Assessing environmental flows （e-flows） for urban rivers is important for water resources planning and river protection, Many e-flow assessment methods have been established based on species＇ habitat pro- vision re...Assessing environmental flows （e-flows） for urban rivers is important for water resources planning and river protection, Many e-flow assessment methods have been established based on species＇ habitat pro- vision requirements and pollutant dilution requirements, To avoid flood risk, however, many urban rivers have been transformed into straight, trapezoidal-profiled concrete channels, leading to the disappearance of valuable species, With the construction of water pollution-control projects, pollutant inputs into rivers have been effectively controlled in some urban rivers, For these rivers, the e-flows determined by tradi- tional methods will be very small, and will consequently lead to a low priority being given to river pro- tection in future water resources allocation and management, To more effectively assess the e-flows of channelized urban rivers, we propose three e-flow degrees, according to longitudinal hydrological con- nectivity （high, medium, and low）, in addition to the pollutant dilution water requirement determined by the mass-balance equation, In the high connectivity scenario, the intent is for the e-flows to maintain flow velocity, which can ensure the self-purification of rivers and reduce algal blooms; in the medium connectivity scenario, the intent is for the e-flows to permanently maintain the longitudinal hydrological connectivity of rivers that are isolated into several ponds by means of weirs, in order to ensure the exchange of material, energy, and information in rivers; and in the low connectivity scenario, the intent is for the e-flows to intermittently connect isolated ponds every few days （which is designed to further reduce e-flows）, The proposed methods have been used in Shiwuli River, China, to demonstrate their effectiveness, The new methods can offer more precise and realistic e-flow results and can effectively direct the construction and management of e-flow supply projects,展开更多
Based on the retrospection of researches on carrying capacity, this article reviewed systematically the research progresses on carrying capacity of relative resources (CCRR). Then the viewpoint was put forward that CC...Based on the retrospection of researches on carrying capacity, this article reviewed systematically the research progresses on carrying capacity of relative resources (CCRR). Then the viewpoint was put forward that CCRR is not an appropriate method of appraising the regional sustainability, but a sound way to obtain cognition for coordinating spatial location and flow of population and economy. However, as the most popular computing method of CCRR, the Weighting Linear Sum Model is defective in the random of weight choice and the neglect of matching among different resources. Therefore, this article established the Geometric Model on CCRR based on modifying Weighting Linear Sum Model, which can be used to appraise regions where resources are close matching. Employing the Geometric Model, the article empirically analyzed the population and economic CCRR in Hubei Province from 1978 to 2006. The result indicates that the population in Hubei Province is overloading while the economic carrying capacity is abundant compared to the whole country, and the economic insufficiency restricts the population carrying capacity. In the future, Hubei Province will become one of the core developing zones which are characterized by economic conglomeration.展开更多
It was found based on the history of acupuncture and records in ancient medicine writings that acupuncture manipulation originated from ancient times,formed in Pre-Qin and Han Dynasties（from the 21 century BC to220 A...It was found based on the history of acupuncture and records in ancient medicine writings that acupuncture manipulation originated from ancient times,formed in Pre-Qin and Han Dynasties（from the 21 century BC to220 AD）,slowly developed in Jin,Sui and Tang Dynasties（256 AD to 907 AD）,and gradually flourished in Song,Jin,and Yuan Dynasties（906 AD to 1368 AD）.It experienced prosperity and decline in the Ming and Qing Dynasties（1368 AD to 1912 AD）,tortuously developed in modern times,and is widely studied in nowadays.展开更多
文摘Assessing environmental flows （e-flows） for urban rivers is important for water resources planning and river protection, Many e-flow assessment methods have been established based on species＇ habitat pro- vision requirements and pollutant dilution requirements, To avoid flood risk, however, many urban rivers have been transformed into straight, trapezoidal-profiled concrete channels, leading to the disappearance of valuable species, With the construction of water pollution-control projects, pollutant inputs into rivers have been effectively controlled in some urban rivers, For these rivers, the e-flows determined by tradi- tional methods will be very small, and will consequently lead to a low priority being given to river pro- tection in future water resources allocation and management, To more effectively assess the e-flows of channelized urban rivers, we propose three e-flow degrees, according to longitudinal hydrological con- nectivity （high, medium, and low）, in addition to the pollutant dilution water requirement determined by the mass-balance equation, In the high connectivity scenario, the intent is for the e-flows to maintain flow velocity, which can ensure the self-purification of rivers and reduce algal blooms; in the medium connectivity scenario, the intent is for the e-flows to permanently maintain the longitudinal hydrological connectivity of rivers that are isolated into several ponds by means of weirs, in order to ensure the exchange of material, energy, and information in rivers; and in the low connectivity scenario, the intent is for the e-flows to intermittently connect isolated ponds every few days （which is designed to further reduce e-flows）, The proposed methods have been used in Shiwuli River, China, to demonstrate their effectiveness, The new methods can offer more precise and realistic e-flow results and can effectively direct the construction and management of e-flow supply projects,
基金National Natural Science Fundation of China (Grant No:40671062)
文摘Based on the retrospection of researches on carrying capacity, this article reviewed systematically the research progresses on carrying capacity of relative resources (CCRR). Then the viewpoint was put forward that CCRR is not an appropriate method of appraising the regional sustainability, but a sound way to obtain cognition for coordinating spatial location and flow of population and economy. However, as the most popular computing method of CCRR, the Weighting Linear Sum Model is defective in the random of weight choice and the neglect of matching among different resources. Therefore, this article established the Geometric Model on CCRR based on modifying Weighting Linear Sum Model, which can be used to appraise regions where resources are close matching. Employing the Geometric Model, the article empirically analyzed the population and economic CCRR in Hubei Province from 1978 to 2006. The result indicates that the population in Hubei Province is overloading while the economic carrying capacity is abundant compared to the whole country, and the economic insufficiency restricts the population carrying capacity. In the future, Hubei Province will become one of the core developing zones which are characterized by economic conglomeration.
基金Supported by National Natural Science Foundation of China:81001551
文摘It was found based on the history of acupuncture and records in ancient medicine writings that acupuncture manipulation originated from ancient times,formed in Pre-Qin and Han Dynasties（from the 21 century BC to220 AD）,slowly developed in Jin,Sui and Tang Dynasties（256 AD to 907 AD）,and gradually flourished in Song,Jin,and Yuan Dynasties（906 AD to 1368 AD）.It experienced prosperity and decline in the Ming and Qing Dynasties（1368 AD to 1912 AD）,tortuously developed in modern times,and is widely studied in nowadays.
