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121.
This article is excerpted from Chapter 1 of Environmental Management Information Systems, which will be published by McGraw-Hill in 1994. A central theme of the book is that all successful implementations of environmental management information systems (EMIS) are based on the appropriate alignment of goals and procedures from three enterprise domains: business processes, environmental management, and information systems. Environmental managers (EM) and information systems (IS) professionals have each been guilty of seeing their functions as primary, domains of specialized scientific expertise inaccessible to outsiders. In fact, however, the enterprise is the customer for both domains; without successful business strategies and systems the enterprise does not require either EM or IS wizards. This article shows why and how essential it is that each of the three domains understands enough of the other two domains to structure good decisions.  相似文献   
122.
Removal of selenate from water by zerovalent iron   总被引:1,自引:0,他引:1  
Zerovalent iron (ZVI) has been widely used in the removal of environmental contaminants from water. In this study, ZVI was used to remove selenate [Se(VI)] at a level of 1000 microg L(-1) in the presence of varying concentrations of Cl-, SO(2-)4, NO(-)3, HCO(-)3, and PO(3-)4. Results showed that Se(VI) was rapidly removed during the corrosion of ZVI to iron oxyhydroxides (Fe(OH)). During the 16 h of the experiments, 100 and 56% of the added Se(VI) was removed in 10 mM Cl- and SO(2-)4 solutions under a closed contained system, respectively. Under an open condition, 100 and 93% of the added Se(VI) were removed in the Cl- and SO(2-)4 solutions, respectively. Analysis of Se species in ZVI-Fe(OH) revealed that selenite [Se(IV)] and nonextractable Se increased during the first 2 to 4 h of reaction, with a decrease of Se(VI) in the Cl- experiment and no detection of Se(VI) in the SO(2-)4 experiment. Two mechanisms can be attributed to the rapid removal of Se(VI) from the solutions. One is the reduction of Se(VI) to Se(IV), followed by rapid adsorption of Se(IV) to Fe(OH). The other is the adsorption of Se(VI) directly to Fe(OH), followed by its reduction to Se(IV). The results also show that there was little effect on Se(VI) removal in the presence of Cl- (5, 50, and 100 mM), NO(-)3 (1, 5, and 10 mM), SO(2-)4 (5 mM), HCO(-)3 (1 and 5 mM), or PO(3-)4 (1 mM) and only a slight effect in the presence of SO(2-)4 (50 and 100 mM), HCO(-)3 (10 mM), and PO(3-)4 (5 mM) during a 2-d experiment, whereas 10 mM PO(3-)4 significantly inhibited Se(VI) removal. This work suggests that ZVI may be an effective agent to remove Se from Se-contaminated agricultural drainage water.  相似文献   
123.
Does religion affect legislators’ behavior on environmental policy in the US? Studies of environmental policy making have not examined this question, although the literature suggests that religion might affect legislative behavior on environmental policy. This study examines the relationship between US House members’ religion and roll-call voting on environmental legislation from 1973 to 2009. It finds significant differences across religious traditions. Legislators’ party and characteristics of constituencies relevant to environmental politics increasingly, but not entirely, mediate these differences.  相似文献   
124.
Multiple paternity was recently observed in a population of the brown smoothhound shark, Mustelus henlei, from Las Barrancas, Baja California Sur, Mexico, with litters demonstrating the greatest percentage of multiple paternity for any shark species (93 % of litters and an average number of sires = 2.3). To determine whether this frequency is consistent elsewhere in the species’ range, 4 polymorphic microsatellite loci were used to determine the frequency of multiple paternity in 18 litters of M. henlei from Santa Catalina Island, CA, sampled in 2004, 2008, and 2012. Multiple paternity varied among sampling years with 2004 demonstrating multiple sires for 40 % of sampled litters (n = 10) with an average of 1.4 sires per litter and 2008/2012 demonstrating a total lack of multiply sired litters (n = 8). Although multiple paternity was detected in this study, the range of frequencies observed is lower than that observed in the Mexican population. Based on these findings, investigators should take location into consideration when assessing the existence of multiple paternity in future studies of elasmobranch species.  相似文献   
125.
