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221.
Walter LS 《Disasters》1990,14(1):20-35
Various kinds of Satellites, including communications, meteorology, remote sensing and geophysics satellites, are, or may become, useful tools in disaster prevention, preparedness and relief. They already provide operational capability for storm warnings and search-and-rescue efforts. Other capabilities, such as improved flood prediction and global mobile communications during relief, are close within reach. Still others, such as earthquake prediction, require considerable research. Close cooperation and communication between space technologists and disaster-management specialists will be needed in guiding research and designing and testing satellite systems. It is hoped that the International Decade for Natural Disaster Reduction can provide a framework for such activities. 相似文献
222.
Walter H. Piper 《Behavioral ecology and sociobiology》2011,65(7):1329-1351
Behavioral ecologists generally agree that animals derive benefits from familiarity with spaces that they inhabit or visit,
yet site familiarity is rudimentary or lacking in most models of habitat selection. In this review, I examine evidence for
the occurrence of site familiarity and its fitness benefits, describe the difficulty of measuring site familiarity, note its
omission from the influential ideal free and ideal despotic models, and use a literature search to test an assumption of the
ideal models that has become widespread in habitat selection theory: that animals behave without regard for site familiarity.
I find little support for such “familiarity blindness” in vertebrates. Next I discuss how the study of public information
has drawn attention away from site familiarity and point out that both kinds of information are likely to be important in
habitat selection. I proceed to examine current models of initial settlement (exploration and settlement of prebreeders on
first territories) and optional resettlement (site fidelity or dispersal by established breeders following a period of prospecting)
and find that the latter include only basic forms of site familiarity. Hence, I develop the concept that an inhabited space
holds a unique “private value” to an animal based on its familiarity with the space and offer a simple model for optional
resettlement based on private value that generates several novel predictions, including site fidelity based on cumulative
breeding site familiarity and high site fidelity among species with complex territories. 相似文献
223.
224.
Walter J. Hamming Robert D. Macphee James R. Taylor 《Journal of the Air & Waste Management Association (1995)》2013,63(1):7-16
Sampling for nitrogen and sulfur dioxides was initiated at several National Air Sampling Network stations in 1959 using a sampler developed for that purpose. In 1961 the Gas Sampling Network was expanded to its maximum of 49 stations. Sampling equipment and collecting solutions are supplied and chemical analyses performed by the network laboratories. Sampling and analysis procedures are described briefly. Average and maximum 24-hour concentrations of nitrogen dioxide and sulfur dioxide observed at 48 stations during 1961-1963 are presented. 相似文献
225.
Anthony J. Yankel Ian H. von Lindern Stephen D. Walter 《Journal of the Air & Waste Management Association (1995)》2013,63(8):763-767
This paper is directed to those persons concerned with the relationship between blood lead levels and environmental exposures to lead. Information presented in this paper represents one of the largest collections of epidemiologica! data relating blood lead levels to environmental exposures. The observed annual average ambient air lead concentration ranged from approximately 0.5 ng Pb/m3 to 23 ng Pb/m3, while lead in soil ranged from 50-24,600 ppm. Blood lead levels of children (ages 1-9 years) are related to a host of environmental variables via regression techniques. Blood lead levels were found to be most influenced by five variables. These variables are: ambient air lead, soil lead, age of the child, dustiness of the home, and occupational status of the parents. It is concluded, based upon the results of this study, that any environmental control strategy should address both the air and the soil. Soil levels in excess of 1000 ppm lead as well as air lead levels greater than 2 jug Pb/m3, 30 day average, were found to be unacceptable. 相似文献
226.
227.
David W. Porter Bruce P. Gibbs Walter F. Jones Peter S. Huyakorn L. Larry Hamm Gregory P. Flach 《Journal of contaminant hydrology》2000,42(2-4)
Engineering projects involving hydrogeology are faced with uncertainties because the earth is heterogeneous, and typical data sets are fragmented and disparate. In theory, predictions provided by computer simulations using calibrated models constrained by geological boundaries provide answers to support management decisions, and geostatistical methods quantify safety margins. In practice, current methods are limited by the data types and models that can be included, computational demands, or simplifying assumptions. Data Fusion Modeling (DFM) removes many of the limitations and is capable of providing data integration and model calibration with quantified uncertainty for a variety of hydrological, geological, and geophysical data types and models. The benefits of DFM for waste management, water supply, and geotechnical applications are savings in time and cost through the ability to produce visual models that fill in missing data and predictive numerical models to aid management optimization. DFM has the ability to update field-scale models in real time using PC or workstation systems and is ideally suited for parallel processing implementation. DFM is a spatial state estimation and system identification methodology that uses three sources of information: measured data, physical laws, and statistical models for uncertainty in spatial heterogeneities. What is new in DFM is the solution of the causality problem in the data assimilation Kalman filter methods to achieve computational practicality. The Kalman filter is generalized by introducing information filter methods due to Bierman coupled with a Markov random field representation for spatial variation. A Bayesian penalty function is implemented with Gauss–Newton methods. This leads to a computational problem similar to numerical simulation of the partial differential equations (PDEs) of groundwater. In fact, extensions of PDE solver ideas to break down computations over space form the computational heart of DFM. State estimates and uncertainties can be computed for heterogeneous hydraulic conductivity fields in multiple geological layers from the usually sparse hydraulic conductivity data and the often more plentiful head data. Further, a system identification theory has been derived based on statistical likelihood principles. A maximum likelihood theory is provided to estimate statistical parameters such as Markov model parameters that determine the geostatistical variogram. Field-scale application of DFM at the DOE Savannah River Site is presented and compared with manual calibration. DFM calibration runs converge in less than 1 h on a Pentium Pro PC for a 3D model with more than 15,000 nodes. Run time is approximately linear with the number of nodes. Furthermore, conditional simulation is used to quantify the statistical variability in model predictions such as contaminant breakthrough curves. 相似文献
228.
