution Research - Cypermethrin (CYP) is a toxic manmade chemical compound belonging to pyrethroid insecticides contaminating the environment. Plantago major (PM) has... 相似文献
249.
Malki Zohair Atlam El-Sayed Ewis Ashraf Dagnew Guesh Ghoneim Osama A. Mohamed Abdallah A. Abdel-Daim Mohamed M. Gad Ibrahim 《Environmental science and pollution research international》2021,28(30):40496-40506
Environmental Science and Pollution Research - COVID-19 was first discovered in Wuhan, China in December 2019. It is one of the worst pandemics in human history. Recent studies reported that... 相似文献
250.
Vicente Estela Domingos Alves Célia A. Martins Vânia Almeida Susana Marta Lazaridis Mihalis 《Environmental science and pollution research international》2021,28(46):65385-65398
Environmental Science and Pollution Research - Residential settings are of utmost importance for human exposure, as it is where people spend most of their time. Residential wood combustion is a... 相似文献