| As an important component part of water resource, karst water has abundant quantity. It becomes the main source of water supply for many cities in the world. The concentrated drainage region of karst water often has big springs, and becomes famous beauty spot. In natural condition, the quantity and quality of karst water changes as the precipitation, evaporation and the movement of the lithosphere varies, but the course is usually slow, or the changes are restorable. These changes don't bring serious sequences to the environment. If human being change and destroy the dynamic balance of karst water system wantonly, the correlative environment and ecologic condition will be deteriorated.As a famous Spring City, "every household has springs" is the most vivid description of Jinan springs. The special hydrogeological conditions, abundant karst water resources and the conformation difference of spring drainage spot form the magnificent natural landscape. In recent decades, with the social and economic development, and the illogical utilization of karst water, the springs' landscape declines gradually.The southern boundary of the Jinan spring area studied in the thesis is determined to be the surface water divide, and the northern one is the Xiaoqing River and the 500-metre limestone roof. The eastern and western boundaries of the Jinan spring area are Dongwu Faults and Bucun Syncline respectively. The total area of the spring area is 2614.9km2. By investigating on the spot, datum collecting and summarizing known production, this paper analyzes quantificationally the cause of discharge declining at a point of physical geography, statistics and sustainable development theory. Then, this paper forecasts the macro-trend of spurting of Jinan spring groups with correlative model, and puts forward the countermeasures aiming at "spring problem". The main contents are as follows:1. Introduction.The significance and purpose of choosing this subject, and achievement home and abroad in this field are introduced. The achievement of predecessors' studies on the Jinan spring groups is summed up.2. Sketchy circumstances in the studied area.The scope of the studied area is defined. The physical geographical environment, hydrogeological conditions and the causes of formation of the Jinan spring groups are introduced.3. The dynamic change of spring groups spurting.In historical period, the hydrologic state of Jinan spring groups had been steady all through. Since 1950's, the process of Jinan springs spurting can be divided into several periods including perennial spurting period, interim, declining period and artificial controlling period. Furthermore, the Jinan spring groups discharge changes seasonally with alteration ofprecipitation.4. The influence factors and the causes of declining of Jinan spring groups.During 1965-1989, the reduction of precipitation, which had been controlling the declining trend of the spring groups' discharge, was the major factor of the declination of the spring groups' discharge. In recent decades, human activity plays an increasing role in the declination of the spring groups' discharge. Over- exploitation of karst water and illogical distribution of water source region enlarge the declining grads. In 1990's, the quantity of exploitation reached the highest level in history, and this pricked up the cutting-off phenomenon. The landuse change caused by the development of Jinan city altered the hydrological process to a certain extent, increased runoff volume and shortened the time of concentrated flow. These changes decrease the recharge to karst water, and induce the declination of the spring groups' discharge. Moreover, the establishment of reservoirs in southern mountain region influenced the natural connection between recharge and drainage of karst water system, which accelerates the declination of Jinan spring groups' discharge.5. The macro-trend forecasting of Jinan spring groups' spurting.The threshold regressive model based on ge...
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