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城市多媒体综合业务网络
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作者 洪毅 《电缆电视》 1999年第4期5-7,共3页
关键词 多媒体综合业务 有线电视 上区网
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A Method of Catchments Health Assessment under Value-pressure Model and Its Application in Urbanized River Network Area:A Case Study in Shanghai,China
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作者 YUAN Wen YANG Kai 《Chinese Geographical Science》 SCIE CSCD 2011年第1期102-109,共8页
Catchments health assessment is fundamental to effective catchments management. Generally, an assessment method should be selected to reflect both the purpose of assessment and local characteristics. A trial in Shangh... Catchments health assessment is fundamental to effective catchments management. Generally, an assessment method should be selected to reflect both the purpose of assessment and local characteristics. A trial in Shanghai was conducted to test the method for catchments health assessment in urbanized fiver network area. Seven indicators that described four dimensions of river, river network, land use and function, and local feature were used to assess catchments values; while possible change rate of urbanization and industrialization in the next 3 years were chosen for catchments pressure assessment in the value-pressure model. Factors related to catchments classification, indicators measurement and protection priority have been considered in the development strategies for catchments health management. The results showed that value-pressure assessment was applicable in urbanized catchments health management, particularly when both human and catchments had multiple demands. As a result of over 30-year rapid urbanization, more than 70% of Shanghai fiver network area was still in a healthy condition with high catchments values, among them, 39.3% was under high pressure. Poor water quality, simplified river system and weakened local feature of fiver pattern had largely affected catchments health in Shanghai. Lack of long-term monitoring data would seriously restrict the development and validity of catchments health assessment. 展开更多
关键词 catchments health assessment value-pressure model river network area SHANGHAI
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Changes in the Thermal and Hydraulic Regime within the Active Layer in the Qinghai-Tibet Plateau 被引量:7
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作者 XIE Changwei ZHAO Lin +1 位作者 WU Tonghua DONG Xicheng 《Journal of Mountain Science》 SCIE CSCD 2012年第4期483-491,共9页
The change trends of air temperature,precipitation and evaporation from 1999 to 2008 shows that the climate in the Qinghai-Tibet Plateau permafrost region had become warmer.The analysis of the systematic active-layer ... The change trends of air temperature,precipitation and evaporation from 1999 to 2008 shows that the climate in the Qinghai-Tibet Plateau permafrost region had become warmer.The analysis of the systematic active-layer data monitoring network along the Qinghai-Tibet Highway indicated that the active-layer thickness had been increasing and the soil temperature was rising.The soil temperature was rising in winter but not at the end of spring or during the entire summer.With thickening and warming of the active layer,the liquid water content of the active layer had an obvious downward migration and liquid water content in the top horizons decreased,but in the deeper horizons it increased. 展开更多
关键词 Soil temperature Water content Activelayer PERMAFROST Qinghai-Tibet Plateau (QTP)
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