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641.
Being constantly connected to others via e‐mail and other online messages is increasingly typical for many employees. In this paper, we develop and test a model that specifies how interruptions by online messages relate to negative and positive affect. We hypothesize that perceived interruptions by online messages predict state negative affect via time pressure and that perceived interruptions predict state positive affect via responsiveness to these online messages and perceived task accomplishment. A daily survey study with 174 employees (a total of 811 day‐level observations) provided support for our hypotheses at the between‐person and within‐person level. In addition, perceived interruptions showed a negative direct association with perceived task accomplishment. Our study highlights the importance of being responsive to online messages and shows that addressing only the negative effects of perceived interruptions does not suffice to understand the full impact of interruptions by online messages in modern jobs. 相似文献
642.
Antecedents and consequences of satisfaction with work–family balance: A moderating role of perceived insider status 下载免费PDF全文
This study developed a moderated mediation model to investigate how family‐supportive paid leave and supervision affect employees' satisfaction with work–family balance and in turn their affective organizational commitment and supervisor‐directed organizational citizenship behavior depending on their perceived insider status in the organization. Our analysis of data collected from 118 employee–supervisor dyads in Korean organizations revealed that satisfaction with work–family balance mediated the linkages from family‐supportive supervision to affective organizational commitment and supervisor‐directed organizational citizenship behavior, and the linkage from family‐supportive paid leave to affective organizational commitment. Results further showed that the entire mediational process for family‐supportive supervision was more pronounced for those who perceived themselves to be an insider of their organizations, while the same pattern was not found for the meditational process related to family‐supportive paid leave. Our findings provide theoretical implications for work–family balance research and offer practical suggestions to make employees satisfied with work–family balance. 相似文献
643.
Hurricane Katrina‐linked environmental injustice: race,class, and place differentials in attitudes 下载免费PDF全文
Claims of environmental injustice, human neglect, and racism dominated the popular and academic literature after Hurricane Katrina struck the United States in August 2005. A systematic analysis of environmental injustice from the perspective of the survivors remains scanty or nonexistent. This paper presents, therefore, a systematic empirical analysis of the key determinants of Katrina‐induced environmental injustice attitudes among survivors in severely affected parishes (counties) in Louisiana and Mississippi three years into the recovery process. Statistical models based on a random sample of survivors were estimated, with the results revealing significant predictors such as age, children in household under 18, education, homeownership, and race. The results further indicate that African‐Americans were more likely to perceive environmental injustice following Katrina than their white counterparts. Indeed, the investigation reveals that there are substantial racial gaps in measures of environmental injustice. The theoretical, methodological, and applied policy implications of these findings are discussed. 相似文献
644.
Rural and remote areas of countries such as Australia and the United States are less well‐resourced and often poorer than their city counterparts. When a disaster strikes, therefore, their long‐term recovery can be impeded by being situated ‘over the horizon'. Nonetheless, they are likely to enjoy higher social capital, with ‘locals’ banding together to help restore economic and social life in the wake of a calamitous incident. At the same time, a repeat of extreme events, springing in part from alteration to the landscape through intense human occupation, threatens to derail sustainable recovery processes everywhere, suggesting that renewed emphasis needs to be placed on preparedness. Improved metrics are also required, spanning both pre‐ and post‐disaster phases, to determine effectiveness. Moreover, a focus on the ‘hardening’ of towns offers a better return in limiting damage and potentially hastens the speed of recovery should these places later fall victim to extreme events. 相似文献
645.
Addressing challenges for future strategic‐level emergency management: reframing,networking, and capacity‐building 下载免费PDF全文
The mounting frequency and intensity of natural hazards, alongside growing interdependencies between social‐technical and ecological systems, are placing increased pressure on emergency management. This is particularly true at the strategic level of emergency management, which involves planning for and managing non‐routine, high‐consequence events. Drawing on the literature, a survey, and interviews and workshops with Australia's senior emergency managers, this paper presents an analysis of five core challenges that these pressures are creating for strategic‐level emergency management. It argues that emphasising ‘emergency management’ as a primary adaptation strategy is a retrograde step that ignores the importance of addressing socio‐political drivers of vulnerabilities. Three key suggestions are presented that could assist the country's strategic‐level emergency management in tackling these challenges: (i) reframe emergency management as a component of disaster risk reduction rather than them being one and the same; (ii) adopt a network governance approach; and (iii) further develop the capacities of strategic‐level emergency managers. 相似文献
646.
This paper investigates the effectiveness of protected areas in slowing tropical forest clearing in 64 countries in Asia/Pacific, Africa and Latin America during the period of 2001–2012 by comparing deforestation rates inside and within 10 km outside of the boundaries of protected areas. Annual time series of these deforestation rates were constructed from recently published high‐resolution data on forest clearing from Hansen et al. (2013). For 4,028 parks, panel estimation based on a variety of park characteristics was conducted to test if deforestation was lower in protected areas because of their protected status, or if other factors explained the difference. From a sample of 726 parks established since 2002, a test was also conducted to investigate the effect of park establishment on protection. Findings suggest park size, national park status and management by indigenous people all are significantly associated with effective protection across regions. For the Asia/Pacific region, the test offers compelling evidence that park establishment has a near‐immediate and powerful effect. 相似文献
647.
