摘要
2003—2006年连续3年采用不同小麦品种在不同施氮水平下进行大田试验,于小麦不同生育期采集田间冠层高光谱数据并测定植株氮素含量。根据特征光谱参数-叶片氮素营养-籽粒蛋白质产量这一技术路径,以叶片氮素营养为连接点将模型链接,建立基于开花期高光谱参数的小麦籽粒蛋白质产量预报模型。结果表明:开花期叶片氮含量、氮积累量以及花后叶片氮转运量均能够较好地反映成熟期籽粒蛋白质产量状况;对叶片氮含量和氮积累量的光谱反演,在不同品种、氮素水平和年度间可以使用统一的光谱参数,其中利用红边位置(REPle)和修正型ND705(mND705)可以较好表达叶片氮含量的动态变化,以红蓝边面积比(SDr/SDb)和742nm处一阶微分(FD742)为变量建立叶片氮积累量监测模型效果较好;经独立试验数据的检验表明,以参数REPle、SDr/SDb和FD742为变量建立成熟期籽粒蛋白质产量预报模型均给出理想的检验结果,模型测试精度R2分别为0.854、0.803和0.795,相对误差RE分别为16.4%、18.2%和14.9%;利用开花期关键特征光谱指数可以有效地评价小麦成熟期籽粒蛋白质产量状况。
Three years （2003-2006） field experiment was conducted with different wheat varieties and nitrogen （N） supply, and time-course measurements were made on the canopy hyperspectral reflectance, plant dry mass and its N content. Based on the technique route of characteristic spectral parameters-leaf N nutrition-grain protein yield, and with leaf N nutrition as a link, the prediction models of wheat grain protein yield based on the canopy hyperspectal parameters at anthesis were constructed. The results showed that the wheat grain protein yield at maturity increased with increasing N supply. Plant N nutritional status, such as leaf N content （LNC） and leaf N accumulation （LNA） at anthesis and leaf N transportation （LNT） after anthesis, could well indicate the grain protein yield at maturity. The regression analysis between existing vegetation indices and leaf N index indicated that some key spectral parameters could accurately estimate the changes in leaf N status across a broad ranges of growth stages, N supply and growing seasons, with unified spectral parameters for each wheat cultivar, such as REPle and raND705 for leaf N content, and SDr/SDb and FD742 for leaf N accumulation. The testing of the prediction models with independent dataset indicated that the spectral indices of REPle, SDr/SDb and FD742 could give accurate grain protein yield estimation, and the R2 of REPle, SDr/SDb and FD742 was 0. 854, 0. 803 and 0. 795, with the RE of 16.4%, 18.2% and 14.9%, respectively. Overall, the wheat grain protein yield at maturity could be predicted by the key characteristic spectral indices at anthesis.
出处
《生态学杂志》
CAS
CSCD
北大核心
2008年第6期903-910,共8页
Chinese Journal of Ecology
基金
国家自然科学基金项目(30671215、30400278)
“十一五”国家科技支撑计划资助项目(2006BAD02A07)
关键词
小麦
氮素营养
籽粒蛋白质产量
高光谱遥感
预报模型
wheat
nitrogen nutrition
grain protein yield
hyperspectral remote sensing
prediction model.
