【作者】 曾燕舞；

【导师】 任华中；

【作者基本信息】 中国农业大学 ， 蔬菜学， 2003， 硕士

【摘要】 针对目前蔬菜生产中水氮投入过大导致了一系列不良影响的实际情况，本试验在前人研究结论的基础上，以露地花椰菜和菠菜为试验材料，研究了五种不同的水氮处理(W1N1，W2N2，W3N3，W3N1和W3N2)对蔬菜产量、品质及土壤水分、氮素的影响，并计算出不同水氮处理条件下土壤90cm土深处的水通量、氮素淋洗量和水分、氮素利用效率，最后采用灰关联法对所有参试水氮处理进行多目标综合评价。主要研究结果如下： 1) W1N1处理花椰菜明显减产外，其他处理产量差异均不显著。 2) 水氮过多或过少会降低蔬菜可溶性固形物和水分含量，并使蔬菜体内酸性物质增加。水分对蔬菜VC、蛋白质和硝酸盐含量的影响较小；水氮互作对蔬菜可溶性糖含量和含酸量存在较大影响；增施氮肥，有利于提高蔬菜蛋白质含量，但同时也增加蔬菜的硝酸盐含量。 3) 蔬菜品质的灰关联分析综合评价结果表明，氮素是影响蔬菜品质的重要因素，氮素过多过少都使蔬菜品质变劣，而适宜的灌溉量有利于提高蔬菜品质。W2N2处理是取得最优蔬菜品质的水肥管理模式。 4) 90cm土层土壤贮水量，90cm土深处的累积水通量和蔬菜耗水量的变化与灌溉、降雨联系密切，一般呈正相关；氮素处理对其影响不明显。水分利用效率与灌溉和降雨总量呈反相关关系，氮肥处理对土壤水分利用效率的影响不明显。 5) 一定水氮供应条件下，露地生产蔬菜地土壤硝态氮有可能淋洗到1.8米土体以下。 6) 氮肥施用量是影响土壤氮素消耗、氮素淋洗以及氮素利用效率的重要因子。施肥量越大，土壤氮素消耗量越大，氮素淋洗越严重，土壤氮素利用效率越低。水分的影响较小，但适量灌溉有利于减轻氮素淋洗，提高氮素利用效率。 7) 在对五种水氮处理(W1N1，W2N2，W3N3，W3N1，W3N2)进行的考虑蔬菜品质的灰关联多目标综合评价中，W3N2处理经济和环境效益最优。更多还原

【Abstract】 In this experiment, the effects of 5 water and nitrogen treatments (W1N1, W2N2, W3N3, W3N1, W3N2) on vegetable yields, quality .water and nitrogen use were studied in cauliflower and spinach grown in open land. The water flux and N leaching in 90cm soil , soil water use efficiency and soil nitrogen use efficiency were calculated. In addition, different treatments were evaluated multi-objectively and comprehensively by Grey Relativity Analysis. The main results are as follows:1. Except W IN 1 treatment of cauliflower got much less yields, the yields of all other treatments had no distinct difference.2. The shortness and excessiveness of water and nitrogenous fertilizer would reduce the content of water and total soluble solid, increase the content of acid within vegetable tissue products. The effects of nitrogenous fertilizer on the change of the content of VC, protein and nitrate in vegetable tissue product were greater than those of water. And increasing the supply of nitrogenous fertilizer would increase the protein and nitrate content of vegetables. Besides these, the soluble sugar and acid content of vegetables were influenced greatly by the interaction between water and nitrogen.3. The results of Grey Relativity Analysis on vegetable quality showed that the nitrogen was the most important affecting factor on quality and the proper irrigation would optimize vegetable quality. Taking into account of quality, W3N2 was the best in all of the 5 irrigation and fertilization treatments.4. The water store, the accumulated water flux of 90cm soil and the water consumption were positively effected mainly by irrigation and precipitation, and soil water use efficiency was correlated with water supply in reverse, while the effects of nitrate treatments were not distinct.5. Under a certain water and nitrate treatments, soil nitrate in open-land vegetable field would move down below 180cm soil.6. Big nitrogen supply would lead to low soil nitrogen consumption, soil nitrogen leaching andsoil nitrogen use efficiency. And nitrogen was the main affecting factor compared to water, but proper irrigation would reduce nitrate leaching and increase soil nitrogen use efficiency.7. Among the five treatments of W1N1, W2N2, W3N1, W3N2 and W3N3, W2N3 had the best economic and environmental benefits based on the results of Grey Relativity Analysis considering vegetable quality.更多还原