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121.
A paired watershed study consisting of agroforestry (trees plus grass buffer strips), contour strips (grass buffer strips), and control treatments with a corn (Zea mays L.)-soybean [Glycine max (L.) Merr.] rotation was used to examine treatment effects on runoff, sediment, and nutrient losses. During the (1991-1997) calibration and subsequent three-year treatment periods, runoff was measured in 0.91- and 1.37-m H-flumes with bubbler flow meters. Composite samples were analyzed for sediment, total phosphorus (TP), total nitrogen (TN), nitrate, and ammonium. Calibration equations developed to predict runoff, sediment, and nutrients losses explained 66 to 97% of the variability between treatment watersheds. The contour strip and agroforestry treatments reduced runoff by 10 and 1% during the treatment period. In both treatments, most runoff reductions occurred in the second and third years after treatment establishment. The contour strip treatment reduced erosion by 19% in 1999, while erosion in the agroforestry treatment exceeded the predicted loss. Treatments reduced TP loss by 8 and 17% on contour strip and agroforestry watersheds. Treatments did not result in reductions in TN during the first two years of the treatment period. The contour strip and agroforestry treatments reduced TN loss by 21 and 20%, respectively, during a large precipitation event in the third year. During the third year of treatments, nitrate N loss was reduced 24 and 37% by contour strip and agroforestry treatments. Contour strip and agroforestry management practices effectively reduced nonpoint-source pollution in runoff from a corn-soybean rotation in the clay pan soils of northeastern Missouri.  相似文献   
122.
An approach to the study of social support at work is presented emphasizing nature and type of social support. One hundred employees in a range of occupations rated the frequency of engaging in 12 types of social and work-related activity with each of four work colleagues varying in degree of intimacy. They also rated levels of job satisfaction and work stress. The results confirm the usefulness of this approach and also suggest that type of work relationship is associated with different sorts of socially supportive activities, and that these affect stress but not satisfaction. These findings were discussed in terms of the interaction between type of support given, source of support, and outcome.  相似文献   
123.
The primary objective of this paper is to examine and inform the mental health and psychosocial support standards of the 2011 edition of the Sphere Project's Humanitarian Charter and Minimum Standards in Humanitarian Response. This is done through a qualitative analysis of internal evaluation documents, reflecting four long‐term humanitarian psychosocial programmes in different countries in post‐tsunami Asia. The analysis yielded three overall conclusions. First, the Sphere standards on mental health and psychosocial support generally are highly relevant to long‐term psychosocial interventions after disasters such as the Indian Ocean tsunami of 26 December 2004, and their application in such settings may improve the quality of the response. Second, some of the standards in the current Sphere handbook may lack sufficient guidance to ensure the quality of humanitarian response required. Third, the long‐term intervention approach poses specific challenges to programming, a problem that could be addressed by including additional guidance in the publication.  相似文献   
124.
Passive techniques are a constantly evolving approach to the long-term monitoring of micropollutants, including pharmaceuticals, in the aquatic environment. This paper presents, for the first time, the calibration results of a new CNTs-PSDs (carbon nanotubes used as a sorbent in passive sampling devices) with an examination of the effect of donor phase salinity, water pH and the concentration of dissolved humic acids (DHAs), using both ultrapure and environmental waters. Sampling rates (Rs) were determined for the developed kinetic samplers. It has been observed that the impact of the examined environmental factors on the Rs values strictly depends on the type of the analytes. In the case of β-blockers, the only environmental parameter affecting their uptake rate was the salinity of water. A certain relationship was noted, namely the higher the salt concentration in water, the lower the Rs values of β-blockers. In the case of sulfonamides, water salinity, water pH 7–9 and DHAs concentration decreased the uptake rate of these compounds by CNTs-PSDs. The determined Rs values differed in particular when the values obtained from the experiments carried out using ultrapure water and environmental waters were compared. The general conclusion is that the calibration of novel CNTs-PSDs should be carried out under physicochemical conditions of the aquatic phase that are similar to the environmental matrix.  相似文献   
125.
In three phases, this study identifies and evaluates the major messages being used in communication campaigns focused on the ongoing drought in California. A literature review in Phase 1 resulted in a typology of 12 message strategies. Following this typology, trained coders in Phase 2 evaluated water conservation messages (N?=?100) to determine whether each message utilized one or multiple strategies. The results revealed various frequencies of strategy application; and a correlational analysis rendered a pattern of strategy use in combinations. Phase 3 focused on a controlled message experiment applying the three most relevant strategies: conservation tips, loss aversion, and evidence of drought. Analysing data sampled from California residents (N?=?180), conservation messages, regardless of the strategy, led to attitude change in a negative direction. Additional analyses revealed interesting patterns of combinatorial strategy effects. The results call for a re-examination of message strategies as they may lead to several unfavourable outcomes.  相似文献   
126.
