土壤中元素遥感定量反演研究进展与展望

Quantitative remote sensing inversion of elements in soils:Advances in research and future prospects

【研究目的】土壤质量的优劣与人类生活密切相关。鉴于传统的土壤调查方法无法满足大面积土壤质量的动态监测需求,如何发挥高光谱遥感技术宏观、实时、原位、快速等优势进行土壤元素定量反演已成为遥感应用领域的热点和难点。【研究方法】文章围绕土壤元素的直接定量反演、利用土壤中元素相关性的间接定量反演以及基于植物光谱的土壤元素定量反演三种遥感定量反演方法,系统总结了其主要原理、优势与研究现状,从学科交叉融合角度展望了相关领域未来发展方向。【研究结果】当前常用的土壤元素定量反演方法均难于大范围推广应用。相比而言,利用植物叶片或冠层的光谱间接反演土壤元素含量的方法可信度更高。利用生态地球化学领域的研究成果,有助于找到目标元素在不同植物中特有的光谱学效应信息,解码基于植物光谱的土壤元素定量反演原理。【结论】推进学科交叉融合,深化基于大数据挖掘和土壤理化性质的研究,是突破土壤元素广域监测技术瓶颈的有利发展方向。

This paper is the result of agricultural geological survey engineering.[Objective]Soil quality is closely related to human activities.Given that traditional methods fall short in achieving the large−scale dynamic monitoring of soil quality,the quantitative inversion of elements in soils using hyperspectral remote sensing,which proves macroscopic,real−time,in−situ,and fast,has emerged as a hot topic and challenge in the field of remote sensing application.[Methods]This paper explores three methods for quantitative remote sensing inversion of elements in soils:direct quantitative inversion,indirect quantitative inversion using correlations among the elements,and quantitative inversion based on plant spectra.Specifically,this paper systematically summarizes the primary principles,advantages,and current research status of these methods and proposes future trends in relevant fields from the perspective of interdisciplinary integration.[Results]The commonly used methods for the quantitative inversion of elements in soils face challenges when applied on a large scale.Among these,the indirect inversion based on the spectra of plant leaves or canopies is considered the most reliable.Achievements in ecological geochemistry enable the identification of the unique spectral effects of target elements in different plants,which assists in determining the principle of the plant spectrum−based quantitative inversion of elements in soils.[Conclusions]More in−depth research based on big data mining and the physicochemical properties of soils while promoting interdisciplinary integration represents a favorable direction for achieving breakthroughs in wide−area monitoring technology for elements in soils.