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滴灌水肥一体化下施氮量对小麦氮素吸收及土壤硝态氮含量的影响 总被引:6,自引:0,他引:6
为探明华北地区山前平原水肥一体化条件下小麦合理的氮肥运筹。于2013-2015年2个小麦生长季,设置4个滴灌施氮量(N0-不施氮、N1-120 kg/hm~2、N2-240 kg/hm~2、N3-360 kg/hm~2)处理,研究滴灌水肥一体化下施氮量对小麦氮素吸收积累和土壤硝态氮含量的影响。结果表明:施氮量N1、N2和N3处理的小麦干质量及产量较处理N0显著增加,N1、N2和N3处理间无显著差异;施氮量对小麦茎秆的氮含量影响较大,但对籽粒氮含量的影响差异不显著;处理N3的小麦总吸氮量分别显著高于处理N0、N1和N2,但处理N1和N2之间无显著差异;氮肥收获指数以N2处理最高,氮肥当季回收利用率、氮肥农学效率、氮肥生产效率和氮肥利用效率均表现出随施氮量增加而降低的趋势;施氮量超过240 kg/hm~2,土壤硝态氮含量增加,且随种植年限的延长更加明显。采用一元二次方程拟合,获得小麦最高产量的施氮量为238.46~250.78 kg/hm~2,经济施氮量为174.28~207.18 kg/hm~2。综合考虑经济效益和生态效益,该条件下小麦滴灌经济施氮量以174~207 kg/hm~2为宜。 相似文献
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应用同位素32P标记肥料和放射性同位素自显影技术,在网室利用平面根槽和盆栽试验通过滴灌随水施肥的方法,研究了滴灌专用肥(新疆农垦科学院专利产品)和磷酸二铵(美国进口)2种肥料中的磷在土壤中的移动和棉株对磷肥的利用率.试验结果表明:①棉株对滴灌专用肥中磷的利用率为21.05%,磷酸二铵为16.88%.滴灌专用肥比磷酸二铵的利用率高出4.62%.②放射性自显影表明磷酸二铵中的磷在土壤中的最大垂直移动距离为6.2 cm,扩散面积为清水对照的1.85倍;滴灌专用肥中的磷在土壤中的最大垂直移动距离为7.5 cm,扩散面积为清水对照的2.21倍.肥料随水滴施,提高了磷素在土壤中的运移能力. 相似文献
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水肥一体化技术及其应用 总被引:1,自引:0,他引:1
介绍了水肥一体化技术的概念、发展情况及优势、存在的问题,并综述了目前水肥一体化技术的应用效果,最后指出了水肥一体化技术未来的发展方向。 相似文献
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Evaluation of fertigation scheduling for sugarcane using a vadose zone flow and transport model 总被引:1,自引:0,他引:1
V. Ravikumar G. VijayakumarJ. Šim?nek S. ChellamuthuR. Santhi K. Appavu 《Agricultural Water Management》2011,98(9):1431-1440
Micro-irrigation has become an optimal means for providing water and nutrients to crops. There is an ample space for improving fertilizer use efficiency with micro-irrigation, if the movement and reactions of fertilizers in the soil are well understood. However, the rhizosphere dynamics of nutrients is very complex, depending on many factors such as soil temperature, pH, water content, and soil and plant characteristics. Many factors cannot be easily accurately quantified. However, using state-of-the-art modelling techniques, useful and reliable information can be derived.An attempt was made to evaluate the reactive transport of urea in the root zone of a sugarcane crop under drip irrigation, and to quantify the fluxes of urea, ammonium, and nitrate into the crop roots, volatilization fluxes, and deep drainage using a numerical model. This quantification helped in designing an optimal fertigation schedule. Various parameters used in the model were taken from either the literature or the field study. A typical scenario, based on the recommended total quantity of urea for sugar cane crop under drip irrigation in India, was tested using HYDRUS-2D. The total amount of urea was divided into fortnightly doses, depending on the stage of crop growth. For this scenario, the modelled crop uptake was found to be 30% higher than the crop demand. Consequently, an optimal fertigation schedule was developed that reduced the use of urea by 30% while at the same time providing enough N for its assimilation at all stages of crop growth. This type of modelling study should be used before planning field experiments for designing optimal fertigation schedules. 相似文献
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滴灌条件下广西香蕉氮磷钾吸收与分配特性研究 总被引:3,自引:0,他引:3
采用大田试验,研究滴灌条件下威廉斯B6香蕉氮磷钾吸收与分配特性,为该品种香蕉的科学施肥提供理论依据。在香蕉定植后30、60、105、135、165、195和255 d采集样品,分析不同生育期各部位氮磷钾含量。威廉斯B6干物质累积量为19 912.5 kg/hm~2。氮和磷养分吸收量分别为261.8、32.4 kg/hm~2。从定植到定植后195 d,氮磷的累积速率呈上升趋势,定植后195~255 d累积速率开始下降;而钾的吸收量为758.5 kg/hm~2,钾的累积速率在定植后165 d开始下降。从定植到定植后165 d,养分主要分布在叶片、假茎和球茎;定植后195~255 d,养分主要分布在叶片、假茎和果实。收获期,果实中氮磷钾含量占植株氮磷钾吸收量的29.9%、26.5%和12.7%。广西滴灌条件下,新植威廉斯B6香蕉每公顷需要吸收N 261.8 kg、P_2O_532.4 kg、K_2O 758.5 kg。 相似文献
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常规施肥和滴灌施肥对苹果园土壤硝态氮分布的影响 总被引:1,自引:0,他引:1
在大田条件下,通过常规施肥和滴灌施肥处理,研究了其对苹果园土壤硝态氮年周期变化及不同土壤层次分布的影响。结果表明:常规施肥和滴灌施肥处理,0—20、20—40cm土层硝态氮分布在不同物候期的变化趋势一致,均呈双峰趋势,以新梢旺长期和果实膨大期为最高;60—80、80—100cm土层硝态氮分布在不同物候期的变化趋势也一致,均变化较为平缓;而40—60cm土层硝态氮分布在苹果不同物候期差异显著,滴灌处理明显高于常规处理。 相似文献
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