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101.
Setback distances between septic tank systems and the shorelines of Lake Okareka, New Zealand were determined from model simulations for a worst-case scenario, using the highest hydraulic conductivity and gradient measured in the field, removal rates of the microbial indicators (Escherichia coli and F-RNA phages) determined from a column experiment, and maximum values of the design criteria for the disposal system, and assuming an absence of an unsaturated zone, a continuous discharge of the raw effluent from a failed or non-complying treatment system (both indicators at concentrations of 1x10(7) counts/100 ml) into the groundwater and no sorption of pathogens in the aquifer. Modelling results suggest that the minimal setback distances were 16 m to satisfy the New Zealand Recreational Water Quality Guidelines for E. coli <126 per 100 ml (Ministry for the Environment, 1999) and 48 m to meet the Drinking-Water Standards for New Zealand 2000 for enteric virus <1 per 100 l (Ministry of Health, 2000). These distances may be applicable for other lakeshores in pumice sand aquifers with groundwater velocities <7 m/day. Findings of laboratory column and batch experiments provided an insight into the microbial attenuation and transport processes in pumice sand aquifers. Bacterial removal was predominately through filtration (87-88%) and partially by die-off (12-13%), while viral removal was by both die-off (45%) and filtration (55%). In addition, microbial die-off in groundwater without aquifer material (i.e., free microbes) was much lower than die-off in groundwater with aquifer material (i.e., sorbed microbes) and contributed only 2-6% to the total removal. This implies that the setback distances estimated from die-off rates for the free microbes, determined in the laboratory without considering aquifer media and other removal processes, which are often reported in the literature, could be larger than necessary.  相似文献   
102.
103.
Edmunds, Jake, Glenn Tootle, Greg Kerr, Ramesh Sivanpillai, and Larry Pochop, 2011. Glacier Variability (1967‐2006) in the Teton Range, Wyoming, United States. Journal of the American Water Resources Association (JAWRA) 48(1): 187‐196. DOI: 10.1111/j.1752‐1688.2011.00607.x Abstract: Glacier area and volume changes were quantified through the use of historical aerial photographs in Wyoming’s Teton Range. Glacier area changes in the Teton Range were estimated for three glaciers using unrectified aerial photography from 1967 to 2006. The total surface area of the three glaciers was 0.53 km2 in 1967 and 0.40 km2 in 2006, a decrease of 25% during the 39‐year period. The smallest glacier, Teepe, experienced the greatest area loss (60 ± 3%), whereas the largest glacier, Teton Glacier, lost 17 ± 3% of the 1967 area. For the current research, aerial photography from 1967 to 2002 was used to estimate glacier volume loss using stereoscopy techniques. The aerial photographs provide a finer resolution when compared with other datasets including satellite imagery (e.g., Landsat). Volume loss for the three glaciers was estimated to be 3.20 ± 0.46 million cubic meters over the period of 1967 to 2002. In assessing the primary climatic driver of the glacier ice loss, observed summer (June, July, and August) temperature data showed a statistically significant increase in temperatures when comparing the period of study (1968 to 2006) with historical temperatures from 1911 to 1967. When comparing spring (April 1st Snow Water Equivalent) snowpack for the period of study with historical records beginning in 1931, a significant difference in snowpack was not observed.  相似文献   
104.
Recovery plans are the main documents supporting management decision-making for threatened species. We evaluated Australian recovery plans to assess their appropriateness as conservation and management planning instruments. Six legislative requirements (species information and general requirements, species distribution and location, known and potential threats, objectives, performance criteria and actions, duration of the plan, and estimated costs of plan implementation) were used to assess the degree of compliance of recovery plans with the relevant legislation. We assessed all 236 official recovery plans which had been adopted as at January 2006. The results showed that plans were most compliant regarding the setting of objectives, performance criteria, recovery actions, and duration of plan. Most plans included a single performance criterion that was generally related to the population status of target species. Improvement is required in relation to identification of current threats and critical habitats, and the establishment of basic elements of monitoring and evaluation for measuring recovery progress. Gaps in ecological information are the main factors affecting adequate compliance with legislative requirements as opposed to managerial information (e.g. clarity in establishing the implementation schedule, costs and resource allocation). Planning deficiencies could be addressed by improving the recovery planning guidelines and more carefully reviewing the drafting and adoption of new plans.  相似文献   
105.
We compared the results from fixed acoustic transmitters and transmitters implanted in lingcod Ophiodon elongatus provided by two fine-scale passive acoustic monitoring systems: the older Vemco? Radio Acoustic Positioning (VRAP) system and the newer VR2W Positioning System (VPS) with either three or four receivers. The four-receiver VPS method calculated five times more positions of lingcod than VRAP and more than twice as many as the three-receiver VPS. Calculated positions of fixed transmitters were less precise with VRAP than either VPS approach. Measurements of home range for lingcod were similar between the four-receiver VPS and VRAP, which were both greater than the three-receiver VPS. Comparisons varied when lingcod were in/near complex habitats. As new technology develops, it is important to understand how new methods compare to previous methods. This may be important when describing patterns of movement or habitat use in the context of changes in habitat or management efforts.  相似文献   
106.
