全文获取类型
收费全文 | 64篇 |
免费 | 0篇 |
专业分类
安全科学 | 8篇 |
环保管理 | 14篇 |
综合类 | 3篇 |
基础理论 | 13篇 |
污染及防治 | 15篇 |
评价与监测 | 6篇 |
社会与环境 | 4篇 |
灾害及防治 | 1篇 |
出版年
2018年 | 1篇 |
2017年 | 1篇 |
2016年 | 1篇 |
2015年 | 1篇 |
2014年 | 2篇 |
2013年 | 4篇 |
2011年 | 2篇 |
2010年 | 2篇 |
2009年 | 7篇 |
2008年 | 5篇 |
2007年 | 4篇 |
2006年 | 2篇 |
2005年 | 1篇 |
2003年 | 2篇 |
2002年 | 1篇 |
2001年 | 2篇 |
2000年 | 3篇 |
1999年 | 3篇 |
1997年 | 1篇 |
1996年 | 1篇 |
1995年 | 1篇 |
1994年 | 2篇 |
1993年 | 1篇 |
1990年 | 2篇 |
1989年 | 1篇 |
1984年 | 1篇 |
1983年 | 1篇 |
1982年 | 3篇 |
1981年 | 1篇 |
1980年 | 2篇 |
1978年 | 1篇 |
1973年 | 1篇 |
1970年 | 1篇 |
排序方式: 共有64条查询结果,搜索用时 312 毫秒
21.
Burger J Gochfeld M Jeitner C Gray M Shukla T Shukla S Burke S 《Environmental monitoring and assessment》2007,128(1-3):311-321
Kelp may be useful as a bioindicator because they are primary producers that are eaten by higher trophic level organisms,
including people and livestock. Often when kelp or other algae species are used as bioindicators, the whole organism is homogenized.
However, some kelp can be over 25 m long from their holdfast to the tip of the blade, making it important to understand how
contaminant levels vary throughout the plant. We compared the levels of arsenic, cadmium, chromium, lead, manganese, mercury
and selenium in five different parts of the kelp Alaria nana to examine the variability of metal distribution. To be useful as a bioindicator, it is critical to know whether levels are
constant throughout the kelp, or which part is the highest accumulator. Kelp were collected on Adak Island in the Aleutian
Chain of Alaska from the Adak Harbor and Clam Cove, which opens onto the Bering Sea. In addition to determining if the levels
differ in different parts of the kelp, we wanted to determine whether there were locational or size-related differences. Regression
models indicated that between 14% and 43% of the variation in the levels of arsenic, cadmium, chromium, manganese, mercury,
and selenium was explained by total length, part of the plant, and location (but not for lead). The main contributors to variability
were length (for arsenic and selenium), location (mercury), and part of the plant (for arsenic, cadmium, chromium and manganese).
The higher levels of selenium occurred at Clam Cove, while mercury was higher at the harbor. Where there was a significant
difference among parts, the holdfast had the highest levels, although the differences were not great. These data indicate
that consistency should be applied in selecting the part of kelp (and the length) to be used as a bioindicator. While any
part of Alaria could be collected for some metals, for arsenic, cadmium, chromium, and manganese a conversion should be made among parts.
In the Aleutians the holdfast can be perennial while the blade, whipped to pieces by winter wave action, is regrown each year.
Thus the holdfast may be used for longer-term exposure for arsenic, cadmium, chromium and manganese, while the blade can be
used for short-term exposure for all metals. Cadmium, lead and selenium were at levels that suggest that predators, including
people, may be at risk from consuming Alaria. More attention should be devoted to heavy metal levels in kelp and other algae from Adak, particularly where they may play
a role in a subsistence diets. 相似文献
22.
23.
Ronald J. Burke 《组织行为杂志》1993,14(5):459-472
The introduction of a national health care system in Canada has resulted in regular and increasing conflict between the medical profession, government and other political actors. The present study utilizes a stressor–strain framework to understand physician militancy in Canada. Data were collected from 2087 men and women physicians using questionnaires completed anonymously. Four groups of predictor variables identified in previous research were considered: individual demographic characteristics, practice characteristics, work stressors, and work and professional satisfactions. Empirical support for the model was found. Each panel of predictor variables had significant and unique relationships with measures of physician militancy. 相似文献
24.
