摘要
为阐明玉米多品种间作对土壤团聚体组成和稳定性的影响,通过为期2 a的田间试验,测定并分析了单品种单播(T1)、两品种间作(T2)、三品种间作(T3)和四品种间作(T4)下根质量密度(RMD)、根长密度(RLD)与土壤团聚体粒级和稳定性指标[大于0.25 mm粒径团聚体含量(R＞0.25)、平均质量直径(MWD)、几何平均直径(GMD)]的变化规律.结果显示,与单品种单播相比,间作处理(T2～T4)的RMD、RLD、MWD、GMD、R＞0.25均呈递增趋势.与T1相比,T2、T3、T4处理的RMD分别显著(P＜0.05)提高232％、657％、702％,RLD分别显著提高515％、1 508％、1 531％;干筛法测定的R＞0.25分别显著提高0.65、0.89、1.02百分点,MWD分别显著提高7.2％、10.7％、15.7％,GMD分别显著提高13.1％、21.1％、31.9％;湿筛法测定的R＞0.25分别显著提高4.34、9.42、11.81百分点,MWD分别显著提高19.6％、41.2％、54.9％,GMD分别显著提高27.0％、64.9％、87.8％.综上,玉米多品种间作可通过提高根质量密度和根长密度等根系特征,改善土壤团聚体的粒径分布及其稳定性.
Abstract
In order to elucidate the effects of intercropping of maize varieties on soil aggregate composition and stabil-ity,a two-year field experiment was conducted.The root mass density(RMD),root length density(RLD),and soil aggregate indexs[＞0.25 mm aggregates content(R＞0.25),mean weight diameter(MWD),geometric mean diame-ter(GMD)]under different treatments[T1,one cultivar monoculture;T2,two-cultivar intercropping;T3,three-cultivar intercropping;T4,four-cultivar intercropping]were determined.It was shown that compared to monocul-ture,intercropping of maize varieties increased RMD,RLD,MWD,GMD and R＞0.25.Compared with the T1 treat-ment,the RMD under T2,T3,T4 treatments was significantly(P＜0.05)increased by 232％,657％,702％,re-spectively;the RLD was significantly increased by 515％,1 508％,1 531％,respectively;the R＞0.25 determined by dry sieving method was significantly increased by 0.65,0.89,1.02 percentage points;the MWD determined by dry sieving method was significantly increased by 7.2％,10.7％,15.7％,respectively;the GMD determined by dry sieving method was significantly increased by 13.1％,21.1％,31.9％,respectively;the R＞0.25 determined by wet sieving method was significantly increased by 4.34,9.42,11.81 percentage points;the MWD determined by wet sieving method was significantly increased by 19.6％,41.2％,54.9％,respectively;the GMD determined by wet sieving method was significantly increased by 27.0％,64.9％,87.8％,respectively.In conclusion,intercrop-ping of maize varieties could enhance the particle size distribution of soil aggregates and their stability by increasing root characteristics,such as root mass density and root length density.
国家科技期刊平台
NSTL
万方数据