灌溉量与减氮配施有机肥模式对温室黄瓜及土壤的影响.

Irrigation and fertilization patterns can be greatly conducive to the efficient management of water and fertilizer in facility agriculture. It is very necessary for the protection of the soil environment, the high quality and yield of crops. In this study, a systematic investigation was implemented to clarify the effects of different irrigation amounts and fertilization patterns on soil physicochemical properties, crop yield, quality, water use efficiency (WUE), and nitrogen partial productivity (NPP). A series of experiments were conducted under different rates of nitrogen reduction (N1: 275 kg/hm2, N2: 220 kg/hm2, N3: 165 kg/hm2 ) combined with organic fertilizer (O1: 12 t/hm2, O2: 8 t/hm2 ) under full (W1) and deficit (W2) irrigation for greenhouse cucumber. A systematic analysis was also made to determine the effects of different irrigation amounts and nitrogen reduction that combined with organic fertilizers on the soil physicochemical properties (soil bulk density, soil porosity, water-stable aggregates content, three-phase ratio, soil nitrate nitrogen content), cucumber quality (soluble solids, soluble glucose, vitamin C), yield, WUE, and NPP. The experimental results showed that both nitrogen reduction and organic fertilizer application effectively improved the soil structure and environment. The soil bulk density decreased by an average of 5.8%, whereas, the soil porosity increased by an average of 7.7% in the O1N3 treatment, compared with the rest under the same irrigation condition. At the same time, the soil gas and liquid volume fraction increased significantly in the O1N3 treatment. The three-phase ratio was optimized as well. The content of large-size water-stable aggregates increased by an average of 25.4%, whereas, the nitrate nitrogen content in the 0-30 cm soil layer decreased by 21.8% on average. The nitrate nitrogen content in the 0-30 cm soil layer decreased with the increase of nitrogen reduction, but increased with the increase of organic fertilizer application. The nitrate nitrogen content tended to decrease and then increase with the soil depth at the W1 level, while the nitrate nitrogen content decreased constantly at the W2 level. There was no significant effect of O2N2 treatment on the nitrate nitrogen content under the same irrigation condition. Cucumber WUE increased with the increase of irrigation amount, nitrogen fertilizer, and organic fertilizer application. By contrast, the cucumber NPP decreased with the increase of nitrogen application, but increased with the increase of irrigation amounts and organic fertilizer application. Meanwhile, the organic fertilizer application effectively improved the greenhouse cucumber WUE and NPP under the same irrigation and nitrogen fertilizer conditions. Specifically, cucumber WUE and NPP of O1 level increased by 14.5% and 15.7% on average, respectively, compared with O2 level. A comprehensive analysis was then performed on the cucumber yield and quality indicators under different treatments. Both deficit irrigation and excessive nitrogen reduction seriously reduced the cucumber yield and quality, while the W1O2N2 treatment performed the best. There was no significant difference in the content of soluble glucose, soluble solids, vitamin C, and yield of cucumber, compared with the W1O1N1 treatment (P>0.05). The crop yield and quality can be expected to effectively guarantee with the better soil environment and the less fertilizer application, particularly for the economic benefits of production. The finding can also provide an important reference for the scientific water and fertilizer management in the green and efficient crop production of facility agriculture. [ABSTRACT FROM AUTHOR]