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51.
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Agri-environmental measures are payments to farmers to reduce environmental risks or to preserve cultivated landscapes. These measures are codified in European Union regulations. Poor spatial targeting is one of the major causes of low cost-effectiveness in agri-environmental measures. Existing studies on spatial targeting focus primarily on selected individual measures; hence, they do not allow for conclusions at the program level, where the planning and implementing of decisions on a number of different measures has to be made. In this study, we analyzed the impacts of two spatial targeting options (targeting of erosion-reducing measures on erosion vulnerable areas; targeting of grassland extensification on N-pollution vulnerable areas) on the cost-effectiveness of the single measures and the entire agri-environmental program of the federal state of Brandenburg in Germany. The methodological steps included an analysis of empirical data on land use and program participation, an expert-based environmental impact assessment and a spatial allocation procedure based on linear programming. The environmental impact assessment delivered goal-specific index values for each measures-land parcel combination expressing the suitability of the measures for contributing to four regionally relevant program objectives. The cost-effectiveness of the measures and the program were calculated by putting budgetary costs in relation to the achieved environmental index sum. The calculated cost-effectiveness of the program in 2006 was 89.6% of the simulated optimal cost-effectiveness. The spatial targeting of erosion-reducing measures on erosion vulnerable areas caused an increase in the cost-effectiveness at the measures level and almost no changes at the program level. The spatial targeting of grassland extensification on N-pollution vulnerable areas, despite also improving the cost-effectiveness of this measure, had negative effects on the cost-effectiveness of the program.  相似文献   
53.
Accumulation of cadmium in periphyton was investigated under field conditions while Cd concentration and speciation were dynamically varying in a small stream during rain events. Speciation in water was determined in situ by diffusion gradient in thin-films (DGT) and by modeling of complexation with fulvic acids. During the rain events, dissolved Cd concentrations increased from 0.17 nM to 0.27-0.36 nM, and 70-97% were DGT-labile. Cd content in periphyton closely followed Cd concentrations in water, despite higher concentrations of Zn and Mn, and may be controlled by either free or DGT-labile Cd concentrations. Decrease of Cd content in periphyton after the rain events was slower than the decrease of Cd concentration in water. Concentrations of Zn, Mn, Cu, Pb and Fe in periphyton also followed the dynamic variations of metal concentrations in water. Repeated exposure of periphyton to elevated dissolved Cd may lead to Cd accumulation.  相似文献   
54.
Zödl B  Wittmann KJ 《Chemosphere》2003,52(7):1095-1103
In order to obtain basic information for designing standardized test preparation methods, the heavy metals Zn, Cu, Cd and Pb were measured in gastropods (Xerolenta obvia), oligochaetes (Lumbricus terrestris), isopods (Armadillidium vulgare, Trachelipus rathkei) and carabids (Harpalus rubripes, Calathus fuscipes) using different sampling methods and different modes of sample treatment. In some of the experiments, higher Zn, Cd and Pb, and lower Cu-contents were observed in isopods and carabids trapped with formalin-pitfalls compared to manually collected specimens (which were allowed to defecate). Defecation had marked effects on the levels of all four metals investigated in oligochaetes, and on Cd and Pb in gastropods and isopods. Cellulose was fed as an accelerator of gut passage and showed a significant effect on the Pb concentration in the soft body of gastropods. Deionate-washed isopods (A. vulgare) showed higher Cd concentrations than ultrasonic-cleaned individuals. No marked differences were observed between heat-dried and freeze-dried isopods. Carabids showed strong sex-specific differences in metal concentrations. Based on these and previous results, invertebrates should be: collected in vivo, allowed to defecate, be freeze-fixed and (at least in arthropods) ultrasonic-cleaned, determined to species level and in certain groups (carabids) also to sex, and then be sized or sorted by size (age) before further preparation and analysis. If any of these treatments is impractical, comparable sampling and preparation methods are recommended as a minimum requirement in order to avoid bias in the results and/or interpretation.  相似文献   
55.
ABSTRACT: The resource management problem for the Middle Platte ecosystem is the insufficient water available to meet both instream ecological demands and out‐of‐stream economic needs. This problem of multiple interest groups competing for a limited resource is compounded by sharp disagreement in the scientific community over endangered species' needs for instream flows. In this study, game theory was used to address one dimension of this resource management problem. A sequential auction with repeated bidding was used to determine how much instream flow water each of three states — Colorado, Nebraska, and Wyoming — will provide and at what price. The results suggest that the use of auction mechanisms can improve the prospects for reaching a multi‐state agreement on who will supply instream flow water, if the auction is structured to discourage misrepresentation of costs and if political compensation is allowed.  相似文献   
56.
Going beyond the relation of work and family, the present three‐wave longitudinal study spanning one year assessed different forms of conflict and facilitation between leisure and the life domains work and family and their relation to subjective well‐being. A sample of N = 277 employed men and women reported their perceived conflict and facilitation between leisure, work, and family and subjective well‐being. Results suggest that leisure is a source of facilitation for work and family, and, at the same time, a major recipient of conflict from work and family. Moreover, leisure conflict was negatively correlated and leisure facilitation was positively associated with concurrent subjective well‐being. Both conflict and facilitation between all three life domains remained highly stable over the course of one year. Only few and non‐systematic lagged effects were found, indicating that the variance of the stability of the constructs and their relations over time leave little room for longitudinal predictions. Taken together, the study demonstrates that, similar to work–family relations, conflict and facilitation with the leisure domain are also associated with subjective well‐being and remain highly stable over the course of a year in the lives of young and middle‐aged adults. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
57.
Strains ofPseudomonas putida, Ps. fluorescens, Arthrobacter hydrocarboglutamicus andNocardia sp. tolerateo-nitroaniline andp-nitrophenol in concentrations up to 50 ppm without growth inhibition. Total growth inhibition occurs at concentrations of 200 ppm and more. OnlyNocardia sp. can transform both compounds, to a certain extent. The two metabolites 4-hydroxy-2-nitroaniline and 4-nitrobrenzcatechol are not further degraded by this organism.  相似文献   
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59.
Ultrasound examination of a 27-year-old primigravida at 26 weeks' gestation revealed fetal growth retardation, malformation of the ventricular septum, and a neck fold. Chromosome analysis of the amniotic fluid showed an abnormal 46,XY karyotype with an obvious meta-centric chromosome 17. Chromosome analysis of the mother revealed a balanced t (17;22) (p13;q12) translocation. The fetus thus has a rare familial duplication 22q12→qter. Eight live-born and severely malformed infants with this duplication have been reported in the literature.  相似文献   
60.
Based on a “whole-life”-perspective and integrating theories of self-identity and resource management, the present longitudinal study examines the dynamic relationship between career involvement and conflicts between work and nonwork goals in a sample of 3095 German-speaking doctoral students and doctorate holders (37.0% women) from various STEM fields. We expected increases in goal conflicts to decrease career involvement, and simultaneously tested reciprocal relationships, that is, from involvement on conflicts. The random intercept cross-lagged panel model (RI-CLPM) was used to analyze within-person associations across eight measurement occasions (6-month time intervals) while controlling for between-person effects. At the between-person level, career involvement and goal conflicts were negatively correlated. At the within-person level, results showed negative cross-lagged effects from goal conflicts to career involvement as well as negative cross-lagged effects from career involvement to goal conflicts. This indicates that the interplay of goal conflicts and career involvement can result in either an upward or a downward spiral. Theoretical and practical implications are discussed.  相似文献   
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