首页>>学术检索

数字图像技术在作物氮营养诊断中的应用研究

标题: 数字图像技术在作物氮营养诊断中的应用研究
英文标题: Diagnosis of N Nutrient Status of Crop Using Digital Image Processing Technique
作者: 张立周
出版时间: 2011-01-01
所在大学: 河北农业大学
关键词: 数字图像,氮营养诊断,水肥耦合,冬小麦,夏玉米
英文关键词: Digital image,Nitrogen nutrient diagnosis,Couple effect of water and fertility,Winter wheat,Summer corn
论文级别: 硕士
学位: 学位论文
导师: 王殿武%张玉铭
专业: 土壤学
提交时间: 2011
摘要: 本文于华北平原区栾城试验站进行了冬小麦与夏玉米田间试验,利用数码相机获得冬小麦和夏玉米冠层图像,结合土壤、植株快速测试技术,研究了数字图像技术应用于冬小麦和夏玉米氮素营养诊断上的可行性,并对数字图像技术与土壤、植株快速测试技术相结合应用于冬小麦和夏玉米农田氮肥推荐进行了探讨;另外,于河南封丘对水肥耦合下冬小麦冠层的色彩参数变化规律进行了研究.主要研究结果如下:1、地面数字图像技术可以作为冬小麦和夏玉米氮素营养的诊断方法.冬小麦在拔节期与孕穗期冠层的绿光标准化值G/(R+G+B)与土壤、植株氮营养测试指标均有极显著的相关关系.在地面数字图像处理得到的八个图像色彩参数中,以冠层绿光标准化值G/(R+G+B)与施氮量、叶绿素仪读数、茎基部硝酸盐浓度、植株全氮和拔节前供氮量等土壤、植株氮营养测试指标的相关关系最好.拔节期是用数字图像技术作为冬小麦氮素营养诊断的关键时期.在夏玉米6叶期,玉米冠层数字图像色彩参数指标B/(R+G+B)、G/B、R/B、B/L均与施氮量、叶片SPAD值、植株硝酸盐浓度、植株全氮含量、0~90 cm土壤硝态氮含量存在极显著的线性相关关系,其中B/(R+G+B)与各营养参数的相关关系最好,其次是B/L.夏玉米6叶期可作为应用数字图像技术进行氮素营养诊断的关键时期,而蓝光标准化值B/(R+G+B)是进行夏玉米氮素营养诊断的最佳冠层图像色彩参数指标.2、地面数字图像获取时,可将数码相机与冬小麦冠层成30~60°角度进行拍摄.相机所得的绿光标准化值与相机本身的像素间存在一定的关系.3、应用地面数字图像技术与土壤植株测试技术结合进行冬小麦氮肥推荐时,根据冬小麦拔节期硝态氮含量与绿光标准化值G/(R+G+B)建立方程,根据此方程可对冬小麦拔节期进行推荐施肥供氮不足时,推荐追肥量为100150 kg(N)·hm-2;供氮正常时,推荐追肥量为50100kg(N)·hm-2;供氮过量时为050kg(N)·hm-2.应用地面数字图像技术与土壤植株测试技术结合进行夏玉米氮肥推荐时,根据夏玉米6叶期硝态氮含量与蓝光标准化值B/(R+G+B),建立了推荐施肥方程,根据此方程可对夏玉米6叶期进行推荐施肥.供氮不足时,推荐追肥量为大于230 kg(N)·hm-2;供氮正常时,推荐追肥量为180 230kg(N)·hm-2;供氮过量时为150180kg(N)·hm-2.4、水肥耦合下,对所得的数字图像色彩参数的数据进行数据分析,发现在水肥耦合条件下,也可以用数字图像技术进行冬小麦氮素营养诊断.数字图像色彩参数指标与施氮量之间是存在着极显著的相关关系.在水肥耦合条件下,水分不同所得到的数字图像色彩参数之间也存在差异,即随着施氮量的变化,不同水分状况下的色彩参数有一定的规律性.施氮量低时,水分的作用是正面的,而施氮量高时,水分的作用是负面的.
英文摘要: In this thesis, the experiment was conducted in Luancheng suburb where winter wheat and summer corn are planted. The possibility of using digital image analysis method for plant N status diagnosis was studied, and the standard method of digital image acquisition and saving was established. In addition, aerial true color and infra-red images analysis method, which combined with soil and plant N rapid test, was studied for N recommendation in a large scale.And the color parameter indexes of wheat canopy images at effect of water and fertility was studied. The main results are as follows:1、The digital image processing technique could be used of N status detection of winter wheat. The results show significant inverse relationships between greenness intensity and canopy total N, SPAD readings, plant nitrate concentration and nitrate N content in 090 cm soil at jointing stage and booting stage. Compared with other seven green index of plant canopy, the normalized greenness intensity G/(R+G+B) was much better because of its better correlations with canopy total N, SPAD readings, plant nitrate concentration and soil N supply. In booting stage,the correlations are not so significant as those in jointing stage. The jointing stage is crucial period with G/(R+G+B) as the index for the N nitrogen diagnosis using digital image processing technique.In the 6-leaf stage, color parameter indexes of B/(R+G+B), G/B, R/B, B/L are significantly linearly correlated with N application level, leaf SPAD, stem sap nitrate concentration, plant total N content and nitrate N content in 090 cm soil (P<0.01). And B/(R+G+B) presents most significant correlation, and B/L is next to it. In 10-leaf stage, the correlations are not so significant as those in 6-leaf stage. The results suggest that it is feasible to use digital image processing technique to diagnose N nutrient statues of summer corn. The 6-leaf stage is crucial period with B/(R+G+B) as the index for the N nitrogen diagnosis using digital image processing technique.2、For taking digital image of wheat canopy in field, the angle between digital camera and ground could be 30~60°.The G/(R+G+B) from three kinds of cameras have certain relevance and its pixels.3、Field digital image analysis method combined with soil and plant rapid test could be used for N fertilization recommendation. According to the winter wheat jointing stage nitrate content .According to this equation can on winter wheat jointing stage to recommend fertilization. When deficit of N supply,ertilization recommendation is 100150 kg ( N )·hm-2 , when N supply , ertilization recommendation is 50100 kg(N)·hm-2,When excessive N supply,ertilization recommendation is 050kg(N)·hm-2.Field digital image analysis method combined with soil and plant rapid test could be used for N fertilization recommendation. According to summer corn 6 leaf stage nitrate in fertilizer, According to this equation of summer corn 6 leaf stage to recommend fertilization. When deficit of N supply,ertilization recommendation is 230kg(N)·hm-2,when N supply,ertilization recommendation is 180230 kg(N)·hm-2,When excessive N supply,ertilization recommendation is 150180kg(N)·hm-2.4、In couple effect of water and fertility, on the digital image colour of income data data analysis parameters.The result is that diagnosis of N nutrient status of wheat using digital imageprocessing technique in couple effect of water and fertility. And the relationships between color parameter indexes of wheat canopy images and N application level, wheat yield were determined. The results show that color parameter indexes are significantly linearly correlated with N application level and wheat yield. In couple effect of water and fertility color parameter indexes was little different at the different water. Namely the variety that measures along with N application level, under the different humidity condition of the color parameter has certain regulation.When amount of nitrogen was low, the function of humidity was negative when the function of humidity was positive, while high N application level.