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721.
Text analysis tools for identification of emerging topics and research gaps in conservation science 总被引:1,自引:0,他引:1
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Martin J. Westgate Philip S. Barton Jennifer C. Pierson David B. Lindenmayer 《Conservation biology》2015,29(6):1606-1614
Keeping track of conceptual and methodological developments is a critical skill for research scientists, but this task is increasingly difficult due to the high rate of academic publication. As a crisis discipline, conservation science is particularly in need of tools that facilitate rapid yet insightful synthesis. We show how a common text‐mining method (latent Dirichlet allocation, or topic modeling) and statistical tests familiar to ecologists (cluster analysis, regression, and network analysis) can be used to investigate trends and identify potential research gaps in the scientific literature. We tested these methods on the literature on ecological surrogates and indicators. Analysis of topic popularity within this corpus showed a strong emphasis on monitoring and management of fragmented ecosystems, while analysis of research gaps suggested a greater role for genetic surrogates and indicators. Our results show that automated text analysis methods need to be used with care, but can provide information that is complementary to that given by systematic reviews and meta‐analyses, increasing scientists’ capacity for research synthesis. 相似文献
722.
Nathan H. Rahe Karl W.J. Williard Jon E. Schoonover 《Journal of the American Water Resources Association》2015,51(4):898-909
Ecosystem processes such as water infiltration and denitrification largely determine how riparian buffers function to protect surface water quality. Reclaimed mine areas offer a unique opportunity to study the restoration of riparian function without the confounding influence of past land use. Between 1980 and 2000 in southern Illinois, agricultural fields with forest buffers were established along three restored stream reaches in reclaimed mine land. Our research objective was to compare common indicators of soil quality (infiltration, soil C and N, bulk density, and soil moisture) between forest and cultivated riparian zones to determine if riparian function was being restored. Soil bulk density was significantly lower in the forest buffers compared to the agricultural fields. The forest buffers had greater soil total C, total N, and moisture levels than agricultural fields likely due to greater organic matter inputs. Soil total C and N levels in forest buffers were positively related to age of restoration, indicating soil quality is gradually being restored in the buffers. Restoration success of riparian buffers should not be estimated by the return of structure alone; it also includes reestablishment of functions such as nutrient cycling and water retention that largely determine water quality benefits. Watershed planning efforts can expect a lag time on the order of decades between riparian restoration activities and surface water quality improvement. 相似文献
723.
Patrick Mwendwa 《中国人口.资源与环境(英文版)》2012,10(4)
To determine the climate changes that are due to natural variability and those due to human activities is quite challenging, just like delineating the impacts. Moreover, it is equally difficult to asce... 相似文献
724.
通过对广元市生态市的建设现状、指导思想、奋斗目标、建设路径进行深入分析,提出建设生态强市的可行性措施,并从法制、组织、资金、技术方面提供保障。 相似文献
725.
P. Smith J. U. Smith U. Franko K. Kuka V. A. Romanenkov L. K. Shevtsova M. Wattenbach P. Gottschalk O. D. Sirotenko D. I. Rukhovich P. V. Koroleva I. A. Romanenko N. V. Lisovoi 《Regional Environmental Change》2007,7(2):105-119
Three soil carbon models (RothC, CANDY and the Model of Humus Balance) were used to estimate the impacts of climate change
on agricultural mineral soil carbon stocks in European Russia and the Ukraine using detailed spatial data on land-use, future
land-use, cropping patterns, agricultural management, climate and soil type. Scenarios of climate were derived from the Hadley
Centre climate Version 3 (HadCM3) model; future yields were determined using the Soil–Climate–Yield model, and land use was
determined from regional agricultural and economic data and a model of agricultural economics. The models suggest that optimal
management, which entails the replacement of row crops with other crops, and the use of extra years of grass in the rotation
could reduce Soil organic carbon (SOC) loss in the croplands of European Russia and the Ukraine by 30–44% compared to the
business-as-usual management. The environmentally sustainable management scenario (SUS), though applied for a limited area
within the total region, suggests that much of this optimisation could be realised without damaging profitability for farmers. 相似文献
726.
Pragam Rathore 《Journal of Cleaner Production》2011,19(15):1709-1722
727.
