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751.
J. G. Arnold R. Srinivasan R. S. Muttiah P. M. Allen 《Journal of the American Water Resources Association》1999,35(5):1037-1051
This paper describes the application of a continuous daily water balance model called SWAT (Soil and Water Assessment Tool) for the conterminous U.S. The local water balance is represented by four control volumes; (1) snow, (2) soil profile, (3) shallow aquifer, and (4) deep aquifer. The components of the water balance are simulated using “storage” models and readily available input parameters. All the required databases (soils, landuse, and topography) were assembled for the conterminous U.S. at 1:250,000 scale. A GIS interface was utilized to automate the assembly of the model input files from map layers and relational databases. The hydrologic balance for each soil association polygon (78,863 nationwide) was simulated without calibration for 20 years using dominant soil and land use properties. The model was validated by comparing simulated average annual runoff with long term average annual runoff from USGS stream gage records. Results indicate over 45 percent of the modeled U.S. are within 50 mm of measured, and 18 percent are within 10 mm without calibration. The model tended to under predict runoff in mountain areas due to lack of climate stations at high elevations. Given the limitations of the study, (i.e., spatial resolution of the data bases and model simplicity), the results show that the large scale hydrologic balance can be realistically simulated using a continuous water balance model. 相似文献
752.
The oil and gas industry in Norway has taken into use and is developing ICT-based work processes to improve efficiency and safety. Protection of information resources and technology; ensuring safe and secure processing of information; and ensuring reliable and safe flow of information is essential for both production and protection in such ICT-intensive organizations. Information systems security (IS) thus matters for major accident prevention. In the ICT-based work processes in the oil and gas industry new challenges for IS security occur related to: increased need for availability and integrity of information; merge of process safety systems and ICT-systems; manual use of information resources; and flow of information between distributed actors. These challenges imply new requirements for IS management: More focus on availability and integrity as protection principles; resilience-based approaches as a supplement to formal management approaches; validation of information flows; and integration of loss prevention approaches. 相似文献
753.
Sebastián Villasante David Rodríguez-González Manel Antelo Susana Rivero-Rodríguez José A. de Santiago Gonzalo Macho 《Ambio》2013,42(8):923-936
In this paper we examine the effect of Gross Domestic Product (GDP) on the level of fish intake in China in comparison with the rest of the world. We also analyse the origin and destination of China’s seafood products in order to understand the main patterns during the last decades. The results show that in the 1961–2011 period the rate of growth of the GDP in China doubled that of other developing regions, while the daily fish intake of China increased fourfold, making China the largest fish consumer in the world. Given the size and scale of China’s role in production, consumption, and global transformation of seafood markets, China is shaping a new era of industrialization in the history of the fishing industry. 相似文献
754.
This paper examines some of the social processes associated with disaster conditions. Utilising an asset‐based perspective of community capacity, it focuses on four types of normative systems to interpret the ability of communities to manage disasters through market‐, bureaucratic‐, associative‐, and communal‐based norms. Drawing on experience of a wildfire in the Crowsnest Pass region of southwest Alberta, Canada, in 2003, the tensions and compatibilities among these normative systems are evaluated through interviews with 30 community leaders. The results confirm the contributions of all types of social capital to resiliency, the necessity for rapid use of place‐based knowledge, and the importance of communication among all types and levels of agents. In addition, they point to the value of identifying and managing potential conflicts among the normative systems as a means to maximising their contributions. The integration of local networks and groups into the more general disaster response minimised the impacts on health and property. 相似文献
755.
Abstract: We used socioeconomic models that included economic inequality to predict biodiversity loss, measured as the proportion of threatened plant and vertebrate species, across 50 countries. Our main goal was to evaluate whether economic inequality, measured as the Gini index of income distribution, improved the explanatory power of our statistical models. We compared four models that included the following: only population density, economic footprint (i.e., the size of the economy relative to the country area), economic footprint and income inequality (Gini index), and an index of environmental governance. We also tested the environmental Kuznets curve hypothesis, but it was not supported by the data. Statistical comparisons of the models revealed that the model including both economic footprint and inequality was the best predictor of threatened species. It significantly outperformed population density alone and the environmental governance model according to the Akaike information criterion. Inequality was a significant predictor of biodiversity loss and significantly improved the fit of our models. These results confirm that socioeconomic inequality is an important factor to consider when predicting rates of anthropogenic biodiversity loss. 相似文献
756.
Operational sex ratio versus gender density as determinants of copulation duration in the walnut fly,Rhagoletis juglandis (Diptera: Tephritidae) 总被引:5,自引:0,他引:5
In laboratory and field studies of the walnut fly, Rhagoletis juglandis Cresson (Diptera: Tephritidae), we assessed the effect of operational sex ratio on copulation duration and partitioned the
sex ratio effect into component effects due to male density and female density. In our first laboratory experiment, results
were clearly consistent with theoretical expectation: increases in male density were associated with significant increases
in copulation duration while increases in female density were associated with significant decreases in copulation duration.
