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81.
Wim G. M. Bastiaanssen Nagaraja Rao Harshadeep 《Irrigation and Drainage Systems》2005,19(3-4):269-284
Water demands are outstripping supplies in many parts of Asia and causing conflicts, especially as rapidly urbanizing and
industrializing areas compete with more traditional agriculture on alluvial plains near expanding metropolises. The environment
is increasingly being seen as a legitimate and important user of water, often in competition with irrigation, domestic, industrial,
hydropower and community uses of water. Any future scenario requires an improvement in water productivity, especially in agriculture.
Surface and ground water supplies are not well regulated owing primarily to a weak knowledge base, analytical capacity in
addition to a number of traditional institutional, governance, political and other factors. Water policy makers have, therefore,
to work out strategies for integrated water and environmental management, which rely on a proper knowledge base of the basin
hydrological and pollution conditions. Examples from various countries in Asia are elaborated in this paper to demonstrate
how spatially distributed evapotranspiration data from remote sensing, in conjunction with other key data, can help to build
the knowledge base for integrated basin scale water management. Remote sensing is not a solution, but it provides key data
that is difficult to access by conventional data collection methods. 相似文献
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Influence of simulated rainfall on physical properties of a conventionally tilled loess soil 总被引:3,自引:0,他引:3
Wouter Schiettecatte Ke Jin Yuqing Yao Wim M. Cornelis Junjie Lu Huijun Wu Koen Verbist Dianxiong Cai Donald Gabriels Roger Hartmann 《CATENA》2005,64(2-3):209
Rainfall simulations were conducted on a loess derived silt loam soil (Henan province, P.R. China) under conventional tillage. This tillage practice is widespread and involves the turning of the plough layer and the wheat stubble in July (primary tillage), followed by a secondary tillage operation in October. Soil samples were collected and in situ measurements were done before each rainfall simulation in order to analyse soil physical properties after successive simulated rainfall events. The purpose of this study was to determine rainfall induced changes in saturated hydraulic conductivity, bulk density, penetration resistance, water retention and soil erodibility. The results only showed significant differences in soil bulk density and erodibility when applying successive rainfall events. Penetration resistance and water retention (at matric potentials ≤ − 3 kPa) were not significantly affected and soil surface sealing was not observed. This was also confirmed by the infiltration measurements, where no significant differences in saturated hydraulic conductivity were found. From a soil conservation point of view, this study indicated that the primary tillage operation (i.e. ploughing at the beginning of July) is rather disadvantageous: the saturated hydraulic conductivity is not significantly affected, but the soil erodibility is considerably higher in comparison to a consolidated soil. Furthermore, the beneficial effects of the wheat stubble on soil and water conservation are lost by the tillage operation. 相似文献
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van der Sluis AA Dekker M Skrede G Jongen WM 《Journal of agricultural and food chemistry》2004,52(10):2840-2848
There is a great interest in food components that possess possible health-protecting properties, as is the case with flavonoids. Previous research showed that conventional apple juice processing resulted in juices poor in flavonoids and with a low antioxidant activity. This paper shows that it is possible to improve flavonoid content in juice and its antioxidant activity by applying an alcoholic extraction either on the pulp or on the pomace. The levels of flavonoids and chlorogenic acid in enriched juice were between 1.4 (chlorogenic acid) and 9 (quercetin glycosides) times higher than in conventional apple juice. In enriched juice the antioxidant activity was 5 times higher than in conventional apple juice, with 52% of the antioxidant activity of the originating fruits present. The novel processing method had similar effects for three apple cultivars tested (Elstar, Golden Delicious, and Jonagold). The taste and color of enriched juice were different from those of conventional juice. 相似文献
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An Integrative Approach to Value‐Added Planning: From Community Needs to Local Authority Revenue 下载免费PDF全文
The concept of value‐added planning (as part of the Valuing Attractive Landscapes in the Urban Economy, INTERREG IVB North West Europe Project) is introduced in this paper to facilitate integrative planning, focusing on the benefits that use and non‐use green spaces can provide to an urban area. The aim is to stress the need to plan for, and protect, green spaces in urban areas by determining the economic values connected to the green spaces and relate that values to community benefit and local authority revenue. The paper identifies tools that can be used to determine the economic value of green spaces based on the environmental, social, and economic benefits. The first section (value) refers to the social value of green spaces as determined from the public perspective and introduces the workbench method as a tool to assist with participatory planning and capturing of the social benefits of green spaces. The second section (added) refers to the environmental benefits of green spaces and, by means of the Green Credit Tool, introduces ways to ensure the protection of the green resources in an area. The final section (planning) refers to the economic benefit of green space, bringing use values and non‐use values of green spaces together. The paper concludes with an integrative framework for value‐added planning, incorporating all the tools presented in the paper, capturing the social, environmental, and economic benefits of green spaces and relating it to community benefit and local authority revenue. 相似文献
88.
Consumer acceptance of cultured meat is expected to depend on a wide diversity of determinants ranging from technology-related perceptions to product-speciifc expectations, and including wider contextu... 相似文献
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