基于精确大田数据的玉米根系三维结构动态模型校验及植株土壤氮磷吸收时空特征的定量化

项目名称： 基于精确大田数据的玉米根系三维结构动态模型校验及植株土壤氮磷吸收时空特征的定量化

项目编号： No.41471235

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 地质学

项目作者： 郭焱

作者单位： 中国农业大学

项目金额： 82万元

中文摘要： 粗放的农田养分管理导致我国化肥养分利用率低，同时还带来了农业面源污染等问题。采用基于模型的土壤-作物系统的集成管理方法，可显著地降低化肥施用量，但此方法对根系-土壤互作的考虑较粗略。植物根系结构与土壤养分分布在时空上的协调性对养分利用率起着关键作用。已有的根系三维结构模型因缺乏大田数据校验，使得模型模拟结果难以准确地反映大田作物根系的特征，基于这些模型模拟根系养分吸收的可靠性有限。本项目拟采用申请人团队已建立的玉米根系主根三维结构的田间原位测定方法、田间根系取样集成系统以及侧根结构分析方法，对不同品种、不同生育期的玉米植株根系结构进行测定，构建精确反映大田玉米根系三维结构动态的模型并进行系统校验。将此模型与国际上广泛采用的土壤水分、养分运移模型耦合，构建基于根系生长动态的土壤氮磷吸收模型，并由此构建大田氮磷养分的优化管理系统，为提高农田养分利用率、减少农业污染提供定量化的工具。

中文关键词： 土壤-植物相互作用；养分过程模拟；精准农业；氮素营养；根系结构模型

英文摘要： Improper use of nutrient resources leads to low nutrient use efficiency in China, and results in environmental problems including nonpoint source pollution. The input of nitrogen fertilizer can be significantly reduced using the model-driven integrated soil-crop system management approach, but root system-soil interaction is only simply considered in this approach. The coordination of the spatial-temporal distribution of root system and soil nutrients is a key factor in determing soil nutrient use efficiency.Because of lacking root architecture data collected in the field, the constructed three-dimensional (3D) root architecture models have not been well calibrated and validated, so the reliability of their simulation results are limited.We plan to conduct a field experiment using different maize cultivars in this project, and quantify the root system architecture of individual maize plants at different growth stages. We plan to adopt 3D digitizing method to collect the spatial coordinates of maize nodal roots in situ in the field, and use an integrated method to sample maize root systems of individual plants and quantify the archtecture of lateral roots.The collected data will be used to calibrate and validate a 3D dynamic model of maize root architecture.This root model will be combined with a 3D soil water and solute transport model to simulate nitrogen and phosphorus uptake of maize plants.A system for optimizing field nitrogen and phosphous nutrient management will be developed based on the combined 3D models.The study can provide useful tools for improving nutrient use efficiency and reducing environmental pollution derived from fertilizer application.

英文关键词： Soil-plant interaction;Nutrient uptake modeling;Precision agriculture;Nitrogen nutrient;Root architecture model