土壤改良剂对黔西北两种植烟土壤氮矿化的影响  

Effects of soil amendment on nitrogen mineralization of soils at two altitudes in northwest Guizhou

作　　者：潘金华[1,2] 庄舜尧[2] 黄化刚 陈雪 史学正[2] 曹志洪[2] 

机构地区：[1]贵州省烟草公司毕节市公司,贵州省毕节市天河路116号551700 [2]中国科学院南京土壤研究所土壤与农业可持续发展国家重点实验室,南京市玄武区北京东路71号210008

出　　处：《烟草科技》2017年第5期10-18,共9页Tobacco Science & Technology

基　　金：贵州省烟草公司毕节市公司科技专项项目"土壤深耕对毕节烤烟产质量提升及机理研究"(毕节合2015-01);上海烟草集团有限责任公司科技专项项目"烟草优质高效生态安全的土肥一生管理技术之研究与示范"(CF56.1-ZJ5)

摘　　要：为揭示土壤改良剂对两种植烟土壤氮素矿化特征的影响机理,以贵州毕节地区黄壤(Q,海拔1 320 m)和棕壤(W,海拔2 120 m)为试验对象,通过模拟田间试验分析了土壤改良剂(T20)对两种土壤氮矿化及硝化作用的影响。采用室内恒温间歇淋洗好气培养法(Stanford法),设置对照和3种T20添加比例(1%、2%、5%)处理。结果表明:Q1(Q+1%T20)、Q2(Q+2%T20)和Q3(Q+5%T20)处理的累积净氮矿化量分别较对照提高21.35%、37.66%和26.06%;而W1(W+1%T20)与W2(W+2%T20)处理的累积净氮矿化量分别较对照提高10.83%和5.71%,W3(W+5%T20)处理的累积净氮矿化量较对照降低4.50%,累积净氮矿化量随T20添加量的增加而减少。利用一级动力学方程N_t=N_(t0)(1-e^(-kt))拟合发现,累积净氮矿化量与培养时间有很好的相关性,拟合后的方程决定系数R^2为0.956 3~0.985 9,均达极显著水平;黄壤土矿化势N10平均69.45 mg·kg^(-1),T20各添加处理的土壤矿化率k均高于对照,且随添加量的增加而增加,累积净氮矿化量N_t、N_(15)/N_t、N_0/TN及矿化综合指数(N_0×k)均随T20添加量增加表现出先增加后降低的趋势;棕壤土矿化势N_0、N_t、N_(15)/N_t、N_0/TN及矿化综合指数(N_0×k)均随添加量增加而降低。运用方程N_(tNO3)=N_(t0)/(1+e^(a-bt))拟合发现,两种土壤硝态氮累积量与培养时间的拟合方程决定系数R^2为0.983 2~0.999 9,均达到极显著水平,其V_(max)和T_(max)均随添加量增加而先增加后减少。随添加量的增加Q硝化促进率由-8.34%上升至7.90%,Q矿化促进率先增加后降低;W硝化促进率先升高后降低,矿化促进率由10.80%下降至-4.49%。因此,在黔西北植烟土壤上施用2%的土壤改良剂可以促进土壤有机氮的矿化以及硝化作用,达到增强黔西北两种海拔土壤氮素有效利用及改善土壤肥力的综合目标。To evaluate the effects of soil amendment on nitrogen mineralization characteristics of soils at different altitudes, a simulated field experiment was conducted to study the effects of soil amendment on nitrogen mineralization and nitrification in soils, yellow soils （Q） at the altitude of 1 320 m and brown soils （W） at the altitude of 2 120 m from Bijie in Guizhou. Stanford method （aerobic culture method under indoor constant temperature and intermittent leaching） was adopted, and the control and three treatments with different T20 addition rates （1%, 2% and 5%） were set up. The results showed that comparing with the control, the accumulated mineralized N of Q1（Q＋1%T20）, Q2（Q＋2%T20）, Q3 （Q＋5%T20）, W1（W＋1%T20） and W2（W＋2%T20） increased by 21.35%, 37.66%, 26.06%, 10.83% and 5.71%, respectively; however that of W3 （W＋5% T20） decreased by 4.50%. With the rise of T20 addition rate, the accumulated mineralized N decreased. The fitting results of quasi-one stage kinetic equation Nt=Nt0 （1-e^-kt）indicated that there was a good correlation between the amount of accumulated mineralized N and time. Determination coefficient R2 （0.956 3-0.985 9） from the fitted equation had significantly difference. Mineralization potential （N0） of yellow soil was 69.45 mg·kg^-1 on average. Soil mineralization rates （k） of the treatments with different addition rates were higher than the control, and soil mineralization rate increased with the rise of addition rate. Accumulated mineralized N （Nt, N15/Nt and N0/TN） and mineralization index （N0×k） of different treatments increased first then decreased, and mineralization potential （N0）, accumulated mineralized N （Nt, N15/Nt and N0/TN） and mineralization index （N0×k） of brown soil decreased with the increase of T20 addition rate. The fitting results of equation NtNO3=Nt0/（1＋e^a-bt） showed that the determination coefficient R^2 （0.983 2-0.999 9） from the fitted equation for nitrate N accumulatio

关 键 词：土壤改良剂 黄壤 棕壤 海拔 氮素 矿化 硝化作用 

分 类 号：S572.061[农业科学—烟草工业]