| As a new agricultural irrigation water way, sea-ice water has great potential because of the richness of water resources and agricultural irrigation water stress. This paper based on previous studies. A field experiment was conducted on the Zhongjie Farm of Hebei province to research the temporal and spatial change of soil moisture and soil salinity by different irrigation condition and we hope we can get the sea-ice water safe efficient utilization index system and matching technology by considering the situation of soil salt accumulation, yield and quality of cotton.1. Soil moisture, salinity and pH values were conform to season variation on without irrigation in 2009. Soil salinity and soil moisture were basic inversely proportional, with soil moisture changes. A cotton-growing season, the soil salinity decreased, pH values increased significantly. Seasonal change of soil in 60-100cm was influenced by the water table.2. Before sowing of cotton irrigated using sea-ice water could significantly increase the soil water content. Using 3g/L Sea-ice water before sowing of cotton irrigation can significantly increase soil moisture and the bigger of irrigation, the higher the water content of the soil. It can improve soil moisture and is conducive to leaching the soil surface salinity, also make a good conditions for cotton emergence.2nd irrigation (during the blooming period) has entered the rainy season, although it can increase soil moisture of the 0-60cm layer, but the increase smaller. The effect of 1st irrigation is more effect than 2nd irrigation.So, according to test results, I suggested that the 2nd irrigation advance to the seedling or bud.3. Different salinity of sea-ice water on the soil moisture content were different. Maximum water content of soil irrigation was 20-40cm by Salinity of 3%o and 5%o of the sea-ice water, but maximum water content of irrigated soil was 40-60cm by salinity of 7%o and 9‰Of the sea-ice water. In the same irrigation frequency, the higher the salinity of irrigation water, the more the infiltration of soil moisture. It can increase lower soil water content.3 times irrigation of ice-sea water showed that:1st and 2nd irrigation could increase 20-60cm of soil water content; the 3rd irrigation before Boll opening can increase 40-60cm of soil water content, but all kinds of treatments were no significant difference because of the impact of rain.4.525 m3/hm2 irrigation of 3‰salinity of the sea-ice water in 0-60cm of soil was best. Different irrigation of sea-ice water and soil desalination was a significant positive correlation. 525m3/hm2 irrigation of 3‰salinity of the sea-ice water was best. In 0-60cm or so,3‰of sea-ice water irrigation can effect on the leaching of soil, and the closer to the surface, the more complete leaching of soil salinity. It can consider that irrigation of sea-ice water can increase the leaching of soil and soil desalinization.5. Soil salt in 20-60cm accumulation with salinity of the sea-ice water and irrigation frequency increases. When salinity of the sea-ice water≤5‰, soil salt was leached significantly and reduced the rate of salt accumulation. Many year ago, concentration and frequent of irrigation of the Sea-ice water experiment showed that:if soil salt in 20-60cm accumulation with increasing salinity of the sea-ice water; if the same salinity of irrigation water, soil salt content was increased with the frequent of irrigation increased; the higher salinity of irrigation water, gap of soil salt was more obvious differences with different irrigation times. Comprehensive analysis, when the salinity of irrigation water< 5%o, leaching of soil salt was increased and soil salt accumulation rate was reduced.6.3g/L of sea-ice water irrigation can promote desalination of soil, improving the ratio of salt in the soil, reduce Na+and Cl- content of soil. Compared pre-and post-harvest cultivation, 3g/L of sea-ice water can removal the Na+, SO42- and Cl- of soil, increasing the content of K+, Mg2+ and Ca2+, and the larger of irrigation, the larger the changing value of deep soil. Leaching effects of NO3- ions were most significant. Content of it was minimal in the 20-100cm of soil after harvest.7. Cotton seedling emergence was increased significantly with the amount of sea-ice water. Test area was arid in spring, salt go back to the ground, and cotton seedling grow up serious difficulties. The results show that the emergence of cotton seedling and the soil salt content in 0-20cm were a significant negative correlation (P<0.01), irrigation of the sea-ice water can significantly increase cotton seedling emergence, and irrigated with well water was not significant.525m3/hm2 in irrigation treatment was the highest rate of emergence.8. Biological characteristics of cotton in3‰of sea-ice water irrigation volume of 525 m3/hm2with two times were best. cotton plant height, number of fruit branches, the number of bolls and single bolls weight were increased with volume of irrigation increased, and achieve the maximum value when the total amount of irrigation was 525 m3/hm2 (irrigation 2 times). Ground dry weight and seed cotton yield have the same rules were 11575.1 kg/hm2 and 3265.78 kg/ hm2 as irrigation volume of 525 m3/hm2, increased 76.90% and 164.36% than CK.9. Different salinity of the sea-ice water had significant effects on cotton yield, while no significant effect on cotton quality. Biological characteristics of cotton were all showed that they were decreased with the increase of salinity of irrigation water. When salinity of the irrigation water>7‰, the larger the amount of irrigation, the worse cotton growing, but production did not show reduced. Production was significantly reduced if irrigation water salinity to 9‰. Compared with the well water,3‰of sea-ice water irrigation can increase the degree of consistency of cotton fiber, yarn spinning, capability and the grade of cotton with the difference significant. The higher sea-ice water concentration and frequency of irrigation will reduce cotton fiber quality, but the difference was not significant.10. Analyzing comprehensive the dynamics of soil salinity and water, combining with the cotton yield and quality, we can get Sea-ice water secure and efficient irrigation index. The best sea-ice water irrigation institution is b-3 (before seedtime and at seedling stage). Flood irrigation amount was 525m3/hm2 each time. It can not only increase production but also improve the quality of cotton. 2nd of irrigation to the seedling and bud should be better. Salinity of irrigation water< 5g/L will only mild accumulate salt of soil, also it need good drainage and farming measures to achieve the purpose of soil improvement and desalination, which can prevent the influence for the soil properties because of accumulation of salt. |
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