In recent years, there has been a boom in environmental assessment reports utilizing environmental indicators. Most of these
publications are based on the casual chain frameworks (e.g., Pressure–State–Response (PSR), Driving force–State–Response (DSR),
and Driving force–Pressure–State–Impact–Response (DPSIR)). These frameworks have made an important contribution by emphasising
the importance of causality. However, the reliance on simple uni-directional chains is at the same time not very conducive
to a good understanding of the complexity of the processes behind environmental indicators. This limits the usefulness of
these frameworks for environmental (impact) assessments. In this paper we propose an enhanced DPSIR (eDPSIR) framework for
environmental indicators that takes inter-relations of indicators into account by relying on the use of causal networks rather
than causal chains. It will be shown how the concept of causal networks can increase insight into the inter-relation of environmental
issues and associated indicators, can facilitate the identification of key indicators for particular kinds of questions, and
can provide a useful first step to the establishment of dose–response functions. Working with causal networks can contribute
to more appropriate environmental policies and better management decisions. 相似文献
728.
Giuseppe Siracusa Angela D. La Rosa Paolo Palma Emiliano La Mola 《Environment, Development and Sustainability》2008,10(6):845-855
The emergy analysis was used to evaluate the sustainability of a village which aims to be ecologically friendly. The choice
of focusing on the use of local resources including agriculture and farm goods, photovoltaic panels, renewable heating and
cooling systems, recycled water from constructed wetlands etc., aims to obtain a sustainable village. Indices and ratios based
on emergy flows have been calculated and used to evaluate the behaviour of the whole system. Their dependence upon the fraction
of renewable and non renewable inputs as well as locally available versus purchased inputs from outside is stressed. A new
index of sustainability (SI) is also applied to the case study.
Readers should send their comments on this paper to BhaskarNath@aol.com within 3 months of publication of this issue. 相似文献
729.
Steven J. Wright Evelyn Habit Sara Adlerstein Oscar Parra Jeremy D. Semrau 《Sustainability Science》2009,4(1):29-36
A course for upper division undergraduate students was developed in response to a request for a cross-disciplinary course
in environmental sustainability with an emphasis on an international issue. The topic selected for the course focused on the
energy needs for Chile and a proposal for five hydropower projects on the Baker and Pascua Rivers in the Patagonia area. Collaborations
between the University of Michigan (USA) and the University of Concepción (Chile) to develop the course led to a plan to offer
a parallel course at both universities, with the students of both courses participating in a site visit to Patagonia. The
courses were structured to enhance learning through interdisciplinary team-based activities. The courses were taught in a
seminar format, with invited lecturers to provide background information on technical, environmental, economic, social, and
political issues surrounding hydropower development in general and the proposed projects in particular. The students combined
this information with insights obtained during the site visit to prepare a variety of course products, notably an assessment
of the concerns of the various affected stakeholder groups. Assessment of the course outcomes is discussed. 相似文献
730.
Educational initiative of Osaka University in sustainability science: mobilizing science and technology towards sustainability 总被引:1,自引:1,他引:0
Michinori Uwasu Helmut Yabar Keishiro Hara Yoshiyuki Shimoda Tatsuyoshi Saijo 《Sustainability Science》2009,4(1):45-53
One of the most important and yet difficult challenges that modern societies face is how to mobilize science and technology
(S&T) to minimize the impact of human activities on the Earth’s life support systems. As the establishment of inter-disciplinary
education programs is necessary to design a unified vision towards understanding the complexity of human nature, the Research
Institute for Sustainability Science (RISS) launched a new program on sustainability science in April 2008. The program expects
to address the issue of how to use knowledge more effectively to understand the dynamic interactions between nature and human
society. This paper first offers an overview of international and Japanese initiatives on sustainability education in which
we highlight the uniqueness of the attempt by the Integrated Research System for Sustainability Science (IR3S). The paper
then introduces the RISS program for sustainability science, addressing the principles and curriculum design of the program.
The paper discusses the main problems and constraints faced when developing the program, such as institutional barriers in
building a curriculum and obtaining cooperation from faculty. To challenge these barriers and limitations, the RISS uses the
program as a platform to disseminate the idea of sustainability science across the university. This attempt helps us to obtain
the continuing cooperation necessary to improve and maintain the program.
相似文献
Michinori UwasuEmail: |