Evidence of the impacts of the national housing programme on the accessibility of the low‐income population in Rio de Janeiro 下载免费PDF全文
José Renato Barandier Jr. Milena Bodmer Izabella Lentino 《Natural resources forum》2017,41(2):105-118
The Brazilian shift from a primarily rural to a more urban society has created major challenges that public policies must address. One of the most relevant challenges is deep social exclusion in urban areas, especially in terms of adequate housing and access to urban opportunities (e.g., jobs, housing, and services). In this context, land use and transport planning play a critical role in the sustainable development agenda. The work presented here analyses the accessibility of low‐income dwellings licenced under the Brazilian housing programme to the low‐income population. To evaluate the accessibility of the programme's target population, a case study was conducted in the city of Rio de Janeiro, where 58,000 homes licensed under the programme were analysed using GIS tools in terms of the present public transport network and the location of the homes. The amount of time it takes to access public transport on foot and the homes’ locations in relation to major urban opportunities were also analysed. Finally, the same analysis was performed for the future transport network, and the results of the two analyses were compared to identify the scope of the legacy generated by investments in preparation for the 2016 network. 相似文献
648.
R.B. Brennan J.T. Scott A.N. Sharpley H.T. Lally H.P. Jarvie M.J. Bowes B.E. Haggard E. Gbur 《Journal of the American Water Resources Association》2017,53(4):809-821
Phosphorus (P) is a limiting nutrient in freshwater systems and when present in runoff from agricultural lands or urban centers may contribute to excessive periphyton growth. In this study, we examined the link between soil erosion and delivery of eroded soil to streams during flow events, and the impact of that freshly deposited soil on dissolved reactive P (DRP) concentrations and periphyton growth under baseflow conditions when the risk of stream eutrophication is greatest. A microcosm experiment was designed to simulate the release of P from soil which had been amended with different amounts of P fertilizer to overlying water during baseflow conditions. Unglazed tiles, inoculated for five days in a second order stream, were incubated for seven days in microcosms containing soil with eight levels of soil Mehlich‐3 plant available phosphorus (M3P) ranging from 20 to 679 mg/kg M3P. Microcosm DRP was monitored. Following incubation tiles were scraped and the periphyton analyzed for chlorophyll a. Microcosm DRP concentrations increased with increasing soil M3P and equilibrium phosphorus concentration (EPC0). Relationships between M3P, EPC0, and DRP were nonlinear and increases in soil M3P and/or DRP had a greater impact on biomass accumulation when these parameters were above threshold values of 30 mg/kg M3P and 0.125 mg/L DRP. Significantly, this ecological threshold corresponds to the agronomic thresholds above which increased soil M3P does not increase plant response. 相似文献
649.
Water Use for Hydraulic Fracturing of Oil and Gas in the South Platte River Basin,Colorado 下载免费PDF全文
Ella L. Walker Aspen M. Anderson Laura K. Read Terri S. Hogue 《Journal of the American Water Resources Association》2017,53(4):839-853
Water use for oil and gas development (i.e., hydraulic fracturing) is a concern in semiarid basins where water supply is often stressed to meet demands, and oil and gas production can exacerbate the situation. Understanding the impacts of water use for hydraulic fracturing (HF) on water availability in semiarid regions is critical for management and regulatory decisions. In the current work, we quantify water use for HF at several scales — from municipal to state‐wide — using the IHS Enerdeq database for the South Platte Basin. In addition, we estimate produced water (a by‐product of oil and gas production), using data from the Colorado Oil and Gas Conservation Commission to explore reuse scenarios. The South Platte River Basin, located in northeastern Colorado, encompasses the Denver‐Metro area. The basin has one of the most productive oil and gas shale formations in Colorado, with much of the production occurring in Weld County. The basin has experienced higher horizontal drilling rates coupled with an increasing population. Results show water use for horizontal and vertical wells averages 11,000 and 1,000 m3, respectively. Water use for HF in the South Platte Basin totaled 0.63% of the basin's 2014 total water demand. For Weld County, water use for HF was 2.4% of total demand, and for the city of Greeley, water use was 7% of total demand. Produced water totaled 9.4 Mm3 in the basin for 2014, which represents 42% of the total water used for HF. 相似文献
650.
An Open Source GIS‐Based Decision Support System for Watershed Evaluation of Best Management Practices 下载免费PDF全文
Hui Shao Wanhong Yang John Lindsay Yongbo Liu Zhiqiang Yu Anatoliy Oginskyy 《Journal of the American Water Resources Association》2017,53(3):521-531
Economic costs, water quantity/quality benefits, and cost effectiveness of agricultural best management practices (BMPs) at a watershed scale are increasingly examined using integrated economic‐hydrologic models. However, these models are typically complex and not user‐friendly for examining the effects of various BMP scenarios. In this study, an open source geographic information system (GIS)‐based decision support system (DSS), named the watershed evaluation of BMPs (WEBs), was developed for creating BMP scenarios and simulating economic costs and water quantity/quality benefits at farm field, subbasin, and watershed scales. This DSS or WEBs interface integrated a farm economic model, the Soil and Water Assessment Tool (SWAT), and an optimization model within Whitebox Geospatial Analysis Tools (GAT), an open source GIS software. The DSS was applied to the 14.3‐km2 Gully Creek watershed, a coastal watershed in southern Ontario, Canada that drains directly into Lake Huron. BMPs that were evaluated included conservation tillage, nutrient management, cover crop, and water and sediment control basins. In addition to assessing economic costs, water quantity/quality benefits, and cost effectiveness of BMPs, the DSS can be also used to examine prioritized BMP types/locations and corresponding economic and water quantity/quality tradeoffs in the study watershed based on environmental targets or budget constraints. Further developments of the DSS including interface transfer to other watersheds are also discussed. Editor's note : This paper is part of the featured series on SWAT Applications for Emerging Hydrologic and Water Quality Challenges. See the February 2017 issue for the introduction and background to the series. 相似文献