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1.
Amending poultry litter with Al sulfate (alum) has proven effective in reducing water-soluble P in the litter and in runoff from fields that have received litter applications. Although its effectiveness has been demonstrated on a macroscopic scale in the field or in the poultry houses, little is known about P speciation in either alum-amended or unamended litter. This knowledge is important for the evaluation of long-term stability and bioavailability of P, which is a necessary prerequisite for the assessment of the sustainability of intensive poultry operations. Here we report results from an investigation of alum-amended poultry litter (PL) that combined a chemical extraction sequence with solid-state 31P nuclear magnetic resonance (NMR) spectroscopic analysis of the residues. Aluminum is predominantly found in the fine size separate (<125 microm), indicating that the alum added to the poultry houses hydrolyzed without being completely dispersed in the litter. The NMR spectra confirmed the hypothesis that calcium phosphate phases are only dissolved during extraction with dilute acid and phosphate associated with Al is mainly dissolved during extraction with NaOH. Extraction of phosphate associated with Al was incomplete, however, as evidenced by 31P NMR spectroscopy. It could also be demonstrated that the extraction sequence overestimates the calcium phosphate fraction by an order of magnitude in this particular sample. Results from sequential chemical extraction should therefore be used with caution when assessing the magnitude of different phosphate pools in poultry litter.  相似文献   

2.
Testing for the existence of downward trends in real commodity prices has been the focus of several studies since the Prebisch–Singer hypothesis was formulated back in 1950. In this article, we focus on annual and monthly series of various commodity categories and consider alternative price deflators. Based on the methodology of Harvey et al. (2010), which is robust to the order of integration of the time series, we conclude that the time frequency and the price deflators play a key role when testing for the Prebisch–Singer hypothesis. For instance, at an annual frequency (1900–2003, 1900–2008), it becomes considerably more likely to support it when deflating by the unadjusted US CPI-all items than when deflating by the Manufactures Unit Value (MUV) Index or the Historical Price Index of Manufactures (HPIM). This finding is in agreement with the Svedberg and Tilton (2006) discussion on the CPI's overestimation of inflation and the measurement of the real price of copper. When dealing with monthly data (January 1957–December 2010), our results show that real prices tend not to reject the null hypothesis of a trendless series, except when deflating by the PPI-Crude Materials and, to a lesser extent, by the HPIM.  相似文献   

3.
Environmental Management - In the United States, forest governance practices have utilized a variety of public participation mechanisms to improve decision-making and instill public legitimacy....  相似文献   

4.
Cruise, James F., Charles A. Laymon, and Osama Z. Al-Hamdan, 2010. Impact of 20 Years of Land-Cover Change on the Hydrology of Streams in the Southeastern United States. Journal of the American Water Resources Association (JAWRA) 46(6):1159–1170. DOI: 10.1111/j.1752-1688.2010.00483.x Abstract: Land-cover changes for portions of Alabama, Georgia, and Tennessee were estimated for the years 1980, 1990, and 2000 using classified Landsat images, and associated with hydrologic indices for 12 watersheds in the region. Rainfall-adjusted mean annual streamflow, an ET proxy (precipitation minus runoff), frequency of inundation above thresholds, and duration of inundation were used to characterize the hydrologic response of the test basins over the two-decade study period. Results indicate that several of the watersheds had undergone significant (>20%) reductions in agricultural land cover with a coincident increase in forested land. Attempts to correlate the hydrologic results with the land-cover changes were only partially successful. Watersheds with the largest land conversion from agriculture to forest (20% or more) did show significant trends in hydrologic indices indicating decreasing streamflow; however, other basins evidenced ambiguous results. The net conclusions of the study are that land-cover effects on hydrologic variables may be nuanced and can sometimes be only indirectly evident, and that a rigorous and detailed land-cover classification effort along with a battery of statistical tests with the same objective may be necessary to uncover these effects.  相似文献   

5.
Galloway, Gerald E., 2011. If Stationarity Is Dead, What Do We Do Now? Journal of the American Water Resources Association (JAWRA) 47(3):563‐570. DOI: 10.1111/j.1752‐1688.2011.00550.x Abstract: In January 2010, hydrologists, climatologists, engineers, and scientists met in Boulder, Colorado, to discuss the report of the death of hydrologic stationarity and the implications this might have on water resources planning and operations in the United States and abroad. For decades planners have relied on design guidance from the Interagency Advisory Committee on Water Data Bulletin 17B that was based upon the concept of stationarity. After 2½ days of discussion it became clear that the assembled community had yet to reach an agreement on whether or not to replace the assumption of stationarity with an assumption of nonstationarity or something else. Hydrologists were skeptical that data gathered to this point in the 21st Century point to any significant change in river parameters. Climatologists, on the other hand, point to climate change and the predicted shift away from current conditions to a more turbulent flood and drought filled future. Both groups are challenged to provide immediate guidance to those individuals in and outside the water community who today must commit funds and efforts on projects that will require the best estimates of future conditions. The workshop surfaced many approaches to dealing with these challenges. While there is good reason to support additional study of the death of stationarity, its implications, and new approaches, there is also a great need to provide those in the field the information they require now to plan, design, and operate today’s projects.  相似文献   

