基于RCSODS的东南沿海水稻施肥量决策

应用RCSODS模型,根据东南沿海福建稻区8个代表县(市)的土壤理化性状和水稻生长期气温资料,模拟计算了各地稻田的土壤供肥量;结合主栽品种的目标产量和肥料利用率,模拟计算了早晚稻的合理施肥量。结果表明:在研究区域土壤有机质含量与全氮含量适中,磷、钾含量普遍偏低以及土壤偏酸性的情况下,要实现水稻现有水平的目标产量,早稻需施纯氮56.98~231.85kg.hm-2,其中大部分稻田需施133.9~231.85kg.hm-2;需施磷肥(P2O5)73.28~173.57kg.hm-2,其中缺磷稻田需施132.69~173.57kg.hm-2;需施钾肥(K2O)15.41~257.63kg.hm-2。晚稻需施纯氮64.63~237.93kg.hm-2,大部分稻田需施纯氮167.77~237.93kg.hm-2;需施磷肥(P2O5)88.76~176.72kg.hm-2,其中缺磷的稻田应施磷肥(P2O5)155.38~176.72kg.hm-2;需施钾肥(K2O)50.41~315.96kg.hm-2。比较福建稻区的实际施肥量与模拟施肥量,可以看出:目前氮肥施用量总体上比较适宜,而磷肥和钾肥施用量则明显不足。

Decision Making Supporting System on Rate of Fertilization of Rice in Southeast Coast Areas of Fujiang Province Based on RCSODS

Based on the data of soil physical-chemical characteristics and the temperature during rice growing period in eight representative counties and cities in the southeast coast areas of Fujian Province,the soil capacities of fertilizer supply both for early and late rice were simulated,by using the RCSODS model.The rational rates of fertilizer application were also simulated,according to the local yield targets of the main rice varieties as well as the fertilizer use efficiencies.The results showed that the organic matter content and total amount of nitrogen in rice fields were medium,while the available phosphorus(P) and potassium(K) were deficient in general,as the most of soils in Fujian Province are acidic.In order to reach the target yields at the present level,for the early rice it needs to apply 56.98-231.85 kg N/ha and 73.28-173.57 kg P2O5/ha and 15.41-257.63 kg K2O/ha.For the late rice the fertilization rates were as follows: 64.63-237.93 kg N/ha,88.76-176.72 kg P2O5/ha and 50.41-315.96 kg K2O/ha.In comparison of the actual fertilization rates with the simulated rates,it could be concluded that the actual rates of nitrogen fertilizer application at present in Fujian Province was appropriate,while the rates of phosphate and potassium fertilizers were obviously insufficient.