Organic aerosol is the least understood component of ambient fine particulate matter (PM2.5). In this study, organic and elemental carbon (OC and EC) within ambient PM2.5 over a three-year period at a forested site in the North Carolina Piedmont are presented. EC exhibited significant weekday/weekend effects and less significant seasonal effects, in contrast to OC, which showed strong seasonal differences and smaller weekend/weekday effects. Summer OC concentrations are about twice as high as winter concentrations, while EC was somewhat higher in the winter. OC was highly correlated with EC during cool periods when both were controlled by primary combustion sources. This correlation decreased with increasing temperature, reflecting higher contributions from secondary organic aerosol, likely of biogenic origin. PM2.5 radiocarbon data from the site confirms that a large fraction of the carbon in PM2.5 is indeed of biogenic origin, since modern (non-fossil fuel derived) carbon accounted for 80% of the PM2.5 carbon over the course of a year. OC and EC exhibited distinct diurnal profiles, with summertime OC peaking in late evening and declining until midday. During winter, OC peaked during the early morning hours and again declined until midday. Summertime EC peaked during late morning hours except on weekends. Wintertime EC often peaked in late PM or early AM hours due to local residential wood combustion emissions. The highest short term peaks in OC and EC were associated with wildfire events. These data corroborate recent source apportionment studies conducted within 20 km of our site, where oxidation products of isoprene, α-pinene, and β-caryophyllene were identified as important precursors to organic aerosols. A large fraction of the carbon in rural southeastern ambient PM2.5 appears to be of biogenic origin, which is probably difficult to reduce by anthropogenic controls.  相似文献   
126.
127.
A measure of soil P status in agricultural soils is generally required for assisting with prediction of potential P loss from agricultural catchments and assessing risk for water quality. The objectives of this paper are twofold: (i) investigating the soil P status, distribution, and variability, both spatially and with soil depth, of two different first-order catchments; and (ii) determining variation in soil P concentration in relation to catchment topography (quantified as the "topographic index") and critical source areas (CSAs). The soil P measurements showed large spatial variability, not only between fields and land uses, but also within individual fields and in part was thought to be strongly influenced by areas where cattle tended to congregate and areas where manure was most commonly spread. Topographic index alone was not related to the distribution of soil P, and does not seem to provide an adequate indicator for CSAs in the study catchments. However, CSAs may be used in conjunction with soil P data for help in determining a more "effective" catchment soil P status. The difficulties in defining CSAs a priori, particularly for modeling and prediction purposes, however, suggest that other more "integrated" measures of catchment soil P status, such as baseflow P concentrations or streambed sediment P concentrations, might be more useful. Since observed soil P distribution is variable and is also difficult to relate to nationally available soil P data, any assessment of soil P status for determining risk of P loss is uncertain and problematic, given other catchment physicochemical characteristics and the sampling strategy employed.  相似文献   
128.
Analysis of satellite-telemetry data mostly occurs long after it has been collected, due to the time and effort needed to collate and interpret such material. Delayed reporting reduces the usefulness of such data for nature conservation where timely information about animal movements is required. To counter this problem, we present a novel approach which combines automated analysis of satellite-telemetry data with rapid communication of insights derived from such data. A relatively simple algorithm (based on radial and angular velocity calculated from fixes) allowed instantaneous detection of excursions away from settlement areas and automated calculation of home ranges on the remaining data. Automating the detection of both excursions and home-range calculations enabled us to disseminate ecological insights from satellite-tag data instantaneously through a dedicated web portal. The automated analysis, interpretation, and communication of satellite-tag and other ecological data offer clear benefits to nature conservation research and practice.  相似文献   
129.
正The Journal of Environmental Sciences(JES)is honored to welcome Professors/Drs William A.Mitch,Jiuhui Qu,Susan D.Richardson,Jerald L.Schnoor,Hongxiao Tang,Shu Tao,and Hugh A.Tilson to serve on the Editorial Advisory Board(EAB).Their tremendous experience in scientific publications,leading expertise in topic areas pertinent to JES,diverse international networks/perspectives,and exemplary dedication to scientific excellence will guide and help the continuing healthy growth of JES.  相似文献   
130.
Over the last decade, New Zealand has implemented innovative reforms in respect of natural resource and environmental management. These include the Resource ManagementAct 1991 (RMA), a notable feature of which is the adoption of 'sustainable management' as the key principle guiding resource allocation and use. This and other features of the new administrative context for resource management strongly suggest a prominent role for geographicinformation systems (GIS) and related spatial information technology. In this paper we present an outline of the Regional Resource Evaluation Project (RREP), a project that has been established to explore and demonstrate the capabilities of GIS and related spatial information technology in the context of resource analysis and decision making. To date, the RREP has achieved important outcomes in terms of database design and development. An extensive information base which incorporates data on the physical and natural environment, patterns of human activity, and on social and demographic characteristics has been assembled. We describe the information systems, as well as some of the technical issues that attend to database design and development.We also provide brief reviews of two applications of the GIS to resource evaluation. One relates to the evaluation of changes in regional land use, with a focus on natural habitats. The other is concerned with land suitability assessment for plantation forestry.  相似文献   
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