Investigating the hydraulic connectivity of a complex karst aquifer system is an important research topic for sustainable operation and optimization layout of karst groundwater exploitation and recharge. However, the identification of preferential sites of recharge and exploitation is usually subject to regional hydrogeology conditions and the mechanisms of recharge and exploitation. The conventional research methods of hydraulic connectivity often have some limitations. In this study, we developed an improved grey amplitude relation model to explore the hydraulic connectivity in Jinan spring catchment and presented a quantized evaluation index water table fluctuation relation degree (WTFRD) using karst groundwater table data in Western Jinan and Jinan spring groups from 2014 to 2017. Results showed that the total WTFRD was 0.854 between Western Jinan and Jinan spring groups when the external distraction for karst groundwater table was the smallest, which was in high relation degree grade. Meanwhile, the change rules of karst groundwater table in the two sites were basically the same. Accordingly, a high connectivity occurred between the two karst aquifers from a statistical perspective, and further illustrated that Western Jinan could be selected as preferential experiment sites. A comprehensive case in Jinan spring catchment indicated that the WTFRD provided a preliminary idea to investigate hydraulic connectivity quantitatively. This method could be considered as a pre-study of the conventional experiments to form a high-efficiency and low-cost combined method, which has great potential and merits further study.

As an important part of urban water system, urban landscape water plays a significant role in the improvement of urban ecological effect, such as adjusting regional climate, increasing water vapor content and reducing urban heat land effect. At present, the pattern of landscape water has a lot of research findings, but quantitative analysis of the impact on ecological function of urban landscape water is too little. This paper took hydrologic station upstream in Huangtaiqiao in Jinan city as study area and respectively compared ecological effect of landscape water with land surface on adjusting regional temperature from two periods of annual and summer evaporation. The result shows that landscape water does better in this aspect. So it is essential to pay extraordinary attention to reasonably planning landscape water of land use in the future in order to give full play to its ecological effect.

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With rapid urbanisation, a karst water recharge area of the Jinan spring catchment was damaged. Thus, managed aquifer recharge projects were built in the western Jinan spring catchment to protect the water supply of the spring. Yufuhe River was selected as the study area to compute the effective recharge rate into karst aquifers. This strong seepage zone has a large gradient and undergoes a specific hydrogeological condition in which two strata of a gravel layer and limestone change to three strata of gravel, impermeable clay shale and limestone at the open window of the karst aquifers. A hydraulic model called HEC-RAS was applied to simulate the river stage, and a numerical groundwater model called HYDRUS-3D was adopted to simulate the groundwater mound dynamics and estimate river flow seepage into the aquifers. The effective recharge rates are 64.9%, 65.2% and 68.1% when the buried depths of groundwater are 40, 30 and 25 m. An analysis of the electric conductivity, water table, temperature and water volume data found an effective recharge rate of 68.3%. Results of field monitoring confirmed the accuracy of the numerical simulation and showed that most of the recharged water in the study reach can be effectively recharged into the karst aquifers.

With the requirement of the construction of water eco-civilization, the urban development in Northern China have paid more attention to the construction of landscape water. The spatial pattern of landscape water directly affects urban ecological function, but now, the study of this field is too little. Four typical distribution of landscape water area in Jinan, Weifang, Linyi and Jining of Shandong province, China were selected as study areas, four appropriate spacial indexes, such as suitable ratio of water surface area, shape index, evenness index and dispersity index were adopted and the corresponding standard for each index were determined to compare four cities’ landscape pattern with comprehensive analysis. So it is essential to reasonably plan landscape water area of land use in the future in order to give full play to its ecological effect in cities.