昆明盆地地下水水质水位长序列数据特征分析

通过对昆明盆地，特别是主城区长序列水质水位监测数据对比分析，采用水文地质法、数据统计法、Piper和Matlab软件建立模型进行水质水位动态特征和变化趋势分析研究。昆明盆地地下化学类型以HCO3-Ca和HCO3-Ca·Mg型为主。孔隙水超标项以Mn、NH地下水监测; 水质; 水位; 趋势分析; 昆明盆地国家重点研发计划项目(2016YFC0502502)；通过对昆明盆地,特别是主城区长序列水质水位监测数据对比分析,采用水文地质法、数据统计法、Piper和Matlab软件建立模型进行水质水位动态特征和变化趋势分析研究。昆明盆地地下化学类型以HCO₃-Ca和HCO₃-Ca·Mg型为主。孔隙水超标项以Mn、NH₄⁺、 NO₃^-、COD为主;岩溶水超标项以Mn、NH₄⁺、F为主;近年来超标物项目趋于复杂,出现I、SO₄^2-、As、Cd等有毒有害和有机物超标,水质变化原因为工业和生活污染加剧。对地下水位20年长序列动态变化特征和趋势研究表明,昆明盆地地下水位年际变化主要受工农业生产、开采量和工程活动等影响,孔隙水2002—2009年呈下降趋势,2009年后总体呈上升趋势;岩溶水2002—2012年呈下降趋势,2012年后总体呈上升趋势;翠湖等5个降落漏斗区地下水位回升趋势较为显著,主要与昆明市限制地下水开采、封填地下水开采井的措施...

Characteristics of long series data of groundwater quality and level in Kunming basin

Kunming basin is a representative of karst faulted basin, with a basin bottom area of 846.19 km2 and a fluctuation of 1-82 m averaging at 19 m. With the city development, Kunming has gradually become one of the megacities in China. However, as the center of intensive human settlements and activities, the contradiction between human and land is prominent, and the problems of resources and environment are serious. Since the 1960s, the dynamic monitoring of groundwater in the urban and suburban areas of Kunming has been carried out in a comprehensive and systematic manner. In this study, hydrogeology method, data statistics method, Piper and Matlab software were used to establish models to analyze the dynamic characteristics and change of water quality and water level, based on the comparative analysis of monitoring data of water quality and level in Kunming basin, especially in the main urban area. The main underground chemical types of Kunming basin are HCO3-Ca and HCO3-Ca·Mg. In recent years, with the gradual increase of Na+ + K+ and ${\rm{SO}}_4^{2-} $ +Cl, the hydrochemical types have also gradually been increasing and become more complex. According to the water quality evaluation, the groundwater quality in Kunming basin has generally shown a downward trend in recent 15 years. The pore water quality is mainly of Class IV and Class V, and the proportion of Class V water has increased rapidly, from 30.2% to 62.5%. The bedrock water quality is mainly of Class III and Class IV. The proportion of Class IV water and Class V water has risen rapidly from 11.1% and 8.6% to 33.3% and 26.7%, respectively. Mn, NH$_4^{+}$, ${\rm{NO}}_3^{-}$ and COD are the main items exceeding permitted levels in pore water. Mn, NH$_4^{+}$ and F are the main items exceeding permitted levels in karst water. In recent years, I, ${\rm{SO}}_4^{2-}$, As, Cd and other toxic, harmful and organic substances have exceeded permitted levels, showing a compex tendency. The reason for the change of water quality is the intensification of industrial and domestic pollution. The results show that the interannual variation of groundwater level in Kunming basin is mainly affected by industrial and agricultural production, mining amount and engineering activities, and pore water decreased from 2002 to 2009, but increased after 2009. Karst water showed a downward trend from 2002 to 2012, and an upward one after 2012. The groundwater levels of Puji-Liangjiahe, Beijiaochang, the urban area of Kunming, Jinmasi-Guanshang and other water-rich blocks have risen significantly. The rising trend of groundwater levels in Cuihu, Heilongtan, Beijiaochang, Majie, Heilinpu and other five falling funnel areas is significant, which is closely related to the measures of restricting groundwater exploitation and sealing groundwater exploitation wells in Kunming City. Based on the dynamic analysis of water quality and water level, countermeasures and strategies to protect groundwater should be proposed through enhancing administrative management, strengthening the investigation, evaluation and monitoring of basic groundwater environment, and furthering the research on technology of preventing groundwater pollution.