6.
The basin scale has been promoted universally as the optimal management unit that allows for the internalization of all external effects caused by multiple water uses. However, the basin scale has been put forward largely on the basis of experience in temperate zones. Hence whether the basin scale is the best scale for management in other settings remains questionable. To address these questions this paper analyzes the economic viability and the political feasibility of alternative management options in the Kidron/Wadi Nar region. The Kidron/Wadi Nar is a small basin in which wastewater from eastern Jerusalem flows through the desert to the Dead Sea. Various options for managing these wastewater flows were analyzed ex ante on the basis of both a cost benefit and a multi-criteria analysis. The paper finds that due to economies of scale, a pure basin approach is not desirable from a physical and economic perspective. Furthermore, in terms of political feasibility, it seems that the option which prompts the fewest objections from influential stakeholder groups in the two entities under the current asymmetrical political setting is not a basin solution either, but a two plant solution based on an outsourcing arrangement. These findings imply that the river basin management approach can not be considered the best management approach for the arid transboundary case at hand, and hence is not unequivocally universally applicable.  相似文献   

7.
Wildfires are a common feature of peatland environments, but the carbon balance of these wildfires is often not considered and the production of refractory black carbon in these wildfires could be an important addition to carbon accumulation and mitigate losses of biomass during the fire. This study investigates the biomass and carbon losses during a moorland wildfire. Changes in above-ground carbon stocks were calculated using a combination of field data, laboratory measurements and literature values. The results show that approximately 14% of the carbon in the original above-ground biomass remained on the site after the burn. Black carbon production was approximately 6 gC m(-2) which constituted 4.3% of the biomass lost. The survival of biomass and black carbon may help to mitigate the loss of carbon during the fire.  相似文献   

8.
Although contingent valuation is widely discussed in the literature as a technique for environmental valuation, it is well recognized that a number of problems are associated with its use. This paper seeks to address two of these problems: the difficulty of externally verifying the results of a CV study; and the choice of an appropriate level of information to provide to respondents. Four sites were evaluated, first by expert ecologists and then by the general public using the CV method. In conducting the CV, six different categories of information were presented to different groups of respondents to test which was most appropriate.The results show that, given an information set consisting of photographic,textual and ecological data, respondents to a CV study were able to rank the four sites in the same order as ecological experts. This may be seen as a form of external verification to the results of the contingent valuation.  相似文献   

9.
According to the environmental justice (EJ) literature, one important factor in the movement's success is the development of a frame linking inequality to the disproportionate presence of environmental toxins in low-income communities of colour. This article highlights the resonance of this frame among grassroots activists and professional advocates in California's Central Valley. However, through interviews and focus groups with activists and advocates in six Central Valley communities, we found that only the latter identified their work as EJ. Grassroots activists instead identified their work as about health, community development and environmentalism. Moreover, some were unfamiliar with EJ as a concept while others denied its applicability to their work. Theoretically, our findings suggest that frame resonance needs to be delinked conceptually from movement identification; it is possible for a movement's analysis of social problems and solutions to resonate among those who do not identify with the movement itself. Pragmatically speaking, this can prevent some grassroots activists who are directly affected by environmental racism from accessing the resources and networks that the EJ movement has painstakingly built, and suggests that movement leaders may need to increase their outreach to community groups.  相似文献   

10.
This article investigates the involvement of local stakeholders in the environmental impact assessment (EIA) processes of Ghana’s first off-shore oil fields (the Jubilee fields). Adopting key informants interviews and documentary reviews, the article argues that the public hearings and the other stakeholder engagement processes were cosmetic and rhetoric with the view to meeting legal requirements rather than a purposeful interest in eliciting inputs from local stakeholders. It further argues that the operators appear to lack the social legitimacy and social license that will make them acceptable in the project communities. A rigorous community engagement along with a commitment to actively involving local stakeholders in the corporate social responsibility (CSR) programmes of the partners may enhance the image of the partners and improve their social legitimacy. Local government agencies should be capacitated to actively engage project organisers; and government must mitigate the impact of the oil projects through well-structured social support programmes.  相似文献   

