Dissertation > Excellent graduate degree dissertation topics show

Studies on Nutrient Distributing Principle and Environmental Effect Under Organic Vegetables Planting System in Protected Field

Author: ZhangJie
Tutor: LiuChunSheng
School: Shandong Agricultural University
Course: Plant Nutrition
Keywords: Organic vegetables Nitrate Nitrogen Phosphorus Leaching
CLC: S626
Type: Master's thesis
Year: 2010
Downloads: 92
Quote: 1
Read: Download Dissertation

Abstract

Organic vegetable industry has developed rapidly in our country, in a highly intensive organic vegetable production areas (such as Shandong, Beijing and other regions), due to planting conventional fertilizer management experience alone engaged in the cultivation of organic vegetables, lack of water and fertilizer in organic farming, resource management theory and the test data, the cultivation of organic vegetables is facing a series of problems. Under organic farming conditions, this study investigated the two irrigation treatments (W1: conventional irrigation; W2: reduction of irrigation) as well as three fertilization treatments (N1: conventional fertilization; N2: reduction fertilization; N3: control treatment) on organic vegetable production, quality, changes in soil nutrients N, P leaching of nutrients and other issues, its findings are as follows: the amount of organic fertilizer in organic vegetable cultivation reduced to 2/3 of the amount of conventional fertilization, irrigation reduced to conventional irrigation 80% of the time, except the first crop of vegetables, reduce remaining Liangcha vegetable production. Simultaneously the conventional fertilization treatments radish nitrate content excessive risk, fertilizer, the nitrate content of organic vegetables in a greater impact than irrigation amount. When the amount of organic fertilizer is reduced to 2/3 of the amount of conventional fertilizer, the nitrate content of radish reduction fertilization treatments than conventional fertilization treatments reduced 27.1%; When irrigation is reduced to 80% of conventional irrigation less the amount of irrigation treatments radish nitrate content decreased 6.3% compared with conventional irrigation treatments. Conventional fertilization led to organic vegetables to 0-90 cm soil inorganic nitrogen gradually accumulated. Soil inorganic nitrogen content of conventional irrigation and reduction of irrigation, conventional fertilization treatments, respectively, up to 395.99 kg / ha, 366.58 kg / ha; reduction fertilization treatments soil inorganic nitrogen content were 298.85 kg / ha, 294.25 kg / ha, significantly lower soil inorganic nitrogen content. In this study of organic fertilizer nitrogen as recommended objects, while organic fertilizer N, P, K nutrients exist imbalance, which leads to the accumulation of the 0-30 cm soil layer of soil phosphorus, which conventional irrigation and reduction irrigation, the conventional fertilization treatments available phosphorus content were as high as 237.75mg/kg 248.34 mg / kg. After the third harvest vegetables, fertilization treatments of soil organic matter, total nitrogen, total phosphorus content were improved to some extent, this also shows that organic fertilizer with soil fertility. Organic vegetable cumulative amount of eluent and irrigation amount and fertilization. By irrigation control can significantly reduce the the third harvest the eluent cumulative amount of dishes, when irrigation reduced to 80% of the conventional irrigation eluent cumulative amount of reduction of irrigation treatment decreased 31.4% compared with conventional irrigation treatments; When organic fertilizer application rate reduced to 2/3 of the amount of conventional fertilization reduction fertilization treatments eluent cumulative decrease of 22.2% compared with conventional fertilization treatments. Irrigation amount and fertilization amount of the third harvest vegetables N, P cumulative leaching amount is closely related to control irrigation and fertilizer volume of can reduce N, P cumulative leaching amount. When irrigation is reduced to 80% of conventional irrigation, reduction irrigation treatments of N, P cumulative leaching amount compared with conventional irrigation treatments were reduced by 47.0%, 65.4%; reduced to the amount of conventional fertilization when the amount of organic fertilizer 2/3, the reduction fertilization treatments of N, P cumulative leaching amount compared with conventional fertilizer treatments were reduced by 29.5%, 52.5%. Nitrogen, Phosphorus, and Potassium surplus conventional fertilization treatments were higher than the reduction fertilization treatments. Conventional irrigation and reduction of irrigation, the conventional fertilization treatments Phosphorus surplus as high as 4398.6 kg / ha, 4387.75 kg / ha. Excessive inputs of phosphorus in organic manure-based nitrogen fertilizer recommendation is the main reason for the accumulation of soil phosphorus. The nutrient utilization Potassium highest, followed by nitrogen and phosphorus in the lowest. Irrigation water use efficiency and reduction of irrigation treatment was significantly higher than that of conventional irrigation treatments.

Related Dissertations

CLC: > Agricultural Sciences > Gardening > Horticultural ( protected cultivation ) > Vegetable Horticultural
© 2012 www.DissertationTopic.Net Mobile