全文获取类型
收费全文 | 137篇 |
免费 | 5篇 |
专业分类
安全科学 | 7篇 |
废物处理 | 9篇 |
环保管理 | 51篇 |
综合类 | 11篇 |
基础理论 | 22篇 |
污染及防治 | 21篇 |
评价与监测 | 16篇 |
社会与环境 | 4篇 |
灾害及防治 | 1篇 |
出版年
2023年 | 1篇 |
2021年 | 2篇 |
2020年 | 2篇 |
2019年 | 1篇 |
2018年 | 2篇 |
2017年 | 1篇 |
2016年 | 8篇 |
2015年 | 5篇 |
2014年 | 5篇 |
2013年 | 15篇 |
2012年 | 3篇 |
2011年 | 6篇 |
2010年 | 2篇 |
2009年 | 5篇 |
2008年 | 2篇 |
2007年 | 3篇 |
2006年 | 6篇 |
2005年 | 7篇 |
2004年 | 6篇 |
2003年 | 3篇 |
2002年 | 6篇 |
2001年 | 3篇 |
2000年 | 4篇 |
1999年 | 2篇 |
1998年 | 3篇 |
1997年 | 6篇 |
1996年 | 7篇 |
1995年 | 3篇 |
1994年 | 4篇 |
1993年 | 2篇 |
1992年 | 1篇 |
1990年 | 1篇 |
1989年 | 1篇 |
1988年 | 1篇 |
1986年 | 2篇 |
1984年 | 1篇 |
1983年 | 1篇 |
1982年 | 1篇 |
1979年 | 3篇 |
1978年 | 1篇 |
1972年 | 2篇 |
1971年 | 1篇 |
1959年 | 1篇 |
排序方式: 共有142条查询结果,搜索用时 15 毫秒
51.
Brad Gilmour Ted Huffman Andy Terauds Charles Jefferson 《Journal of Agricultural and Environmental Ethics》1996,9(1):16-41
The specific issue addressed in this paper is urban encroachment on agricultural lands, and the problems it poses for both analysis and the conservation of the land resource. The purpose of our discussion is two-fold: (1) to identify where and why traditional analytical and regulatory approaches fail to resolve land use conflicts, and (2) to explore ways and means of resolving some of the dilemmas which society faces in making land use decisions. This paper's contribution is in the spirit of Getting Incentives Right for the inter-temporal transfer of wealth, as represented in trade-offs between environmental and resource endowments and human and physical capital. Efforts are placed on identifying what the appropriate price, levy, taxes, and grant ratios ought to be in order to encourage individuals in the marketplace to act in society's interest. We have also explored ways of efficiently transmitting those incentives through the market mechanism, without unduly relying on bureaucratic methods or suasion. Emphasis is placed on mechanisms that have little scope for preferential access and are subject to public scrutiny; emphasis on such self-disciplining approaches should result in less effort expended on (unproductive) lobbying activities and bureaucratic administration.Brad Gilmour and Ted Huffman are Policy Analyst and Land Use Specialist respectively with Agriculture and Agri-food Canada. Andy Terauds and Charlie Jefferson are chairman and secretary respectively for the Ontario Institute of Agrologists Ottawa Branch Land Use Committee. This paper is intended to provoke thought and stimulate debate for input into the land use policy process and should not be seen as representing the views and policies of either Agriculture Canada or the Ontario Institute of Agrologists. 相似文献
52.
Mate choice experiments have generally focused on female choice; few have considered that males can also be selective. We
examined courtship in male field crickets sequentially introduced to four females of differing size. Large (L) and small (S)
females were introduced in order of either LSLS or SLSL. We demonstrate that naive males invest equally (courtship effort)
in the first female they meet, regardless of her size, but show greater courtship effort when they subsequently encounter
large compared with small females. Moreover, we demonstrate that males show this discriminatory behavior when they are permitted
to mate with females (i.e. use a spermatophore) but are less choosy when the female is removed before spermatophore transfer. 相似文献
53.
Beth A. Pletcher Maureen M. Sanz Jerrold S. Schlessel Suphat Kunaporn Carrie McKenna Martin G. Bialer M. Lita Alonso Ann-Leslie Zaslav W. Ted Brown James H. Ray 《黑龙江环境通报》1994,14(10):933-940
Two phenotypically abnormal liveborns in whom trisomy 16 mosaicism was diagnosed prenatally by amniocentesis are described. Analysis of a percutaneous umbilical blood sample in one case revealed a normal chromosomal complement. Ultrasound examinations performed at the time of amniocentesis were normal. Serial sonography during the late second and third trimesters demonstrated progressive intrauterine growth retardation (IUGR) in both fetuses and a cardiac defect in one. At birth, both infants had dysmorphic features and multiple congenital anomalies. Trisomy 16 mosaicism was confirmed postnatally in both infants in skin fibroblasts; however, peripheral blood samples contained only chromosomally normal cells. The two mosaic trisomy 16 cases described in this report, together with the five confirmed cases reported previously, demonstrate the need for caution in the counselling of patients when trisomy 16 mosaicism is diagnosed prenatally in amniotic fluid samples. Such cases potentially can result in the birth of dysmorphic infants with significant birth defects, growth retardation, and possible developmental disabilities. 相似文献
54.
Schweiger EW Bolgrien DW Angradi TR Kelly JR 《Environmental monitoring and assessment》2005,103(1-3):21-40
Most Great River ecosystems (GREs) are extensively modified and are not receiving adequate protection to prevent further habitat
degradation and loss of biotic integrity. In the United States, ecological monitoring and assessment of GREs has lagged behind
streams and estuaries, and the management of GREs is hampered by the lack of unbiased data at appropriate spatial scales.