11.
The fate of used electronic products (e-waste) is of increasing concern because of their toxicity and the growing volume of e-waste. Addressing these concerns requires developing the recycling infrastructure, but good estimates of the volume of e-waste stored by US households are still unavailable. In this context, we make two contributions based on a national random survey of 2136 US households. First, we explain how much e-waste is stored by US households using count models. Significant explanatory variables include age, marital and employment status, ethnicity, household size, previous e-waste recycling behavior, and to some extent education, home ownership, and understanding the consequences of recycling, but neither income nor knowledge of e-waste recycling laws. Second, we estimate that on average, each US household has 4.1 small (≤10 pounds) and 2.4 large e-waste items in storage. Although these numbers are likely lower bounds, they are higher than recent US Environmental Protection Agency (EPA) estimates (based on narrower product categories). This suggests that the backlog of e-waste in the US is likely larger than generally believed; it calls for developing the recycling infrastructure but also for targeted recycling campaigns.  相似文献   

12.
This paper considers the stability of public responses to an urban river restoration scheme on the River Skerne, Darlington, UK, by comparing the results from surveys of local residents carried out before and after scheme implementation. This case study provides evidence of strong and generally consistent positive responses to the proposals and implemented scheme to return the straightened and channelized river to a more natural condition although support was more qualified after than before implementation. Although the scheme design and construction costs were high, nearly two-thirds regarded the scheme as value for money. Exploratory contingent valuation results on whether or not local residents were prepared to pay for the scheme were broadly stable over the two surveys.  相似文献   

13.
To examine ownership and protection status of forests with high-biomass stores (>200 Mg/ha) in the Pacific Northwest (PNW) region of the United States, we used the latest versions of publicly available datasets. Overlay, aggregation, and GIS-based computation of forest area in broad biomass classes in the PNW showed that the National Forests contained the largest area of high-biomass forests (48.4 % of regional total), but the area of high-biomass forest on private lands was important as well (22.8 %). Between 2000 and 2008, the loss of high-biomass forests to fire on the National Forests was 7.6 % (236,000 ha), while the loss of high-biomass forest to logging on private lands (364,000 ha) exceeded the losses to fire across all ownerships. Many remaining high-biomass forest stands are vulnerable to future harvest as only 20 % are strictly protected from logging, while 26 % are not protected at all. The level of protection for high-biomass forests varies by state, for example, 31 % of all high-biomass federal forests in Washington are in high-protection status compared to only 9 % in Oregon. Across the conterminous US, high-biomass forest covers <3 % of all forest land and the PNW region holds 56.8 % of this area or 5.87 million ha. Forests with high-biomass stores are important to document and monitor as they are scarce, often threatened by harvest and development, and their disturbance including timber harvest results in net C losses to the atmosphere that can take a new generation of trees many decades or centuries to offset.  相似文献   

14.
15.
Natural hazard investigators recommend that local governments adopt mitigation plans to help reduce hazard losses. However, such plans are unlikely to be effective unless a wide range of public stakeholders is involved in their creation. Previous research shows that stakeholder participation levels in hazard mitigation planning tend to be low, though there may be particular choices that local government planners can make to foster participation. We examine the importance of planners’ choices and role orientations (i.e., beliefs regarding appropriate behavior in the workplace) for participation levels in site plan review, wherein local governments review site plans for proposed development projects to ensure compliance between project design and applicable plans and policies. Using a national sample of 65 development projects located in areas subject to natural hazards, and bivariate and multivariate analyses, we examine whether participation levels during site plan review depend upon planners’ choices and role orientations, and whether participation levels are correlated with the incorporation of hazard mitigation techniques into development projects. We find significant correlations between participation levels and planners’ choices, between participation levels and planner’s role orientations, and between participation levels and the incorporation of hazard mitigation techniques. We encourage local government planners to revisit their beliefs, choices, and behaviors regarding public participation in site plan review.  相似文献   

16.
Inclusive recycling is the inspiring slogan of a project relying on a cross-sector (public–private–civil society) partnership implemented in Latin America with the objective to improve the socioeconomic conditions of recyclers. Through a qualitative study in Santiago de Chile, this paper seeks to understand how inclusive inclusive recycling is, by assessing how organised recyclers perceive the goals, the process, and the outcomes of this project. The main findings converge in observing a general low inclusion of recyclers, but they also enable to decompose the notion of inclusion into three dimensions: “inclusive goals” refers to the extent to which the goals of the recyclers are taken into account when designing the collaboration project; “inclusive process” refers to the extent to which recyclers are involved in the process of implementing the project; and “inclusive outcomes” refers to the capacity of the partnership to acknowledge the achievements of recyclers organisations before (and during) the project and to take into account the ongoing local dynamics when evaluating the project. These findings contribute to better understand the position and challenges of recyclers in this type of partnership and more generally to shed light on the potential power imbalance in waste management cross-sector partnerships.  相似文献   

