稻纵卷叶螟为害下水稻孕穗期的光谱特征及生物量分析
时间:2018-07-10 15:14 来源:毕业论文 作者:毕业论文 点击:次
| 摘要：为了获得稻纵卷叶螟不同为害程度下，表征水稻叶片为害程度的敏感波段和水稻生物量变化特征，本研究拟从水稻光谱反射率的变化入手，提取受害作物光谱曲线中的光谱吸收特征，找到表征水稻叶片危害程度的敏感波段和水稻生物量变化特征，为稻纵卷叶螟为害程度的遥感监测提供理论指标与方法。利用ASD光谱仪、SPAD仪、植物冠层分析仪AccuPAR 监测稻纵卷叶螟不同为害等级状况下，水稻孕穗期的稻叶的光谱特征，并测定水稻的生物量变化，探讨稻叶光谱、生物量与害虫发生程度之间的规律，为遥感监测和预测稻纵卷叶螟为害程度提供理论基础和预报指标。选择能反映稻纵卷叶螟不同为害程度的敏感波段，建立为害程度的预测模型；同时，从定性研究受害程度对水稻光谱反射率的影响大小关系及稻纵卷叶螟的不同为害等级与水稻生物量之间的关系。在水稻孕穗期，在红外光区760-1000nm波段范围内受害等级与反射率间呈现出显著的负相关关系。将敏感波段760nm波段处的反射率及其组合进行叶片受害程度的线性反演，得到稻纵卷叶螟为害叶片程度的初步诊断模型为y =-26.864x +16.871，R² = 0.397。水稻受稻纵卷叶螟为害后，在叶片光谱的反射率上有明显表现，可以利用光谱特征来监测稻叶的受害程度。25568 毕业论文关键词：稻纵卷叶螟；光谱特征；诊断模型；生物量 Analysis of the spectral characteristics and the biomass of rice damaged by Cnaphalocrocis medinalis at booting stage Student majoring in Plant Protection An chao Tutor Wang cuihua Abstract: In order to obtain the sensitive bands and the characteristics of rice biomass under different damage degrees of Cnaphalocrocis medinalis, we studied the changes of spectral reflectance of the rice leaf under different damage levels, extracted the characteristics of the spectral absorption from the spectral curves of damaged rice, identified the sensitive bands and rice biomass changes, and provided the theoretical indexes and methods for remote sensing monitoring the damage degree of Cnaphalocrocis medinalis. AccuPAR is used to monitor the spectral reflectance of rice leaves at rice booting stage under different damage levels using ASD spectrometer, SPAD instrument and plant canopy analyzer, and the changes of rice biomass were measured. Spectrum, biomass and pest damage degree, and provide the theoretical basis and forecast index for remote sensing monitoring and prediction of the damage degree of Cnaphalocrocis medinalis. Selecting the sensitive bands to reflect the damge degrees of Cnaphalocrocis medinalis, building damage degree diagnostic model. Hereby studying the effect of the damage degree of Cnaphalocrocis medinalis on spectral reflectance of rice plants and biomass of rice. At rice booting stage, there is a significant negative correlation between the damage level and the reflectivity in the range of 760 - 1000nm band in the infrared region, and linear inverting the reflectivity of 760nm band and its combination, obtaining the initial diagnosis model predict leaf damage degree: Y = -26.864x + 16.871, and R² = 0.397. After damaged by Cnaphalocrocis medinalis, the spectral reflectivity of rice leaf is obviously different, and the spectral characteristics could be used to monitor the damage degree of rice leaf. Key words:Cnaphalocrocis medinalis；Spectral features；diagnostic model；Biomass 目 录 摘要1 关键词1 Abstract1 Key words1 引言2 1 材料与方法3 1.1 试验区水稻的生长状况及受稻纵卷叶螟为害情况3 1.1.1 试验田3 1.1.2试验水稻品种及试验设计3 1.1.3 供试虫源 3 1.1.4 罩笼设置3 1.1.5 接虫时间及测定方法3 (责任编辑：qin) |