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71.
This study quantitatively explores whether land cover changes have a substantive impact on simulated streamflow within the tropical island setting of Puerto Rico. The Precipitation Runoff Modeling System (PRMS) was used to compare streamflow simulations based on five static parameterizations of land cover with those based on dynamically varying parameters derived from four land cover scenes for the period 1953‐2012. The PRMS simulations based on static land cover illustrated consistent differences in simulated streamflow across the island. It was determined that the scale of the analysis makes a difference: large regions with localized areas that have undergone dramatic land cover change may show negligible difference in total streamflow, but streamflow simulations using dynamic land cover parameters for a highly altered subwatershed clearly demonstrate the effects of changing land cover on simulated streamflow. Incorporating dynamic parameterization in these highly altered watersheds can reduce the predictive uncertainty in simulations of streamflow using PRMS. Hydrologic models that do not consider the projected changes in land cover may be inadequate for water resource management planning for future conditions.  相似文献   
72.
Shorebird researchers and land managers recognize human disturbance as a serious threat facing shorebirds. Yet, a common understanding of what defines human disturbance is lacking. To address this issue, we employed the Delphi technique, an iterative consensus-building social science method, to bring scientists and managers together to develop a shared definition of human disturbance and a list of priority human activities that could affect migratory shorebirds. During four iterative rounds, participants with extensive knowledge on human disturbance to shorebirds from varying geographic locations within the Northeastern U.S. worked together to produce a shared understanding. Through analyzing participants’ open-ended responses, we identified important themes for the definition. The participants then refined and ranked these themes through surveys, and the top-ranked themes were used to draft a final definition also reviewed by the participants. Participants provided 94 human activities in response to our request to list and describe all potential human disturbances that affect shorebirds during fall migration. From there, we grouped the activities into 23 categories. Through rating and ranking tasks, participants reduced this list to 12 priority disturbance categories that represent the perceived most significant human disturbances in the Northeastern United States. We also compared responses among the different participant groups (i.e., managers, scientists, and manager/scientists), finding that groups’ responses generally did not significantly differ. While nearly all participants were satisfied with the process, we provide some suggestions to improve it. The outputs of the Delphi technique have informed a best practices guidance document for shorebird management.  相似文献   
73.
An on-site visitor survey instrument was developed to examine visitor perceptions of resource impacts resulting from backcountry hiking activities. The survey was conducted in the Bear Lake Corridor of Rocky Mountain National Park, CO and examined visitor characteristics that may influence visitor perceptions of specific resource conditions. Findings indicate that visitors are more perceptive of recreation-related resource impacts that are the result of undesirable behavior and, while visitors do perceive resource impacts, visitors tend to be more affected by crowding. Factors such as local ecological knowledge and knowledge of minimal-impact practices positively influence visitor perceptions of resource impacts. These findings support the use of visitor education on ecological knowledge and minimum-impact as a means of increasing visitor awareness of recreation impact issues.  相似文献   
74.
Designing agroecosystems that are compatible with the conservation of biodiversity is a top conservation priority. However, the social variables that drive native biodiversity conservation in these systems are poorly understood. We devised a new approach to identify social–ecological linkages that affect conservation outcomes in agroecosystems and in social‐ecological systems more broadly. We focused on coastal agroforests in Fiji, which, like agroforests across other small Pacific Islands, are critical to food security, contain much of the country's remaining lowland forests, and have rapidly declining levels of native biodiversity. We tested the relationships among social variables and native tree species richness in agroforests with structural equation models. The models were built with data from ecological and social surveys in 100 agroforests and associated households. The agroforests hosted 95 native tree species of which almost one‐third were endemic. Fifty‐eight percent of farms had at least one species considered threatened at the national or international level. The best‐fit structural equation model (R2 = 47.8%) showed that social variables important for community resilience—local ecological knowledge, social network connectivity, and livelihood diversity—had direct and indirect positive effects on native tree species richness. Cash‐crop intensification, a driver of biodiversity loss elsewhere, did not negatively affect native tree richness within parcels. Joining efforts to build community resilience, specifically by increasing livelihood diversity, local ecological knowledge, and social network connectivity, may help conservation agencies conserve the rapidly declining biodiversity in the region.  相似文献   
75.

Aims

A sociological and anthropological view of culture was used to investigate how work culture, independent of “safety culture”, may affect safety in the workplace. We explored how work cultures of nurses and physical/occupational therapists (PT/OTs) in two acute care hospitals are related to the adoption of patient lifting devices.

Methods

Focus groups were conducted between 2006 and 2009, seven with nurse staff (n = 39) and two with PT/OT staff (n = 17), to explore issues concerning a Minimal Manual Lift Environment policy, initiated in 2004, and subsequent use of patient lift equipment. Audio recordings of the sessions were transcribed; text data were analyzed using N6-QSR. Cultural facilitators and barriers to the adoption of patient lift equipment were examined.

Results

Data revealed cultural similarities and differences between these healthcare professions. Both displayed a “patient first” approach to care-giving which may promote lift device use for patients’ benefits, not necessarily for staff safety. Also, the implied purpose of patient lifting devices clashes with the nurses’ cultural emphasis on compassion, and with PT/OTs’ cultural emphasis on independence except when use increases patients’ independence.

