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291.
Individuals of Mytilus edulis L., collected from the Erme estuary (S.W. England) in 1978, were exposed to low concentrations (7 to 68 g l-1) of the water-accommodated fraction (WAF) of North Sea crude oil. The pattern of accumulation of petroleum hydrocarbons in the body tissues was affected by the presence of algal food cells, the period of exposure, the hydrocarbon concentration in seawater, the type of body tissue and the nature of the hydrocarbon. Many physiological responses (e.g. rates of oxygen consumption, feeding, excretion, and scope for growth), cellular responses (e.g. lysosomal latency and digestive cell size) and biochemical responses (e.g. specific activities of several enzymes) were significantly altered by short-term (4 wk) and/or long-term (5 mo) exposure to WAF. Stress indices such as scope for growth and lysosomal latency were negatively correlated with tissue aromatic hydrocarbons.  相似文献   
292.
Summary Adult male tree lizards, Urosaurus ornatus, practise alternative (territorial or sneaker/satellite) reproductive strategies that are correlated with differences in throat color and body size. In this study we raised tree lizards from hatching in the laboratory to examine the question of whether the phenotypic expression of secondary sex coloration and body size can be facultatively influenced by social or abiotic environmental factors. We compared males reared in the laboratory under different social and environmental conditions to males in the field and found no effect of different conditions on phenotypic differentiation (Figs. 2–4). Thus, phenotypic differences between morphs probably result largely from nonfacultative expression of different genotypes. This suggests that alternative male morphs practise a mixed evolutionary stable strategy (ESS) rather than one morph making the best of a bad situation. However, in the context of ESS theory it is difficult to explain our further result that the nonterritorial morph in this species grows faster and reaches a larger adult body size than the territorial morph (Fig. 5).  相似文献   
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Environmental psychology is a field of such great diversity—in topics of interest, research approaches, in disciplinarity—that it often appears to lack coherence, exemplified by its poor fit within paradigmatic frameworks found in academic psychology, resulting in its “outlier” status. This paper explores the work of the environmental gerontologist M. Powell Lawton, as an exemplar of environmental psychology research, suggesting that such a review renders greater insight into the current state of the field than any top-down applied conceptual framework. Themes discussed include Lawton's theoretical perspective on the person, the environment, and the relationship between them, his inquiry at various units of analysis; the type of knowledge valued as evidenced in his work; and his fundamental applied orientation, all of which are reflective of contemporary directions within environmental psychology as a whole. Reviewed is Lawton's final proposal that takes an “epistemologically inclusive” approach, embodying all of the themes above and reflective of inquiry sought within pragmatic psychology. As such, it is argued that environmental psychology may find great affinity with the pragmatic psychology approach currently gaining impetus within applied and clinical psychology.  相似文献   
296.
The negative effects of unemployment on psychological health are well documented, yet Kasl's ( 1982 ) reverse causation hypothesis is that positive psychological health, and in particular self‐esteem, facilitates re‐employment. The aim of this study was to investigate this proposal by assessing levels of self‐esteem, cognitive appraisals and coping efforts among unemployed persons and relating these factors to their employment status six months later. Two hundred and one unemployed (49 per cent female, 51 per cent male; mean age = 32.41 ± 10.18 years) and 128 employed respondents (59 per cent female, 41 per cent male; mean age = 35.0 ± 11.73 years) participated in the study. Participants completed the Adult Self‐Perception Profile, Access to Categories of Experience, Locus of Control, Deakin Coping Scale, and the Meaningful Leisure Activities Questionnaire at baseline and at six‐month follow‐up using a mail‐out survey. Comparison of baseline appraisals revealed that future re‐employed participants rated their latent deprivation lower and their internal locus of control higher than those continuously unemployed, and they also derived more internal meaning from leisure activities. Overall, the results provide support for Kasl's reverse causation hypothesis extended to these other domains of psychological health. Intervention strategies designed to incorporate the promotion of these factors are discussed. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
297.
