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41.
We intend to estimate the value of ecosystem services in the U.S. State of New Jersey using spatially explicit benefit transfer. The aggregated net rent, a conservative underestimate for the total economic value of the state’s natural environment, ranged from 11.6 to11.6 to 19.6 billion/year, conditional on how inclusive we were in selecting the primary studies used to calculate the central tendency values to transfer. In addition to calculating the range, mean, and standard deviation for each of 12 ecosystem services for 11 Land Use/Land Cover (LULC) types, we also conduct a gap analysis of how well ecosystem service values are represented in the literature. We then map these values by assuming a mean value for each LULC and apply this to spatial data. As to sensitivity analysis, we calculate the net present value of New Jersey’s natural environment utilizing three different methods of discounting. These research results provide a useful, albeit imperfect, basis for assessing the value of ecosystem services and natural capital, and their comparison with the value of conventional human and built capitals.  相似文献   
42.
The release of nanosilver from consumer products used in the home   总被引:1,自引:0,他引:1  
Nanosilver has become one of the most widely used nanomaterials in consumer products because of its antimicrobial properties. Public concern over the potential adverse effects of nanosilver's environmental release has prompted discussion of federal regulation. In this paper, we assess several classes of consumer products for their silver content and potential to release nanosilver into water, air, or soil. Silver was quantified in a shirt, a medical mask and cloth, toothpaste, shampoo, detergent, a towel, a toy teddy bear, and two humidifiers. Silver concentrations ranged from 1.4 to 270,000 microg Ag g product(-1). Products were washed in 500 mL of tap water to assess the potential release of silver into aqueous environmental matrices (wastewater, surface water, saliva, etc.). Silver was released in quantities up to 45 microg Ag g product(-1), and size fractions were both larger and smaller than 100 nm. Scanning electron microscopy confirmed the presence of nanoparticle silver in most products as well as in the wash water samples. Four products were subjected to a toxicity characterization leaching procedure to assess the release of silver in a landfill. The medical cloth released an amount of silver comparable to the toxicity characterization limit. This paper presents methodologies that can be used to quantify and characterize silver and other nanomaterials in consumer products. The quantities of silver in consumer products can in turn be used to estimate real-world human and environmental exposure levels.  相似文献   
43.
Harshburger, Brian J., Karen S. Humes, Von P. Walden, Brandon C. Moore, Troy R. Blandford, and Albert Rango, 2010. Evaluation of Short-to-Medium Range Streamflow Forecasts Obtained Using an Enhanced Version of SRM. Journal of the American Water Resources Association (JAWRA) 46(3):603-617. DOI: 10.1111/j.1752-1688.2010.00437.x Abstract: As demand for water continues to escalate in the western United States, so does the need for accurate streamflow forecasts. Here, we describe a methodology for generating short-to-medium range (1 to 15 days) streamflow forecasts using an enhanced version of the Snowmelt Runoff Model (SRM), snow-covered area data derived from MODIS products, data from Snow Telemetry stations, and meteorological forecasts. The methodology was tested on three mid-elevation, snowmelt-dominated basins ranging in size from 1,600 to 3,500 km2. To optimize the model performance and aid in its operational implementation, two enhancements have been made to SRM: (1) the use of an antecedent temperature index method to track snowpack cold content, and (2) the use of both maximum and minimum critical temperatures to partition precipitation into rain, snow, or a mixture of rain and snow. The comparison of retrospective model simulations with observed streamflow shows that the enhancements significantly improve the model performance. Streamflow forecasts generated using the enhanced version of the model compare well with the observed streamflow for the earlier leadtimes; forecast performance diminishes with leadtime due to errors in the meteorological forecasts. The three basins modeled in this research are typical of many mid-elevation basins throughout the American West, thus there is potential for this methodology to be applied successfully to other mountainous basins.  相似文献   
44.
/ Several studies have suggested that use of wildernesses within national forests is declining. Data from three wildernesses in Oregon (based on mandatory permits and voluntary registration) indicate that between 1976 and 1991 in two areas and between 1980 and 1993 in another area the number of recreational visitor days (RVDs) has declined between 23% and 63%. However, the number of visits has remained roughly stable in one area and more than doubled in the other two. The disparity between the two measures of use may be the result of shifts from mainly overnight to mainly day use in these wildernesses. Day use has increased from about 30% to over 60% of all visits. Trends are different enough in each wilderness to warrant independent analyses over time. Management implications of using different measures of use as well as observed trends are discussed.KEY WORDS: Wilderness management; Wilderness use; Trends  相似文献   
45.
This study uses hedonic analysis to estimate the effects of flood hazard disclosure under the 1998 California Natural Hazard Disclosure Law (AB 1195) on property values throughout California. It finds that the average floodplain home sold for 4.2% less than a comparable non-floodplain home following AB 1195 while before that law there was no significant price differential. The introduction of interaction terms indicates that the magnitude of the price reduction due to AB 1195 varies positively with Hispanic population share. An average floodplain home in a half-Hispanic neighbourhood saw a $12 324 negative capitalization due to AB 1195, while that amount was only $2191 for a neighbourhood with 10% Hispanic residents. Results suggest that, in particular, homebuyers in Hispanic communities are better disclosed to under AB 1195 than they were under the National Flood Insurance Program (NFIP), which was the primary policy regulating flood disclosure in California prior to passage of AB 1195.  相似文献   
46.
