中文摘要：

为探讨人为来源的硫酸和硝酸进入地下河系统后产生的水．岩作用时空差异，以受城镇排污和工农业活动影响的广西南丹县里湖地下河流域为研究对象，分别于2014年5月、10月及2015年1月、7月对里湖地下河水化学进行监测并分析其δ13CDIC组成，结果表明：①里湖地下河流域为HCO3-Ca型，受控于碳酸盐岩的自然风化溶解和人为产生的城镇污水、工业废水和农用肥料的影响，各离子浓度在旱季大于雨季，空间上从上游到下游整体呈现波动下降的趋势；②地下水[Ca2＋ ＋Mg2＋]／[HCO3-]当量比值在1．12-1．56之间，[SO42- ＋NO3-]／[HCO3]比值在0．11-0．50之间，揭示硫酸、硝酸参与了水．岩作用；③根据水化学方法计算得出碳酸溶蚀碳酸盐岩的比例介于28．04％～78．55％之间，平均为50．01％，溶解能力最强为下游的小龙洞处，季节上，在2014年5月其溶蚀能力均较弱，受多种因素影响，在流域的不同区域，碳酸溶蚀的最大强度出现在不同季节；硫酸和硝酸溶蚀碳酸盐岩的比例介于21．45％～71．96％之间，平均为49．71％，在农业活动的影响下，其溶蚀能力最强出现在2014年5月，受人类活动强度和水体自净作用的综合影响，其溶蚀强度总体上表现为中游农业活动区域〉上游城镇和工业排污区域〉下游人为活动较少干扰区域；④地下水δ3CDIC分布在-10．74‰～-4．34‰之间，平均为-7．36‰，由δ13CDIC估算出的碳酸溶解碳酸盐岩形成的DIC的比例在34．32％-84．96％之间，2014年5月的农耕季节所占比例较低，与水化学方法估计出的结果一致，共同指示了农业活动对碳酸溶解碳酸盐岩的干扰。空间上，在流域水体C02脱气和水生植物代谢过程的扰动下，两种估算结果的响应受到干扰，还应根据具体情况，将水化学划分方法和同位素混合比例方法相结合，相互检验。

英文摘要：

To explore the temporal and spatial variation patterns of water-rock interaction caused by sulphuric acid and nitric acid which were input into the groundwater system by human activities, several groundwater samples, collected in May and October, 2014 and January and July, 2015 in Lihu were monitored to analyze the chemical composition of conventional water and the characteristics of δ13CDIC. The results show that： （1） the groundwater is mainly characterized by HCO3-Ca chemical composition, effected by the weathering of carbonate rocks and anthropogenic discharge of domestic sewage, industrial waste water and agricultural fertilizer, the ion concentrations in the dry season are higher than those in the rainy season and show a decreasing trend from the upstream to the downstream; （1） equivalent ratios of [Ca2 ＋ Mg2＋]/[HCO3-] lie between 1.12 and 1.56, and those of [SO42- ＋ NO3-]/[HCO3-] stand between 0.11 and 0.05, revealing that the sulphuric acid and nitric acid have taken part in water-rock interaction; （2） integrated water hydrochemistry data, using the hydration method, were calculated, indicating that the proportions of carbonic acid dissolving carbonate rocks range between 28.04% and 78.55% with an average of 50.01%, the proportions are greater in May, 2014, and in different regions, the maximum strength of carbonate dissolution occurs in difference seasons. In space, the carbonic acid weathered carbonate rocks have played a key role in the downstream Xiaolong Cave; the proportions of sulphuric acid and nitric acid dissolving carbonate rocks vary from 21.45% to 71.96% with an average of 49.71%. Disturbed by agricultural activities, the dissolution of carbonate rocks by sulphuric acid and nitric acid is obvious in May, 2014. Under the comprehensive influence of human activities and the self purification of groundwater, the dissolution intensity of carbonate rocks decreases in order of midstream agricultural region, upstream urban region and industrial region, and downstream region which