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141.
Many alpine ski areas have recently adopted voluntary environmental programs (VEPs) such as using recycling, renewable energy,
and biofuels to help reduce their environmental impacts. Studies have addressed the performance of these VEPs in mitigating
environmental impacts of this industry, but little is known about visitor awareness and perceptions of these programs. This
article addresses this knowledge gap by exploring skier and snowboarder knowledge of VEPs at a ski area and the influence
of these programs on their motivations to visit this area currently and behavioral intentions to visit again in the future.
Data were obtained from an onsite survey at the Mt. Bachelor ski area in Oregon, USA (n = 429, 89.7% response rate). Few skiers and snowboarders were knowledgeable of VEPs at this area and fewer than 20% were
motivated to visit on their current trip because of these programs. Other attributes such as scenery, snow conditions, and
access were more important for influencing visitation. Up to 38% of skiers and snowboarders, however, intend to visit this
ski area more often if it adopts and promotes more VEPs. Managers can use these results to inform communication and marketing
of their environmental programs and performance to visitors. Additional implications for management and future research are
discussed. 相似文献
142.
Congruence Among Encounters,Norms, Crowding,and Management in a Marine Protected Area 总被引:1,自引:0,他引:1
Over the past few decades, recreation and tourism use has increased at many marine protected areas, generating concerns about
impacts of this increasing use on experiences and conditions at these areas (e.g., crowding, conflict). This article uses
data from Molokini Shoal Marine Life Conservation District in Hawai’i to examine: (a) reported encounters, crowding, normative
tolerances for various use levels, and support of use related management strategies at this site; and (b) whether users who
encounter higher use levels than their norms feel more crowded and are more supportive of restrictive management strategies.
Data were obtained from onsite pre-trip and post-trip questionnaires of 712 passengers on commercial snorkel and dive tours
visiting this site. Norms were measured with acceptance of 12 photographs depicting levels of boat use. On average, users
would accept seeing no more than approximately 16 boats at one time at Molokini and this number was observed on over 20% of
trips to the site. Although the majority of users expected to escape crowds at Molokini, 67% felt crowded and up to 79% supported
actions that would directly restrict use at this site (e.g., limit number of boats). Users who encountered more boats than
their normative tolerance felt more crowded and were more supportive of these management strategies. Findings suggest that
this marine protected area is operating over its capacity and management is needed to improve experiences and conditions. 相似文献
143.
Water governance has emerged as perhaps the most important topic of the international water community in the 21st century, and achieving “good” water governance is now a focus of both policy discourse and innumerable development projects. Somewhat surprisingly in light of this attention, there is widespread confusion about the meaning of the term “water governance”. This paper reviews the history of the term's use and misuse to reveal how the concept is frequently inflated to include issues that go well beyond governance. Further, it highlights how calls to improve water governance often espouse predetermined goals that should instead be the very function of water governance to define. To help overcome this confusion, the paper suggests a more refined definition of water governance and related qualities of good water governance that are consistent with broader notions of the concepts. In light of the substantial resources allocated in its name, this paper's findings show there is significant potential to strengthen efforts at improving water governance. 相似文献
144.
He J Dougherty M Shaw J Fulton J Arriaga F 《Journal of environmental management》2011,92(10):2479-2485
Rural areas represent approximately 95% of the 14000 km(2) Alabama Black Belt, an area of widespread Vertisols dominated by clayey, smectitic, shrink-swell soils. These soils are unsuitable for conventional onsite wastewater treatment systems (OWTS) which are nevertheless widely used in this region. In order to provide an alternative wastewater dosing system, an experimental field moisture controlled subsurface drip irrigation (SDI) system was designed and installed as a field trial. The experimental system that integrates a seasonal cropping system was evaluated for two years on a 500-m(2) Houston clay site in west central Alabama from August 2006 to June 2008. The SDI system was designed to start hydraulic dosing only when field moisture was below field capacity. Hydraulic dosing rates fluctuated as expected with higher dosing rates during warm seasons with near zero or zero dosing rates during cold seasons. Lower hydraulic dosing in winter creates the need for at least a two-month waste storage structure which is an insurmountable challenge for rural homeowners. An estimated 30% of dosed water percolated below 45-cm depth during the first summer which included a 30-year historic drought. This massive volume of percolation was presumably the result of preferential flow stimulated by dry weather clay soil cracking. Although water percolation is necessary for OWTS, this massive water percolation loss indicated that this experimental system is not able to effective control soil moisture within its monitoring zone as designed. Overall findings of this study indicated that soil moisture controlled SDI wastewater dosing is not suitable as a standalone system in these Vertisols. However, the experimental soil moisture control system functioned as designed, demonstrating that soil moisture controlled SDI wastewater dosing may find application as a supplement to other wastewater disposal methods that can function during cold seasons. 相似文献
145.
