Effect of Shelterbelts Underground Roots Management on Soil Water Distribution in Agriculture Ecosystems
Shelterbelt, a common man made component in agriculture ecosystems, has a great contribution on improving cropland microclimate and blocking off harmful wind. However, with respect to agriculture ecosystems, the issue of farmland shelterbelts negative effect on crop yield is disputed all the time. Among the approaches of alleviating this bad effect; root pruning is an effective way in practice. In the present study, 0.6 m deep root barrier was applied to agriculture ecosystems with different distance (3.0, 2.5, 2.0,1.5 and 1.0 m) from trees in net of farmland shelterbelt to manage tree-crop underground roots competition. With the aim to evaluate the soil water distribution changing at root barrier zone and within four direction of shelterbelts at different distance from tree row, volumetric soil water content (VSWC) was investigated on the top 0-20 cm of soil, at wheat heading and grain filling periods, 5, 10, 15 days after saturated irrigation. It was found that soil water content within four directions of the shelterbelt responded differently both to the root pruning and nonpruning. Compared to the two period of investigation, VSWC changed similarly after irrigation of 5, 10 and 15 days. At 5 days after irrigation, VSWC near shelterbelts at the north side of the plot was the lowest among the four sides, followed by west and east side of the plot near the shelterbelts, south side was the highest of the plot; at 10 days after irrigation, all the VSWC decreased near the shelterbelts within 0.1 H; and at 15 days after irrigation all the VSWC decreased sharply within 0.3 H, the highest VSWC at the south side of the plot within O.3-0.5H near the shelterbelts for the reason of shading by trees. Installation of polyethylene sheeting root barriers increased the soil water content near the tree row. However, this treatment decreased soil water content within the tree row as compared to the no barrier treatment after long time did not get water. The results suggested that the soil water content of four direction of tree row in one plot varied differently. The soil water distribution was influenced greatly by tree row of east-west orientation of shelterbelt, but there was no significant difference between barrier and no barrier zones. In addition, near north-south orientation of tree row soil water distribution was not greatly affected by root barrier, but root barrier took effect on north to south direction of tree row. Judged from the relative effect of 3.0, 2.5, 2.0, 1.5 and 1.0 m root barriers from tree row, the roots management of 1 m root barrier from tree row was better in practice. This research provides a useful method for farmers to manage shelterbelts roots in agriculture ecosystems.
Agroforestry ecosystems Soil water distribution Root barrier
Zuozhou Chen Yuqing Zhang Bin Wu Zhipei Li Na Lei
Beijing Forestry University, School of Water and Soil Conservation BJFU, SWSC Beijing, China
国际会议
昆明
英文
298-303
2010-10-17（万方平台首次上网日期，不代表论文的发表时间）