The Research Of Establishing The Mathematics Model Of Sludge Fertilizer Production Under The Condition Of Cotton's Under-film Drip Irrigation

Scarce water resources are important limiting factors for agricultural production and environmental melioration in arid and semiarid regions. The under-film drip irrigation has gained widespread popularity as an efficient and economically viable irrigation method and has provided the new research mentality and the method for the arid and semiarid regions water and soil resources' development use.The technology of applies fertilizer and the technology of drip irrigation to unify, is using the drip irrigation systematic as the tool of applies fertilizer.And in the quantity fertilizer, the applying fertilizer time and applies fertilizer aspects and so on uniformity to be possible to achieve the high precision, thus causes the drip irrigation crops to obtain the good output and the economic efficiency. This study is under the condition of nder-film drip irrigation,and definite cotton's output to the nitrogen ,the phosphorus and water's interdependence relations as well as quantifying which applies fertilizer with the mathematical model research. This both can save the fertilizer, and can satisfy the nutrient which to a certain extent the cotton different periods of growth need, also avoided the unnecessary fertilizer causing the pollution to the soil.The main research is following:(1)The experiment was carried on in the Shihezi country agriculture technology zone in 2007, which take the nitrogenous, the phosphate and the water as the variable factors,using"3414"design proposal.In this experiment"3414"are refers to the nitrogen (N), the phosphorus (P) and the water (W) three factors, each factor supposes 4 levels, altogether 14 processing.And pure N was 0, 150, 300 and 450 kg hm^-2,pure P was 0, 60, 120 and 180 kg hm^-2 and the irrigation quantity was 2400, 3600, 4800 and 6000 m³hm^-2. The result indicates that when fixed two factors one was changing, in certain scope amount used, the output increases along with the nitrogen ,the phosphorus and the water increases, when increases after the ration, then increases the nitrogen ,the phosphorus and the water the quantity instead to have the drop tendency.(2) Through multiple regression analysis method obtains non-linear multi-dimensional applies fertilizer mathematics model is : Y=1120.11+5.644N+3.074P+1567.467W-0.0112N2+0.0490NP-0.501NW-0.0201P2-1.771PW-138.211W2After the regression surface analysis indicated that the nitrogen, the phosphorus, the water most superior response value respectively is 292.701, 119.121, 4.494. When substitution above equation obtains the output optimum value is y=6311.916. This experimental result showed that the nitrogen, the phosphorus, the water best amount used is:N 292.701 kg hm^-2, P 119.121 kg hm^-2, W 4494 m³hm^-2.The model difference relatively is between 0.26% and 4.27%,which can match the fact and be feasible.(3) Because the cotton is to the nitrogen sensitive plant, the nitrogen has the decisive influence to cotton's growth,Therefore through 2007 experiment, 2008 experiment we designed the variable as the nitrogen increasing rate r and 5 levels, as 0.140(N0'),0.142(N1'),0.144(N2'),0.146(N3'),0.148(N4'). According to the experiment we have established the tiptop yield exponential fertilization model which is N_m= N₀ (e^0.146×t-1)- N_m-1, When the cotton field executes the nitrogen (N) quantity is 310.39kg hm^-2, and the tiptop yield which is 7080.087 kg hm^-2 .In which N0 =8.512×10^-5kg hm^-2 is the N content of plant at first, r is the relative growth speed daily of plant, t is the fertilization number of days (starting from sowing), m is the fertilization number of times, N_m is the quantity fertilizer applying, N_m-1 is the quantity fertilizer applying last time. The result of the model's checkout shows that it's remarkable or extremely remarkable in the variance analysis and the correlation of coefficient, and the effect of imitation between the theoretics and the fact is better, in which the correlation coefficient is 0.97～0.98. Therefore the fertilization mathematics model can apply and extend in production..