Nutrient Characteristics Of Nitrogen, Phosphorus And Potassium In Arable Layer Of Liaoning Coastal Saline Paddy Soil With Different Yield Levels

It has been investigated that soil NPK nutrient status and the characteristics of their forms in the arable layer soil through soil survey, testing and recommended fertilization field experiment from the inshore saline paddy soil in area with Panjin city, Liaoning province. Main results and conclusions are as follows:1. The soil total nitrogen, amino nitrogen, amino sugar nitrogen, acid insoluble nitrogen content within the soil organic nitrogen components in Liaoning coastal saline paddy soil with high-yielding rice, were no significant differences compared with the those of low-yielding paddy soil, respectively.2. Acid hydrolysis of total nitrogen, ammonia nitrogen and unknown acid hydrolysis nitrogen contents among the organic nitrogen components in Liaoning coastal saline soils topsoil with the high-yielding rice were higher than those of low-yielding paddy soil, respectively.3. In Liaoning coastal saline topsoil soils with high-yielding rice, the organic nitrogen components consist of the respective proportions of 8%amino nitrogen,3% amino sugar nitrogen,17% ammonia nitrogen,48% unknown acid hydrolysis nitrogen and 24%acid insoluble nitrogen; In low-yield paddy tilth soil, organic nitrogen components consist of the respective proportions of 9%amino nitrogen,2% amino sugar nitrogen,13%ammonia nitrogen,41% nitrogen unknown acid hydrolysis and 35%acid insoluble nitrogen.4.The total phosphorus, and reactive organic phosphorus, moderate active organic phosphorus, higher stable organic phosphorus within organic phosphorus forms, and Caio-P, Al-P, O-P content within inorganic phosphorus components, in Liaoning coastal saline soils topsoil with the high-yielding rice have no significant difference compared with the those of low-yielding paddy soil, respectively.5. Soil available phosphorus, and Ca2-P, Cas-P, Fe-P form in the inorganic phosphorus components, and moderate stable organic phosphorus fraction in the topsoil were significantly higher than those of low-yielding paddy soil, respectively.6. In coastal saline topsoil soil with high-yielding rice, the organic phosphorus component proportion consists of 3% available organic phosphorus,77% moderate active organic phosphorus,13% moderate stable organic phosphorus,7% higher stable organic phosphorus; the inorganic phosphorus component proportion consists of 2% Ca2-P,4% Ca8-P, 3% Ca10-P,7% Al-P,24% Fe-P and 60% O-P; In low-yield paddy topsoil soil, the organic phosphorus component proportion consists of 4% available organic phosphorus,79% moderate active organic phosphorus,9% moderate stable organic phosphorus,8% higher stable organic phosphorus; the inorganic phosphorus component proportion consists of 2% Ca2-P,3% Ca8-P,3% Ca10-P,7% Al-P,15% Fe-P and 70% O-P7. The soil total potassium, available potassium, slowly available potassium content in Liaoning coastal saline paddy soil with high-yielding rice, were no significant differences compared with the those of low-yielding paddy soil, respectively.8. In Liaoning coastal saline soil tilth with high-yielding rice, the slowly available potassium and available potassium content accounts for 6.95% and 1.25% of total potassium content, respectively; In Liaoning coastal saline soil tilth with low-yielding rice, the slowly available potassium and available potassium content accounts for 6.51% and 0.87% of total potassium content, respectively.The research results will be helpful to improve the theoretical basis and data support for recommendation fertilization and rational utilization of paddy soil.