Macroalgal fields are a feature of the shallow tropical benthos, yet their importance for coral reef fish population dynamics remains poorly understood. The abundance of fish recruits was recorded using underwater visual census at six macroalgal and 11 coral reef sites in the Montebello and Barrow Islands. Surveys identified 6,935 individual recruit fish from 105 species, 54 genera and 20 families. Of these, 1,401 recruits from 48 species, 31 genera and 14 families were observed in macroalgal sites. Sixteen of the 105 recruit species (15.2 %) were observed exclusively at macroalgal sites. Forty-two (87.5 %) of these species have been observed as adults on adjacent coral reefs. Species composition of fish recruits differed significantly between the two habitats. Corallivore, small omnivore and zooplanktivore recruits had significantly higher numbers in the coral sites, while the results clearly demonstrate that juveniles, within the genera Lethrinus and Choerodon, as well as large algal croppers, are predominantly found at macroalgal (74–100 %) rather than coral-dominated sites. High-canopy macroalgae cover was positively correlated with abundance of these taxa, particularly Lethrinids (r 2 = 0.40). This study is the first to highlight the important attributes of tropical macroalgal fields and suggests that they have a similar role to seagrass meadows as essential juvenile habitat, thus warranting greater attention in conservation planning and ecological studies.  相似文献   
298.
Addressing environmental problems requires sophisticated approaches to complexity and uncertainty. Conceptual models are increasingly used to improve understanding of complex system interactions. However, cursory treatment of governance limits their analytical potential. This study included governance considerations in a social-ecological system model of biodiversity conservation in the Tasmanian Midlands (Australia). Effectiveness of engagement processes and conservation programme longevity were identified as critical governance influences. The conceptual representation of this system enabled exploration of how governance influences interact with social drivers (e.g. landholder engagement in conservation practices) to modify the effect of biophysical drivers (e.g. land use) on biodiversity outcomes. Such a methodology provides essential information for identifying and guiding governance related points of intervention.  相似文献   
299.
Hydraulically connected wetland microcosms (~50?L) in series were used to test the effectiveness of varying combinations of two common aquatic vascular plants, parrot feather (Myriophyllum aquaticum) and cattail (Typha latifolia), for mitigating contamination from a mixture of nitrogen (ammonium nitrate) and permethrin. The upstream series included Myriophyllum only (M) and Typha only (T) while the combination upstream effluent into downstream series included Myriophyllum into Myriophyllum (M?+?M) and Typha into Myriophyllum (T?+?M). During flow, M into M?+?M more efficiently mitigated nitrogen than T into T?+?M. Post-flow, nitrogen removal efficiency was greater for T versus M and M?+?M versus T?+?M. Mean aqueous dissipation half-lives (t1/2) of NH4-N and NO3-N were more rapid in T than M treatments. Ammonium and nitrate t1/2 was highly correlated with aquatic plant above-ground shoot biomass. Permethrin mitigation efficiencies and t1/2 were not significantly affected by plant species either singly or in combination. Trans-permethrin t1/2 was moderately correlated with plant biomass, but not cis-permethrin t1/2. Results of this study indicate differences in aquatic plant species and flow path influence nitrogen removal but not permethrin. However, plant species appears less important than overall plant biomass in ascertaining aquatic plant effectiveness in mitigating a nitrogen–permethrin mixture.  相似文献   
300.
More than half a decade has passed since the December 26th 2004 tsunami hit the Indian coast leaving a trail of ecological, economic and human destruction in its wake. We reviewed the coastal ecological research carried out in India in the light of the tsunami. In addition, we also briefly reviewed the ecological research in other tsunami affected countries in Asia namely Sri Lanka, Indonesia, Thailand and Maldives in order to provide a broader perspective of ecological research after tsunami. A basic search in ISI Web of Knowledge using keywords “tsunami” and “India” resulted in 127 peer reviewed journal articles, of which 39 articles were pertaining to ecological sciences. In comparison, Sri Lanka, Indonesia, Thailand and Maldives had, respectively, eight, four, 21 and two articles pertaining to ecology. In India, bioshields received the major share of scientific interest (14 out of 39) while only one study (each) was dedicated to corals, seagrasses, seaweeds and meiofauna, pointing to the paucity of research attention dedicated to these critical ecosystems. We noted that very few interdisciplinary studies looked at linkages between pure/applied sciences and the social sciences in India. In addition, there appears to be little correlation between the limited research that was done and its influence on policy in India. This review points to gap areas in ecological research in India and highlights the lessons learnt from research in other tsunami-affected countries. It also provides guidance on the links between science and policy that are required for effective coastal zone management.  相似文献   
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