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371.
Thomas A. More James R. Averill Thomas H. Stevens 《Journal of environmental management》1996,48(4):397-409
Several categories of non-market value have been identified for forests and other natural environments: use value, option value, altruism, bequest value, existence value and intrinsic value. In this paper, we view these values from a psychological perspective. Non-market values arise because natural resources play important roles in furthering human goals. This goal perspective contrasts with intrinsic value—the idea that natural objects have value as ends in themselves regardless of their relationship to man. Because of the lack of precise definitions, elements of intrinsic value are often mixed with existence value, creating confusion in the literature. These resource values need to be examined on a logical as well as an empirical basis. We argue that careful scrutiny reveals problems with both existence value and intrinsic value so that it is important to question their role in policy formation and analysis. 相似文献
372.
Barry P Rochelle Donald L. Stevens M. Robbins. Church 《Journal of the American Water Resources Association》1989,25(3):491-498
ABSTRACT: The U.S. Environmental Protection Agency (EPA) in cooperation with the U.S. Geological Survey (USGS) conducted an analysis to quantify the uncertainty associated with interpolating runoff to specific sites using a runoff contour map. We interpolated runoff to 93 gaged watersheds from a runoff contour map using (1) hand interpolation to the watershed outlet, (2) a computer interpolation to the watershed outlet, and (3) hand interpolation to the watershed centroid. We compared the interpolated values to the actual gaged values and found that there was a bias in the average interpolated value for runoff estimated at basin outlets, with interpolated values being less than the actual. We found no significant difference between the hand interpolation method and the computer interpolation method except that the computer method tended to have higher variability due to factors inherent to the software used. There were no strong spatial correlations or regional patterns in the runoff interpolations, which indicates that there are no regional biases introduced in the development of the contour map. We determined that we could estimate runoff, on the average, within approximately 8.9 cm (3.5 in; 15 percent) of the measured value using the three methods. The results of this work indicate that runoff contour maps can he used in regional studies to estimate runoff to ungaged systems with quantifiable uncertainty. 相似文献
373.
Christine Vanessa Schmidt Sabine Frohschammer Alexandra Schrempf Jürgen Heinze 《Die Naturwissenschaften》2014,101(1):69-72
Mother–son mating (oedipal mating) is practically non-existent in social Hymenoptera, as queens typically avoid inbreeding, mate only early in life and do not mate again after having begun to lay eggs. In the ant genus Cardiocondyla mating occurs among sib in the natal nests. Sex ratios are extremely female-biased and young queens face the risk of remaining without mating partners. Here, we show that virgin queens of Cardiocondyla argyrotricha produce sons from their own unfertilized eggs and later mate with them to produce female offspring from fertilized eggs. Oedipal mating may allow C. argyrotricha queens to found new colonies when no mating partners are available and thus maintains their unusual life history combining monogyny, mating in the nest, and low male production. Our result indicates that a trait that sporadically occurs in solitary haplodiploid animals may evolve also in social Hymenoptera under appropriate ecological and social conditions. 相似文献
374.
375.
Alexandra T. Gruia Camelia Oprean Alexandra Ivan Ada Cean Mirabela Cristea Lavinia Draghia Roxana Damiescu Nikola M. Pavlovic Virgil Paunescu Calin A. Tatu 《Environmental geochemistry and health》2018,40(4):1437-1448
Aristolochic acids (AAs) are carcinogenic and nephrotoxic plant alkaloids present in Aristolochia species, used in traditional medicine. Recent biomolecular and environmental studies have incriminated these toxins as an etiological agent in Balkan endemic nephropathy (BEN), a severe kidney disease occurring in the Balkan Peninsula. The questions on how the susceptible populations are exposed to these toxins have not yet been clearly answered. Exposure to AAs through the food chain, and environmental pollution (soil/dust), could provide an explanation for the presence of BEN in the countries where no folkloric use of the plant has been documented (Bulgaria, Croatia). Additional exposure pathways are likely to occur, and we have shown previously that AAs can contaminate crop plants through absorption from soil, under controlled laboratory environment. Here, we attempt to provide additional support to this potential exposure pathway, by revealing the presence of AAI in soil and soil organic matter samples collected from BEN and non-BEN areas. The samples were processed in order to be analyzed by high-pressure liquid chromatography, and ion trap mass spectrometry. Our results showed the presence of AAI in small concentrations, both in BEN and non-BEN soils, especially where Aristolochia plants and seeds were present. 相似文献
376.
