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151.
George F. Antonious Eric T. Turley Regina R. Hill John C. Snyder 《Journal of environmental science and health. Part. B》2013,48(4):299-304
Organic matter and nutrients in municipal sewage sludge (SS) and chicken manure (CM) could be recycled and used for land farming to enhance fertility and physical properties of soils. Three soil management practices were used at Kentucky State University Research Farm, Franklin County, to study the impact of soil amendments on kale (Brassica oleracea cv. Winterbar) and collard (Brassica oleracea cv. Top Bunch) yields and quality. The three soil management practices were: (i) SS mixed with native soil at 15 t acre?1, (ii) CM mixed with native soil at 15 t acre?1, and (iii) no-mulch (NM) native soil for comparison purposes. At harvest, collard and kale green plants were graded according to USDA standards. Plants grown in CM and SS amended soil produced the greatest number of U.S. No. 1 grade of collard and kale greens compared to NM native soil. Across all treatments, concentrations of ascorbic acid and phenols were generally greater in kale than in collards. Overall, CM and SS enhanced total phenols and ascorbic acid contents of kale and collard compared to NM native soil. We investigated the chemical and physical properties of each of the three soil treatments that might explain variability among treatments and the impact of soil amendments on yield, phenols, and ascorbic acid contents of kale and collard green grown under this practice. 相似文献
152.
George Foy 《Environmental management》1990,14(6):771-778
The core requirement of sustainability is that current economic activities should not result in an excessive burden on future
generations. This criterion is general enough to imply different decision rules for the preservation of environmental assets.
Neoclassical economics does not have a sustainability criterion for environmental assets independent of the intertemporal
efficiency criterion, which allocates environmental and man-made capital based on projected monetary benefits and costs. This
criterion is examined in terms of the feasibility of valuing the benefits of environmental assets, the substitution possibilities
between natural and man-made capital, and the ethical grounds for using efficiency as the sole determinant of the allocation
of environmental assets. An alternative ecological sustainability criterion is the preservation of safe minimum levels of
environmental assets in physical terms rather than the dollar value of a composite of natural and man-made capital. Safe minimum
standards for environmental assets constrain the efficiency criterion in order to ensure the sustainability of economic systems.
It is argued that the ecological approach to sustainability should limit the economic approach for decisions involving the
allocation of environmental assets. 相似文献
153.
154.
Dr Abdal‐Majeed I. Daghistani BA MSc PhD MRTPI 《Journal of Environmental Planning and Management》1991,34(1):2-9
The towns and cities of Saudi Arabia have been subjected to sustained growth pressures since the transformation of the country's economy following the discovery of oil in the Eastern Province of the Kingdom. The rapid growth which has been experienced has created major problems for the central and local government agencies responsible for planning and managing urban growth. The experience of Jeddah, one of the major cities in Saudi Arabia, is described and the problems of planning and managing its growth are analysed. Weaknesses relating to the structure of the planning system are identified, as are major difficulties in relation to the quality and quantity of professional staff. Recent attempts to improve the operation of the planning system are described and evaluated. 相似文献
155.
Thomas Carlisle George Mulamoottil Bruce Mitchell 《Journal of the American Water Resources Association》1991,27(3):419-427
ABSTRACT: The objective was to survey individuals from different interest groups in Ontario to ascertain attitudes towards the use of artificial wetlands for stormwater management and to provide waterfowl habitat. In total, 166 questionnaires were distributed and 124 cempleted returns were received. The results of the survey show that the provision of wetlands as waterfowl habitats in the context of stormwater impoundments is severely limited and is not considered an important management option. The overwhelming rejection of this integrated approach seems to be due to a lack of understanding and its comparative newness. Some of the perceived problems and concerns could be addressed by improvements in the design of the artificial wetlands. The design and implementation of an artificial wetland prototype as part of an education program in Ontario is recommended. A few research opportunities also are outlined. 相似文献
156.
