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431.
Hospital wastes are infectious wastes generated in hospitals and need to be disposed in such a way that they do not spread
disease. In this experiment, 5, 10, 15 and 20% cow manure (CM) were mixed with hospital wastes (HW), and mixed wastes were
subjected to vermicomposting. In control treatment, only HW was used for vermicomposting. Results suggested that significantly
(P ≤ 0.05) higher total nitrogen content was recorded in vermicomposts when 10% or more CM was added to HW. Higher mineralization
rate (decrease in C/N ratio) and cellulase activity is probably responsible for rapid organic matter decomposition (loss of
total organic carbon). Ergosterol content i.e., total fungal biomass and cellulolytic fungal population were almost constant
initially, but increased in the latter stage of vermicomposting. All the vermicompost samples, prepared in this experiment,
showed the absence of coliform bacteria. Therefore, it could be concluded that 10% CM addition with HW was the most economical
to obtain best quality vermicompost in terms of nutrient content and microbial status. 相似文献
432.
Stamatis Zogaris Alcibiades N. Economou Panayotis Dimopoulos 《Environmental management》2009,43(4):682-697
Ecoregion delineations have gained increased attention in Europe, especially following the Water Framework Directive 2000/60/EC
(WFD), which provides the European Union’s first policy-relevant ecoregion map. However, the WFD’s ecoregions were created
through a minor adaptation of Illies’ (Limnofauna Europaea. Gustav Fisher Verlag, Stuttgart, 1967/1978) freshwater zoogeographic
regions, and the map’s specific boundaries have not been widely evaluated with respect to the WFD’s uses or their biogeographic
accuracy. We examined the WFD ecoregion boundaries in Greece and its neighboring Balkan states by comparing them with the
most prominent freshwater biogeographic boundaries as shown by riverine freshwater fish assemblages. Classification and ordination
analyses of 23 river basin fish assemblages helped delineate natural faunal break boundaries in freshwater species assemblage
distributions depicting major biogeographic barriers to aquatic biota dispersal. However, these biogeographic boundaries differ
from those delineated in the WFD map, suggesting boundary errors and inconsistencies in the delineation method of the WFD
ecoregions. We reviewed specific boundary disagreements and produced a map showing the region’s most prominent freshwater
biogeographic boundaries by charting them on watershed borders among the four biotically dissimilar river basin groups in
the southern Balkans. This regional evaluation reveals both a need to reconcile disparate approaches to ecoregion mapping
and to promote the development of a new policy-relevant inland waters ecoregion framework that would support broad-scale water
management and aquatic conservation. 相似文献
433.
Measuring agricultural sustainability in terms of efficiency: the case of Dutch sugar beet growers 总被引:3,自引:0,他引:3
Sustainability embraces socio-economic and bio-ecological dimensions or attributes. This paper presents a conceptual framework for quantifying sustainability on the basis of efficiency theory commonly used in economics. The conceptual model is implemented using Data Envelopment Analysis (DEA). Sustainability is measured for a sample of Dutch sugar beet growers. The average technical efficiency was only 50%. A positive correlation was found between technical efficiency and sustainable efficiency. Differences in efficiency among farmers were persistent within and between years. We conclude that there is considerable scope for improving the sustainability of arable farming by better management. 相似文献
434.
435.
Relationships between street characteristics and perceived attractiveness for walking reported by elderly people 总被引:2,自引:0,他引:2
Hieronymus C. Borst Henk M.E. Miedema Sanne I. de Vries Jamie M.A. Graham Jef E.F. van Dongen 《Journal of environmental psychology》2008,28(4):353-361
Walking is important for the health of elderly people. Previous studies have found a relationship between neighbourhood characteristics, physical activity and related health aspects. The multivariate linear regression model presented here describes the relationships between the perceived attractiveness of streets for walking along and (physical) street characteristics. Two hundred and eighty-eight independently living elderly people (between 55 and 80 years old) participated in the study. Street characteristics were assessed along homogeneous street subsections defined as ‘links’. Positively related to perceived attractiveness of links were the following street characteristics: slopes and/or stairs, zebra crossings, trees along the route, front gardens, bus and tram stops, shops, business buildings, catering establishments, passing through parks or the city centre, and traffic volume. Litter on the street, high-rise buildings, and neighbourhood density of dwellings were negatively related to perceived link attractiveness. Overall, the results suggest that three main aspects affect perceived attractiveness of streets for walking, namely tidiness of the street, its scenic value and the presence of activity or other people along the street. The results are discussed within the context of these three aspects. 相似文献
436.
