CUI Jian DUJizhong LI Xiao LI Xuguang ZHU Wei MA Hongwei YUE Mingxin

（Shenyang Institute of Geology Mineral Resources, Shenyang 110034, China）

Abstract:

Since 2002, study onrelationship between the change of land use and groundwater quality has been carried out in China, but it has obvious limitations. The one is that the research area limited in karst or oasis area, the other is that the study is confined to basin or larger regional scale. However, study on land use / cover change in small scale has been specific concerned, at the same time, effects of land use change on groundwater quality in towns where land use changes fast, or ecological environment is relatively fragile are rarely researched. Effects of land use and land cover changes on groundwater quality in Qiqihar City, China were analyzedwith the method of LUCC based on three temporal remote sensing images of the year 1995, 2003, and 2011.The dynamic trend and degree of land use in the district was also analyzed. At the same time, a regression equation was used to analyze time trend of groundwater quality by EXCEL soft. Results show that the main landuse types were dry land, wetland and construction land in the study area. And the area of dry land was the largest, accounting for higher than 45% of the whole study area. During the recent two decades, the areas of wetland have decreased continuously(112.38 km2) and transformed into dry land, paddy land and construction land. The overall degree of land use changes has been retarded since 2003. There was a dynamic relationship between the groundwater quality and the change of land use. Trend of NO3--N concentration in groundwater was closely related to the transformation between construction land and dry land. Nitrogen pollution of groundwater in the study area was mainly affected by urban and rural residents living and industrial production, instead of chemical fertilizers in agricultural production. Area whereSO42-, Cl- and total hardness concentrations rose with the fastest speed had been used as construction land, on the contrary, area where SO42-, Cl- and total hardness concentrations decreased with the fastest speed areconstruction land convertedinto other types of land. The rapid development of urbanization and industrial long-term land resources, has become the main land use which has a direct impact on groundwater quality in the area.

Therefore, based on the administrative region served as research unit, the research of land use change and its effects tohydrogeologic environment are very important for the protection of the resources and environment of Qiqihar City.

Key words: land use change; groundwater; water quality; Qiqihar City

EARTH AND ENVIRONMENT Vol. 43, No.3, Tot No.305, 2015, Page 308-315