Influence Of Optimal Fertilization On Rice Nutrient Uptake, Grain Yield And Soil Nutrients In Nansi Lack Area

For finding an optimal rice fertilization model, the experiment was conducted in ShuangHan village, Yutai County, Shandong Province. According to the fertilization of farms’ practice and the characteristics of rice fertilizer requirement, seven different fertilization model were designed for this study, CK, FP(N-P2O5-K2O:345-172-135 kg/hm2), OPT(NP2O5-K2O: 235-96-45 kg/hm2, nitrogen fertilizer was common urea), OPT-PK(N-P2O5-K2O:0-96-45), CRN+OPT-PK(N-P2O5-K2O: 235-96-45 kg/hm2, nitrogen fertilizer was controlled release urea), 80%CRN+OPT-PK(N-P2O5-K2O:188-96-45 kg/hm2), OM+80%OPT(N-P2O5-K2O:188-81-36,OM, 3000kg/hm2). By researching the effects of rice plant height, biomass, and grain yield, fertilizer use efficiency and soil nutrient of different fertilization models, In order to provide theoretical and practical support of rice optimal fertilization in nansi lake area. The results were as follows:(1) Compared with common urea, controlled released urea featured more on rice growth, rice plant height and rice shoots dry matter were better than common urea. Reduced chemical fertilizer and increased organic fertilizer was benefited to rice growth.(2)Controlled release urea superior to the common urea on NPK element accumulation and distribution in rice stem, leaf and grain, the grain NPK uptake increased by 15.83%, 23.24% and 23.24%, respectively. Reduced chemical fertilizer and increased organic fertilizer improved the nutrients absorbing and transforming to grain.(3) In this experiment, high NPK fertilizer(345-172-135 kg/hm2) did not reach the effect of rice yield increase, and on nitrogen provided caused the rice yield decreased by 31.06%; under equal NPK amount(235-96-45 kg/hm2) inputted, the controlled release urea with recommended P K fertilizer could increase rice yield by 8.75% than the common urea with recommended P K fertilizer; 20% of controlled release urea reduction with recommended NK fertilizer had no difference.(4) Compared with common urea, controlled release urea with recommended P K fertilizer improved NPK utilization rate significantly, and reduced the controlled release urea 20% could improve nitrogen utilization rate by 21.40%, but the P K utilization rate had no significantly changed; Compared with the recommended fertilization, reduced the NPK fertilizer input, increased organic fertilizer could improve fertilizer utilization ratio.(5) Controlled release urea with recommended P K fertilizer increased the AN, AvP, AvK content of soil by 14.38%, 6.49%, 13.57% than the common urea with recommended P K fertilizer; controlled release urea 20% reduction had no significant difference on soil fertility, but could save fertilizer input, and reduced the pollution of water environment.So from increasing the rice biomass, promoting the yield and soil nutrient’s perspective, controlled release urea with recommend P K fertilizer was the optimal fertilization model; From reducing fertilizer cost, raising the fertilizer utilization ratio and controlling non-point source pollution perspective, reduce 20% controlled release urea with recommended P K fertilizer was the optimal fertilization model; In addition, increased organic fertilizer should be paired attention to.