星星草的生长对盐碱土壤氮素营养的影响

Effect of Puccinellia tenuiflora growth on nitrogen nutrition in alkalized soil

星星草生长不同年数碱化土壤与碱斑土壤比较，全氮含量、碱解氮含量、氨化强度、固氮强度、脲酶活性、蛋白酶活性、亚硝酸还原酶活性和硝酸还原酶活性均增加，星星草生长不同年数碱化土壤间存在不同差异。星星草生长不同年数土壤全氮含量与碱斑裸地差异显著；生长2年和3年与碱斑裸地土壤碱解氮含量差异显著；碱斑裸地与星星草生长3，4和5年土壤氨化强度、固氮强度、脲酶活性、蛋白酶活性和硝酸还原酶酶活性差异显著；说明星星草的生长对碱化土壤氮素营养状况具有一定的改良作用，综合来看星星草生长3～5年对碱化土壤的改良作用最佳。

The total nitrogen content, alkali-soluble nitrogen content, ammonification intensity, nitrogen fixation intensity, creased in alka urease activity, protinase activity, nitrite reductase activity and nitrate reductase activity inlized soil in which Puccinellia tenuiflora was grown （Pt soil） compared with alkali spot soil and the differences depended on the number of years for which it was grown. The total nitrogen content of the Pt soil for different years was significantly different from that of the alkali spot soil, and the alkali-soluble nitrogen content when P. tenuiflora was grown for three or four years was significantly different from the alkali spot soil, while the ammonification intensity, nitrogen fixation intensity, urease, proteinase, nitrite reductase and nitrate reductase activity alkali spot soil. All of the ab of the three, four or five year Pt soils were significantly different from that of the ove indicated that the growth of P. tenuiflora improved the nitrogen nutrition status of alkalized soil with the best effect when grown for 3-5 years.