This paper raises questions of media coverage of “compounded crises” related to extreme weather disaster, in the context of urgent calls to address the implications of a changing climate. Through media analysis, it examines the ways debate over bushfire protection policy was framed and made culturally meaningful, thereby politically consequential, in the wake of the worst bushfires in modern Australian history, Black Saturday (2009). The fires, in which 173 people died, led to a Royal Commission and fierce debate over the use of prescribed burning to reduce bushfire hazard. Longitudinal analysis of local, state and national mainstream media coverage (2009–2016) reveals blame games that targeted environmentalists and the government, which near-silenced meaningful discussion of the complexity of fire science, impacts of climate change on weather conditions, and calls for adaptation. By exploring the media’s constitutive role in crisis response, the paper highlights the legacy and potency of ideological conflict that shapes the media-policy nexus in Australia.  相似文献   
127.
Environmental Science and Pollution Research - The aim of this study was to analyze the occurrence of sulfonamide resistance genes (sul1–3) and other genetic elements as antiseptic resistance...  相似文献   
128.
Livestock can contribute to climate change mitigation by reducing their greenhouse gas emissions and by increasing soil carbon sequestration. Packages of mitigation techniques can bring large environmental benefits as illustrated in six case studies modeled in the Global Livestock Environmental Assessment Model developed by FAO. With feasible technical interventions in livestock production systems, the mitigation potential of each of the selected species, systems and regions ranges from 14 to 41 %. While comparably high mitigation potentials were estimated for ruminant and pig production systems in Asia, Latin America and Africa, large emission reductions can also be attained in dairy systems with already high levels of productivity, in OECD countries. Mitigation interventions can lead to a concomitant reduction in emissions and increase in production, contributing to food security. This is particularly the case for improved feeding practices and better health and herd management practices. Livestock systems also have a significant potential for sequestrating carbon in pasturelands and rangelands through improved management, as illustrated in two of the six case studies in this paper.  相似文献   
129.
In the framework of the German environmental specimen bank one-year old spruce shoots (Picea abies) and pine shoots (Pinus sylvestris) serve as bioindicators for the atmospheric pollution. Sampling is performed in two urbanized areas in western and eastern Germany (Warndt and Duebener Heide, respectively), and in seven different rural locations. Prior to archiving conifer shoots are continuously analyzed for a set of 17 individual polycyclic aromatic hydrocarbons (PAHs). The results from the two urbanized areas show that the atmospheric contamination with PAH has declined by about 75% between 1985 and 2004 at Warndt and by about 85% between 1991 and 2004 at Duebener Heide. However, summation operatorPAH concentrations stayed virtually constant at both locations since the end of the 1990s at levels of about 100 ng g(-1) wet weight (ww). In spruce shoots from rural areas current concentrations of PAHs are significantly lower and vary between 8 and 61 ng g(-1) ww. In all shoot samples the four low molecular aromatics phenanthrene, fluoranthene, pyrene, and chrysene dominate the pattern by contributing 60 to 90% to summation operatorPAH. The group of high molecular weight aromatics is dominated by benzo[b,j,k]fluoranthene, especially in spruce shoots originating from greater altitudes remarkable amounts of six and seven ringed PAHs could be detected. Despite the strong decrease of PAH concentrations in urban areas patterns of aromatics remained nearly unchanged in the observation period 1985 to 2004.  相似文献   
130.
A linear engineering project--i.e. a pipeline--has a potential long- and short-term impact on the environment and on the inhabitants therein. We must find better, less expensive, and less time-consuming ways to obtain information on the environment and on any modifications resulting from anthropic activity. We need scientifically sound, rapid and affordable assessment and monitoring methods. Construction companies, industries and the regulating government organisms lack the resources needed to conduct long-term basic studies of the environment. Thus there is a need to make the necessary adjustments and improvements in the environmental data considered useful for this development project. More effective and less costly methods are generally needed. We characterized the landscape of the study area, situated in the center and north-east of Argentina. Little is known of the ecology of this region and substantial research is required in order to develop sustainable uses and, at the same time, to develop methods for reducing impacts, both primary and secondary, resulting from anthropic activity in this area. Furthermore, we made an assessment of the environmental impact of the planned linear project, applying an ad hoc impact index, and we analyzed the different alternatives for a corridor, each one of these involving different sections of the territory. Among the alternative corridors considered, this study locates the most suitable ones in accordance with a selection criterion based on different environmental and conservation aspects. We selected the corridor that we considered to be the most compatible--i.e. with the least potential environmental impact--for the possible construction and operation of the linear project. This information, along with suitable measures for mitigating possible impacts, should be the basis of an environmental management plan for the design process and location of the project. We pointed out the objectivity and efficiency of this methodological approach, along with the possibility of integrating the information in order to allow for the application thereof in this type of study.  相似文献   
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