Studies that incorporate information from habitat-specific ecological interactions (e.g., epibiotic associations) can reveal valuable insights into the cryptic habitat-use patterns and behavior of marine vertebrates. Sea turtles, like other large, highly mobile marine vertebrates, are inherently difficult to study, and such information can inform the implementation of conservation measures. The presence of epipelagic epibionts, such as the flotsam crab Planes major, on sea turtles strongly suggests that neritic turtles have recently occupied epipelagic habitats (upper 200 m in areas with >200 m depth) and that epipelagic turtles spend time at or near the surface. We quantified the effects of turtle species, turtle size, and habitat (neritic or epipelagic) on the frequency of epibiosis (F0) by P. major on sea turtles in the Pacific Ocean. In neritic habitats, we found that loggerhead (F0 = 27.6 %) and olive ridley turtles (F0 = 26.2 %) host crabs frequently across a wide range of body sizes, and green turtles almost never host crabs (F0 = 0.7 %). These results suggest that loggerheads and olive ridleys display variable/flexible epipelagic-neritic transitions, while green turtles tend to transition unidirectionally at small body sizes. In epipelagic habitats, we found that loggerheads host crabs (F0 = 92.9 %) more frequently than olive ridleys (F0 = 50 %) and green turtles (F0 = 38.5 %). These results suggest that epipelagic loggerheads tend to spend more time at or near the surface than epipelagic olive ridleys and green turtles. Results of this study reveal new insights into habitat-use patterns and behavior of sea turtles and display how epibiont data can supplement data from more advanced technologies to gain a better understanding of the ecology of marine vertebrates during cryptic life stages. 相似文献
River systems are increasingly under stress and pressure from agriculture and urbanization in riparian zones, resulting in frequent engineering interventions such as bank stabilization or flood protection. This study provides guidelines for a more sustainable approach to river management based on hydrogeomorphology concepts applied to three contrasted rivers in Quebec (Canada). Mobility and flooding spaces are determined for the three rivers, and three levels of “freedom space” are subsequently defined based on the combination of the two spaces. The first level of freedom space includes very frequently flooded and highly mobile zones over the next 50 years, as well as riparian wetlands. It provides the minimum space for both fluvial and ecological functionality of the river system. On average for the three studied sites, this minimum space was approximately 1.7 times the channel width, but this minimum space corresponds to a highly variable width which must be determined from a thorough hydrogeomorphic assessment and cannot be predicted using a representative average. The second level includes space for floods of larger magnitude and provides for meanders to migrate freely over a longer time period. The last level of freedom space represents exceptional flood zones. We propose the freedom space concept to be implemented in current river management legislation because it promotes a sustainable way to manage river systems, and it increases their resilience to climate and land use changes in comparison with traditional river management approaches which are based on frequent and spatially restricted interventions. 相似文献
Variation in physical factors, such as slope, orientation, and wind exposure, shapes thermal conditions. Variation in substrate size is common in many habitats, but its thermal consequences for organisms are not well characterized. Larger substrates should remain more thermally stable and act as thermal refuges for associated organisms during short, thermally stressful periods such as midday temperature peaks or tidal exposure. In observations and a transplant and thermal integration experiment, we found that larger rock substrates stayed cooler and facilitated greater survival of the barnacle Semibalanus balanoides in the high intertidal relative to small substrates during the hot summer months in southern New England, USA. However, in thermally benign northern New England, rock substrate size had no effect on barnacle distributions, indicating that the thermal effects of substrate size are mediated by regional climate. 相似文献
Health status depends on multiple genetic and non-genetic factors. Nonheritable factors (such as lifestyle and environmental factors) have stronger impact on immune responses than genetic factors. Firefighters work is associated with exposure to air pollution and heat stress, as well as: extreme physical effort, mental stress, or a changed circadian rhythm, among others. All these factors can contribute to both, short-term and long-term impairment of the physical and mental health of firefighters. Increased levels of some inflammatory markers, such as pro-inflammatory cytokines or C-reactive protein (CRP) have been observed in firefighters, which can lead to local, acute inflammation that promotes a systemic inflammatory response. It is worth emphasizing that inflammation is one of the main hallmarks of cancer and also plays a key role in the development of cardiovascular and respiratory diseases. This article presents possible causes of the development of an inflammatory reaction in firefighters, with particular emphasis on airway inflammation caused by smoke exposure.
