THE APPRAISAL AND RESEARCH ON THE ENVIRONMENTAL ENGINEERING GEOLOGY OF FUZHOU SECTION OF THE LOWER MINJIANG RIVER

Environmental geological and geomorphological conditions along a river are the important factors affecting the construction and development of an alongshore city and its environmental features and are also the backgrounds determining the environmental quality and functions of the cities along the river and the whole natural environment.Therefore,investigation of environmental geology and geomorphology along the river is of important theoretical and practical significance not only in improving the environmental quality and capacity of the city on the river.Take the Fuzhou section of Minjiang River as an example,in this paper a brief account and analysis of hydrodynamic conditions and change of hydrodynamic factors in time and space are taken.We have analyzed and studied the geomorphologic and geological characteristics of the southern and northern ports of Fuzhou section of Minjiang River and their evolutional tendency;the interaction of all kinds of human engineering constructions along river and the patterns and strength of geological effect and geomorphologic environment of the southern and northern ports. The results show that amount of water flow in northern port of Mingjiang River riverbed increases year after year,water level drops and sand content decreases every year;amount of water flow in southern post of Minjiang River decreases year after year,but water level rises.All kinds of human activities such as engineering construction,intensify the difference in amount of runoff and water level in the southern and northern ports of Minjiang River,promote and strengthen the erosive effect on northern port and siltation effect on southern port.and make the geological and geomorphologic environments for southern and northern ports of Minjiang River develop in an unstable direction.The deterioration of geological and geomorphologic environments for the southern and northern ports of Minjiang river reflects the result of all kinds of unregular human activities,such as engineering construction,and hence the stability and security of the engineering projects which have been built or in building or in planning to build are and will be lost damaged greatly.