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Study on the Utilization of Water and Nitrogen and the N-Fertilizer Balance under Water Saving Irrigation

Author: LiuZuo
Tutor: LvGuoAn
School: Huazhong Agricultural University
Course: Soil
Keywords: Water-saving irrigation Rice Nitrogen Fertilizer nitrogen balance Nitrogen use efficiency Water productivity 13N isotope
CLC: S511
Type: Master's thesis
Year: 2005
Downloads: 408
Quote: 1
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Abstract

Irrigation experiment station in Hubei Zhanghe large Lysimeter May 2003-September, on the basis of domestic and foreign rice water-saving irrigation existing achievements, the long-term flooding irrigation (W0) and water-saving irrigation (W1) two kinds of irrigation 0kgN/hm ^{2 (N0), 120kgN/hm ^{2 (N1) and 180kgN/hm ^{2 (N2) three kinds nitrogen levels, as well as three nitrogen fertilization methods - F1: basal fertilizer, 30% tillering 30% 30% jointing fertilizer Paul fertilizers 10%, the F2: basal fertilizer, 50% jointing fertilizer by 50%, F3: basic fertilizer 50% 30% jointing fertilizer tillering 20% of the combined ^{15 N tracer method, nitrogen nutrition and nitrogen leaching medium rice (hybrid), rice paddy fertilizer nitrogen balance, and water use efficiency. The main results are as follows: 1, water-saving irrigation rice on nitrogen absorption and utilization of significant change. Performance under the conditions of water-saving irrigation, the rice root, stem, leaf nitrogen content in the vegetative growth stage than flooding irrigation of the reproductive growth stage is not very different to deal with the flooding irrigation. From the cumulative view of nitrogen, water-saving irrigation rice roots and rice (including panicle and grain) the cumulative amount higher than the flooding irrigation, and the leaves and stems are lower than flooding irrigation. Water-saving irrigation favor on nitrogen absorption and utilization of rice vegetative stage and reproductive growth stage nutrient transfer to yield organs. 2, leakage of nitrogen content in water and fertilization was positively correlated with nitrogen application volume higher its leaching nitrogen. The total amount of nitrogen leaching flooding irrigation treatments were significantly higher than the water-saving irrigation. The whole growth period different fertilization between nitrogen leaching at least F1 treatment, followed by F3 deal F2 processing nitrogen leaching. Directly measured by the nitrogen use efficiency, F1 and F2 processing performance is higher than the flooding irrigation water-saving irrigation, and F3 processing performance is the flooding irrigation higher than the water-saving irrigation. Isotope method measured nitrogen use efficiency is higher than that of water-saving irrigation the flooding irrigation of, and with the amount of fertilizer to increase nitrogen use efficiency of a downward trend. 4, change the biological characteristics of different water and fertilizer conditions, thus affecting the plant configuration and production. Water-saving irrigation to some extent inhibited ineffective tillers and leaf area index maintained a relatively modest level of the whole growth period, the individual growth of rice plants better than flooding irrigation has laid a good foundation for the formation of high-yielding. 5, the same kind of fertilizer levels, F1 and F2 under production performance is higher than that of water-saving irrigation flooding irrigation the F3 processing performance is the flooding irrigation higher than the water-saving irrigation. Recommended the local adoption W1N2F1 water and fertilizer management mode. 6, water-saving irrigation can significantly increase the productivity of water. Shallow water layer of water-saving irrigation rice fields, part-time field surface water layer, reducing the paddy moisture leakage, evaporation and transpiration, thereby improving water productivity. 7 of this study the proportion of paddy fields seepage water and residual fertilizer nitrogen in the soil, the establishment of a rice paddy fertilizer nitrogen balance equation, initially clear nitrogen in crop uptake, soil residual leaching lost and gaseous nitrogen. Nitrogen fertilizer applied into paddy fields, absorbed by crops is less than 2/5, the residue in the soil, about 1/4 Shuilin loss of fertilizer nitrogen proportion is less than 0.5% by leakage into gaseous nitrogen losses the largest proportion of about 2/5-1/2.}}}}

Study on the Utilization of Water and Nitrogen and the N-Fertilizer Balance under Water Saving Irrigation

Abstract

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