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The People's Victory Canal Irrigation Area is a large gravity irrigation area in the middle and lower reaches of the Yellow River. Groundwater hydrochemistry is controlled by geochemical weathering, precipitation, irrigation from the Yellow River diversion, and artificial exploitation. The Piper diagram, hierarchical cluster analysis, Gibbs diagram, and ion proportion coefficient were applied to improve our understanding of the hydrogeochemical evolution. Our results indicated that groundwater ion concentration has prominent spatial zonation characteristics in the study area. The groundwater ion components in the low salinity area are mainly a result of silicate and carbonate weathering, with the major hydrochemical type being HCO3·Cl–Na·Mg and HCO3–Na·Ca. The soil salt content in the low salinity area is low. The main effect of precipitation on groundwater chemical composition is a reduction in groundwater ion concentration by recharge. The groundwater ion concentration near the canal is similar to the Yellow River water. The groundwater ionic components in the high salinity area are mainly affected by weathering, silicate dissolution, and evaporative salt rocks. The water chemical type is SO4·Cl–Na·Mg. Expectedly, the soil salt content is high in the high salinity area. The Yellow River recharge decreased the ion concentration of groundwater near the canal. In addition, the groundwater exploitation increase results in a change in the flow field, affecting the local groundwater chemistry. The groundwater ion concentration increases as the groundwater flow from the high salinity area to the low salinity area. In contrast, the groundwater ion concentration in the high salinity area decreases. We further discuss these results in the context of the complex influence of precipitation, Yellow River diversion irrigation, and artificial exploitation on the hydrogeochemical evolution. [ABSTRACT FROM AUTHOR]

A comparison between gross irrigation water use (GIWU) in fields and allocated irrigation water rights amount (AIWA) is critical for evaluating any system of water rights allocation. GIWU in fields under different precipitation probabilities has been rarely calculated and compared with AIWA using households' survey data. This study developed a method for calculating the GIWU of crops under different precipitation probabilities using field survey data from 391 households and the monitoring data of wells in Chengan County, China. AIWA was compared with the calculated GIWU and irrigation quota. Results showed that AIWA is too small to satisfy the GIWU of the principle crops. The GIWU of main cropping patterns under a precipitation probability of 75% was curtailed between 43 and 77% to fulfill AIWA. AIWA cannot support any cropping patterns when precipitation is lower than the precipitation percentile of 75%. In this condition, farmers are restricted to planting apples, cotton, and sweet potatoes. The uncertainty in precipitation was not fully considered, and the participation of farmers in water rights allocation in Chengan County was limited, which may adversely influence the income and food security of farmers. [ABSTRACT FROM AUTHOR]

The compensation mechanism for agricultural water transfer (CMAWT) is an important method for reducing or eliminating the negative effects of agricultural water transfer. Summarizing global CMAWT experiences is important to set up a reasonable CMAWT in China. In this study, a classification theory for CMAWT is established to evaluate the CMAWT of China, Japan, America, and Australia. Results showed that China’s CMAWT is converting from the bureaucratic to the market type. Japan’s CMAWT is mainly the autonomous type. CMAWT of America and Australia are market type. Water transfer market in Australia is more sophisticated among the comparison countries. Government of China and Japan participated more in the agricultural water transfer than the government of America and Australia. Farmers participated least in agricultural water transfer in China than in other compared countries. The case study showed that the proposed theory can classify the CMAWT of different countries. [ABSTRACT FROM AUTHOR]

This study first analysed the crucial function of agricultural activities on groundwater system in Shijiazhuang Plain. Then the influence indexes of agricultural activities on regional groundwater are discussed. The Projection pursuit evaluation model and MapGIS technique have been used to evaluate the degree of such effect and its spatial difference. Finally, according to effect degree of agricultural activities on groundwater, Shijiazhuang Plain is divided into four types of regions. [ABSTRACT FROM AUTHOR]