Environmental impact assessment (EIA) has been required for certain proposed road developmentsin the UK since EC Directive (85/337) was implemented in 1988. The extent to which the requirements of the EIA Directive are met with respect to ecological issues has been explored in earlier reviews of road statements (Treweek et al., 1993) and of UK environmental impact statements (EISs) in general (Thompson et al., 1997). This paper describes the results of a further review of 40 EISs produced between 1993 and 1997 and also examines recent changes in the political context for EIA of proposed road developments,including developments in UK transport policy and the UK biodiversity process. The results of the review suggest that the ecological assessment of proposed road developments has improved in some respects, but also highlights the persistence of many shortcomings identified in earlier reviews. The reasons for ongoing failure to address these issues are explored. Key findings include a marked improvement in the extent of reference to consultation with statutory consultees and an increase in the proportion of EISs reporting the results of new ecological surveys. However, while potential ecological impacts were discussed in all the EISs reviewed, many still failed to predict the full range of potential ecological impacts. 相似文献
Managers and regulators have recognized that the fishing public often ignores fish consumption advisories, and the reasons for non-compliance are explored in this paper. Risk assessors acknowledge that there is a social amplification (intensification) of risk where the public perceive a risk as much more severe than do the 'experts' or scientists, and this social amplification is a function of the interaction of hazards with social, psychological and cultural processes. I propose that non-compliance of consumption advisories occurs because of the deamplification of risk in hazards that are familiar and enjoyed, such as fishing and fish consumption. Although the public are generally aware of consumption advisories, they continue to believe the fish are safe to eat, and a high percentage eat the fish they catch. Unlike the amplification of risk, the deamplification of risk from fishing in the face of consumption advisories is partly legitimized by the actions of some governmental agencies, as well as by society at large. It is suggested that a variety of economic benefits and social institutions lead to a discounting of consumption advisories, and the delayed nature of adverse health effects allows for additional disregard. Further, it is suggested that co-management of the risk from contaminated fish would increase public involvement, and therefore compliance. 相似文献
Management of ecosystems has been improved both by our understanding of how ecosystems function, as well as by what people consider to be suitable future land uses. This is particularly true with contaminated lands where decisions must be made about clean-up and future land use. In this paper I synthesize several surveys of public recreational rates and preferences for future land use of the Savannah River Site (SRS), a Department of Energy (DoE) facility located in South Carolina. Four groups of people were interviewed: on-site hunters; sportsmen; local residents attending an event near Aiken, South Carolina; and the general public attending a festival in Columbia, South Carolina. The general public that engaged in recreational activities averaged 20 days/ year or more for hunting and fishing, while sportsmen averaged over 50 days/year. All four groups rated maintaining SRS as a National Environmental Research Park (NERP) and using it for recreation as the highest preferred land uses. The general public rated hiking and camping higher than hunting and fishing, while sportsmen rated hunting higher than hiking and camping. All groups rated using SRS for homes as the lowest, or second lowest, preferred land use. There was disagreement on the ratings for industrial development, with people living closer to the site rating it higher than the general South Carolina population. These data can be used by local planners and managers in decision making regarding clean-up levels and future land use. The relative unanimity of views for cleaning up DoE sites, continued use of the site as a NERP and increased recreational use suggests that different groups of people share similar preferences for future use of SRS, and provides a useful paradigm for considering future land use decisions at other DoE sites nationwide. The relatively low ranking for housing and factories suggests that clean-up levels could be geared to future land use, such as recreation, which are less stringent than residential levels. 相似文献