Conclusions

Cultural expressions regarding the nature of care-giving among healthcare professionals may affect the propensity to adopt safety measures in complex ways. The workers’ understanding of the purpose of their work, and acceptable means of conducting it, should be understood before implementing safety interventions. The utilization of lift assist teams, who are not socialized into the cultures of nursing or PT/OT, may be one means of circumventing cultural barriers to lift equipment use.  相似文献   
76.
The clearance of indigenous riparian vegetation and removal of large woody debris (LWD) from streams combined with the planting of exotic plant species has resulted in widespread detrimental impacts on the fluvial geomorphology and aquatic ecology of Australian rivers. Vegetation exerts a significant influence on fluvial geomorphology by affecting resistance to flow, bank strength, sediment storage, bed stability and stream morphology and is important for aquatic ecosystem function. As the values of indigenous riparian vegetation are becoming better recognised by Australian river managers, large amounts of money and resources are being invested in the planting of indigenous riparian vegetation as part of river rehabilitation programs. This paper summarises the results of an investigation into the survival, growth and regeneration rates of a series of trial native riparian vegetation plantings on in-channel benches in the Hunter Valley of southeastern Australia. The trials were poorly designed for statistical analysis and the paper highlights a number of shortcomings in the methods used. As a result, a new approach to riparian vegetation rehabilitation is outlined that promotes the use of scientific principles and understanding. Appropriate species should be selected using a combination of remnant vegetation surveys, historical records, palynology and field trials. A number of important factors should be considered in the rehabilitation of riparian vegetation to achieve worthwhile results. These include flood disturbance, vegetation zonation, vegetation succession, substrate composition, corridor planting width, planting techniques, native plant regeneration, LWD recruitment and adaptive ecosystem management. This approach, if adopted, revised and improved by river managers, should result in greater success than has been achieved by previous riparian vegetation rehabilitation efforts in Australia.  相似文献   
77.
There is a general assumption, based on macroeconomic studies, that remittances will rise following major sudden‐onset natural disasters. This is confirmed by a few assessments involving country‐specific research, and usually short‐term data. This study, questioning conventional wisdom, reviewed and graphed annual and quarterly remittance flows using International Monetary Fund and World Bank data from 2000–14 for 12 countries that confronted 18 major natural disasters. It found that, regardless of event type, annual remittances rose steadily from 2000–14 except for after the 2008–09 financial crisis. Post disaster, there was a quarterly increase in the majority of cases (confirming previous research) but there was seldom an annual increase in the year of the disaster greater than the average annual increase in 2000–14. It appears that remittance senders rush to provide assistance after a natural disaster, but since their own financial situation has not changed, the immediate increase is compensated by a later decrease.  相似文献   
78.
79.
Development of an algorithm for an EEG-based driver fatigue countermeasure   总被引:6,自引:0,他引:6  
PROBLEM: Fatigue affects a driver's ability to proceed safely. Driver-related fatigue and/or sleepiness are a significant cause of traffic accidents, which makes this an area of great socioeconomic concern. Monitoring physiological signals while driving provides the possibility of detecting and warning of fatigue. The aim of this paper is to describe an EEG-based fatigue countermeasure algorithm and to report its reliability. METHOD: Changes in all major EEG bands during fatigue were used to develop the algorithm for detecting different levels of fatigue. RESULTS: The software was shown to be capable of detecting fatigue accurately in 10 subjects tested. The percentage of time the subjects were detected to be in a fatigue state was significantly different than the alert phase (P<.01). DISCUSSION: This is the first countermeasure software described that has shown to detect fatigue based on EEG changes in all frequency bands. Field research is required to evaluate the fatigue software in order to produce a robust and reliable fatigue countermeasure system. IMPACT ON INDUSTRY: The development of the fatigue countermeasure algorithm forms the basis of a future fatigue countermeasure device. Implementation of electronic devices for fatigue detection is crucial for reducing fatigue-related road accidents and their associated costs.  相似文献   
80.
Lake Superior receives inputs from approximately 2,800 tributaries that provide nutrients and dissolved organic matter (DOM) to the nearshore zone of this oligotrophic lake. Here, we review the magnitude and timing of tributary export and plume formation in Lake Superior, how these patterns and interactions may shift with global change, and how emerging technologies can be used to better characterize tributary–lake linkages. Peak tributary export occurs during snowmelt‐driven spring freshets, with additional pulses during rain‐driven storms. Instream processing and transformation of nitrogen, phosphorus, and dissolved organic carbon (DOC) can be rapid but varies seasonally in magnitude. Tributary plumes with elevated DOC concentration, higher turbidity, and distinct DOM character can be detected in the nearshore during times of high runoff, but plumes can be quickly transported and diluted by in‐lake currents and mixing. Understanding the variability in size and load of these tributary plumes, how they are transported within the lake, and how long they persist may be best addressed with environmental sensors and remote sensing using autonomous and unmanned vehicles. The connections between Lake Superior and its tributaries are vulnerable to climate change, and understanding and predicting future changes to these valuable freshwater resources will require a nuanced and detailed consideration of tributary inputs and interactions in time and space.  相似文献   
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