质地和根系深度对水分探头埋设的仿真模拟  

Simulated effects of texture and rooting depth on soil moisture sensor placement

作　　者：樊军[1,2] 王全九[2] 汪羽宁[1] 

机构地区：[1]西北农林科技大学黄土高原土壤侵蚀与旱地农业国家重点实验室,陕西杨凌712100 [2]中国科学院水利部水土保持研究所,陕西杨凌712100

出　　处：《排灌机械工程学报》2013年第1期70-74,共5页Journal of Drainage and Irrigation Machinery Engineering

基　　金："十二五"国家科技支撑计划项目(2011BAD29B05);国家自然科学基金资助项目(91025018;41271239)

摘　　要：利用Hydrus-1D模型模拟不同植物根系深度和不同土壤质地条件下的土壤水分动态与平衡,研究了根系分布深度和质地对控制灌溉土壤水分探头埋设深度的影响,并利用试验进行了验证.土壤质地和植物根系分布深度对探头埋设深度有显著影响,砂壤土和壤土分别采用高频低灌量和低频率高灌量的方法.浅根系植物(10 cm)在砂壤土条件下探头埋设5 cm深度最佳,但是根系深度增大到30 cm,探头应该埋设到20 cm深度.对壤土而言,利用位于根系1/2至1/3处的探头控制灌溉.太浅的埋设深度会导致灌溉频率增大,太深的埋设可能造成植物缺水.黏土条件下,结果较为复杂,探头的埋设深度需要田间试验研究.研究结果表明:针对具体植物,因其需水规律和生理特征的不同,根据植物需水规律来调整探头的控制范围达到高效节水目的.Soil water dynamics and balance under various rooting depth and soil texture were simulated by the Hydrus - 1D model to investigate the effects of soil texture and rooting depth on sensor depth in soil profile, and the simulated results were validated by experimental efforts. It is concluded that the soil texture and distribution of plant root has significant influence on the sensor depth. Soil moisture sensor should be buried at 5 cm under sand soil for plants with shallow roots （ 10 cm） , while those should be buried at 20 cm depth for rooting depth of 30 cm. As for loam soil, sensor placement locates in the one third to two third rooting depth is best. Shallow sensor placement could increase irrigation frequency and deep sensor placement could results in plant water stress. The complex results were achieved under fine soft and plants with deep roots, therefore, field observation should be done for the buried depth of sensor in soil profile. In conclusion, it is useful to guide sensor placement by simula- tion for sand and loam soil, but it is not suitable for clay soil, Optimum sensor placement should be adjusted according to plant water requirement which affected by plant species. More detailed resear- ches should be focused on the situations that sensor buried depth affected by non-uniform irrigation and temporal and spatial variations of plant roots.

关 键 词：土壤水分 土壤质地 灌溉 计算机模拟 入渗 

分 类 号：S277.9[农业科学—农业水土工程] S152.7[农业科学—农业工程]