A Comparative Approach for Ranking Contaminated Sites Based on the Risk Assessment Paradigm Using Fuzzy PROMETHEE 总被引:2,自引:0,他引:2
A ranking system for contaminated sites based on comparative risk methodology using fuzzy Preference Ranking Organization
METHod for Enrichment Evaluation (PROMETHEE) was developed in this article. It combines the concepts of fuzzy sets to represent
uncertain site information with the PROMETHEE, a subgroup of Multi-Criteria Decision Making (MCDM) methods. Criteria are identified
based on a combination of the attributes (toxicity, exposure, and receptors) associated with the potential human health and
ecological risks posed by contaminated sites, chemical properties, site geology and hydrogeology and contaminant transport
phenomena. Original site data are directly used avoiding the subjective assignment of scores to site attributes. When the
input data are numeric and crisp the PROMETHEE method can be used. The Fuzzy PROMETHEE method is preferred when substantial
uncertainties and subjectivities exist in site information. The PROMETHEE and fuzzy PROMETHEE methods are both used in this
research to compare the sites. The case study shows that this methodology provides reasonable results. 相似文献
437.
ABSTRACT: Landsat radiance values were processed at two different (single and double) levels of accuracy to estimate chlorophyll a, turbidity, and suspended sediment in Lake Okeechobee, Florida. Both ordinary least square and ridge regression analyses were used to establish a relationship between water quality parameters and Landsat radiance. Radiance measurements made at greater precision (double level) gave a better solution in this application. The ridge regression analysis for double level not only can reduce the total mean square error about 13–20 percent and confidence interval about 6–28 percent as compared to ordinary least square analysis, but it can also change the interpretation of analysis results. 相似文献
438.
C. Michael York 《Journal of the American Water Resources Association》1971,7(5):920-924
ABSTRACT. Elected officials, technical specialists and the public are talking more about “citizen input” into the decision process, and how the people view a given issue or kind of public service. However, problem definition and valid instruments are needed before we can meaningfully predict or understand public attitude relating to a particular issue or concept. The fluoridation of community water supplies was chosen for the present methodological demonstration. This issue achieves a high level of controversy among many public segments [Crain, Katz and Rosenthal, 1969; Davis, 1959; McNeal, 1957]. By 1950, there was widespread endorsement for a national program relating to controlled water fluoridation. Yet, public acceptance of this particular technological advance has not been very high. 相似文献
439.
Jason R. Masoner David I. Stannard Scott C. Christenson 《Journal of the American Water Resources Association》2008,44(3):552-561
Abstract: Research was conducted to develop a method for obtaining floating pan evaporation rates in a small (less than 10,000 m2) wetland, lagoon, or pond. Floating pan and land pan evaporation data were collected from March 1 to August 31, 2005, at a small natural wetland located in the alluvium of the Canadian River near Norman, Oklahoma, at the U.S. Geological Survey Norman Landfill Toxic Substances Hydrology Research Site. Floating pan evaporation rates were compared with evaporation rates from a nearby standard Class A evaporation pan on land. Floating pan evaporation rates were significantly less than land pan evaporation rates for the entire period and on a monthly basis. Results indicated that the use of a floating evaporation pan in a small free‐water surface better simulates actual physical conditions on the water surface that control evaporation. Floating pan to land pan ratios were 0.82 for March, 0.87 for April, 0.85 for May, 0.85 for June, 0.79 for July, and 0.69 for August. 相似文献
440.