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Wheat is one of China's major crops, wheat and winter wheat planting area accounts for 84% of the total area of ??~ 90%. Shandong Province has a long history of agriculture is one of the main producing areas of winter wheat farmland highest rate in the country, reclamation rate. Planting of winter wheat in the production process, susceptible to stripe rust, insects disasters, lodging and drought, frost and other weather disasters, threats. In recent years, winter wheat production continues to increase, water, fertilizer, plant height, pests and diseases are no longer a major obstacle to the province of winter wheat yield factors, and winter wheat lodging become barriers. Remote sensing monitoring of winter wheat lodging, lodging guide for the agricultural sector in agricultural production after (cultivation and management, harvesting machinery arrangements, etc.), disaster assessment has important research value. Purpose of this thesis is to monitor the spectrometer to obtain spectral data of winter wheat lodging, with the corresponding time remote sensing image and the target area, able to quickly build dynamic monitoring of remote sensing methods wheat lodging. From reality, artificial winter lodging situation, the use of high technology to monitor lodging spectrometer spectral reflectance information, combined with remote sensing image information for the realization of dynamic monitoring provide an important basis. In the paper discusses the winter lodging time, severity, simulated winter wheat lodging situation, the use of high spectrometer winter wheat at different times and lodging degrees circumstances spectral data, and use ViewSpecPro software for data processing, analysis, wheat spectral reflectance curves Figure from Winter Wheat composition changes, the time changes, changes in chlorophyll content and other aspects summarize changes in spectral reflectance characteristics and influencing factors. Study after its winter lodging spectral reflectance first derivative, changes of vegetation index, sum after winter wheat lodging spectral reflectance variations. By comparing a variety of remote sensing data source, select the ALOS satellite panchromatic wave imaging (PRISM) data and multi-band image (AVNIR-2) data as the data source. Using the ALOS satellite imagery, positioning target area variation analysis of image information, combined with spectral information spectrometer, compared to winter wheat after lodging target objects in the image information changes, summarize the spectral reflectance of winter wheat after lodging and remote sensing image variation. Spectral analysis of hyperspectral data and image data, summed up the lodging of winter wheat crown layer spectral reflectance values ??and image brightness variations are as follows: (a) filling stage of winter wheat lodging crown layer spectral reflectance in the visible and near infrared bands increases, lodging The larger the angle the higher the value of the spectral reflectance of winter wheat; grouting before the mid-winter lodging the same degree at the same time the same spectral reflectance, no significant difference; filling maturity period began, filling the late lodging of winter wheat canopy spectral reflectance is greater than before grouting, mid-winter wheat canopy spectral reflectance; proper growth and lodging of winter wheat canopy spectral reflectance of all change over time, and its variation is basically the same, no change in the visible band filling period, near-infrared bands gradually decreased; mature a slight increase of visible light, near-infrared bands gradually decreased; difference lies in the normal growth of winter wheat spectral reflectance in the near infrared band decreased more uniform, while the spectral reflectance of winter wheat lodging reduce the magnitude smaller; Winter Wheat layer of the first derivative of spectral data more prominent after winter lodging characteristic spectral reflectance curve. (2) remote sensing image information indicates that the normal growth of winter wheat and winter wheat lodging an image pixel brightness values ??of characteristics consistent with the red band minimum brightness value, near-infrared brightness of the highest value; winter wheat after lodging the same target area corresponding to the value of remote sensing image brightness in the visible and near infrared bands overall increase, changes in apparent brightness value is near-infrared bands; different brightness values ??of the target area the same band angle change and related lodging, lodging greater the angle, the higher the brightness value. (3) after the lodging of the spectral reflectance of winter wheat and the corresponding variation of the same image information of remote sensing in the visible and near infrared bands are accordingly increased, the increase in the near-infrared bands were greater than the increase in the value of visible light, which increases with the magnitude of the lodging related to the degree proportional to the angle the greater the spectral reflectance lodging and luminance values ??is higher. In this thesis, high spatial resolution remote sensing image, positioning analysis target area image information, combined with the spectrometer spectral information, compared to winter wheat lodging crown layer spectral reflectance and remote sensing image brightness values ??change, the study found the target area can change the image brightness values characteristics of winter wheat lodging time dynamic monitoring, disaster level, yield loss forecast for the agricultural sector to provide fast and accurate information. This thesis is to achieve a large area of ??winter wheat lodging disaster dynamic monitoring provides a strong basis.
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