The Appling Study On Prediction Method Of The Water Requirement Of Rice Based On Uncertain Analyse Theory In Jiangdong Irrigation Area

This research is an embranchment of two items of the Post-doctor Scientific Research Fund. One is Water-saving Agriculture and Continuously Making Use of the Water in Heilongjiang , which belongs to the Heilongjiang Province .The other is Uncertain Analysis and Application of Water in Heliongjiang (240009),which belongs to the North East Agriculture University. The water quantity used for agriculture makes up 70%of the total used water of society. Most of water resources used for agriculture have been used for rice irrigation, it makes up 90%of agriculture water per year. With the agricultural modernization and realizing the goal of "two Senior and One excellence", it requires making accurate prediction on time and quantity of irrigating the rice, thus we can irrigate reasonably in order to satisfy crop water requirements.The study provides a prediction method of the water requirment, which fit in Jiangdong irrigation area of rice of Qiqihar through modeling and optimizing for several prediction methods of the water requirment of paddy. We hope to offer the theoretic bases for development of paddy field in the West and sustainable development of the water resource.Seeing from distribution instance of water resource in the whole province, in most areas it has reached or exceeded the ability to irrigate basically, except that it still has potential in Heilongjiang River,Wusulijiang River and riverine areas of Xingkai Lake's border river. The area of paddy field that short of water is 794 million hectares in 2002 and we invested 390 million yuan in fighting against drought. Qiqihar is one of the most important commodity grain bases in our province and it is the fourth large area of paddy field, which plays a great role in getting rid of poor and making fortune for local peasant. At the same time, Qiqihar is the aridest area in our province, especially since the catastrophic flood in 1998, the drought aggravated day by day and disaster of drought has become heavier and heavier. Nenjiang and its branches set the new lowest history record in water level , even some branches have already been dried up. The homeostasis of groundwater was destroyed. More and more pumps can't work and the appearance of funnel has been arisen., therefore it becomes the urgent affairs to make a reasonable and scientific layout of the water resource.Aiming at above-mentioned problems, the task bases on the paddy test-field of Jiangdong irrigation area in the suburb of Qiqihar in Heilongjiang Province and sets up the direct relevant recursive model, auto recursive model of multi-parameters, SETAR, ANN-BP of water requirements of paddy, etc. separately. At the same time we can find out the regularity of water requirement of paddy rice, which is suitable for this area through comparing each model. Through optimizing and studying for systematic model and prediction, the study give out not only the quantitative index and mathematic model of irrigating water and using water but also scientific basis for stabilizing western area of paddy field and making the scientific water-savingirrigation system and regional water-saving planning of irrigation.