Properties of GREs that make them challenging to monitor and assess include difficult sample logistics and high habitat diversity.
The U.S. Environmental Protection Agency’s Environmental Monitoring and Assessment Program (EMAP) has developed a comprehensive,
regional-scale, survey-based monitoring approach to assessment of streams and estuaries, but has not yet conducted research
on applying these tools to GRE monitoring. In this paper we present an overview of an EMAP research project on the Upper Missouri
River (UMR). We summarize the assessment objectives for the study, the design for selecting sample locations, the indicators
measured at these sites and the tools used to analyze data. We present an example of the type of statements that can be made
with EMAP monitoring data. With modification, the set of methodologies developed by EMAP may be well suited for assessment
of GREs in general. 相似文献
55.
The (109)Cd K-shell X-ray fluorescence (XRF) technique was used to measure in vivo tibia lead concentrations of 34 young adults living in the state of Vermont (USA) and the province of New Brunswick (Canada). The subjects ranged in age from 18 to 35 years, and had no known history of elevated lead exposure. Measurement parameters were varied, using the same XRF system for both populations. Tibia lead concentrations were low for both groups, with mean values of 0.7 microg lead g(-1) bone mineral (Vermont) and 0.5 microg g(-1)(New Brunswick). No individual measurement exceeded 7 microg g(-1). Mean uncertainty values obtained for the Vermont and New Brunswick subjects were 4.1 microg g(-1) and 2.6 microg g(-1), respectively. Improved measurement uncertainty in the New Brunswick group was attributed to the use of a reduced source-to-skin distance (approximately 5 mm) and a longer measurement time (3600 seconds) using a weaker radioisotope source (< or =0.42 GBq). Measurement uncertainty tended to increase with body mass index. For a given body mass index, female subjects returned a measurement uncertainty approximately 1 microg g(-1) greater than males. 相似文献
56.
Assessing the effectiveness of specially protected areas for conservation of Antarctica's botanical diversity 下载免费PDF全文
Vegetation is sparsely distributed over Antarctica's ice‐free ground, and distinct plant communities are present in each of the continent's 15 recently identified Antarctic Conservation Biogeographic Regions (ACBRs). With rapidly increasing human activity in Antarctica, terrestrial plant communities are at risk of damage or destruction by trampling, overland transport, and infrastructure construction and from the impacts of anthropogenically introduced species, as well as uncontrollable pressures such as fur seal (Arctocephalus gazella) activity and climate change. Under the Protocol on Environmental Protection to the Antarctic Treaty, the conservation of plant communities can be enacted and facilitated through the designation of Antarctic Specially Protected Areas (ASPAs). We examined the distribution within the 15 ACBRs of the 33 ASPAs whose explicit purpose includes protecting macroscopic terrestrial flora. We completed the first survey using normalized difference vegetation index (NDVI) satellite remote sensing to provide baseline data on the extent of vegetation cover in all ASPAs designated for plant protection in Antarctica. Large omissions in the protection of Antarctic botanical diversity were found. There was no protection of plant communities in 6 ACBRs, and in another 6, <0.4% of the ACBR area was included in an ASPA that protected vegetation. Protected vegetation cover within the 33 ASPAs totaled 16.1 km2 for the entire Antarctic continent; over half was within a single protected area. Over 96% of the protected vegetation was contained in 2 ACBRs, which together contributed only 7.8% of the continent's ice‐free ground. We conclude that Antarctic botanical diversity is clearly inadequately protected and call for systematic designation of ASPAs protecting plant communities by the Antarctic Treaty Consultative Parties, the members of the governing body of the continent. 相似文献
57.
58.
59.
Robert B. Fleming Kennith E. Foster 《Journal of the American Water Resources Association》1979,15(1):198-205
ABSTRACT: Western state water resources are drawing increasing attention because of prolonged drought, pound-water overdraft and an ever-increasing awareness of insufficient Colorado River water to supply a growing population and meet industrial demand. Arizona is no exception, and the alarming decline in ground-water levels has prompted the Arizona State Legislature to adopt legislation establishing the Ground-Water Management Study Commission to recommend legislative action by 1979. This paper summarizes Arizona's ground water legislative history and discusses possible alternatives for change. The authors address specific issues facing the State and offer a set of possible Commission recommendations. 相似文献
60.
Ted L. Napier Michael V. Carter Elizabeth G. Bryant 《Journal of the American Water Resources Association》1982,18(2):211-237
ABSTRACT: The purpose of this paper is to examine the correlates of attitudes toward alternative uses which could have been made of public resources employed to construct a multipurpose reservoir. A sample of 303 adult residents of a rural community impacted by lake construction was asked to evaluate several alternative development options which could have been implemented in lieu of the lake project. The alternative options evaluated were: rural industrialization, keeping land in agriculture and forests, improving public services, building a state or national park, drilling water wells for urban water supply, aid to small business, helping poor people, building several smaller impoundments, and private recreation development. The findings revealed the local people preferred the lake project to every option except keeping the land in agriculture and forest. Even this option was not strongly supported when compared with the lake project. Socio-demographic, attitude, and cost assessment factors were investigated using a “vested interest” perspective for hypotheses development. These findings demonstrated that costs and benefits were relatively good predictors of attitudes toward alternative development options and were supportive of the theoretical perspective advanced in this paper. 相似文献