Both males and females of many avian species maintain elaborate plumage traits, and elaborate monomorphic plumage may convey adaptive benefits to one or both sexes as inter- or intraspecific signals. Both sexes of the turquoise-browed motmot (Eumomota superciliosa) are elaborately plumed with long racket-tipped tail. I investigated whether the racketed tail functions as a sexually selected signal in one or both sexes by testing the predictions that males and/or females with the largest tails have: (1) greater pairing success, (2) greater reproductive performance (clutch-initiation date, clutch size, and hatching success), and (3) greater reproductive success. Yearling males with longer denuded rachises (wires) on the central tail feathers had greater pairing success. In addition, adult males with longer wires paired with females who laid larger clutches, had greater hatching success independent of clutch size, and fledged more young. There was no relationship between female tail plumage and pairing success, reproductive performance, or fledgling success. These results are consistent with the hypothesis that male tail plumage functions as a mate choice or status signal, but that the tail of the female does not function in a sexually selected context. I discuss alternative hypotheses for the evolutionary maintenance of the elaborate female tail plumage.  相似文献   
47.
Forecasting the likely economic losses arising from North Atlantic hurricanes is high on the agenda of both Caribbean and North American stakeholders. This paper develops a general equilibrium framework to conduct an impact assessment of climate change and hurricane formation. General equilibrium analysis accounts for not only primary effects but also feedback effects. The model simulations suggest that output losses occurring due to hurricanes are likely to have economy-wide effects. However, the rural economies of the region are likely to suffer the greatest (relative) effects. The findings of this study suggest that rural livelihoods should be mainstreamed in any adaptation initiatives adopted by the region. Ignoring these neighbourhood features in adaptation plans could negatively impact on poverty and unemployment in rural areas.  相似文献   
48.
Residual tetrachloroethene (PCE) contamination at the former Springvilla Dry Cleaners site in Springfield, Oregon, posed a potential risk through the vapor intrusion, direct contact, and off‐site beneficial groundwater uses. The Oregon Department of Environmental Quality utilized the State Dry Cleaner Program funds to help mitigate the risks posed by residual contamination. After delineation activities were complete, the source‐area soils were excavated and treated on‐site with ex situ vapor extraction to reduce disposal costs. Residual source‐area contamination was then chemically oxidized using sodium permanganate. Dissolved‐phase contamination was subsequently addressed with in situ enhanced reductive dechlorination (ERD). ERD achieved treatment goals across more than 4 million gallons of aquifer impacted with PCE concentrations up to 7,800 micrograms per liter prior to remedial activities. The ERD remedy introduced electron donors and nutrient amendments through groundwater recirculation and slug injection across two aquifers over the course of 24 months. Adaptive and mass‐targeted strategies reduced total remedy costs to approximately $18 per ton within the treatment areas. © 2010 Wiley Periodicals, Inc.  相似文献   
49.
Patterns of amenity migration and recreational home development in much of the USA since the 1990s are changing the local sociodemographic make-up and the relationships formed among people and place. We use the psychological constructs of place attachment, place identity, and place dependence to assess differences in these relationships among new and long-time residents and absentee and local residents in three rural counties in the Inland Northwest. We measured place bonding using data from a mail survey of local (n = 531) and absentee (n = 239) property owners. We compared structural models suggested in the literature on the psychology of place, and found that a two-dimensional model representing place attachment and place identity was appropriate for both local and absentee property owners. Local owners exhibited stronger place attachment and place identity than absentee owners. Place bonding constructs were also substantially less impacted by the total number of years a property owner had resided on his or her property than by the number of months per year they lived on the property. The findings indicate that sociodemographic changes such as those manifested in second-home development may lead to a population that is less emotionally, behaviorally, and cognitively connected to the places in question, while sociodemographic changes from permanent in-migration may have a substantially smaller effect on place bonding.  相似文献   
50.
Enhanced reductive bioremediation (ERB) of halogenated organics has become widely accepted and implemented to reduce risks to human health and the environment posed by these compounds. The family of chlorinated ethenes (e.g., trichloroethene) is among the most common contaminants treated using ERB techniques. The number of microbial species able to fully dechlorinate ethenes is small, and many times their population numbers are low. As a result, many ERB practitioners have turned to the injection of designer bacteria within treatment zones as a means to accelerate the process. Otherwise, many remediation projects encounter “cis‐stall,'' or the accumulation of the cis‐1,2‐dichloroethene and vinyl chloride intermediates. This article discusses three unique case studies where the addition of a balanced macro‐ and micro‐nutrient source substantially accelerated the chlorinated ethene ERB process, independent of the electron‐donor substrate applied. © 2013 Wiley Periodicals, Inc.  相似文献   
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