The primary objective of this paper is to discuss the limitations of risk management as a strategy for Australian local government climate change adaptation and explore the advantages of complementary approaches, including a social-ecological resilience framework, adaptive and transition management, and vulnerability assessment. Some federal and local government initiatives addressing the limitations of risk-based approaches are introduced. We argue that conventional risk-based approaches to adaptation, largely focused on hazard identification and quantitative modelling, will be inadequate on their own for dealing with the challenges of climate change. We suggest that responses to climate change adaptation should move beyond conventional risk-based strategies to more realistically account for complex and dynamically evolving social-ecological systems. 相似文献
25.
Jacob J. Burke 《Natural resources forum》1994,18(3):181-192
In southern Africa institutional capacity in the water sector is severely limited by diminishing regular budget and external assistance allocations. The result has been an overall decline in operational water resource management. This is ironic given the international community's current concern with 'integrated' or 'comprehensive' water resources management. Often, so-called integrated attempts at river basin planning and development have been conceived within the framework of a river basin authority or regional master plans. Such large-scale attempts have not necessarily been compatible either with the national capacity in water resources management or the existing institutional and legislative frameworks. In many cases the actual integration of a basin's physical resources and social, economic and environmental demands is poorly executed. To examine a way forward in resolving what is clearly an unsustainable state of affairs, a diagnostic study of the Kafue Basin, Zambia, was carried out in order to identify a set of water resource management options for a basin currently under stress. A physical framework for the Kafue Basin was established and principal subcatchments and hydro-geological subsystems identified. Current water resource issues in the basin are discussed and a multiobjective approach is proposed to allow intersectoral competition for the basin's limited water resources to be reconciled. 相似文献
26.
M. Abdalla M. Jones J. Yeluripati P. Smith J. Burke M. Williams 《Atmospheric environment (Oxford, England : 1994)》2010,44(25):2961-2970
Simulation models are one of the approaches used to investigate greenhouse gas emissions and potential effects of global warming on terrestrial ecosystems. DayCent which is the daily time-step version of the CENTURY biogeochemical model, and DNDC (the DeNitrification–DeComposition model) were tested against observed nitrous oxide flux data from a field experiment on cut and extensively grazed pasture located at the Teagasc Oak Park Research Centre, Co. Carlow, Ireland. The soil was classified as a free draining sandy clay loam soil with a pH of 7.3 and a mean organic carbon and nitrogen content at 0–20 cm of 38 and 4.4 g kg?1 dry soil, respectively. The aims of this study were to validate DayCent and DNDC models for estimating N2O emissions from fertilized humid pasture, and to investigate the impacts of future climate change on N2O fluxes and biomass production. Measurements of N2O flux were carried out from November 2003 to November 2004 using static chambers. Three climate scenarios, a baseline of measured climatic data from the weather station at Carlow, and high and low temperature sensitivity scenarios predicted by the Community Climate Change Consortium For Ireland (C4I) based on the Hadley Centre Global Climate Model (HadCM3) and the Intergovernment Panel on Climate Change (IPCC) A1B emission scenario were investigated. DayCent predicted cumulative N2O flux and biomass production under fertilized grass with relative deviations of +38% and (?23%) from the measured, respectively. However, DayCent performs poorly under the control plots, with flux relative deviation of (?57%) from the measured. Comparison between simulated and measured flux suggests that both DayCent model’s response to N fertilizer and simulated background flux need to be adjusted. DNDC overestimated the measured flux with relative deviations of +132 and +258% due to overestimation of the effects of SOC. DayCent, though requiring some calibration for Irish conditions, simulated N2O fluxes more consistently than did DNDC. We used DayCent to estimate future fluxes of N2O from this field. No significant differences were found between cumulative N2O flux under climate change and baseline conditions. However, above-ground grass biomass was significantly increased from the baseline of 33 t ha?1 to 45 (+34%) and 50 (+48%) t dry matter ha?1 for the low and high temperature sensitivity scenario respectively. The increase in above-ground grass biomass was mainly due to the overall effects of high precipitation, temperature and CO2 concentration. Our results indicate that because of high N demand by the vigorously growing grass, cumulative N2O flux is not projected to increase significantly under climate change, unless more N is applied. This was observed for both the high and low temperature sensitivity scenarios. 相似文献
27.
