水旱轮作条件下畜禽有机肥氮素矿化特征

为探究水旱轮作条件下不同畜禽有机肥氮素矿化特征，试验设置空白、羊粪、牛粪、鸡粪和猪粪共5个处理，采用田间原位培养法监测了不同有机肥施用后300 d内铵态氮和硝态氮的矿化规律。结果表明：有机肥矿化过程中矿质氮主要为铵态氮，而硝态氮含量很低；不同有机肥处理的铵态氮含量总体呈先上升后逐渐稳定的变化趋势，鸡粪处理的铵态氮含量显著高于其他有机肥处理；不同有机肥处理的硝态氮含量呈波动下降趋势，硝态氮含量在前30 d迅速下降，不同有机肥处理间硝态氮含量差异随时间延长逐渐减小；雨季淹水条件促进有机肥矿化作用，但抑制了硝化作用发生，各有机肥处理的净氮矿化速率在雨季淹水条件培养下较高，旱季好气条件下有机肥矿化速率平稳，无明显上升或下降，各有机肥处理的净氮矿化速率较低；各有机肥处理的净氮矿化速率在培养前期较高，集中在前60 d，不同处理间差异显著，其中鸡粪和牛粪处理显著高于其他处理，培养后期各处理的净氮矿化速率较低且稳定，不同处理间差异较小。经过300 d培养，鸡粪、牛粪、羊粪和猪粪处理的氮素累积矿化量分别为32.99、17.60、13.90、12.83 mg·kg^-1，总体来看各处理氮素矿化效果表现为鸡粪 > 牛粪 > 羊粪 > 猪粪。

The nitrogen mineralization characteristics of organic fertilizer for livestock and poultry under paddy-upland rotation

The objective of this study was to explore the nitrogen mineralization characteristics of different organic fertilizers for livestock and poultry and provide a basis for scientific fertilization under the paddy and dry rotation mode. The experiment included five treatments:blank, sheep manure, cow manure, chicken manure, and pig manure. The field in situ cultivation method was used to monitor the ammonium nitrogen and nitrate within 300 days after application of organic fertilizers. The results showed that the mineral nitrogen of organic fertilizer was mainly ammonium nitrogen, and the nitrate nitrogen content was very low. The ammonium nitrogen content of different organic fertilizer treatments increased first and then gradually stabilized. The ammonium nitrogen content of the chicken manure treatment was significant and higher than the other organic fertilizer treatments. The nitrate nitrogen content of the different organic fertilizer treatments fluctuated and declined rapidly in the first 30 days. The differences in the nitrate nitrogen content between the different organic fertilizer treatments gradually decreased with time. Flooded conditions promote the mineralization of organic fertilizers; however, it inhibits their nitrification. The net nitrogen mineralization rate of each organic fertilizer treatment was higher under the flooded conditions during the rainy season, whereas it was stable under the aerobic conditions during the dry season. There was no significant increase or decrease; however, the net nitrogen mineralization rate of each organic fertilizer treatment was low. The net nitrogen mineralization rate of each organic fertilizer treatment was higher during the early cultivation stage, concentrated in the first 60 days, and the difference between different treatments was significant. The treatment of chicken manure and cow manure was significantly higher than that of the other treatments. The net nitrogen mineralization rate of each treatment during the later culture period was low and stable, and the difference between the different treatments was small. After 300 d of culture, the cumulative nitrogen mineralization amounts of the chicken manure, cow manure, sheep manure, and pig manure treatments were 32.99, 17.60, 13.90, 12.83 mg·kg^-1, respectively. Therefore, the nitrogen mineralization effect of each treatment was in the order of chicken manure > cow manure > sheep manure > pig manure.