【摘要】 土壤图像灰度值与含水量存在相关性,根据这一特征提出建立灰度值与土壤含水量的数学模型。试验改进了土壤图像灰度值提取的算法,并选取水稻田和花生地两种类型的土壤分别进行了10组重复实验,测定了土壤图像灰度值与其对应土样含水量大小。结果表明:水稻田土壤和花生地土壤所建立的灰度值与含水量的数学模型各不相同,但两类土壤均以三次项的数学模型拟合优度最高。通过模型计算出的土壤含水量与烘干法测得的含水量存在偏差,偏差值小于6%。应用优化后的理论算法和数学模型对土壤含水量的检测结果与土壤真实含水量偏差较低,说明该模型是一种便捷、高效、稳定的土壤含水量测定方法,适于一般的田间土壤含水量测定,可以开发成自动控制灌溉系统的数值分析模型。更多还原

【Abstract】 According to the correlation between gray value of soil image and water content in soil,a mathematical model of gray value and soil water content was proposed.The experiment improved the algorithm of gray value extraction of soil image,and two types of soils as paddy field and peanut field were selected to carry out 10 groups of repetitive experiments,and determined the gray value of soil image and its corresponding water content.The results indicated that the mathematical model of grey value and water content of paddy soil and peanut soil were different,but the best fitting degree of the three-term mathematical model was obtained for both types of soil.The deviation of the soil content calculated by the model and by the drying method was less than 6%.The soil water content tested by optimized theoretical algorithm and mathematical model had low deviation with the real soil water content.It showed that the model was a convenient,efficient and stable method for measuring soil water content.It was suitable for general field soil water content measurement and could be developed into a numerical analysis model of automatic irrigation system.更多还原