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151.
A quantitative analysis is presented of not only the direct but also of the indirect effects resulting from the fact that waste in any one part of a nation's industrial structure also induces waste in other parts.  相似文献   
152.
153.
Soil fumigation using shank injection creates high fumigant concentration gradients in soil from the injection point to the soil surface. A temperature gradient also exists along the soil profile. We studied the degradation of methyl isothiocyanate (MITC) and 1,3-dichloropropene (1,3-D) in an Arlington sandy loam (coarse-loamy, mixed, thermic Haplic Durixeralf) at four temperatures and four initial concentrations. We then tested the applicability of first-order, half-order, and second-order kinetics, and the Michaelis-Menten model for describing fumigant degradation as affected by temperature and initial concentration. Overall, none of the models adequately described the degradation of MITC and 1,3-D isomers over the range of the initial concentrations. First-order and half-order kinetics adequately described the degradation of MITC and 1,3-D isomers at each initial concentration, with the correlation coefficients greater than 0.78 (r2> 0.78). However, the derived rate constant was dependent on the initial concentration. The first-order rate constants varied between 6 and 10x for MITC for the concentration range of 3 to 140 mg kg(-1), and between 1.5 and 4x for 1,3-D isomers for the concentration range of 0.6 to 60 mg kg(-1), depending on temperature. For the same initial concentration range, the variation in the half-order rate constants was between 1.4 and 1.7x for MITC and between 3.1 and 6.1x for 1,3-D isomers, depending on temperature. Second-order kinetics and the Michaelis-Menten model did not satisfactorily describe the degradation at all initial concentrations. The degradation of MITC and 1,3-D was primarily biodegradation, which was affected by temperature between 20 and 40 degrees C, following the Arrhenius equation (r2 > 0.74).  相似文献   
154.
This study of a random sample of self-employed and non-self-employed dentists tests the French, Rodgers, and Cobb (1974) hypothesis, which predicts a curvilinear relationship between psychological strain and person-environment fit. Self-employed dentists had lower strain scores (based on measures of job satisfaction and self-esteem) and greater congruency in P-E fit (based on comparisons of preferred and typical hours in practice) than dentists who were not self-employed. The relationship between strain and P-E fit among self-employed dentists was curvilinear. Both self-esteem and job satisfaction were higher for dentists with a congruent fit between typical and preferred workload and lower for dentists with incongruent fit.  相似文献   
155.
This paper attempts to measure, in a cost-benefit analysis, a stricter noise abatement programme for noise originating from roads in Israel. Using the hedonic price method for three large cities and rural area transactions, a benefit from noise reduction was found. In order to perform a social cost-benefit analysis, a measure of benefit has been derived for 1 km of road and has been compared with the cost of noise reduction under different types of road structure. The results indicate that even though benefits have largely increased when compared to past decades (e.g. 1.2% of an average urban property value per 1 decibel reduction), the decision to insulate a given road is dependent on location and road structure. This raises the normative question of a national vs. regional standard that decision makers should be aware of and such studies could be of help in this respect.  相似文献   
156.
Mosquitoes and mosquito-borne diseases know no borders, and their spread is a consequence of globalization related to high mobility of humans and international trade as well as on climate change. Higher temperatures and precipitation favour the development of mosquitoes as well as the pathogens and parasites which are transmitted by mosquitoes. An increase of about 2?°C would shorten the time for the development of larvae and pupae of Anopheles messeae (vector of malaria) by almost three days resulting in an increase of gonotrophic cycles and number of generations. The higher numbers of breeding sites for Anopheles species such as An. plumbeus in cess pools due to the change of agricultural practises increase the contact with potential vectors of malaria as well. However, at least in Germany, malaria will not play an important role anymore. The invasion of new species such as Stegomyia albopicta (formerly Aedes albopictus) is enhanced by human migration and international trade. St. albopicta was first discovered in Germany in 2007. Nowadays, this species, originally from Southeast Asia, occurs in 13 European states. Thus, the risk for outbreaks of arboviroses is increased.  相似文献   
157.
