土壤学报2019，Vol.56Issue(1)：78-89,12.DOI:10.11766/trxb201802250012
测色仪与中国标准土壤色卡测定土壤颜色比较——以川中丘陵区为例
Comparison between Colorimeter and New Standard Soil Colour Chart of China in Determining Munsell Color of Soils——A Case Study of Central Sichuan Hilly Region
摘要
Abstract
[Objective]Soil color is a reflectance spectra characteristic of the soil in the visible light band and also a kind of visual perception. The Munsell color chart is a traditional tool to determine Munsell color of soils, however, soil color determination by color charts may be subjective due to the impacts of human subjective consciousness and environmental conditions. With advancement of the optical technology, numerous instruments have been developed one by one for determining soil colors, such as spectrographs, digital cameras, and even more convenient mobile phones that can all be used to determine soil colors.However, spectrometers are often quite expensive and bulky, and digital cameras and mobile phones are not so easy to get calibrated. So portable colorimeters pop up as a new type of tool that has the advantages of being small in size, easy to carry, and moderate in price. The use of colorimeters to determine soil colors helps to avoid subjective factors and some objective environmental factors, and hence improves work efficiency. The object of this study is to compare the New Standard Soil Colour Charts with two types of portable colorimeters in determining Munsell color of soils, in an attempt to find out differences between them and select a superior one for determination of Munsell color of soils.[Method]A total of 97 soil samples of 27 soil series were collected in the Central Sichuan hilly region, for determination of Munsell color after they were purged of plant and animal residues, air-dried, ground to pass a sieve, and mixed to get homogenized, separately. Each sample under went three treatments, that is, determination of Munsell soil color, with the New Standard Soil Colour Charts, Nix and CM600 d, separately. The data of hue, value and chroma of soil Munsell color could be achieved directly via ocular estimation of the sample against the New Standard Soil Colour Charts, the use of CM600 d, and the use of the color conversion formula to process the CIE XYZ data obtained with NIX. Then with the help of statistical parameters and rules for grading differences in Munsell soil color, comparison was done of the data obtained with the three different methods.[Result]The hue of the air-dried soil in Central Sichuan hilly area lingered mainly in YR, with5 YR and 10 YR appearing the most frequently, or 33 and 30 times, respectively. The soil classified as purple soil in the Chinese Soil Genetic Classification System, after being air-dried, did not show any hue of RP, and lingered in the range of 4～8 in value and in the range of 2～6 in chroma, with "value/chroma" ratio being 5/3, 5/4, 6/4 and 7/4, the most frequently, indicating that the soils tested were quite high in value, but low in chroma. With the result of the ocular estimation method as reference for comparison, the Munsell soil color obtained with the colorimeter method tended to be yellowish and agreeable value and chroma. The RMSE of hue, value and chroma measured with the CM600 d was 1.74, 0.98 and 0.97 unit, respectively, and that with the NIX was 2.04, 0.57 and 0.88 unit, respectively. The difference between the ocular estimation method and the colorimeter methods in Munsell soil color could be graded into"Faint", "Distinct"and"Prominent", which was 90.72％, 8.25％ and 1.03％, respectively, for CM600 d and 84.54％, 14.43％ and1.03％, respectively for NIX.[Conclusion] The two kinds of colorimeters are useful to help researchers measure Munsell soil color, and improve accuracy of the measurement, too. The Nix method is closer to the ocular estimation method in measuring value of the Munsell soil color and moreover superior in price.关键词
土壤Munsell颜色/色卡/测色仪/色系转化Key words
Munsell color of soils/Color charts/Colorimeter/Color system conversion分类
农业科技引用本文复制引用
陈剑科,袁大刚,晏昭敏,吕扬,翁倩,付宏阳,张楚,王昌全,张敬昇..测色仪与中国标准土壤色卡测定土壤颜色比较——以川中丘陵区为例[J].土壤学报,2019,56(1):78-89,12.基金项目
国家自然科学基金项目(41671218)和国家科技基础性工作专项项目(2014FY110200A12)资助 （41671218）
Supported by the National Natural Science Foundation of China (No. 41671218) and Basic Work of the Ministry of Science and Technology of China(No. 2014FY110200A12 ) （No. 41671218）
