全文获取类型
收费全文 | 109篇 |
免费 | 2篇 |
国内免费 | 1篇 |
专业分类
安全科学 | 4篇 |
废物处理 | 5篇 |
环保管理 | 25篇 |
综合类 | 7篇 |
基础理论 | 37篇 |
环境理论 | 1篇 |
污染及防治 | 20篇 |
评价与监测 | 3篇 |
社会与环境 | 8篇 |
灾害及防治 | 2篇 |
出版年
2023年 | 1篇 |
2022年 | 3篇 |
2021年 | 3篇 |
2020年 | 1篇 |
2019年 | 3篇 |
2018年 | 8篇 |
2017年 | 8篇 |
2016年 | 3篇 |
2015年 | 4篇 |
2014年 | 6篇 |
2013年 | 6篇 |
2012年 | 5篇 |
2011年 | 10篇 |
2010年 | 5篇 |
2009年 | 7篇 |
2008年 | 6篇 |
2007年 | 5篇 |
2006年 | 3篇 |
2005年 | 3篇 |
2004年 | 3篇 |
2003年 | 2篇 |
2002年 | 1篇 |
2001年 | 1篇 |
2000年 | 3篇 |
1999年 | 3篇 |
1997年 | 1篇 |
1995年 | 1篇 |
1992年 | 1篇 |
1990年 | 2篇 |
1984年 | 1篇 |
1979年 | 1篇 |
1977年 | 1篇 |
1974年 | 1篇 |
排序方式: 共有112条查询结果,搜索用时 15 毫秒
71.
Stanislaw Lozecznik Richard Sparling Jan A. Oleszkiewicz Shawn Clark Jamie F. VanGulck 《Waste management (New York, N.Y.)》2010,30(11):2030-2036
In this study, an anaerobic sequencing batch reactor (ASBR) was operated with leachate from Brady Road Municipal Landfill in Winnipeg, Manitoba, Canada. Leachate was collected twice from the same cell at the landfill, during the first and 70th day of the study, and then fed into the ASBR. The ASBR was seeded at the start-up with biosolids from the anaerobic digester from Winnipeg’s North End Water Pollution Control Center (NEWPCC). Due to the higher COD and VFA removal rates measured with the second batch of leachate, an increase of approximately 0.3 pH units was observed during each cycle (from pH 7.2 to 7.5). In addition, CO2 was produced between cycles at constant temperature where a fraction of the CO2 became dissolved, shifting the CO2/bicarbonate/carbonate equilibrium. Concurrent with the increase in pH and carbonate, an accumulation of fixed suspend solids (FSS) was observed within the ASBR, indicating a buildup of inorganic material over time. From it, Ca2+ and Mg2+ were measured within the reactor on day 140, indicating that most of the dissolved Ca2+ was removed within cycles. There is precedence from past researches of clogging in leachate-collection systems (Rowe et al., 2004) that changes in pH and carbonate content combined with high concentrations of metals such as Ca2+ and Mg2+ result in carbonate mineral precipitants. A parallel study investigated this observation, indicating that leachate with high concentration of Ca2+ under CO2 saturation conditions can precipitate out CaCO3 at the pH values obtained between digestion cycles. These studies presented show that methanogenesis of leachate impacts the removal of organic (COD, VFA) as well as inorganic (FSS, Ca2+) clog constituents from the leachate, that otherwise will accumulate inside of the recirculation pipe in bioreactor landfills. In addition, a robust methanogenesis of leachate was achieved, averaging rates of 0.35 L CH4 produced/g COD removed which is similar to the theoretical removal of 0.4 L CH4/g COD. Therefore, using methanogenesis of leachate prior to recirculation in bioreactor landfills will help to (1) control clog formation within leachate pipes and (2) produce an important additional source of energy on-site. 相似文献
72.
Gaiser BK Biswas A Rosenkranz P Jepson MA Lead JR Stone V Tyler CR Fernandes TF 《Journal of environmental monitoring : JEM》2011,13(5):1227-1235
Acute (96 h) and chronic (21 d) exposures of Daphnia magna neonates were carried out with nano- and micro-sized Ag and CeO(2) particles to assess the influence of both material and size of particles on mortality and moulting. Mortality rates for silver in the acute exposures were: AgNP, 56.7 ± 23.3% at 0.1 mg L(-1) and 100 ± 20% at 1 mg L(-1), and micro-Ag, 13.3 ± 6.7% at 0.1 mg L(-1) and 80 ± 20% at 1 mg L(-1). CeO(2) was not acutely toxic at concentrations up to 10 mg L(-1). Mortality for Ag over 21d at concentrations of up to 0.05 mg L(-1) was low, while mortality of 30% was observed for 0.001 mg L(-1) of nano-Ag. CeO(2), with the exception of the 10 mg L(-1) of nano-CeO(2) (100% mortality by day 7), was non-toxic. Inhibition of moulting and growth in the acute study occurred at toxic concentrations (Ag particles), and at 10 mg L(-1) of nano-CeO(2). The chronic study revealed reduced moulting at 0.001 mg L(-1) of nano-Ag and 0.01 and 0.05 mg L(-1) of both sizes of Ag, but there was no impact on D. magna size, and no effects of CeO(2). The toxicity of nano-CeO(2) may be attributed to reduced feeding and physical interference with the daphnids' carapace, resulting in reduced swimming ability. Our results suggest that Ag NPs in particular have the potential to be harmful to aquatic invertebrates after release into the environment, whereas CeO(2) particles appear to cause little adverse effects, and only at environmentally irrelevant concentrations. 相似文献
73.