Pit lakes (abandoned flooded mine pits) represent a potentially valuable water resource in hot arid regions. However, pit lake water is often characterised by low pH with high dissolved metal concentrations resulting from Acidic and Metalliferous Drainage (AMD). Addition of organic matter to pit lakes to enhance microbial sulphate reduction is a potential cost effective remediation strategy. However, cost and availability of suitable organic substrates are often limiting. Nevertheless, large quantities of sewage and green waste (organic garden waste) are often available at mine sites from nearby service towns. We treated AMD pit lake water (pH 2.4) from tropical, North Queensland, Australia, with primary-treated sewage sludge, green waste, and a mixture of sewage and green waste (1:1) in a controlled microcosm experiment (4.5 L). Treatments were assessed at two different rates of organic loading of 16:1 and 32:1 pit water:organic matter by mass. Combined green waste and sewage treatment was the optimal treatment with water pH increased to 5.5 in only 145 days with decreases of dissolved metal concentrations. Results indicated that green waste was a key component in the pH increase and concomitant heavy metal removal. Water quality remediation was primarily due to microbially-mediated sulphate reduction. The net result of this process was removal of sulphate and metal solutes to sediment mainly as monosulfides. During the treatment process NH(3) and H(2)S gases were produced, albeit at below concentrations of concern. Total coliforms were abundant in all green waste-treatments, however, faecal coliforms were absent from all treatments. This study demonstrates addition of low-grade organic materials has promise for bioremediation of acidic waters and warrants further experimental investigation into feasibility at higher scales of application such as pit lakes. 相似文献
146.
Cook KL Rothrock MJ Eiteman MA Lovanh N Sistani K 《Journal of environmental management》2011,92(7):1760-1766
Poultry litter is a valuable nutrient source for crop production. Successful management to reduce ammonia and its harmful side-effects on poultry and the environment can be aided by the use of litter amendments. In this study, three acidifiers, two biological treatments, one chemical urease inhibitor and two adsorber amendments were added to poultry litter. Chemical, physical and microbiological properties of the litters were assessed at the beginning and the end of the experiment. Application of litter amendments consistently reduced organic N loss (0-15%) as compared to unamended litter (20%). Acidifiers reduced nitrogen loss through both chemical and microbiological processes. Adsorbent amendments (water treatment residuals and chitosan) reduced nitrogen loss and concentrations of ammonia-producing bacteria and fungi. The use of efficient, cost-effective litter amendments to maximum agronomic, environmental and financial benefits is essential for the future of sustainable poultry production. 相似文献
147.
Hydrologic and Phosphorus Export Behavior of Small Streams in Commercial Poultry‐Pasture Watersheds1
J. Joshua Romeis C. Rhett Jackson L. Mark Risse Andrew N. Sharpley David E. Radcliffe 《Journal of the American Water Resources Association》2011,47(2):367-385
Romeis, J. Joshua, C. Rhett Jackson, L. Mark Risse, Andrew N. Sharpley, and David E. Radcliffe, 2011. Hydrologic and Phosphorus Export Behavior of Small Streams in Commercial Poultry‐Pasture Watersheds. Journal of the American Water Resources Association (JAWRA) 1‐19. DOI: 10.1111/j.1752‐1688.2011.00521.x Abstract: Few watershed‐scale studies have evaluated phosphorus export in streamflow from commercial poultry‐pasture operations. Continuous streamflow and mixed‐frequency water quality datasets were collected from nine commercial poultry‐pasture (AG) and three forested (FORS) headwater streams (2.4‐44 ha) in the upper Etowah River basin of Georgia to estimate total P (TP) loads and examine variability of hydrologic response and water quality of storm and nonstorm‐flow regimes. Data collection duration ranged from 18 to 22 months, and approximately 1,600 water quality samples were collected. Significant (p < 0.1) inverse relationships were detected between peak flow response variables and both drainage area and fraction of forest cover. Order‐of‐magnitude differences in TP and dissolved reactive P (DRP) concentration were observed between AG and FORS sites and among AG sites. TP yields of FORS sites ranged from 0.01 to 0.1 kg P/ha. Yields of AG sites ranged from 0.031 to 3.17 kg P/ha (median = 0.354 kg P/ha). With 95% confidence intervals, AG yields ranged from 0.025 to 13.1 kg P/ha. These small‐watershed‐scale yields were similar to field‐scale yields measured in other studies in other regions. TP yields were significantly related to area‐weighted Mehlich‐1 soil test P concentrations (p = 0.0073) and base‐flow water sample P concentrations (p ≤ 0.0005). Water quality sampling during base‐flow conditions may be a useful screening tool for P risk‐based management programs. 相似文献
148.
149.
R Kent FJ Lopez-Valdes J Lamp S Lau D Parent J Kerrigan D Lessley R Salzar M Sochor D Bass MR Maltese 《Traffic injury prevention》2012,13(5):499-506
Objectives: This paper quantifies pediatric thoracoabdominal response to belt loading to guide the scaling of existing adult response data and to assess the validity of a juvenile porcine abdominal model for application to the development of physical and computational models of the human child. Methods: Table-top belt-loading experiments were performed on 6, 7, and 15 year-old pediatric post-mortem human subjects (PMHS). Response targets are reported for diagonal belt and distributed loading of the anterior thorax and for horizontal belt loading of the abdomen. Results: The pediatric PMHS exhibited abdominal response similar to the swine, including the degree of rate sensitivity. The thoraces of the PMHS were as stiff as, or slightly more stiff than, published adult corridors. Conclusions: An assessment of age-related changes in thoracic stiffness suggests that the effective stiffness of the chest increases through the fourth decade of life and then decreases, resulting in stiffness values similar for children and elderly adults. 相似文献
150.