Bimal Raj Regmi Cassandra Star Walter Leal Filho 《Mitigation and Adaptation Strategies for Global Change》2016,21(3):461-478
A key challenge in climate change adaptation in developing countries as a whole, and to handling global change in particular, is to link local adaptation needs on the one hand, with national adaptation initiatives on the other, so that vulnerable households and communities can directly benefit. This study assesses the impact of the Nepal government’s efforts to promote its Local Adaptation Plan of Action (LAPA) and its applicability to other least developed countries (LDCs). Based on data gathered from two field studies in Nepal, the research shows that the Nepal’s LAPA has succeeded in mobilizing local institutions and community groups in adaptation planning and recognizing their role in adaptation. However, the LAPA approach and implementation have been constrained by sociostructural and governance barriers that have failed to successfully integrate local adaptation needs in local planning and increase the adaptive capacity of vulnerable households. This paper describes the mechanisms of suitable governance strategies for climate change adaptation specific to Nepal and other LDCs. It also argues the need to adopt an adaptive comanagement approach, where the government and all stakeholders identify common local- and national-level mainstreaming strategy for knowledge management, resource mobilization, and institutional development, ultimately using adaptation as a tool to handle global change. 相似文献
229.
Stuczynski T Siebielec G Daniels WL Daniels WL McCarty G Chaney RL 《Journal of environmental quality》2007,36(4):1154-1162
Smelter waste deposits pose an environmental threat worldwide. Biosolids are potentialy useful in reclamation of such sites. Biological aspects of revegetation of Zn and Pb smelter wastelands using biosolids are discussed in this report. The goal of the studies was to assess to what extent biosolid treatment would support ecosystem functioning as measured by biological indicators such as enzyme activities of revegetated metal waste or plant growth. Another crucial aspect was related to the assessment of metal transfer to the ecosystem which could affect the health of local fauna and also create a food chain risk. A field experiment was conducted on a smelter waste deposit in Piekary Slaskie, Silesia, Poland, with two separate fields - established on wastes from the Welz and Doerschel smelting processes. The tested methods allowed revegetation of the fields - application of municipal biosolid at the rate 300 dry t ha(-1) combined with the incorporation of commercial lime in a mixed oxide and carbonate form at the rate of 1.5 and 30 t for Welz waste or use of a 30 cm by-product lime cap followed by incorporation of biosolid at a rate of 300 t ha(-1) for the more acidic Doerschel waste. Studies on biological activities demonstrated that the reclamation methods used are an effective way to establish new, fully-functioning ecosystems that support plant growth. They also provided strong evidence that forage crops grown on Zn, Cd and Pb contaminated sites reclaimed using lime and biosolids do not pose identified risk for wildlife and food safety. 相似文献
230.
Escalada JP Pajares A Gianotti J Massad WA Bertolotti S Amat-Guerri F García NA 《Chemosphere》2006,65(2):237-244
The present work studies the visible-light-promoted photodegradation of the colorless fungicide carbendazim (methyl 2-benzimidazolecarbamate) and several 2-substituted benzimidazoles (SBZ's), in water or water-methanol solution, in the presence of air and, as a photosensitizer, the synthetic xanthene dye Rose Bengal (RB) or the natural pigment riboflavin (Rf). The results indicate that the degradation of each particular SBZ depends on its chemical structure and on the sensitizer employed. In the presence of RB, the degradation always operates via a singlet molecular oxygen (O(2)((1)Delta(g)))-mediated mechanism, through a highly efficient process, as deduced from the comparison of the rate constants for physical and chemical quenching of O(2)((1)Delta(g)). In the presence of Rf, the visible-light irradiation of any of the studied SBZ's produces a series of competitive processes that depend on the relative concentrations of Rf and SBZ. These processes include the quenching of excited singlet and triplet Rf states by the SBZ and the generation of both O(2)((1)Delta(g)) and superoxide radical anion (O(2)(-)), the latter generated by electron transfer from excited Rf species to the dissolved oxygen. The overall result is the photodegradation of the SBZ and the photoprotection of the sensitizer. 相似文献