关键词: 硒, 硒, 有效硒, 土壤, 植物

Abstract: To analyze the change and characteristics of precipitation and its impact on rice growth and provide a basis for disaster prevention and mitigation, based on the data of precipitation, development period, yield and flood disaster of meteorological observation stations in main rice producing areas of Heilongjiang Province, the authors studied the variation characteristics of precipitation, storm rainfall and rainstorm days in summer and key growing periods. The authors also analyzed the distribution of floods and waterlogging disasters and the effect of precipitation on rice yield. The results showed that the precipitation from June to August of 1971- 2016 showed a decreasing tendency in the west and east and increase in the middle. The number of rainstorm days in the midwest was more than that in the east and the storm rainfall increased. The average storm rainfall was 76.2 mm in rice critical period with a small upward trend. From 1984 to 2010, the flood was more in the northwest, southeast and middle, and less in the southwest and northeast, the trend was a year by year increase and mainly in summer. The precipitation that restricted rice growth and yield formation varied from place to place. It was mainly in the late July in the north, in late July and late September in the west, in late May, late June and mid- September in the south. The precipitation in the middle and eastern rice areas was more complex and went through almost the entire growing season.