Multi-water Conjunctive Optimal Allocation Model Of Irrigation Area Research Under Uncertainty

Recent ly years, the r apid developm ent of global economy, along wit h creat ing huge econom ic benef its the shor tage of wat er resources becom e a w idespr ead problem t o the count r ies all over t he world. The shortage and waste of agr icultur al water m ade agr icult ural product ion in our country suffer a big shock. Ther efor e, reasonable and eff ic ient us e of water r esources is part icular ly im port ant. Im port ant non- engineer ing m easur es for agr icult ural water r esources opt im al configur at ion as t he eff icient use of water r esources can effect ively relieve wat er pr essure. Irrigat ion syst em is a complex and uncert aint y, the convent ional m ethod of opt imal allocat ion of water resources in the applicat ion is limited.In this study, an int erval par am eter two-stage Fuzzy-st ochast ic opt im izat ion model, developing for dis patching the undergr ound and surf ace water systems for different crop in Hong Xing Long irr igat ion under the condit ions of uncert ain ty and complexit y. In the model, t he maximal s ystem benef it was regarded as the object ive f unct ion and t hree m ethods of pr obability dens it y funct ion, discrete inter vals and fuzzy sets were intr oduced int o the two-st age linear programming framework to resolve uncertain issues.First ly, the uncert aint y of water res ources scheduling syst em is analyzed, including the uncertaint y of water supply, water dem and of crops,init ial quant ity of water stor age, rainf all, t he pr ice fluctuat ion of crop and so on. Secondly, thr ee kinds of mathem at ical m ethods are us ed to solve the above m ent ioned uncert aint ies. Becaus e of the obvious probabilit y charact er ist ics of natur al water, dealing uncertaint y of natur al water wit h the probabilit y dens ity funct ion, the occurrence for low, middle and high levels can be assum ed as 0.2,0.6, 0.2; aim ing at the uncert ainty of available water, the available water can be descr ibed as a certain credibility level fuzzy sets by using t he fuzzy planning; expr ess the uncer tain paramet ers which cannot be obtained or cann ot be applied w ith probability distr ibut ion as discret e inter val. Combine the dens it y funct ion, fuzzy sets and discret e int erval wit h two-stage planning to build an inter val- par ameter two-stage fuzzy-stochast ic opt im izat ion model. F inally, get the solut ion of model to obt ain t he opt imal water distribution scheme.In this study, t he tr adit ional int erval two-stage stochast ic progr amm ing model was impr oved and supplemented, the m odel made m ore eff ect ively deal w ith uncert aint y, mor e realist ic water distr ibut ion process. The process of wat er distr ibut ion is mainly divided int o two stages : predef ined stage and punishment phase. Water distr ibut ion progr am r esults inc lude:( 1) the opt imal water dis tr ibut ion tar get, the opt im al allocat ion and shortage of wat er, maximum benef its of water systems.(2) Bas ed on differ ent values of t he dec is ion var iables zij, four kinds of scenar ios of opt im al wat er distr ibut ion pr ogram was obtained, managers can based on plan and r elated polic ies of irrigated, choose the optimum water distribution management under actual program.It could ref lect not only uncert aint ies in water r esources system, but also provided an effect ive linkage between conf lict ing econom ic benef its and the assoc iated penalt ies attr ibuted to the violat ion of the pr edef ined wat er distr ibut ion target. Meanwhile, the r esults in the forms of inter val number, proving a more broad dec is ion space for decis ion makers. Moreover, provide reasonable suggest ions f or irr igat ion managem ent, f or exam ple, the far mer plant ed a large num ber of high- yield and high water consum pt ion of crops such as rice and corn in irr igat ion ar ea and single plant ing structure would lead t o face the r isk of t he decreas e of crop product ion in dry year; Improve the ability of channel wat er will effect ively improve the level of opt im al allocat ion of water resources.