The Manawatu floods of 2004 have had significant, long-lasting social consequences. This paper draws on findings from a series of detailed surveys of 39 farm households directly affected by the floods and 17 individuals directly involved in managing the flood recovery programme. The nature of the impact on rural families highlights how the 'hollowing out' of rural New Zealand has changed the capacity of rural communities to respond to natural hazards and increased their sense of isolation. In addition, the floods exposed the vulnerability of rural communities. This is shown to have implications for policies designed to build resilience and improve responses to adverse events, including the need to support local, community initiatives on self-reliance and mutual support. Approaches to manage better long-term flood risks should be designed within a context of ongoing rural decline that has compromised the health of both individuals and communities.  相似文献   
107.
Agricultural irrigation accounts for a large fraction of the total water use in the western United States. The Mapping Evapotranspiration at high Resolution with Internalized Calibration (METRIC) remote sensing energy balance model is being used to estimate historical agricultural water use in western Nevada to evaluate basin‐wide water budgets. Each METRIC evapotranspiration (ET) estimate must be calibrated by a trained user, which requires some iterative time investment and results in variation in ET estimates between users. An automated calibration algorithm for the METRIC model was designed to generate ET estimates comparable to those from trained users by mimicking the manual calibration process. Automated calibration allows for rapid generation of METRIC ET estimates with minimal manual intervention, as well as uncertainty and sensitivity analysis of the model. The variation in ET estimates generated by the automated calibration algorithm was found to be similar to the variation in manual ET estimates. Results indicate that uncertainty was highest for fields with low ET levels and lowest for fields with high ET levels, with a seasonal mean uncertainty of approximately 5% for all fields. In addition, in a blind comparison, automated daily and seasonal ET estimates compared well with flux tower measurement ET data at multiple sites. Automated methods can generate first‐order ET estimates that are similar to time intensive manual efforts with less time investment.  相似文献   
108.

This paper provides an assessment of the tools required to fulfil the air quality management role now expected of local authorities within the UK. The use of a range of pollution monitoring tools in assessing air quality is discussed and illustrated with evidence from a number of previous studies of urban background and roadside pollution monitoring in Leicester. A number of approaches to pollution modelling currently available for deployment are examined. Subsequently, the modelling and monitoring tools are assessed against the requirements of local authorities establishing air quality management areas. Whilst the paper examines UK-based policy, the study is of wider international interest.  相似文献   
109.
Backyard garden sharing projects can be viewed as a small-scale alternative to traditional community gardens. These shared spaces are able to overcome some of the pressures on community gardens such as competing demands for housing and other services and amenities while still providing many of the health-promoting benefits community gardens are noted for. This study is a small-scale participatory qualitative project that explores three backyard garden sharing partnerships. The aim of this study is to explore the benefits and challenges of these shared spaces and to discuss the overall feasibility of shared backyard gardens. Partnerships comprised an older adult homeowner (i.e., greater than age 65) and a non-senior gardener. At an individual level, the results suggest that backyard garden sharing can promote physical activity, psychosocial well-being, and social connectedness for both older adult homeowners and volunteer garden partners. To be successful, partners benefit from an established agreement about what to grow and how to share the garden's produce. In addition, a dedicated project coordinator and a limited amount of community resources can ensure the viability of these small-scale projects.  相似文献   
110.
ABSTRACT

Originating in the UK in 2006, the Transition movement is oriented to local grassroots citizen-led efforts that prepare for and support a societal energy transition to a low-carbon future in response to climate change, peak oil, ecological degradation, and economic instability. Overlapping significantly with relocalization, degrowth/slow growth, local food, and related movements, and based on permaculture principles and a distributed network model, it embraces the opportunity to turn crisis into an opportunity to build more resilient, convivial, and vibrant local communities, declaring that “if it’s not fun, it’s not sustainable”. The Transition approach has spread rapidly around the world, including initiatives in over 100 communities and cities in Canada. This paper reports on the methods and results of a Canadian community-based research study aimed at understanding how and where the movement has taken root across the country, what Transition practice looks like, challenges and opportunities encountered, and lessons learned that could be applied within the movement and by others interested in the role of citizen-led initiatives for sustainability transition. Utilising a practice theory lens, drawing on an extensive web-scan of the movement’s online presence, a survey and interviews with initiative (co)founders, an e-survey of Transition members/participants, regional “structured story-dialogue” workshops, and key informant interviews, and informed by input from a Movement Advisory Group, we describe the research process and explore what success and impact mean to those most active in the movement.  相似文献   
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