【作者】 宋海燕；

【导师】 何勇；

【作者基本信息】 浙江大学 ， 农业机械化工程， 2006， 博士

【摘要】 自20世纪90年代以来,随着全球定位系统(GPS)、地理信息系统(GIS)、遥感技术(RS)、变量处理设备(VRT)和决策支持系统(DS)等的发展,精细农业作为一种经营现代农业的新技术应运而生了。该技术的核心是获取农田小区作物产量和影响作物生长的环境因素(如土壤结构、地形、植物营养、含水量、病虫草害等)实际存在的空间和时间差异性信息,分析影响小区产量差异的原因,采取技术上可行、经济上有效的调控措施,区别对待,按需实施定位调控的“处方农作”。 精细农业是现代高新技术,特别是信息技术在农业生产上的应用,是一系列高新技术的集成应用,主要包括信息获取系统、信息处理系统与智能化的农业机械作业。其中信息获取系统是开展精细操作实践的基础和依据,因此系统全面地研究适合我国精细农业实践的田间信息(土壤信息、作物信息、产量及品质信息)的获取技术和处理方法是非常必要的。 本论文针对国内外在田间信息获取技术上存在的一些问题和不足,结合我国的实际情况,采用了3因素(氮、磷、钾肥)二次正交回归设计方法,对油菜田中的田间施肥情况设计了施肥水平,使三种营养元素分别处于偏少、正常和过量的状态。对油菜田中的土壤信息、油菜生长过程中的作物信息、土壤信息与作物中的叶绿素含量信息、土壤信息与油菜籽的产量和品质信息之间的关系进行了系统、深入的分析。主要研究内容和结论如下: 1)采用ASD公司的便携式光谱仪研究了测量覆盖面积对土壤光谱特性和土壤含水率的影响。并从几何学的角度进行了理论分析,建立了通过测量几何位置确定测量覆盖面积的数学模型。为今后使用该仪器在田间测量时,减少背景信息,选取最佳测试几何位置奠定了基础。 2)研究了采用尼高力公司NEXUS智能型傅立叶红外光谱仪采集的经简单处理过的土壤(模拟田间土样)光谱特性,建立了土壤光谱吸光度与土壤中的氮(N)、磷(P)、钾(K)、有机质(OM)和pH之间的定量分析模型。结果表明,采用近红外光谱仪经一阶导数处理可以很好地预测简单处理土样中的OM和pH含量,预测相关系数可以达到0.8以上。在对土壤OM含量的定量分析过程中,提出了将正交信号校正方法(OSC)作为谱图预处理方法,使预测相关系数达到0.89,大大提高了模型的预测精度。在对土壤中N含量的预测中,发现土壤颗粒大小严重影响到土壤N含量的预测能力。对P、K的预测效果并不是很好,预测样本的预测相关系数分别为0.661和0.721,还有待于进一步的研究。 3)在对油菜生长状况的监测过程中,采用SPAD502叶绿素仪研究了同一叶片、同一植株不同测量部位SPAD值的分布情况,并采用ArcView 3.2地理信息系统软件中的空间分析模块直观、准确地对其进行了表达。结果表明测量部位不同,SPAD值也不同。根据本试验的要求,对从顶部算起的第三片叶进行了跟踪测量,系统、深入地分析了油菜叶片的SPAD值随生长阶段、施肥情况的变化规律。得出蕾苔期与开花期过渡时期是进行田间氮肥检测和管理的最佳时期。对今后该油菜田中的氮肥管理提供了一个参考基准。 4)采用ASD公司的便携式光谱仪在室外分析了油菜叶片的光谱特性,找到其最佳敏感波段为676nm和684nm,相关系数达到0.923。对油菜叶片的SPAD含量与“红边位置”和“绿更多还原