Cynthia Howard-Reed Anne W. Rea Maria J. Zufall Janet M. Burke Ron W. Williams Jack C. Suggs 《Journal of the Air & Waste Management Association (1995)》2013,63(7):1125-1132
ABSTRACT In population exposure studies, personal exposure to PM is typically measured as a 12- to 24-hr integrated mass concentration. To better understand short-term variation in personal PM exposure, continuous (1-min averaging time) nephelometers were worn by 15 participants as part of two U.S. Environmental Protection Agency (EPA) longitudinal PM exposure studies conducted in Baltimore County, MD, and Fresno, CA. Participants also wore iner-tial impactor samplers (24-hr integrated filter samples) and recorded their daily activities in 15-min intervals. In Baltimore, the nephelometers correlated well (R2 = 0.66) with the PM25 impactors. Time-series plots of personal nephelometer data showed each participant's PM exposure to consist of a series of peaks of relatively short duration. Activities corresponding to a significant instrument response included cooking, outdoor activities, transportation, laundry, cleaning, shopping, gardening, moving between microenvironments, and removing/putting on the instrument. On average, 63-66% of the daily PM exposure occurred indoors at home (about 2/3 of which occurred during waking hours), primarily due to the large amount of time spent in that location (an average of 7277%). Although not a reference method for measuring mass concentration, the nephelometer did help identify PM sources and the relative contribution of those sources to an individual's personal exposure. 相似文献
28.
Katherine Shields Andrew Fischer Chris Burke 《Journal of Environmental Planning and Management》2015,58(7):1270-1290
Discharge from the Great Barrier Reef Catchment (GBRC) is considered the second most serious threat to the Great Barrier Reef, Australia. Utilising principal component analysis (PCA) and cluster analysis (CA), this research aimed to assess the variability and co-variation of 28 water basins (WBs) within the GBRC, in order to improve the institutional arrangements and regulation of water quality and increase collaboration horizontally between management organisations, and vertically between government tiers. Water basin variability was measured by nine variables: size (ha), population, agricultural land use (ha), number of major water storages, major rivers and major towns, total nitrogen exported (T/yr), total phosphorus exported (T/yr) and herbicide use (ha). The Fitzroy WB, with PC scores of 7.0081, 2.2897 and ?1.6504, was identified as the most dissimilar and therefore needing to be managed differently. Many WBs within the same regions were very dissimilar to each other, indicating that current management practices, based largely on geographic location, are unlikely to be the most efficient and effective. Instead, managing groups of WBs with similar geo-political properties (determined by the CA) could be more effective and efficient. Coordination and collaboration are key to successful ecosystem based management, therefore managing similar WBs together through inter-NRM (natural resource management) agreements, irrespective of their geographical location, facilitates management bodies building strong, cooperative working relationships. 相似文献
29.
Howard-Reed C Rea AW Zufall MJ Burke JM Williams RW Suggs JC Sheldon LS Walsh D Kwok R 《Journal of the Air & Waste Management Association (1995)》2000,50(7):1125-1132
In population exposure studies, personal exposure to PM is typically measured as a 12- to 24-hr integrated mass concentration. To better understand short-term variation in personal PM exposure, continuous (1-min averaging time) nephelometers were worn by 15 participants as part of two U.S. Environmental Protection Agency (EPA) longitudinal PM exposure studies conducted in Baltimore County, MD, and Fresno, CA. Participants also wore inertial impactor samplers (24-hr integrated filter samples) and recorded their daily activities in 15-min intervals. In Baltimore, the nephelometers correlated well (R2 = 0.66) with the PM2.5 impactors. Time-series plots of personal nephelometer data showed each participant's PM exposure to consist of a series of peaks of relatively short duration. Activities corresponding to a significant instrument response included cooking, outdoor activities, transportation, laundry, cleaning, shopping, gardening, moving between microenvironments, and removing/putting on the instrument. On average, 63-66% of the daily PM exposure occurred indoors at home (about 2/3 of which occurred during waking hours), primarily due to the large amount of time spent in that location (an average of 72-77%). Although not a reference method for measuring mass concentration, the nephelometer did help identify PM sources and the relative contribution of those sources to an individual's personal exposure. 相似文献
30.