Alexandra Spodar Arnaud Héquette Marie-Hélène Ruz Adrien Cartier Pascal Grégoire Vincent Sipka Nicolas Forain 《Journal of Coastal Conservation》2018,22(3):457-474
The largest beach replenishment project ever in France was completed in February 2014 in Dunkirk on the coast of northern France. A volume of 1.5 × 106 m3 of sand extracted from a navigation channel was placed on the beach to build up a 150 to 300 m wide supratidal platform in front of a dike, called « Digue des Alliés », which protects several residential districts of Dunkirk from marine flooding. High resolution topographic surveys were carried out during 2½ years to monitor beach morphological changes, completed by a hydrodynamic field experiment conducted in February 2016. Approximately ?138,200 m3 of sand, corresponding to 9.2% of the initial nourishment volume, were eroded over the nourishment area in about 2 years. An obvious decrease in erosion eastward with a shift from erosion to accumulation was observed, suggesting an eastward redistribution of sand. This longshore sand drift is beneficial for the eastward beach of Malo-les-Bains where most of the recreational activities are concentrated. Hydrodynamic measurements showed that waves and wave-induced currents play a major role on the longshore sand redistribution compared to tidal flows. Strong relationships were observed between cumulative offshore wave power and beach volume change during distinct beach survey periods (R2 = 0.79 to 0.87), with more significant correlations for northerly waves. A slight decrease in erosion during the second year compared to the first year after nourishment suggests that the loss of sand should decrease after an initial phase of rapid readjustment of the beach shape towards equilibrium. 相似文献
377.
Conservation practitioners widely recognize the importance of making decisions based on the best available evidence. However, the effectiveness of evidence use in conservation planning is rarely assessed, which limits opportunities to improve evidence-based practice. We devised a mixed methodology for empirically evaluating use of evidence that applies social science tools to systematically appraise what kinds of evidence are used in conservation planning, to what effect, and under what limitations. We applied our approach in a case study of the Nature Conservancy of Canada (NCC), a leading land conservation organization. We conducted qualitative and quantitative analyses of 65 NCC planning documents (n = 13 in-depth) to identify patterns in evidence use, and surveyed 35 conservation planners to examine experiences of and barriers to using evidence. Although claims in plans contained a wide range of evidence types, 26% of claims were not referenced or associated with an identifiable source. Lack of evidence use was particularly apparent in claims associated with direct threats, particularly those identified as low (71% coded as insufficient or lacking evidence) or medium (45%) threats. Survey participants described relying heavily on practitioner experience and highlighted capacity limitations and disciplinary gaps in expertise among planning teams as barriers to using evidence effectively. We found that although time-intensive, this approach yielded actionable recommendations for improving evidence use in NCC conservation plans. Similar mixed-method assessments may streamline the process by including interviews and refining the document analysis frames to target issues or sections of concern. We suggest our method provides an accessible and robust point of departure for conservation practitioners to evaluate whether the use of conservation planning reflects in-house standards and more broadly recognized best practices. 相似文献
378.
Consolazio Nizette Hakala J. Alexandra Lowry Gregory V. Karamalidis Athanasios K. 《Environmental Chemistry Letters》2022,20(1):773-795
Environmental Chemistry Letters - Biocides are applied as chemical additives in hydraulic fracturing fluids to control subsurface microbial activity. When biocides are released into the subsurface,... 相似文献
379.
Nicholas E. Williams Seeta A. Sistla Daniel B. Kramer Kara J. Stevens Adam B. Roddy 《Conservation biology》2022,36(1):e13784
Coastal zones, which connect terrestrial and aquatic ecosystems, are among the most resource-rich regions globally and home to nearly 40% of the global human population. Because human land-based activities can alter natural processes in ways that affect adjacent aquatic ecosystems, land-sea interactions are increasingly recognized as critical to coastal conservation planning and governance. However, the complex socioeconomic dynamics inherent in coastal and marine socioecological systems (SESs) have received little consideration. Drawing on knowledge generalized from long-term studies in Caribbean Nicaragua, we devised a conceptual framework that clarifies the multiple ways socioeconomically driven behavior can link the land and sea. In addition to other ecosystem effects, the framework illustrates how feedbacks resulting from changes to aquatic resources can influence terrestrial resource management decisions and land uses. We assessed the framework by applying it to empirical studies from a variety of coastal SESs. The results suggest its broad applicability and highlighted the paucity of research that explicitly investigates the effects of human behavior on coastal SES dynamics. We encourage researchers and policy makers to consider direct, indirect, and bidirectional cross-ecosystem links that move beyond traditionally recognized land-to-sea processes. 相似文献
380.
Chatzikonstantinou Alexandra V. Giannakopoulou Αrchontoula Spyrou Stamatia Simos Yannis V. Kontogianni Vassiliki G. Peschos Dimitrios Katapodis Petros Polydera Angeliki C. Stamatis Haralambos 《Environmental science and pollution research international》2022,29(20):29624-29637
Environmental Science and Pollution Research - As olive leaves constitute the main by-product of the olive oil industry with important environmental and economic impact, there is an increasing... 相似文献