Resident Motivations and Willingness-to-Pay for Urban Biodiversity Conservation in Guangzhou (China)

The monetary assessment of biodiversity measures the welfare damages brought by biodiversity losses and the cost-benefit analysis of conservation projects in a socio-economic context. The contingent valuation method could include motivational factors to strengthen economic analysis of nature conservation. This study analyzed Guangzhou residents’ motivations and willingness-to-pay (WTP) for an urban biodiversity conservation program in the National Baiyun Mountain Scenic Area (BMSA). The peri-urban natural site, offering refuge to some endemic species, is under increasing development pressures for recreational and residential use. A questionnaire survey was conducted in the Guangzhou metropolitan area during June to October 2007. We interviewed face-to-face 720 stratified sampled households to probe residents’ attitudes towards the city’s environmental issues, motivations for urban nature conservation, and WTP for biodiversity conservation. Principal component analysis identified five motivational factors, including environmental benefit, ecological diversity, nature-culture interaction, landscape-recreation function, and intergenerational sustainability, which illustrated the general economic values of urban nature. Logistic regression was applied to predict the probability of people being willing to pay for the urban biodiversity conservation in BMSA. The significant predictors of WTP included household income and the factor nature-culture interaction. The median WTP estimated RMB149/household (about US$19.5/household) per year and an aggregate of RMB291 million (approximately US$19.5/household) per year and an aggregate of RMB291 million (approximately US38.2 million) annually to support the urban conservation project. Including public motivations into contingent valuation presents a promising approach to conduct cost-benefit analysis of public projects in China.     

Building the role of local government authorities towards the achievement of the human right to water in rural Tanzania

In recent decades, many changes have occurred in the approach to financing and operating water services in developing countries. The demand‐responsive approach is now adopted in many countries in a context of donor‐supported decentralization processes, which gives more responsibility to end users. However, the government's responsibility at different levels is enforced by the international recognition of the human right to water. This paper examines specific actions that build the role of local government authorities in this scenario. A collaboration between an international NGO and a rural district in Tanzania from 2006 to 2009 is used as an action research case study that is representative of local capacity‐building needs in decentralized contexts and rural areas. Three main challenges were detected: i) lack of reliable information; ii) poor allocation of resources in terms of equity; and iii) lack of long‐term community management support from the district. Two mechanisms were established: i) water point mapping as a tool for information and planning; and ii) a District Water and Sanitation Unit Support (DWUS) for community management. The results show how the framework provided by the goal of human right to water helps to define useful strategies for equity‐oriented planning and post‐project support at the local level.     

Solvent Extraction Processes: A Survey of Systems in the SITE Program

Solvent extraction of contaminated soils, sludges and sediments has been successfully completed at a number of Superfund sites. Each commercialized process uses a unique operating system to extract organic contaminants from solids. These operating systems may be classified by the properties of the solvents each utilizes: (1) standard solvents, (2) near-critical fluids/liquified gases, and (3) critical solution temperature solvents. Pretreatment and post-treatment requirements vary depending upon the operating systems of the solvent extraction system. Future demonstrations of these technologies by the U.S. EPA’s Superfund Innovative Technology Evaluation Program will provide additional information regarding the efficacy of these processes.     

High-Mileage Study of On-Board Diagnostic Emissions

Abstract

The 1990 Clean Air Act amendments require the U.S. Environmental Protection Agency (EPA) to set guidelines for states to follow in designing and running vehicle inspection and maintenance (I/M) programs. Included in this charge was a requirement to implement an on‐board diagnostic (OBD) test for both basic and enhanced I/M programs. This paper provides the results to date of an ongoing EPA study undertaken to assess the durability of the OBD system as vehicles age and as mileage is accrued. The primary results of this effort indicate the points described below. First, the majority of high‐mileage vehicles tested had emission levels within their certification limits, and their malfunction indicator light (MIL) was not illuminated, indicating that the systems are capable of working throughout the life of a vehicle. Second, OBD provides better air quality benefits than an IM240 test (using the federal test procedure [FTP] as the benchmark comparison). This statement is based on greater emissions reductions from OBD‐directed repairs than reductions associated with IM240‐identified repairs. In general, the benefits of repairing the OBD fails were smaller, but the aggregate benefits were greater, indicating that OBD tests find both the high‐emitting and a number of marginally high‐emitting vehicles without false failures that can occur with any tailpipe test. Third, vehicles that truly had high‐tailpipe emissions as confirmed by laboratory IM240 and FTP testing also had illuminated MILs at a statistically significant level. Last, field data from state programs have demonstrated MIL illumination rates comparable with those seen in this work, suggesting that the vehicles sampled in this study were representative of the larger fleet. Nonetheless, it is important to continue the testing of high‐mileage OBD vehicles into the foreseeable future to ensure that the systems are operating correctly as the fleet ages and as changes in emission certification levels take effect.     