ABSTRACT: Geographic Information Systems (GIS) were used to assess the relationships between land use patterns and the physical habitat and macroinvertebrate fauna of streams within similar sized watersheds. Eleven second or third order watersheds ranging from highly urbanized to heavily forested were selected along Lake Superior's North Shore. Land use patterns within the watersheds were quantified using readily available digital land use/land cover information, with a minimum mapping resolution of 16 ha. Physical habitat features, describing substrate characteristics and stream morphology, were characterized at sample points within each stream. Principle component and correlation analyses were used to identify relationships between macroinvertebrates and stream physical habitat, and between habitat and land use patterns. Substrate characteristics and presence of coarse woody debris were found to have the strongest correlations with macreinvertebrate assemblage richness and composition. Agricultural and urban land use was correlated with substrate characteristics. Algal abundance, associated with macroinvertebrate compositional differences, was correlated with housing density and non-forest land covers. The use of readily available spatial data, even at this relatively coarse scale, provides a means to detect the primary relationships between land use and stream habitat quality; finer-resolution GIS databases are needed to assess more subtle influences, such as those due to riparian conditions. 相似文献
157.
Dr. Hana L. Ayala 《Environmental management》1987,11(2):141-147
We are witnessing a growing concern with the global dimension of many environmental issues, reflected in the increase in the number and significance of international environmental organizations. Yet there is no internationally applicable strategy for environmental research which is management oriented. A new type of research policy, which integrates ideas derived from environmental and human ecology, is required in order to deal with cultural and ecological diversity and their interactions as reflected in the ecology of landscapes. The newly defined concept of environmental health is proposed to fill this gap. This concept integrates the latest developments in landscape evolutionary ecology and environmental health, bringing out a conflict between making the environment conducive to human health and increasing the available options for supporting the essential biological and ecological processes of the environment. Lessons derived from the evolution of human environments are used in order to illustrate how health may become un umbrella for developing an environmental research policy, which could also serve as a catalyst for international environmental projects. 相似文献
158.
When bentonite or other clays and zeolites are modified with quaternary amines, they become organophilic. Such modified bentonites are used to remove mechanically emulsified oil and grease, and other sparingly soluble organics. If the organoclay is granulated, it is placed into a liquid phase carbon filter vessel to remove FOGs (Free Oil and Grease) and chlorinated hydrocarbons. In this application the clay is mixed with anthrazite to prevent early plugging of the filter by oil or grease droplets. In batch systems a powdered organoclay is employed. Organoclay removes mechanically emulsified oil and grease at 5–7 times the rate of activated carbon, or 50% of its dry weight. Oil and grease and other large sparingly soluble chlorinated hydrocarbons and NOMs (Natural Organic Matter) blind the pores of activated carbon (and ion-exchange resins), reducing its effectiveness significantly. It is therefore economically advantageous for the end user to prepolish the water before it enters carbon vessels. Operating costs can often be reduced by 50% or more. 相似文献
159.
In many locations, regulatory agencies do not permit tree planting above landfills that are sealed with a capping clay, because
roots might penetrate the clay barrier and expose landfill contents to leaching. We find, however, no empirical or theoretical
basis for this restriction, and instead hypothesize that plant roots of any kind are incapable of penetrating the dense clays
used to seal landfills. As a test, we excavated 30 trees and shrubs, of 12 species, growing over a clay-lined municipal sanitary
landfill on Staten Island, New York. The landfill had been closed for seven years, and featured a very shallow (10 to 30-cm)
soil layer over a 45-cm layer of compacted grey marl (Woodbury series) clay. The test plants had invaded naturally from nearby
forests. All plants examined—including trees as tall as 6 m—had extremely shallow root plates, with deformed tap roots that
grew entirely above and parallel to the clay layer. Only occasional stubby feeder roots were found in the top 1 cm of clay,
and in clay cracks at depths to 6 cm, indicating that the primary impediment to root growth was physical, although both clay
and the overlying soil were highly acidic. These results, if confirmed by experimental research should lead to increased options
for the end use of many closed sanitary landfills. 相似文献
160.