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981.
生态单元制图是通过对区域遥感信息的解译及与现场调查信息的叠合,得到可视性较强的生态信息图谱,是将景观生态学成果应用到城乡规划中的一条有效途径。生态单元制图如何与中国城乡规划编制相衔接,提供专业、可靠的基础性研究成果,是本文期待解决的主要问题。提出了将城市所有用地类型都作为研究对象的"本土化"和"城市化"的生态单元分类方法,完成了符合我国《城市用地分类与建设用地标准》的生态单元制图分类系统(9大类37小类)及其景观生态学指数分析;通过绿地率、建筑密度、乔木树冠覆盖度、植物物种丰富度等各单项指标进行分层及叠加综合评价制图,科学全面地识别不同用地的生态价值。认为可以通过提出诸如各类城市用地的附属绿地的面积、容积率高低、建筑退让范围、大乔木的保护措施等具体细致的规划要求,来保护及调整城市用地内部的绿地面积及植被丰富度、乔木的覆盖度等生态指标,确保重要的城镇自然系统在城市开发过程中不受冲击,以及如何实现我国城市绿地的"精明增长"等后续研究方向。 相似文献
982.
Margit van Wessel Ronald van Buuren Cees van Woerkum 《Journal of Environmental Planning and Management》2015,58(1):156-174
This paper is a case study of a team of Dutch water managers who saw that to achieve flexibility in planning they needed to engage with organisational control requirements. Rather than approaching flexibility normatively, as much planning literature does, this paper presents a case of flexibility empirically – as something actors negotiate through their strategising within planning practice, within their organisational context. The analysis shows the importance of approaching flexibility in planning as an intra-organisational issue, presents insights on the strategies actors employ in negotiating flexibility and control intra-organisationally, and points to the political nature of dynamics between flexibility and control. 相似文献
983.
Larry Larsen Terri Morrell Gretchen Schalge Meghan Gallione Joseph Bell Kip Petersen Frederick Steiner 《Environmental management》1991,15(4):549-563
This article is the third in a series prepared to explain the Teller County growth management planning process. Once it was
determined by local decision-makers that Teller County, Colorado, would pursue a policy of directed growth, concepts based
on this policy were developed. These concepts presented visions and options for the future. Landscape plans then were developed
for Teller County and the City of Woodland Park planning area so that these options could be visualized by local leaders and
the public. The landscape plans were used as part of the ongoing citizen involvement process to inform the public about the
options for growth management. To provide even more information, detailed designs were developed for specific areas in the
county. From the landscape plan, public involvement effort, and detailed designs, specific implementation measures were identified,
discussed, and adopted. These measures included guidelines for administration, so that county and city goals could be linked
to the actual day-to-day management of development proposals.
Paper 3 in a series of 3. 相似文献
984.
William Whipple 《Journal of the American Water Resources Association》1991,27(6):895-902
ABSTRACT: Water quality controls of storm water runoff and infiltration should be a major part of a nonpoint source control program. Although surface runoff and ground water controls are often approached separately, coordination between the two is essential. For practical reasons, a rather simplified technology-based approach appears to be desirable. Areas affected vary greatly as to their sensitivity to pollution; and the various classes of pollutant source vary greatly as to their potential harmfulness. In effect, a matrix approach appears best, in which both vulnerability of the area and harmfulness of the pollutant source would have weight in determining which level of best management practices (BMP) would be appropriate, whether standard, special, or complete prohibition of the type facility under given circumstances. 相似文献
985.
986.
James G. Titus 《Environmental management》1991,15(1):39-58
Climatologists generally expect an anthropogenic global warming that could raise sea level 30–150 cm in the next century and
more thereafter. One of the impacts would be the loss of coastal wetlands. Although the inundation of adjacent dryland would
enable new wetlands to form, much of this land is or will soon be developed. If developed areas are protected, wetlands will
be squeezed between an advancing sea and the land being protected, which has already happened in China and the Netherlands,
where people have built dikes for centuries.
Unlike those countries, the United States has enough land to accommodate the landward migration of wetlands; but governments
lack the funds to purchase all the coastal lowlands that might be inundated and the legal authority to prohibit their development.
We propose a third approach: allowing property owners to use coastal lowlands today as they choose, but setting up a legal
mechanism to ensure that the land is abandoned if and when sea level rises enough to inundate it. Although compensation may
be required, this approach would cost less than 1% as much as purchasing the land, and would be (1) economically efficient
by enabling real estate markets to incorporate expectations of future sea level rise; (2) constitutional by compensating property
owners; and (3) politically feasible by pleasing people who care about the long-term fate of the coastal environment without
disturbing people who either are unconcerned about the distant future or do not believe sea level will rise.
This article demonstrates that it would be irrational to delay policy formulation until sea level rise projections are more
precise. The cost will be small if we act now but great if we wait, and sea level is already rising along most coasts. The
US government should develop a strategy in the next three years.
The opinions expressed in this paper do not necessarily reflect the views of EPA and no official endorsement should be inferred. 相似文献
987.
O. W. R. Lucas 《Journal of Environmental Planning and Management》1983,26(2):98-104
The value placed by the public on the nation's rural landscapes is emphasised by vociferous criticism of insensitive, large‐scale afforestation. As forestry causes massive changes in the landscape in the short term, with results that last for decades, the opportunity provided to improve and conserve should be positively grasped. There is evidence that concensus exists over a considerable part of landscape and design, and this paper explores some of the major factors in landscape design which are consistently important in forest landscapes. 相似文献
988.
Policy windows are transitory opportunities during which the likelihood of adopting new policy or legislative proposals is
greater than usual. Accepted wisdom has held that natural disasters serve as focusing events that generate policy windows
in their wake. This paper highlights the need for a more circumscribed understanding of when and where policy windows occur
based on the experiences of three US regional planning organizations: a hand-picked commission of community leaders, a council
of governments, and a special-purpose substate organization. The first operated in the San Francisco Bay Area of California
following the Loma Prieta earthquake (October 1989), and the other two in South Carolina's Atlantic coastal plain after Hurricane
Hugo (September 1989). The analysis concludes that natural disasters did not transform the agenda or mission of these entities.
Policy windows were neither automatic outcomes of focusing events nor did they ensure the adoption of pertinent policy within
the organizations investigated. Several conditions are minimally necessary for using policy windows to bring about hazard
mitigation: comprehensive institutional conceptualization of hazards management, institutional strength and flexibility, and
well-placed, effective policy entrepreneurs. 相似文献
989.
将环境保护计划纳入国民经济和社会发展计划,这在我国尚属首次。本文从法律依据,指导原则、指标体系、编制方法,支持系统等方面,探讨环境保护年度汁划管理中的若干问题。 相似文献
990.