Wheat Irrigation-Fertilization Models Of Coastal Slightly Saline Soil

In order to study the mutual relationship between water, fertilizer, and salt in coastal slightly saline soil; and to verify the effects of different irrigation-fertilization models on the saline improvement and on the crops increasing production. The aim is to study and compare the increasing production and reducing salt content effects of the different irrigation-fertilization models(1 and 1.5 times SPV irrigation, SPV was soil pore volume of arable layer; fertilization N-P2O5-K2O:270kg-90kg-180, kg/hm2 and N-P2O5-K2O:270kg-90kg-0, kg/hm2, the basal and dressing application ratio divides into 1:1 and 1:2) and to get the optimal irrigation and fertilization model on coastal slightly saline soil of wheat in Bohai granary technology project area. By comparison to the effects of the different models on reducing salty and on increasing production,The optimum wheat irrigation-fertilization model have been found on coastal slightly saline soil,and it provides scientific basis for the wheat irrigation-fertilization model’s application and diffusion in this region. The main results show that:(1) All irrigation-fertilization models reduced the content of soil salt. From the effect of soil salt content controlling, The model of 1.5 times SPV irrigation+fertilization( N-P2O5-K2O:270-90-0, kg/hm2) with the basal and dressing ratio 1:2 was the optimal irrigation-fertilization model. From the effects of soil environment conditions optimizing, It reduces the content of 0-100 cm soil salt by 1.56%~41.78%, soil EC by 4.25%~36.93%, soil p H by 0.02~0.14 units, soil bulk density by 0.12%~8.12% and improves the soil specific weight by 1.79%~10.21%, soil OM by 0.14%~0.52%, at same time increases UA and IA.(2) Compared with other irrigation-fertilization models, the model of 1 times SPV irrigation+fertilization(N-P2O5-K2O:270-90-0, kg/hm2)with the basal and dressing ratio 1:2 increases the content of soil total nitrogen, alkaline nitrogen and available phosphorus by 0.24%~2.37%,0.67%~13.43% and 1.16%~24.52% respectively, so this irrigation-fertilization model was the best model on conservation of soil nutrients. The fertilization model of(N-P2O5-K2O:270-90-0,kg/hm2)with the basal and dressing ratio 1:2 increases wheat biomass and production greatly in the slightly saline soil by 12.18%, 27.05% respectively. The fertilization models without potassium not reduce the wheat biomass and yield production.Under this fertilization model, 1and 1.5 times SPV irrigation have no significant difference on wheat yield.(3) The model of 1.5 times SPV Irrigation +fertilization(N-P2O5-K2O:270-90-0, kg/hm2)with the basal and dressing ratio 1:2 increases ANRE and APRE increased by 10.00%~155.17%and1.02% ~ 137.52%, respectively. The model of 1 times SPV Irrigation +fertilization( N-P2O5-K2O:270-90-0, kg/hm2) with the basal and dressing ratio 1:2 increases AWUE by50.44%.(4) The model of 1 times SPV Irrigation +fertilization(N-P2O5-K2O:270-90-0, kg/hm2)with the basal and dressing ratio 1:2 is the more cost-effective model. But for the future soil salt controlling, wheat yield stablizing and increasing, apparent fertilizer recovery efficiency improving, The model of 1.5 times SPV irrigation+fertilization(N-P2O5-K2O:270-90-0, kg/hm2)with the basal and dressing ratio 1:2 is the best recommended practical model for local coastal slightly saline soil.