| 摘要: |
| 【目的】探索赣抚平原灌区不同水文年型适宜的水稻水肥综合调控模式，为灌区水稻水肥管理提供决策依据。【方法】基于江西省灌溉试验中心站2012—2013年晚稻试验资料对ORYZA_V3模型进行了率定与验证，并以率定后的模型模拟分析了不同水文年组及水肥模式下晚稻灌溉定额、产量、氮肥利用率等指标。【结果】降低灌前水分下限能降低腾发量与灌溉定额。耕作层灌前土壤含水率大于饱和含水率的70%~75%时，降低灌前水分下限均能提高晚稻的产量与氮肥利用率。耕作层灌前土壤含水率低于饱和含水率的60%~65%时，晚稻产量、氮肥利用率均有所下降。施氮肥量增加会降低氮肥利用率，施氮肥次数增加能提高氮肥利用率，二者增加均能增加晚稻产量，但会导致晚稻耐旱能力降低。从节水、增产、增效的角度，推荐试验区采用的水肥综合调控模式：氮肥量135 kg/hm2，分3次施用（基肥∶分蘖肥∶穗肥为5∶3∶2），丰水年采用重旱节水灌溉模式（耕作层灌前土壤含水率下限占饱和含水率的60%~65%），平、枯水年采用中旱节水灌溉模式（耕作层灌前土壤含水率下限占饱和含水率的70%~75%）。【结论】与传统水肥模式相比，所推荐水肥模式在丰、平、枯水年能分别节水41.4%、30.0%、21.9%，增产7.5%、5.4%、3.4%，提高氮肥利用率57.3%、51.2%、44.9%，节省氮肥25%。 |
| 关键词: 水稻； 模型； 水肥； 氮肥利用率； 灌区 |
| DOI：doi：10.13522/j.cnki.ggps.20180511 |
| 分类号: |
| 基金项目: |
|
| Using the ORYZA_V3 Model to Help Improve Water andFertilizer Management of Rice Field |
|
YU Qianan, LI Yalong, LIU Luguang, CUI Yuanlai, CHEN Yang, HAN Huanhao
|
|
1.State Key Laboratory of Water Resources and Hydropower Engineering Science,Wuhan Univercity, Wuhan 430072, China; 2. Changjiang River Scientific Research Institute of Changjiang Water Resources Commission, Wuhan 430010, China; 3. Hubei Water Resources Reasearch Institute, Wuhan 430070, China
|
| Abstract: |
| 【Objective】 Improving resource use efficiency is critical to sustaining agricultural production and this paper is to study the feasibility of using the ORYZA_V3 model to help improve water and fertilizer management in irrigated rice field. 【Method】 The study focused on Jiangi Irrigation Experimental Station. We first calibrated the ORYZA_V3 model against data collected in 2012—2013 from the station, and then used it to analyze the irrigation amount, yield, nitrogen use efficiency of the later-season rice under different hydrological years, as well as water and fertilizer management. 【Result】 Reducing the critical low soil moisture for irrigation can reduce evapotranspiration and thus irrigation amount. Particularly, setting the low soil moisture in the plowed layer for irrigation at 70%~75% of saturated water content prior to irrigation increased the yield and nitrogen use efficiency of the rice. In contrast, setting the low soil moisture in the plowed later for irrigation lower than 60%~65% of the saturated water content reduced both yield and nitrogen use efficiency. Increasing nitrogen fertilizer application reduced its use efficiency, whereas increasing fertilization frequency facilitated nitrogen use efficiency. Increasing nitrogen amount and fertilization frequency increased the yield but at expense of reducing drought-tolerance of the plant. For balancing water saving, yield and nitrogen use efficiency, keeping nitrogen application at 135 kg/hm2 and applying it in three times (base fertilization, tiller fertilization and panicle fertilization at ratio of 5∶3∶2) appeared to give the best result. In wet years, the critical soil moisture in the plowed layer for irrigation can be set at 60%~65% of saturated water content, while in normal and dry year it can be increased to 70%~75% of the saturated water content. 【Conclusion】Compared with traditional water and fertilizer application, using the above optimized fertigation can save water by 41.4%, 30.0% and 21.9%, increase yield by 7.5%, 5.4%, 3.4%, and nitrogen use efficiency by 57.3%, 51.2%, 44.9% in wet, normal and dry year, respectively. On average, it can overall save nitrogen fertilizer by 25%. |
| Key words: lowland rice; model; water and fertilizer; utilization rate of nitrogen; irrigated area |
