Research On The Precision Of Variable-rate Fertilization In Precision Agriculture

The precision agriculture or precision farming is the hot field of the nationalagricultural research of science in recent years, which is the substitute word ofthe future agriculture as one form of presentation or one part of informationagriculture in the recent hot research in USA, Canada, and the British. Thecore of the precision farming is the precision location or variable processsupported by GPS, GIS, and RS etc. With the development of the precision farming, the researches andapplications of variable fertilization technology are coming to issue morepeople's attentions. The system of variable fertilization technology isbecoming the most important part of technology system in precision farming.The researches of variable farming are based on the differences of soil nutrient.The traditional methods of fertilization select a large area farmland forsampling and examining of soil and calculate the unit of fertilization of theselected farms, which neglect the differentiations of soil nutrition in space andmake less fertilization of the lower fertility soil, more of the higher soil. In fact,the soil is "variable in different area". That is variable and non-uniform ineven a smaller farm. The applications of variable fertilization technology in precision farming,according to the different pieces of farmrequirements, relatively distribute thedifferent prescription and different quantum fertility of real-time controltechnique. According to the space difference in distribution, adjust measures to -81-吉林大学硕士学位论文　local conditions thin the larger piece of farm and sample, measure and decidethe smaller pieces of farm for the usage of the fertility based on the needs so asto reduce the cost , promote the production and boost the utilization ofagricultural equipments, lessen the pollution. So, for better economic profitsand environmental benefit, adapt to the needs of different areas, crops and thedifferent growth environment of different crops, variable prescriptionfertilization is our development direction for future fertilization. The precision of fertilization machine in variable fertilization technologysystem has the vital effect in the process of variable fertilization. After thedeciding of fertilization, different units of farm adapt to the differentfertilization quantity, which differ the every unit has the same quantity offertilization as what we've done, so as to finally reduce the devotion andpromote the economy of the operations. However, if the control precision offertilization machine can't be guaranteed, it will definitely wastes the fertilizerand makes the "precision"lose the meaning of the precision agriculturalsystem. Therefore, the research of units of fertilization has the importantmeaning. The research in this paper is based on the item of the academic committeeof Jilin province: part of the research of precision agricultural variablefertilization technology (no.　２００００２０１－３－１). This research includes thefollowing parts: create the GIS database of the soil nutrition in the middle partof plantation in Jilin province; create the fertilization expert system accordingto the relative plantation in the middle part in Jilin province; the research ofthe precision location so as to location precisely the operation units; create theauto variable fertilization system; the research of auto variable fertilization -82-Ａｂｓｔｒａｃｔ　　machine. The technological guideline units is 80~400kg/ha without adjustmentand the error is not higher than 8%. The research of the fertilizationprecisionin fertilization system is the emphasis in this paper. This paper is imbursedby the development office of Jilin province agriculture "the examination anddemonstration of variable fertilization technology, Yushu city, Jilin province.The variable fertilization technology is the most part of t...