淮河及其支流沿岸土壤硝态氮空间分布研究

Study on the Distribution of Soil Nitrate Along Huaihe River and Its Branches

采用GPS定位和土钻取样相结合的方法,研究了河南境内淮河干流及其四条支流(贾鲁河、惠济河、双洎河、清巽河)沿岸2km范围内土壤硝态氮的空间分布规律与累积状况,结果表明:该区域内土壤硝态氮含量普遍偏低,从空间分布来看,土壤硝态氮含量自上而下基本呈逐渐降低的趋势,一些样点存在硝态氮淋溶现象。0～80cm土层硝态氮累积总量清巽河沿岸土壤最高,32个取样点平均为98.8kghm-2;淮河干流沿岸土壤次之,32个点平均为78.9kghm-2;相比之下,双洎河、惠济河沿岸土壤硝态氮累积量较低,双洎河沿岸土壤40个点平均为73.5kghm-2,惠济河沿岸土壤64个点平均为72.3kghm-2;贾鲁河沿岸土壤最低,72个点平均仅为63.7kghm-2。同一河流不同取样点之间相差极大,可达几十倍至几百倍。

By means of GPS and soil core sampling, it was studied in this paper that the distribution and accumulation of soil nitrate in 2 km scope along Huaihe River and its four branches： Jialu River, Huiji River, Shuangji River, Qingxun River in Henan Province. The results indicated that the content of soil nitrate in this area was generally low. Nitrate content reduced generally with the soil depth. Some sampling plots existed the phenomenon of nitrate leaching. Nitrate accumulation in 0-80cm soil depth in 32 sampling plots along Qingxun River was highest, averaged as 98.8kg hm^-2, and in 32 sampling plots along Huaihe River was 78.9kg hm^-2, in 40 sampling plots along Shuangji River and 64 sampling plots along Huiji River was 73.5 and 72.3kg hm^-2 respectively, the lowest ones existed in the soil along Jialu River, only 63.7kg hm^-2 averaged by 72 sampling plots. Even for the same river, nitrate accumulation among sampling plots existed great difference.