Evaluating the efficacy of adaptive management approaches: Is there a formula for success? 总被引:1,自引:0,他引:1
Within the field of natural-resources management, the application of adaptive management is appropriate for complex problems high in uncertainty. Adaptive management is becoming an increasingly popular management-decision tool within the scientific community and has developed into two primary schools of thought: the Resilience-Experimentalist School (with high emphasis on stakeholder involvement, resilience, and highly complex models) and the Decision-Theoretic School (which results in relatively simple models through emphasizing stakeholder involvement for identifying management objectives). Because of these differences, adaptive management plans implemented under each of these schools may yield varying levels of success. We evaluated peer-reviewed literature focused on incorporation of adaptive management to identify components of successful adaptive management plans. Our evaluation included adaptive management elements such as stakeholder involvement, definitions of management objectives and actions, use and complexity of predictive models, and the sequence in which these elements were applied. We also defined a scale of degrees of success to make comparisons between the two adaptive management schools of thought. Our results include the relationship between the adaptive management process documented in the reviewed literature and our defined continuum of successful outcomes. Our data suggest an increase in the number of published articles with substantive discussion of adaptive management from 2000 to 2009 at a mean rate of annual change of 0.92 (r2 = 0.56). Additionally, our examination of data for temporal patterns related to each school resulted in an increase in acknowledgement of the Decision-Theoretic School of thought at a mean annual rate of change of 0.02 (r2 = 0.6679) and a stable acknowledgement for the Resilience-Experimentalist School of thought (r2 = 0.0042; slope = 0.0013). Identifying the elements of successful adaptive management will be advantageous to natural-resources managers considering adaptive management as a decision tool. 相似文献
74.
Nicholas K. Dulvy ‡ Julian D. Metcalfe † Jamie Glanville Mike G. Pawson † and John D. Reynolds 《Conservation biology》2000,14(1):283-293
Abstract: Skates are arguably the most vulnerable of exploited marine fishes. Their vulnerability is often assessed by examining fisheries catch trends, but these data are not generally recorded on a species basis except in France. Aggregated skate catch statistics tend to exhibit more stable trends than those of other elasmobranch fisheries. We tested whether such apparent stability in aggregated catch trends could mask population declines of individual species. We examined two time series of species-specific surveys of a relatively stable skate fishery in the northeast Atlantic. These surveys revealed the disappearance of two skate species, long-nose skate ( Dipturus oxyrhinchus ) and white skate ( Rostroraja alba ) and confirmed a previously documented decline of the common skate ( D. batis ). Of the remaining five skate species, the three larger ones have declined, whereas two smaller species have increased in abundance. The increase in abundance and biomass of the smaller species has resulted in the stability of the aggregated catch trends. Because there is significant dietary overlap among species, we suggest the increase in abundance of the smaller species may be due to competitive release as the larger species declined. A consequence of this kind of stability is that declining species cannot be detected without species-specific data, especially in taxa exhibiting competitive interactions. This may explain why previously documented disappearances of two species of skates went unnoticed for so long. The conservation of skates and other elasmobranchs requires species-specific monitoring and special attention to larger species. 相似文献
75.
76.
E. Jamie Trammell J. Scott Thomas Dave Mouat Quinn Korbulic Scott Bassett 《Journal of Environmental Planning and Management》2018,61(1):64-85
Scenario planning is an effective approach for examining possible futures by exploring the implications and consequences of different policy responses to landscape stressors. We present here a case study that explores plausible futures of urban growth in Southern Nevada, USA that illustrates how scenario analysis can be used to inform region-wide resource management by spatially modeling drivers of change, resource impacts, and potential policy responses. Using a suite of energy, water and biodiversity impact models, we assess the outcomes of the various futures on priority resources, resulting in a clear basis of comparison between alternative policies and their potential outcomes. This case study demonstrates the utility of scenario modeling for natural resource management by exploring crucial policy decisions that might be made in the near-term that could have lasting and sometimes conflicting influences on regional resources over the long term. 相似文献
77.