Realistic retrospective dose assessments to members of the public around Spanish nuclear facilities

In the frame of an epidemiological study carried out in the influence areas around the Spanish nuclear facilities (ISCIII-CSN, 2009. Epidemiological Study of The Possible Effect of Ionizing Radiations Deriving from The Operation of Spanish Nuclear Fuel Cycle Facilities on The Health of The Population Living in Their Vicinity. Final report December 2009. Ministerio de Ciencia e Innovación, Instituto de Salud Carlos III, Consejo de Seguridad Nuclear. Madrid. Available from: http://www.csn.es/images/stories/actualidad_datos/especiales/epidemiologico/epidemiological_study.pdf), annual effective doses to public have been assessed by the Spanish Nuclear Safety Council (CSN) for over 45 years using a retrospective realistic-dose methodology. These values are compared with data from natural radiation exposure. For the affected population, natural radiation effective doses are in average 2300 times higher than effective doses due to the operation of nuclear installations (nuclear power stations and fuel cycle facilities). When considering the impact on the whole Spanish population, effective doses attributable to nuclear facilities represent in average 3.5 × 10⁻⁵ mSv/y, in contrast to 1.6 mSv/y from natural radiation or 1.3 mSv/y from medical exposures.     

Estimating contaminant mass discharge: a field comparison of the multilevel point measurement and the integral pumping investigation approaches and their uncertainties

In this field study, two approaches to assess contaminant mass discharge were compared: the sampling of multilevel wells (MLS) and the integral groundwater investigation (or integral pumping test, IPT) that makes use of the concentration-time series obtained from pumping wells. The MLS approached used concentrations, hydraulic conductivity and gradient rather than direct chemical flux measurements, while the IPT made use of a simplified analytical inversion. The two approaches were applied at a control plane located approximately 40m downgradient of a gasoline source at Canadian Forces Base Borden, Ontario, Canada. The methods yielded similar estimates of the mass discharging across the control plane. The sources of uncertainties in the mass discharge in each approach were evaluated, including the uncertainties inherent in the underlying assumptions and procedures. The maximum uncertainty of the MLS method was about 67%, and about 28% for the IPT method in this specific field situation. For the MLS method, the largest relative uncertainty (62%) was attributed to the limited sampling density (0.63 points/m(2)), through a novel comparison with a denser sampling grid nearby. A five-fold increase of the sampling grid density would have been required to reduce the overall relative uncertainty for the MLS method to about the same level as that for the IPT method. Uncertainty in the complete coverage of the control plane provided the largest relative uncertainty (37%) in the IPT method. While MLS or IPT methods to assess contaminant mass discharge are attractive assessment tools, the large relative uncertainty in either method found for this reasonable well monitored and simple aquifer suggests that results in more complex plumes in more heterogeneous aquifers should be viewed with caution.     

Acetone and 2‐butanone creation associated with biological and chemical remediation of environmental contamination

Remediating environmental contamination by either biological or chemical methods typically results in the generation of temporary chemical intermediates as part of the process. These intermediate compounds may be related to either contaminant degradation pathways or reactions generated from the amendment itself. This article summarizes previously researched pathways and representative case studies discussing the authors' experience in generating relatively high concentrations of acetone and 2‐butanone (also referred to as methyl ethyl ketone [MEK]) during both biological and chemical treatments. Experience shows that even relatively high concentrations of acetone and MEK intermediates are quickly attenuated and prove not to be a hazard outside of the treatment area. © 2011 Wiley Periodicals, Inc.     

Trends in environmental education for biodiversity conservation in Costa Rica

Costa Rica is internationally recognized for its abundant biodiversity and being a leader in the promotion of education strategies for biodiversity conservation. We interviewed staff from 16 institutions developing key environmental communication, education, and participation projects for biodiversity conservation in the country. Through content analysis, hierarchical cluster analysis and Chi-square tests, we examined the characteristics of the projects carried out by these institutions and developed a typology of four categories derived from six variables: primary audience, content, project purpose, location, scale, and facility. Then, we designed a conceptual model describing the integration of conservation and economic development in the educational projects. We found two key approaches related to this integration: vision of nature protection which aims to inform audiences of ecological concepts and focuses on schoolchildren and vision of sustainability which engages adult audiences and is management-oriented. Education for community-based environmental management may serve as a good example of educational projects which integrate conservation and economic development, implementing a vision of sustainability.     

Physical and chemical changes during composting of wood chip-bedded and straw-bedded beef cattle feedlot manure

In the 1990s, restrictions on incineration encouraged the forest industry in western Canada to develop new uses for their wood residuals by product. One such use was as a replacement for cereal straw bedding in southern Alberta's beef cattle (Bos taurus) feedlot industry. However, use of carbon (C)-rich bedding, such as wood chips, had implications for subsequent composting of the feedlot manure, a practice that was being increasingly adopted. In a 3-yr study, we compared composting of wood chip-bedded manure (WBM) and barley (Hordeum vulgare L.) straw-bedded manure (SBM). There were no significant differences in temperature regimes of SBM and WBM, indicating similar rates of successful composting. Of 17 physical and chemical parameters, five showed significant (P < 0.10) differences due to bedding at the outset of composting (Day 0), and 11 showed significant differences at final sampling (Day 124). During composting (10 sampling times), seven parameters showed significant bedding effects, 16 showed significant time effects, and four showed a Bedding x Time interaction. Significantly lower (P < 0.10) losses of nitrogen (N) occurred with WBM (19%) compared with SBM (34%), which has positive implications for air quality and use as a soil amendment. Other advantages of WBM compost included significantly higher total C (333 vs. 210 kg Mg(-1) for SBM) and inorganic N (1.3 vs. 1.0 kg Mg(-1) for SBM) and significantly lower total phosphorus (4.5 vs. 5.3 kg Mg(-1) for SBM). Our results showed that wood chip bedding should not be a problem for subsequent composting of the manure after pen cleaning. In combination with other benefits, our findings should encourage the adoption of wood chips over straw as a bedding choice for southern Alberta feedlots.