焉耆盆地绿洲区水体硝态氮量调查及其空间分布研究  

Investigation into Nitrate Nitrogen Concentration and Spatial Distribution Study in Water of the Oasis Area of Yanqi Basin

作　　者：汪昌树 杨鹏年[1] 张瀚[1] 于宴民 

机构地区：[1]新疆农业大学水利与土木工程学院,乌鲁木齐830052

出　　处：《新疆农业科学》2016年第10期1877-1884,共8页Xinjiang Agricultural Sciences

基　　金：国家自然科学基金项目"人类活动影响下焉耆盆地水氮迁移特征及规律研究"(51369030);2015年度新疆农业大学研究生科研创新项目"变化环境下焉耆盆地绿洲区硝态氮时空特征"(XJAUGRI2015-009);新疆水文学及水资源重点学科基金(XJSWSZYZDXK20101202)~~

摘　　要：【目的】研究焉耆盆地绿洲区水体硝态氮污染现状及地下水空间分布规律。【方法】2014~2015年通过野外采样及室内化验,利用紫外可见分光光度法测定地表水（80个）、不同埋深地下水（284个）水体硝酸盐含量,并运用统计分析及克里金（Kriging）法研究盆地现状硝态氮量及空间分布。【结果】除包气带水体外,绿洲区水体硝态氮量水平总体较低,但不同类型、区域水体间差异性明显,变异性较高。主要河流与农田排渠均受到人为因素干扰,部分农田排渠硝态氮量已超过10.0 mg/L。地下水硝态氮量与埋深密切相关,包气带水〉手压井〉灌溉井〉自来水井,随着埋深的增加,硝态氮量呈减小的趋势。氮素进入田间后,富集于耕作层等包气带土层,为进入地下水的起点。普通克里金插值（Or-Kriging）结果显示,部分典型灌区地下水已接近甚至超过国际（WHO）地下水安全允许浓度（硝态氮量〉10.0 mg/L）,较高的区域多分布于典型灌区。【结论】集约化种植氮肥施用量的增加、利用率偏低是焉耆盆地绿洲区水体硝态氮量升高的主要原因,包气带中积累过多的氮素是水体污染的潜在风险。【Objective】To investigate and study the status of the nitrate nitrogen contamination and spatial distribution in groundwater of the oasis area of Yanqi Basin.【Method】Through field sampling and laboratory analysis,the nitrate nitrogen concentration of 80 samples for surface water and 284 samples from different depths of groundwater was sampled and tested with the method of ultraviolet-visible spectrophotometry absorption in the oasis area of Yanqi Basin,then the status of the nitrate nitrogen contamination and spatial distribution was studied.【Result】The averaged nitrate nitrogen concentration was at a low level except the water of the aeration zone,but the concentration between different types and region was obviously different and the variation was very high. The main rivers and farmland drainage channels were affected by human factors,and the amount of nitrate nitrogen in some farmland drainage ditch has exceeded 10. 0 mg/L. The nitrate nitrogen concentration of groundwater and depth were closely related. The order of average concentration was： aeration zone〉 hand-pumping wells〉 irrigation wells〉 tap water wells. With the increase of water depth,the corresponding nitrate nitrogen concentration decreased. After entering the field,the nitrogen is enriched in the soil layer of the aeration zone,which is the starting point of the groundwater. Or-Kriging interpolation results showed that the groundwater of some typical irrigation districts was close to or even exceeded the international groundwater allowable limit（ 10. 0 mg/L）,and most of the high concentration was relatively distributed in the typical irrigation area.【Conclusion】The increased amount of nitrogen fertilizer and low utilization applied in intensive cultivation is the fundamental cause of the increase of nitrate nitrogen concentration in water of oasis area of Yanqi Basin in recent years,from which conclusion can be drawn that the excessive nitrogen accumulation in the aeration zone is the potential risk of water pollution.

关 键 词：硝态氮 空间分布 氮肥 焉耆盆地 绿洲 

分 类 号：S275.6[农业科学—农业水土工程] S274.1[农业科学—农业工程]