Root Distribution and N Acquisition in an Alfalfa and Corn Intercropping System
Root Distribution and N Acquisition in an Alfalfa and Corn Intercropping System
复制标题
DOI：
10.5539/jas.v5n9p128
复制
发表时间：
2013-08
期刊：
影响因子：
--
通讯作者：
Guiguo Zhang;Chongyu Zhang;Zaibin Yang;S. Dong
中科院分区：
文献类型：
--
作者：
Guiguo Zhang;Chongyu Zhang;Zaibin Yang;S. Dong
多年生豆科作物和一年生谷类作物根系分布的研究较少。研究了不同紫花苜蓿（Medicago sativa L.）和玉米（Zea mays L.）间作模式通过2007-2009年连续3年的田间试验，研究了苜蓿与玉米行交替种植的4种模式：玉米行以2：2、3：2、4：2和5：2的比例播种。玉米和苜蓿的单一作物被用作对照。在玉米灌浆盛期采用螺旋取样法连续3年采集不同土层的根系，用根长密度（RLD）描述间作苜蓿玉米根系的空间分布。结果表明，苜蓿/玉米间作系统的RLD值大于单种苜蓿或玉米。此外，间作苜蓿的根质量中心下降到更深的土壤层，林分年龄的增长，同样向相关的玉米行横向增殖。而玉米根团在土壤剖面较浅处扩展，且更多地向邻近的苜蓿根区横向分布。苜蓿与玉米行之间的差距是两种植物根系的最大定植区，且两种植物根系的混合度和RLD最大。苜蓿/玉米复合群落中各组分作物根系空间分布的互补性和相容性是苜蓿/玉米复合群落生物产量较高的根本原因。
Little attention has been paid to root distribution in combined perennial legume and annual cereal crops. The main objectives of this study were to explore the regularity of root distribution and the influence on nitrogen (N) acquisition in different alfalfa (Medicago sativa L.) and corn (Zea mays L.) intercropping patterns. A three year (2007–2009) field experiment studied four intercropping patterns of alternating alfalfa and corn rows with alfalfa:corn rows sown at 2:2, 3:2, 4:2, and 5:2. Sole crops of corn and alfalfa were used as controls. Roots were sampled over 3 consecutive years by auger sampling method in the prime filling stage of corn from different soil depth, and the root length density (RLD) was used to describe the root spatial distribution of intercropped alfalfa and corn. The results showed that the alfalfa/corn intercropping system had the greater RLD values compared to the sole cropped alfalfa or corn. In addition, the root mass centre of intercropped alfalfa descended into deeper soil layers with advancing stand age, and likewise proliferated laterally towards associated corn rows. Whereas the corn root mass spread at relative shallow soil profile, and also more deployed laterally to neighboring alfalfa root zone. The gap between alfalfa and corn rows was the highest colonized area with greater intermingling and the highest RLD of both species root. The complementary and compatibility of the root spatial distribution of component crops in alfalfa/corn community were the essential cause for better biomass yield.