The over-exploitation of shallow groundwater in the People’s Victory Canal irrigation area has led to the continuous decline in the groundwater level. The formation of a groundwater drawdown cone has changed the original runoff conditions and hydrochemical environment. Based on the groundwater data in the irrigated area from 1996 to 2022, multivariate statistical analysis, traditional hydrochemical methods, and inverse geochemical modeling were used to reveal the impact of the formation of the groundwater depression cone on hydrochemical evolution. The results show that the formation of the groundwater depression cone near the central area in 2003 changed the direction of the canal head flowing to the northwest area, making the groundwater flow from the canal head and the northwest area to the central area. The change in the hydrodynamic fields also caused the groundwater with high salinity in the northwest region to flow to the funnel area, and the ion concentration of groundwater along the pathway area to increase. The groundwater type in the runoff area changes, gradually evolving from Group 1 to Group 2 groundwater. Analysis of the hydrochemical characteristics of groundwater in the runoff area for many years shows that after the formation of the central funnel area in 2003, the groundwater with high ion in the northwest area flows to the funnel area, and the correlation between total dissolved solids and ions in the groundwater along the way is significantly enhanced. The inverse geochemical modeling shows that the main water–rock action along the runoff direction is the dissolution of halite and gypsum. In addition, the study area has a strong cation exchange reaction.
Climate change and human activities have intensified the imbalance between water supply and demand in the Shule River Basin. Prominent issues such as groundwater over-exploitation and insufficient ecological base flow have significantly constrained the high-quality development of the region. An evaluation system was developed comprising 20 indicators across four subsystems: water resources, society, economy, and ecosystems. The entropy weighting method was employed to determine the weights of each indicator. The coupling coordination degree of the water resource–society–economy–ecosystem system from 2003 to 2022 was assessed using a coupling coordination degree model. Network analysis was applied to evaluate the correlation and connectivity among indicators. A barrier diagnostic model based on indicator deviation was further constructed to identify key constraints within the system. The results showed that the overall coordination degree of the coupled system increased from 0.217 in 2003 to 0.409 in 2022, shifting from a moderately uncoordinated state to a weakly coordinated one. However, the coordination level remained low due to fluctuations in the water resource subsystem. The ecological and economic subsystems functioned as critical coupling hubs, while strong negative interactions within the water resource subsystem emerged as major constraints to coordinated development. Long-term dominant barriers included the proportion of water used for ecological and agricultural purposes, as well as per capita food production. After 2019, water resource-related indicators, such as per capita water availability and water production modulus, showed a marked increase in obstruction levels, highlighting the persistent challenges posed by water scarcity and inefficient utilization.