Abstract:In the east of Dawenkou basin, 25km southwest of Tai'an city, the largest karst spring group named as Shangquan sping group is exposed in the southern foot of Taishan Mountain. Through exploration, the boundary of Shangquan spring area is clear and controlled by fault structure and stratum lithology. The exposed surface of CambrianOrdovician carbonate rock intercalated with clastic rock in the hilly area of Yunting mountain and Nanshan area in the east of the spring area receive direct infiltration of atmospheric precipitation. The Western Piedmont inclined plain is shallow covered or semi exposed. In addition to the infiltration of atmospheric precipitation, it also receives the leakage of Nanliu river and the seasonal irrigation of Shengli reservoir. The effect is obvious. The annual average recharge resources of atmospheric precipitation are about 1.9million m3, the leakage recharge resources of Nanliu river are about 2.59 million m3, the recharge resources of agricultural irrigation seepage water are about 520000m3, the total amount is about 5.01 million m3. After deducting the discharge of 340000m3 of upper spring group, the mining amount of industrial and agricultural water and domestic water is about 2.22 million m3, the remaining 2.45 million m3 is gradually discharged into the downstream runoff of spring field in Quaternary loose rock pore aquifer. In order to protect the landscape resources of Shangquan spring group, based on the principle of "looking first and then using", it is forbidden to increase the exploitation of karst groundwater in the upstream of the spring group. Wells can be properly arranged in the limestone distribution area of the hidden Cambrian Chaomidian formation and Zhangxia formation in the downstream of the spring group, so as to seize part of the runoff and discharge resources, which will not have a great impact on the spring group gushing.