Gull eggs have been used to monitor contaminants in many parts of the world. The Seabird Tissue Archival and Monitoring Project (STAMP) is a long-term program designed to track trends in pollutants in northern marine environments using seabird eggs. Glaucous and glaucous-winged gull (Larus hyperboreus and Larus glaucescens) eggs collected in 2005 from seven Alaskan colonies were analyzed for organic contaminants. Concentrations ranged from below detection limits to 322 ng g−1 wet mass in one egg for 4,4′-DDE and differed among the samples collected in the Gulf of Alaska and Bering and Chukchi Seas. Chick growth and survival rates may be affected by the contaminant levels found in the eggs, but the eggs should be safe for human consumption if they are eaten in small quantities. STAMP plans to continue collecting and banking gull eggs for future real-time and retrospective analyses.  相似文献   
158.
Mobile coastal dunes are of significant ecological importance both globally and locally. Yet a large portion of these dunes are disappearing due to encroachment of local shrubs and exotic plants, resulting in changes of floristic and faunal composition, and an overall decrease in biodiversity of coastal systems. Active management is therefore required to maintain mobile dune presence. This study focuses on economic valuation of coastal dunes in Israel, based on public and professional ecological perspectives. This comparison allows reflection on the suitability of a contingent valuation method (CVM) to assess ecological restoration and conservation projects. The CVM was applied in Nizzanim LTER nature reserve in Israel, and concurrently, data of plant species composition on stabilized and mobile dunes were used to calculate the ecological value index (EVI) of the different dune states. The EVI was then transformed into monetary terms by combining the public valuation and the relative proportion of the various species to the total coverage. The monetary values derived from the general public and the ecological assessment were then compared and used to estimate the expected change in economic value resulting from a state shift from mobile to stabilized dunes. According to the CVM, the total value of the Nizzanim coastal dunes would drop from 344 to 197 million Israeli Shekels (NIS) (1 Shekel = $0.39) if active management does not take place, a reduction of 42 % in value. However, results from the EVI indicate only a 33 % decrease in ecological value (in monetary terms) in the absence of active management. We suggest that in this case, general public perception is strong enough to justify conservation decisions, even though they are not professional ecologists. However, we still recommend the use of both measures for land use decision making.  相似文献   
159.
In the 35 years since its inception, the Brazilian National Program for the Conservation of Marine Turtles (TAMAR) has had great success in protecting the five species of sea turtles that occur in Brazil. It has also contributed significantly to worldwide scientific data and knowledge about these species’ biology, such as life cycles and migration patterns. TAMAR’s conservation strategies have always relied on a variety of environmental education and social inclusion (EESI) activities highly adapted to the socio-environmental evolving contexts of its 25 locations distributed across nine states. Diversity and flexibility are critical to enable timely and effective local responses to existing or potential threats to sea turtles. The intuitive, locally adapted, decentralized, and independent way EESI activities have been carried out have generated positive results in the resolution of specific and evolving local problems through the course of the project. This article brings EESI under the same conceptual framework that underlies its conservation approach by adopting an adaptive threat management framework to organize and qualify its educational and social inclusion interventions according to the main categories of threat addressed by TAMAR.  相似文献   
160.
Participatory processes for obtaining residents' input about community impacts of proposed environmental management actions have long raised concerns about who participates in public involvement efforts and whose interests they represent. This study explored methods of broad-based involvement and the role of deliberation in social impact assessment. Interactive community forums were conducted in 27 communities to solicit public input on proposed alternatives for recovering wild salmon in the Pacific Northwest US. Individuals identified by fellow residents as most active and involved in community affairs ("AE residents") were invited to participate in deliberations about likely social impacts of proposed engineering and ecological actions such as dam removal. Judgments of these AE participants about community impacts were compared with the judgments of residents motivated to attend a forum out of personal interest, who were designated as self-selected ("SS") participants. While the magnitude of impacts rated by SS participants across all communities differed significantly from AE participants' ratings, in-depth analysis of results from two community case studies found that both AE and SS participants identified a large and diverse set of unique impacts, as well as many of the same kinds of impacts. Thus, inclusion of both kinds of residents resulted in a greater range of impacts for consideration in the environmental impact study. The case study results also found that the extent to which similar kinds of impacts are specified by AE and SS group members can differ by type of community. Study results caution against simplistic conclusions drawn from this approach to community-wide public participation. Nonetheless, the results affirm that deliberative methods for community-based impact assessment involving both AE and SS residents can provide a more complete picture of perceived impacts of proposed restoration activities.  相似文献   
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