Formulation Of River Health Index And Its Application To Downstream Yellow River

Rivers are great creators. They offered habitats for myriad wildlife's sustenance, and provided cradles for ancient civilizations'booming. The concept of"river health"is now gaining concerns from various aspects of the society, including the academy, the administration and the public. One of the main objectives of today's river management is to maintain and improve the river health while the economy is growing rapidly. Therefore it is of great significance to theoretically research the river health's concept and work out methods to assess it, which will be s a useful tool of river management.The river health's definition and description at home and abroad were introduced, analyzed and summarized. The essence of river health is the harmony between human and nature. To meet this goal it is necessary to conduct a dynamic assessment of the health conditions of rivers systems undergoing both natural and artificial stresses, study the trend of river systems'development and bring forward strategies of managements. The purpose of management is to eliminate unharmonious factors that affect river health and bring the river onto a healthy track. Merits and shortcoming of traditional assessment methods were evaluated through analysis of the development of the concept of river health, and a formula to calculate the river health's index was brought forth, based on which criteria to classify rivers'health conditions was also set up. The formula to calculate river health index was adopted to estimate the river health conditions on several locations of the lower Yellow River including the hydrological stations of Huayuankou, Gaocun and Lijin from the fiftieth to ninetieth decade last century. Several strategies to improve the health condition of the lower Yellow River were brought forward. The effectiveness of some of these strategies that have already been adopted was validated.The formulation of river health index proposed by this paper has been applied to the downstream of Yellow River. The river health index equation can diagnose the health condition of lower Yellow River with relatively few data. It shows good accordance with the field data, good practicality and good operability. The proposals and results of this paper can serve as a good consultive role for the evaluation of the effectivity of the river health and river management measures.