近地遥感技术在大田作物株高测量中的研究现状与展望

Research Status and Prospect on Height Estimation of Field Crop Using Near-Field Remote Sensing Technology

株高是动态衡量作物健康和整体生长状况的关键指标,广泛用于估测作物的生物学产量和最终籽粒产量。传统的人工测量方式存在规模小、效率低以及耗时长等问题。近十年来,近地遥感技术在农业领域发展迅速,使得高精度、高频次、高效率的作物株高采集成为可能。本文首先回顾了国内外基于遥感手段获取株高研究的论文发表情况;其次对获取株高的不同平台以及传感器的基本原理、优势及其局限性进行了介绍和评述,重点论述了激光雷达和可见光相机两种传感器的测高流程与涉及的关键技术;在此基础上归纳了株高在作物生物量估算、倒伏监测、产量预测和辅助育种等方面的应用研究进展;最后对近地遥感技术在株高获取上存在的问题进行讨论分析,并从测高平台和传感器、裸土探测和插值算法、株高应用研究及农学与遥感测高差异四个方向进行了展望,可为今后近地遥感测高的研究与方法应用提供参考。

Plant height is a key indicator to dynamically measure crop health and overall growth status,which is widely used to estimate the biological yield and final grain yield of crops.The traditional manual measurement method is subjective,inefficient,and time-consuming.And the plant height obtained by sampling cannot evaluate the height of the whole field.In the last decade,remote sensing technology has developed rapidly in agriculture,which makes it possible to collect crop height information with high accuracy,high frequency,and high efficiency.This paper firstly reviewed the literature on obtaining plant height by using remote sensing technology for understanding the research progress of height estimation in the field.Unmanned aerial vehicle(UAV)platform with visible-light camera and light detection and ranging(LiDAR)were the most frequently used methods.And main research crops included wheat,corn,rice,and other staple food crops.Moreover,crop height measurement was mainly based on near-field remote sensing platforms such as ground,UAV,and airborne.Secondly,the basic principles,advantages,and limitations of different platforms and sensors for obtaining plant height were analyzed.The altimetry process and the key techniques of LiDAR and visible-light camera were discussed emphatically,which included extraction of crop canopy and soil elevation information,and feature matching of the imaging method.Then,the applications using plant height data,including the inversion of biomass,lodging identification,yield prediction,and breeding of crops were summarized.However,the commonly used empirical model has some problems such large measured data,unclear physical significance,and poor universality.Finally,the problems and challenges of near-field remote sensing technology in plant height acquisition were proposed.Selecting appropriate data to meet the needs of cost and accuracy,improving the measurement accuracy,and matching the plant height estimation of remote sensing with the agricultural application need to be considered.In addition,we prospected the future development was prospected from four aspects of 1)platform and sensor,2)bare soil detection and interpolation algorithm,3)plant height application research,and 4)the measurement difference of plant height between agronomy and remote sensing,which can provide references for future research and method application of near-field remote sensing height measurement.