基于RGB的黑土有机质快速测定方法研究  

Rapid Method for Estimating Organic Matter of Black Soil Based on RGB

作　　者：吴才武[1] 杨越[1] 夏建新[2] 

机构地区：[1]河北民族师范学院资源与环境科学学院,河北承德067000 [2]中央民族大学生命与环境科学学院,北京100081

出　　处：《土壤通报》2016年第4期853-859,共7页Chinese Journal of Soil Science

基　　金：承德市科学技术研究与发展计划项目(20155004);承德市财政局课题(CZ2013011)资助

摘　　要：有机质是土壤的重要组成部分,是判定土壤质量动态变化的重要标准。以操作简单、价格便宜、易于获得的数码相机作为工具,提取黑土表面颜色信息,定量化研究黑土表面颜色与其有机质含量之间的关系。研究结果表明,通过灰度直方图统计来获取图像最大值的方式可以有效消除因主观因素和非土壤物质对图像RGB值造成的影响,显著提高了与有机质的相关性。在RGB三波段中,R波段灰度值与有机质相关性最高,其相关系数为-0.7432。对RGB三波段进行相应数学变换后,其中倒数回归模型的预测效果最好,其R2=0.7339,RMSE=0.3907,检验结果 R2val=0.7405,RMSEval=0.265。数码相机获取的RGB三波段建立的预测模型,稳定性强,预测能力高,可作为黑土区有机质快速测定的可选工具。Organic matter plays a key role in soil and is used to determine soil quality. The article extracted the color information of Black Soil surface by the digital camera which was easy to operate, cheap and accessible, and studied the relationship between organic matter content and surface color of Black Soil. The correlation analysis showed that the three bands of RGB obtained by the digital camera had a high correlation with soil organic matter （SOM）. The red image-intensity value among three values from the digital camera showed the largest correlation with SOM, and the correlation coefficient （r） was up to 0.7432. The RGB gray value of soil surface would increase and decrease due to the heterogeneity and non-soil material, which had a great influence on the extraction of true RGB values. It would be a good way to eliminate tile influence of subjective reasons or non-soft sufistances on tile image ffGff values tfirougfi gray histogram statistics to obtain maximum, and the correlation with organic matter significantly improved when used the maximum as the image RGB values. The reciprocal regression model expressed the best resuh among three bands by mathematical transformation, and the coefficients of determination （R2） of the model was 0.7339, RMSE was 0.3907, with R2rd = 0.7405 and RMSErd = 0.265. So, the digital camera that built the model that is quite good instability and predictability, and can be used as an alternative tool for rapid and accurate estimation for organic matter content of Black Soil.

关 键 词：可见光 有机质 数码相机 土壤颜色 

分 类 号：S158.2[农业科学—土壤学]