These component effects yielded a striking composite effect of operational sex ratio (OSR) on copulation duration in which
male-biased ratios were associated with low frequencies of short copulations and female-biased ratios were associated with
high frequencies of short copulations. Consistent with a priori expectations concerning costs of territorial behavior, the
effect of male density on copulation duration was stronger than that of female density. There was no significant interaction
between the effects of gender density on copulation duration: each gender density contributed additively to the composite
OSR effect on copulation duration. In contrast to the effect of OSR, overall density had little effect. Field data corroborated
these findings fully and showed additionally that OSR in the vicinity of fruit tended in nature to be male-biased. In a second
laboratory experiment, we measured copulation duration for individuals exposed alternately to male-biased and female-biased
ratios. Individual flies consistently copulated for longer in male-biased environments than in female-biased ones. We propose
that this plasticity permits individuals to track changes in local sex ratio over space and time and respond appropriately.
Received: 15 November 1995/Accepted after revision: 27 April 1996 相似文献
757.
Managing climate change risks in New York City’s water system: assessment and adaptation planning 总被引:4,自引:0,他引:4
Cynthia Rosenzweig David C. Major Kate Demong Christina Stanton Radley Horton Melissa Stults 《Mitigation and Adaptation Strategies for Global Change》2007,12(8):1391-1409
Managing risk by adapting long-lived infrastructure to the effects of climate change must become a regular part of planning
for water supply, sewer, wastewater treatment, and other urban infrastructure during this century. The New York City Department
of Environmental Protection (NYCDEP), the agency responsible for managing New York City’s (NYC) water supply, sewer, and wastewater
treatment systems, has developed a climate risk management framework through its Climate Change Task Force, a government-university
collaborative effort. Its purpose is to ensure that NYCDEP’s strategic and capital planning take into account the potential
risks of climate change—sea-level rise, higher temperature, increases in extreme events, changes in drought and flood frequency
and intensity, and changing precipitation patterns—on NYC’s water systems. This approach will enable NYCDEP and other agencies
to incorporate adaptations to the risks of climate change into their management, investment, and policy decisions over the
long term as a regular part of their planning activities. The framework includes a 9-step Adaptation Assessment procedure.
Potential climate change adaptations are divided into management, infrastructure, and policy categories, and are assessed
by their relevance in terms of climate change time-frame (immediate, medium, and long term), the capital cycle, costs, and
other risks. The approach focuses on the water supply, sewer, and wastewater treatment systems of NYC, but has wide application
for other urban areas, especially those in coastal locations. 相似文献
758.
HENRY LEE II DEBORAH A. REUSSER† JULIAN D. OLDEN‡ SCOTT S. SMITH† JIM GRAHAM§ VIRGINIA BURKETT JEFFREY S. DUKES†† ROBERT J. PIORKOWSKI‡‡ JOHN MCPHEDRAN§§ 《Conservation biology》2008,22(3):575-584
Abstract: Changes in temperature, precipitation, and other climatic drivers and sea-level rise will affect populations of existing native and non-native aquatic species and the vulnerability of aquatic environments to new invasions. Monitoring surveys provide the foundation for assessing the combined effects of climate change and invasions by providing baseline biotic and environmental conditions, although the utility of a survey depends on whether the results are quantitative or qualitative, and other design considerations. The results from a variety of monitoring programs in the United States are available in integrated biological information systems, although many include only non-native species, not native species. Besides including natives, we suggest these systems could be improved through the development of standardized methods that capture habitat and physiological requirements and link regional and national biological databases into distributed Web portals that allow drawing information from multiple sources. Combining the outputs from these biological information systems with environmental data would allow the development of ecological-niche models that predict the potential distribution or abundance of native and non-native species on the basis of current environmental conditions. Environmental projections from climate models can be used in these niche models to project changes in species distributions or abundances under altered climatic conditions and to identify potential high-risk invaders. There are, however, a number of challenges, such as uncertainties associated with projections from climate and niche models and difficulty in integrating data with different temporal and spatial granularity. Even with these uncertainties, integration of biological and environmental information systems, niche models, and climate projections would improve management of aquatic ecosystems under the dual threats of biotic invasions and climate change. 相似文献
759.
Sociological critiques of scientific research processes and their application have developed nuanced understandings of the social, cultural and political forces shaping relationships between science and decision-making. Simultaneously, environmental researchers have sought to construct more engaged, dynamic modes of conducting research to facilitate the application of science in decision-making and action. To date, however, there are relatively few theoretically-oriented approaches that have been able to draw productive connections between the sociological critique and the practical applications that can aid in navigating this complex and diverse milieu. In this article, we propose that the concept of “knowledge governance” can bring together targeted inquiry into the socio-political context in which environmental science is situated, alongside analysis of specific interventions that change knowledge-to-action relationships. Drawing together Jasanoff’s (2005) concept of civic epistemology with Cash et al.’s (2003) knowledge systems for sustainability approach, this knowledge governance inquiry framework offers an integrative lens through which to critically reflect on knowledge-based processes, and incorporate that deeper understanding into intervention efforts. We briefly illustrate its application with reference to a pilot project examining conservation decision-making in the Western Pacific island nation of Palau. 相似文献
760.
Integrated resource management systems: Coupling expert systems with data-base management and geographic information systems 总被引:4,自引:0,他引:4
Decision making in natural resource management is becoming increasingly information-intensive because of the rising public
concerns about resource conservation and environmental quality. The volume of information that must be analyzed and the complexity
of the decision-making process demands that computerized systems be developed to provide decision support services. An integrated
systems approach that couples data-base management, geographic information systems, and expert systems is needed. We refer
to such an approach as integrated resource management automation (IRMA) and describe a prototype system that is currently
being tested in the Nicolet National Forest. This type of information system is likely to play an increasingly important role
in the management of natural resources in the future. 相似文献