Studying the spatial distribution characteristics of groundwater quality in the coastal plain and its relationship with land use and seawater intrusion is of great significance for maintaining the stability of the coastal groundwater environment, rationally using land and preventing seawater intrusion in international community. Taking Longkou, Shandong Province as an example, through field surveys and sampling monitoring, and using methods, such as semi-variogram and Kriging interpolation, the spatial distribution characteristics of groundwater quality in the study area and the coupling relationship with land use and seawater intrusion were analyzed. The results show that the main chemical types of groundwater in Longkou are the HCO₃·Cl–Na·Ca·Mg and HCO₃·Cl–Na·Ca types. Spatial distribution characteristics of groundwater quality are closely related to land use and seawater intrusion, and the mass concentration of most ions gradually decreases from the coast to the inland. The spatial variability of Cl⁻ and Na⁺ is greatly affected by seawater intrusion. The spatial distribution of NO₃⁻ is closely related to the distribution of agricultural land and residential land. We should constantly monitor the scope of seawater intrusion and the total amount of sewage discharged from agriculture and domestic life to effectively prevent the further deterioration of coastal groundwater quality.

研究滨海平原地下水水质空间分布特征及其与土地利用、海水入侵的关系，对于国际社会维护滨海地下水环境稳定、合理利用土地、防止海水入侵具有重要意义。以山东省龙口市为例，通过实地调查和抽样监测，利用半变异函数、克里金插值等方法，研究区地下水水质空间分布特征及与土地利用和海水入侵的耦合关系进行了分析。结果表明，龙口地下水的主要化学类型为HCO ₃ ·Cl-Na·Ca·Mg和HCO ₃·Cl-Na·Ca 类型。地下水水质空间分布特征与土地利用和海水入侵密切相关，大部分离子的质量浓度从沿海向内陆逐渐降低。Cl ^-和Na ⁺的空间变异性受海水入侵的影响很大。NO ₃ ⁻的空间分布与农用地和居住用地的分布密切相关。要不断监测海水入侵范围和农业生活污水排放总量，有效防止近岸地下水水质进一步恶化。