西北旱作农田不同耕作模式对土壤性状及小麦产量的影响  

Effects of different tillage practices on soil properties and wheat yields in dry farmland of northwest China

作　　者：侯贤清[1] 李荣[1] 贾志宽[2] 韩清芳[2] 

机构地区：[1]宁夏大学农学院,银川750021 [2]西北农林科技大学中国旱区节水农业研究院/农业部西北黄土高原作物生理生态与耕作重点实验室,陕西杨凌712100

出　　处：《植物营养与肥料学报》2017年第5期1146-1157,共12页Journal of Plant Nutrition and Fertilizers

基　　金：国家自然科学基金(31301280);国家"十一五"科技支撑课题(2006BAD29B03)资助

摘　　要：【目的】在雨养农业区,旱作区因连年翻耕而引起严重的土壤质量退化,使作物生产力下降,需定期改变其耕作方式。免耕深松隔年轮耕可以降低土壤容重,增加耕层土壤团聚体和有机碳氮的含量,增强土壤蓄水保墒能力,对改善土壤性状和提高作物产量具有重要意义。【方法】本研究于2007~2010年在宁夏南部半旱区进行了两年免耕一年深松(NT/ST/NT)、两年深松一年免耕(ST/NT/ST)、连年翻耕(CT)3种耕作模式试验,研究了其对耕层土壤容重、团聚体、土壤有机碳氮含量、土壤水分及作物产量的影响。【结果】3年耕作处理后,与连年翻耕相比,NT/ST/NT、ST/NT/ST处理0—20 cm层土壤容重分别降低了4.4%和7.3%,20—40 cm土层分别降低2.1%和5.7%,40—60 cm土层分别降低4.1%和5.5%;土壤孔隙度0—20 cm土层分别提高了4.1%和6.8%,20—40 cm土层提高了2.1%和4.3%,40—60 cm土层提高了5.5%和5.7%。0—20 cm土层,NT/ST/NT处理0.25~2 mm机械稳定性团聚体含量平均较CT处理提高了12.4%,ST/NT/ST处理>2 mm机械稳定性团聚体含量较CT处理平均提高了42.0%;20—40 cm土层,NT/ST/NT、ST/NT/ST处理>2 mm团聚体含量较CT处理平均分别提高了44.3%和50.4%。两种轮耕模式使0—40 cm土层土壤团聚体平均重量直径分别显著高于CT处理21.8%和22.5%,几何平均直径分别高于CT处理9.6%和9.5%。三个处理耕层土壤有机碳氮含量均比试验前有不同程度的增加,轮耕处理0—30 cm土层0.25~2 mm粒级有机碳含量和<0.25 mm粒级全氮含量显著高于CT,以ST/NT/ST处理效果最佳。NT/ST/NT和ST/NT/ST处理0—10 cm土层0.25~2 mm团聚体有机碳含量较CT处理分别显著提高7.9%和10.2%,10—20 cm土层分别提高19.0%和15.7%,20—30 cm土层分别提高10.6%和13.3%;0—10 cm土层<0.25 mm粒级全氮含量显著提高9.4%和10.9%,10—20 cm土层分别提高6.8%和10.2%,20—30 cm土层分别提高7.4%和9.3%。研究期间,NT/ST/NT和ST/NT/ST处理较CT处�[ Objectives ] In rain-fed semi-arid agro-ecosystems in northwest China, continuous ploughing has led to serious soil deterioration and crop productivity decline. Adopting suitable tillage practices is very important for improving soil fertility and keeping stable crop yields. [ Methods ] A field experiment was conducted in arid area of southern Ningxia from 2007 to 2010. The treated tillage patterns included： 1） no-tillage in the first year（CT）, subsoiling in the second year and no-tillage in the third year （NT/ST/NT）; 2） subsoiling in the first year, no-tillage in the second year and subsoiling in the third year （ST/NT/ST）; 3） ploughing before and after harvest every year. The soil bulk density, aggregate, soil organic carbon （SOC）, total nitrogen （TN） content, soil water, and crop yields were determined. [ Results ] After 3 years＇ treatments, the soil bulk density under NT/ST/NT and ST/NT/ST was significantly decreased by 4.4% and 7.3% at the 0-20 cm depth, 2.1% and 5.7% at the 20-40 cm depth and 4.1% and 5.5% at the 40-60 cm depth, compared with CT. The total soil porosity under NT/ST/NT and ST/NT/ST was 4.1% and 6.8% higher than that under CT at the 0-20 cm depth, 2.1% and 4.3% at the 20-40 cm depth and 5.5% and 5.7% at the 40-60 cm depth, respectively. At 0-20 cm, the mean amount of the 0.25-2 mm elastic-stable aggregate in NT/ST/NT was 12.4% higher than in CT, and the mean amount of the 〉 2 mm elastic-stable aggregate in ST/NT/ST was 42.0% higher than in CT. At 20-40 cm, the mean amounts of the 〉 2 mm elastic-stable aggregate under NT/ST/NT and ST/NT/ST were 44.3% and 50.4% higher than CT, respectively. The mean weight diameter values in NT/ST/NT and ST/NT/ST were 21.8% and 22.5% higher than in CT respectively, and the geometric mean diameter values were 9.6% and 9.5% higher than CT at 0-40 cm depth. The soil organic carbon （SOC） and total nitrogen （TN） contents at 0-40 cm depth were increased in all treatments compared with the initial background value. Significan

关 键 词：旱作农田 土壤耕作 团聚体 有机碳 土壤水分 小麦产量 

分 类 号：S512.1[农业科学—作物学]