Abstract:

To provide a basis for the realization of precision formula fertilization, the migration and distribution of available components of nitrogen, phosphorus and potassium in rice terraces were studied. Ten villagers’ groups with rice terraces in Baishi Village were selected. Each villagers’ group was a sampling area. According to the water flow path, the terraces in each sampling area were divided into six layers. Five soil samples were collected in each layer by serpentine distribution method. The contents of alkali-hydrolyzable nitrogen, available phosphorus and available potassium were measured respectively, and the functional relationship with the terraces was established to study the horizontal migration and distribution. The results showed that the average content of main nutrients in Baishi Village soil were alkali-hydrolyzable nitrogen 103.3±13.67 mg/kg, available phosphorus 42.84±5.42 mg/kg, available potassium 95.25±13.91 mg/kg, and the nutritional grade was above average. Alkali- hydrolyzable nitrogen and available potassium migrated from upper terrace to lower terrace, and there was a significantly exponential regression trend. The average correlation coefficient was 0.9719 and 0.9885 respectively. The nitrogen content in low-lying land was high. The vertical migration of available phosphorus was not obvious, but its content was negatively correlated with the content of alkali-hydrolyzable nitrogen, and the fitting degree was 72.72%. The contents of alkali-hydrolyzable nitrogen and available potassium in rice terraces in Baishi Village migrated from the upper layer to the lower layer with the water flow, and had an obvious exponential regression trend. The migration of available phosphorus was not obvious with the flow, but the distribution was relatively stable and tended to be enriched.

Key words: rice terraces, soil nutrients, migration, distribution, formula fertilization