17.
What makes a food good, for you? With respect to food, the expression “good for you” usually refers to the effect of the food on the nutritional health of the eater, but it can also pertain more broadly. The expression is often used by a person who is concerned with another person’s well-being, as part of an exhortation. But when framed as a question and addressed to you, as an individual, the question can require a response, calling for accountability beyond the realm of nutrition or other material qualities of the food. Economic value may be considered as a ratio: goodness/price. In this paper, we examine the numerator, exploring a broad range of values domains related to food, attempting to obtain a more comprehensive understanding of the meaning of goodness of food. We present a typology of values domains with respect to food, divided into three main categories: (1) material considerations, (2) psychological, psychosocial, and spiritual health, and (3) the well-being of society. This understanding that results from comprehensive consideration of these values domains has important implications for an individual for use in considering the question “what food is good for you?” in order to guide his or her future actions, helping to distinguish between what Dewey termed immediate good and reasonable good. A pragmatic approach to a fuller consideration of food-related values domains by individuals also has broad social, political, and economic implications. If, according to the FAO, food security involves both needs and preferences, consideration of what preferences are appropriate is fundamental to achieving food security. The questions about what is considered to be good food are central to questions about the sorts of food and agricultural systems human societies will seek to sustain. The approach to resolving this important aspect of sustainability might help inform a more general question as to appropriate limitations on preferences, a question fundamental to achieving sustainability in general.  相似文献   

18.
In Finland, the current water conservation policy sets equal incentives for water conservation, regardless of the environmental condition. Before any policy reform, it is vital to investigate the tendency of landowners to adopt water conservation measures. In this study, we were interested in examining adoption if the soil quality implies a high leaching risk and if the water quality is already poor. By combining survey data with GIS data, we analysed the effect of farm and farmer characteristics and attitudes towards adoption. Our probit models indicated that financial variables were the key determinants of adoption for active farmers, whereas for passive owners, adoption was also explained by attitudes. In contrast to our expectations, adoption in areas under risk was weakly supported by our estimates. Environmental awareness, providing it increases with risk, is not strong enough to motivate adoption. Targeted agri-environmental measures, even though costly, cannot be avoided, and spatially tailored measures can attract adopters in hotspot areas.  相似文献   

19.
Policy-makers are interested in cost-effective and socially acceptable ways of encouraging the public to adopt more environmentally-friendly lifestyles. One area which UK policy-makers are focussing on is ‘catalyst behaviour’, the notion that taking-up a new behaviour (such as recycling) may cause people to adopt other pro-environmental behaviours. Yet, evidence for such ‘spill-over’ effects is so far limited, and it is unclear when and how cross-situational motivations (e.g., pro-environmental identity) may predict behaviour and when contextual factors are more important. We report on a postal survey (N = 551) of pro-environmental behaviours amongst the UK public. We assess the influence of pro-environmental self-identify on consistency across a range of behaviours. Pro-environmental values, perceived behavioural control, subjective norm, attitudes, and demographic factors were also measured. Findings show self-identity to be a significant behavioural determinant over and above theory of planned behaviour variables for carbon offsetting behaviour. However, pro-environmental self-identity was only a significant predictor for certain other pro-environmental behaviours; background variables were also important predictors. Limitations of the study, and implications for theory and policy, are discussed.  相似文献   

20.
This research explores the attitudes of children from different socioeconomic backgrounds toward consumption with the aim of establishing a framework for incorporating the subject of (responsible) consumption into the upper elementary school curriculum. This study draws upon the four-step methodological procedure, including consumption diaries, focus-group sessions, interviews, and concept mapping, conducted among 140 upper elementary school children in the Netherlands between September 2010 and January 2011. The consumption diaries, chronological documents recording purchase, use and waste of materials, were used both as analytical tools and the means to stimulate environmental awareness. Comparison of the clusters generated by concept mapping analysis shows that there are significant differences between attitudes of children from different socioeconomic backgrounds. While pupils from the “well-to-do” predominantly ethnically Dutch schools showed greater awareness of and concern about their own consumptive patterns, children from less economically advantaged and ethnically mixed schools demonstrated lower environmental awareness and concern. However, children from the disadvantaged schools demonstrated more pro-environmental consumptive behaviors associated with the money-saving activities.  相似文献   

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