基于微根管观测的盐渍农田向日葵根系三维结构模拟  

Three-dimensional Structure Simulation of Sunflower Root System in Saline Farmland Based on Minirhizotron Observation

作　　者：言巍鹏 何良伟 雷国庆 曾文治[1,2] YAN Wei-peng;HE Liang-wei;LEI Guo-qing;ZENG Wen-zhi(School of Water Resources and Hydropower Engineering,Wuhan University,Wuhan 430072,Hubei Province,China;State Key Laboratory of Water Resources and Hydropower Engineering Science,Wuhan University,Wuhan 430072,Hubei Province,China)

机构地区：[1]武汉大学水利水电学院,湖北武汉430072 [2]武汉大学水资源与水电工程科学国家重点实验室,湖北武汉430072

出　　处：《中国农村水利水电》2023年第12期248-257,共10页China Rural Water and Hydropower

基　　金：黑龙江省重点研发项目(2022ZX01A26);国家自然科学基金项目(52209066)。

摘　　要：根系作为作物汲取水分、养分的重要器官,其形态结构量化对于田间水肥管理具有重要意义。然而相比于地上部分,当前关于根系形态结构的研究十分有限,特别是在盐渍土壤。以内蒙古河套灌区开展的盐渍农田向日葵田间实验为背景,利用微根管法对不同盐分田块(低盐S1,高盐S2)的向日葵根长密度(RLD)动态变化进行了观测,并结合RootBox根系结构模型(RSA)对各田块作物根系三维结构进行模拟。结果显示,RootBox模型能够较好地模拟不同盐分下大田向日葵的根系形态,其微根管观测点的RLD模拟值与实测值接近,R2超过0.73,RRMSE小于0.28,但S2田块RLD模拟精度相对较低,RMSE比S1田块的高0.31 cm/cm^(3)。并且,S1田块平均RLD模拟分布与微根管RLD观测值分布接近,而在S2田块,二者差异较为显著,特别是在60~90 cm土层。上述结果表明,微根管观测法和根系结构模型可为盐渍农田作物根系形态结构量化提供工具支持,并且高盐田块作物根系量化效果受土壤盐分影响更为显著。As an important organ for crops to absorb water and nutrients,the quantification of root system is of great significance for water and fertilizer management in the field.However,compared with aboveground parts,the current studies on root system architecture are very limited,especially in saline soils.In this paper,the dynamic changes of sunflower root length density(RLD)in different salt fields(low sa⁃line S1,high saline S2)were observed by using minirhizotron based on the experimental data of saline farmland sunflower in Hetao Irrigation District of Inner Mongolia,and the three-dimensional structure of crop roots in each field was simulated by combining root system architec⁃ture model(RSA)RootBox.The results showed that RootBox could well simulate the root system of sunflower under different salinity.The simulated RLD values of minirhizotron observation site were close to the measured values,R2 was more than 0.73 and RRMSE was less than 0.28.However,the RLD simulation accuracy of S2 field was relatively lower,and RMSE was 0.84 higher than that of S1 field.Moreover,the simulated average RLD distribution in S1 field was close to the observed minirhizotron RLD distribution,while the difference was significant in S2 field,especially in the 60-90 cm soil layer.These results indicated that the minirhizotron method and root system architecture model could provide support for quantifying the morphological structure of crop roots in saline fields,and the quantitative effect of crop roots in high saline fields was more significantly affected by soil salinity.

关 键 词：盐渍农田 向日葵 根系 微根管 根系结构模型 

分 类 号：TV93[水利工程—水利水电工程]