【Abstract】 With the development of GPS, GIS, RS, VRT and DS, precision agriculture as a new technology has emerged since 1990s. The kernel of this technology is to obtain the yield production of the small section, the spatial and temporal information of the environmental factors （soil structure, topographic form, crop nutrition, water content and plant diseases and insect pests et al.）, which influence the growth of the crop, and then adopt the appropriate measurement to realize "prescription farming" by analyzing the reasons of these factors.Precision agriculture is an integrated application of the advanced technology, especially the information technology in the agricultural production. It consists of information obtain system, information treatment system, and intelligent mechanization of farming. Information obtain system is the base and thereunder of the precision agriculture in the practices of its operation, so it is very necessary to systemically and roundly analyze the obtain techniques and disposal methods of the field information （soil information, crop information, yield and quality information of the crops）.Considering the actual situation of our country, and the problems and deficiencies of the present technology in the information obtain system, we systemically and roundly analyzed the soil information in the oilseed rape field, crop information in the growth of the oilseed rape, the relationships between the soil information and chlorophyll content, oilseed rape yield and quality information. Quadratic regression orthogonal design was applied in this research to design the fertilization level. Three factors （nitrogen fertilizer, phosphorus fertilizer, kalium fertilizer） were considered in this research, and the field was in the condition of deficiency fertilizer, normal fertilizer and excessive fertilizer manually. The main contents and conclusions were as follows:1) The influence of measurement area to soil spectral properties and water content prediction were analyzed in this research by using the handheld spectrophotometer （ASD）. Geometric method was also been used to validate the above conclusion, and the mathematic model was founded according the position of the spectrophotometer to the object in the process of the measurement. This model can be applied in the outdoor measurement. It can estimate the measurement area according with the measurement height, or estimate the measurement height according with the measurement area. It is obviously that it can avoid the influence of the background information during the process of the spectra collection.2) Spectral properties of the raw soil samples （in the natural condition, soil samples was simply treatment） were analyzed by using NEXUS intelligent Fourier transform （FT） infrared spectorscopy, and the quantitative analysis model was founded to the soil nitrogen （N）, available phosphorus （P）, available kalium （K）, organic matter （OM） content and pH. The result shows that it can predict OM content and pH value commendably with the l_st derivate spectra, and the correlation coefficient is up to 0.8. Orthogonal signal correction （OSC） method as a new pretreatment method to the spectra wasapplied in this research during the processes of the OM content prediction. It can improve the prediction ability greatly, and the correlation coefficient achieved to 0.89. During the analysis of the nitrogen content prediction, we found that particle size influence the nitrogen prediction ability greatly. The prediction ability to the P and K are not satisfied as our expected, the correlation coefficient is 0.661 and 0.721 respectively, so it needs a further research.3) SPAD 502-chlorophyll meter was used in this research to analyze the variability of chlorophyll content during the growth stage of the oilseed rape. Spatial analysis module of Arc View 3.2 software was used to analyze the spatial distribution rule of the SPAD values, which can reveal the distribution of SPAD intuitionisticly and accurately. The result shows that different measurement part has different SPAD values. The third leaves counted from the above were selected as our research object. The variation law of SPAD values in different growth stage and different fertilizers levels was detailed analyzed in this research. The result shows that interim of the bud and anthesis is the best time for nitrogen management. It will be helpful for the nitrogen management to this field.4) Spectral properties of oilseed rape leaves were analyzed in this research by using handheld spectrophotometer. The result shows that the sensitive brands to SPAD values are 676nm and 684nm, respectively, and the correlation coefficient is 0.923. The relationship between the SPAD value and the red edge and green edge was also analyzed. The result shows that two variables （red edge and green edge） can better predict the SPAD values of the oilseed rape leaves than the one variable （red edge）.5) The quantitative analysis model was founded to soil fertilizer and SPAD values, and the result shows that nitrogen fertilizer is positively correlative to SPAD values. This result futherly demonstrated that SPAD could reflect the nitrogen fertilizer. The quantitative analysis model was also founded to soil fertilizer and yield of oilseed rape. The result shows that nitrogen fertilizer is positively correlative to the yield. The yield increased with the increase of the nitrogen fertilizer. Kalium fertilizer is sensitive to the yield when the kalium fertilizer is deficient, that is, when the kalium fertilizer is deficient, the yield is lower, while when it is in the normal or excessive condition, the yield has no more significant change. Phosphorus fertilizer has no more significant role to the yield in all stage.6 ) Quadratic regression orthogonal design was used to analyze the relationships between the oil content of oilseed rape, glucosinolate content, and erucic acid content and the fertilizer. The result shows that nitrogen fertilizer affected the oil content greatly. When the nitrogen fertilizer was excessive, nitrogen fertilizer is negative correlative to oil content and glucosinolate content. Excessive phosphorus fertilizer can reduce the glucosinolate content, and kalium fertilizer is significant to erucic acid at the 0.1 levels. Erucic acid content increased with the increase of the kalium fertilizer. The interaction of the fertilizer to oilseed rape quality was also analyzed in this paper. The result shows that interactions of the nitrogeous fertilizer and kalium fertilizer affect the oil content greatly, and the interactions of the phosphorus fertilizer and kalium fertilizer affect the glucosinolate content and erucic acid content greatly.7) To improve the yield and quality of the oilseed rape, nonlinear programming model was founded in this paper to find the best scheme of fertilizer. The result shows that different research object has different conclusions. Excessive nitrogen fertilizer can improve the yield of oilseed rape, while it will decrease the oil content and increase the glucosinolate content at the same time. Excessive phosphorus fertilizer can decrease the glucosinolate content, but it will affect the oil content of the oilseed rape. In order to realize the objective of the high yield and quality, this paper suggests that when the the urea （46%） is between the 22.23-29.87kg, superphosphate （powder, 16%） is between the 1.7-1.84kg, and potassium chloride （60%） is between the 1.71-16.67kg in a unit of area, the lower erucic acid content and higher oil content will be obtained, relatively. When the the urea （46%） is between the 28.53-48.76kg, superphosphate （powder, 16%） is between the 43.5-53.86kg, and potassium chloride （60%） is between the 23.1-31.62kg in a unit of area, the lower glucosinolate content and higher yield will be obtained, relatively.更多还原