How to apply nitrogen fertilizer in fish farming rice fields
Raising fish in rice fields at the same time is called "fish farming in rice fields". Reasonable application of nitrogen fertilizer in fish farming rice fields will have a good impact not only on the growth of rice, but also on fish. When applying nitrogen fertilizer to fish farming rice fields, it is crucial to choose the appropriate nitrogen fertilizer variety. The ammonium bicarbonate in chemical fertilizers is poisonous to fish to a certain extent. It is best to use it as base fertilizer, and then release fish fingerlings one week after application. For nitrogen fertilizer, urea and ammonium sulfate should generally be used as top dressing. 7.5 to 10 kilograms of urea per 667 m2 should be used, and ammonium sulfate should be doubled. If ammonium bicarbonate is needed, it should be applied in small amounts and multiple times. When topdressing, you should first put shallow field water to drive the fish into the fish ditch or pit, and then deepen the field water after applying fertilizer. This will have no impact on the fish. In addition, the top dressing of livestock manure can be used as fish bait and provide a good source of fertilizer for rice. It can be said that it kills two birds with one stone.