Joseph P. Herring Richard C. Schultz Thomas M. Isenhart 《Journal of the American Water Resources Association》2006,42(1):145-155
An observational study was conducted at the watershed scale using land cover (vegetation) data to assess the absence or presence of riparian buffers in three northeastern Missouri watersheds. Forests and grasslands lying within a 61 m (200 ft) parallel band directly adjacent to streams were considered “buffers” for improving or protecting water quality and were characterized according to their length, width, and vegetation type. Results indicated that riparian buffers were abundant throughout the watersheds but were typically narrow along first‐order and second‐order streams; in many cases they may not have been wide enough to provide adequate stream protection. At least 90 percent of all streams had buffer vegetation immediately adjacent to the streambanks, but as few as 31 percent of first‐order streams had buffers extending to 61 m from the stream on at least one side. On‐site evaluations are needed to determine the condition of these forests and grasslands and their ability to process nonpoint source pollutants. The results will be useful for providing natural resource managers with knowledge of current watershed conditions as well as in identifying specific locations for future conservation efforts within each watershed. 相似文献
78.
Sam Lapp Tianhao Wu Corinne Richards-Zawacki Jamie Voyles Keely Michelle Rodriguez Hila Shamon Justin Kitzes 《Conservation biology》2021,35(5):1659-1668
Anurans (frogs and toads) are among the most globally threatened taxonomic groups. Successful conservation of anurans will rely on improved data on the status and changes in local populations, particularly for rare and threatened species. Automated sensors, such as acoustic recorders, have the potential to provide such data by massively increasing the spatial and temporal scale of population sampling efforts. Analyzing such data sets will require robust and efficient tools that can automatically identify the presence of a species in audio recordings. Like bats and birds, many anuran species produce distinct vocalizations that can be captured by autonomous acoustic recorders and represent excellent candidates for automated recognition. However, in contrast to birds and bats, effective automated acoustic recognition tools for anurans are not yet widely available. An effective automated call-recognition method for anurans must be robust to the challenges of real-world field data and should not require extensive labeled data sets. We devised a vocalization identification tool that classifies anuran vocalizations in audio recordings based on their periodic structure: the repeat interval-based bioacoustic identification tool (RIBBIT). We applied RIBBIT to field recordings to study the boreal chorus frog (Pseudacris maculata) of temperate North American grasslands and the critically endangered variable harlequin frog (Atelopus varius) of tropical Central American rainforests. The tool accurately identified boreal chorus frogs, even when they vocalized in heavily overlapping choruses and identified variable harlequin frog vocalizations at a field site where it had been very rarely encountered in visual surveys. Using a few simple parameters, RIBBIT can detect any vocalization with a periodic structure, including those of many anurans, insects, birds, and mammals. We provide open-source implementations of RIBBIT in Python and R to support its use for other taxa and communities. 相似文献
79.
Frederic Paik Schoenberg Jamie Pompa Chien-Hsun Chang 《Environmental and Ecological Statistics》2009,16(2):251-269
This paper explores the use of, and problems that arise in, kernel smoothing and parametric estimation of the relationships
between wildfire incidence and various meteorological variables. Such relationships may be treated as components in separable
point process models for wildfire activity. The resulting models can be used for comparative purposes in order to assess the
predictive performance of the Burning Index.
相似文献
Frederic Paik SchoenbergEmail: |
80.
Both cooperation and conflict between the sexes are commonplace in monogamous mating systems. However, little is known about
how cooperation and competition varies seasonally in monogamous species that maintain permanent territories. We presented
territorial pairs of male and female New Zealand robins (Petroica australis) with a large supply of insect prey at monthly intervals for 2 years. Behavioural observations after food presentation were
then made to quantify seasonal and sexual differences in aggressive interactions over prey, prey acquisition rates, mate provisioning,
offspring provisioning, selfish food hoarding and cache retrieval. Data were used to evaluate sex-specific behavioural strategies
of mediating competition for food. Results showed that males aggressively excluded females from experimental food sources
year-round. Females only accessed food sources when males left them unattended. Consequently, females acquired fewer prey
than males. After controlling for differences in prey acquisition, both sexes consumed similar amounts of prey in the non-breeding
season. Even though males aggressively excluded females from accessing food sources directly, males fed large amounts of prey
to females during the breeding season. Both sexes provisioned young at similar rates. Males cached less prey than females
in the breeding season but more prey than females in the non-breeding season. Females showed similar caching intensities year-round.
Although males tried to defend their hoards, females frequently retrieved male-made caches. Overall, results showed that although
New Zealand robins cooperate to raise offspring during the breeding season, conflict between the sexes occurs year-round.
Males and females display different behavioural strategies to gain access to experimental food sources, which appear to lessen
male–female competition for food and evenly distribute food resources between the sexes. 相似文献