佳木斯江北水源地准保区不同土地利用类型地下水土中氮磷的分布特征

Distribution Characteristics of Nitrogen and Phosphorus in Groundwater and Soil under Different Land Use Types in Quasi-protected Area of Jiangbei Water Source Area in Jiamusi

以黑龙江省佳木斯市江北水源地准保护区为研究区,选取7种典型土地利用类型,研究不同土地利用类型下地下水和包气带氮磷的分布特征.结果表明:在0~180cm包气带深度内水浇地中氨态氮(NH_(4)^(+))显著低于其他土地利用方式(p<0.05,下同);居民点包气带可溶性氮、磷分布特征与其他土地利用方式差异最大,其中硝态氮(NO_(3)^(-),0~150cm)、亚硝态氮(NO_(2)^(-),0~120cm)和溶解态磷(DP,0~90cm)的含量显著高于其他土地利用方式,且含量随土壤深度的增加而降低;所有土地利用类型的地下水中,NO_(3)^(-)是总氮(TN)主要组成成分,其中居民点和水浇地地下水中NO_(3)^(-)含量和TN显著高于其他土地利用方式,农业生产、粪便和废水是居民点位地下水中NO_(3)^(-)的主要来源.Pearson相关分析结果表明:研究区地下水NO_(2)^(-)含量与0~30cm深度土壤中的NH_(4)^(+),NO_(2)^(-)和NO_(3)^(-)含量以及电导率呈显著正相关;NH_(4)^(+)含量与150~180cm深度土壤的pH值呈显著正相关;TN与0~30cm深度土壤中的NH_(4)^(+)和NO_(2)^(-)含量呈显著正相关.研究结果为深入了解不同土地利用方式下包气带土壤氮、磷分布特征与浅层地下水水质的关系提供理论依据.

Taking the quasi-protected area of Jiangbei water source area in Jiamusi City,Heilongjiang Province as the research area,we selected seven typical land use types to study the distribution characteristics of nitrogen and phosphorus in groundwater and aeration zone under different land use types.The results show that the NH_(4)^(+) content in the irrigated land is significantly lower(p<0.05,same below)than that in other land use types within the depth range of 0—180 cm in the aeration zone.The distribution characteristics of dissolved nitrogen and phosphorus in residential area aeration zone are the most different from those in other land use types.The contents of NO_(3)^(-)(0—150 cm),NO_(2)^(-)(0—120 cm),and DP(0—90 cm)in the residential area aeration zone are significantly higher than those in other land use types,and their contents decrease with the increase of soil depth.For all land use types of groundwater,NO_(3)^(-) is the main component of TN,and the contents of NO_(3)^(-) and TN in the groundwater of residential areas and irrigated land are significantly higher than those in other land use types.Agricultural production,manure and wastewater are the main sources of NO_(3)^(-) in groundwater at residential areas.The results of Pearson correlation analysis show that the content of NO_(2)^(-) in groundwater is significantly positively correlated with the contents of NH_(4)^(+),NO_(2)^(-),NO_(3)^(-),and conductivity in the soil at 0—30 cm depth.There is a significant positive correlation between NH_(4)^(+) content and soil pH value at 150—180 cm depth.TN is significantly positively correlated with NH_(4)^(+) and NO_(2)^(-) contents in 0—30 cm soil.The research results provide a theoretical basis for an in-depth understanding of the relationship between the distribution characteristics of nitrogen and phosphorus in the aeration zone soil and the quality of shallow groundwater under different land use types.