| With the increase of the world population and the shortage of water resources, it has become a hot issue at present for all over the world to develop rationally and utilize the Unconventional resources. Drip irrigation under plastic film that the drip is placed under the plastic film, which couples with the drip irrigation technology and the plastic film technology, also is a leap in drip irrigation technology. The emergence of drip irrigation under plastic film has provided new ideas and methods for the development and utilization of rich brackish water and increasing salinized land.This research was based on Xingjian, "Eleventh Five-Year" key scientific and technological issues of major sub-projects, "the key technology of Drip irrigation under plastic film and the development and demonstration of the water-salt regulation and control technology for cutton"and national "Eleventh Five-Year" project to support science and technology sub-topics "the southern edge of Jogger Basin, the rational allocation of water resources and high technology research," as the background. A more comprehensive summary of the research of the water and salt transport and system regime at home and abroad and study the Characteristics of Soil Water and Salt Movement in Brackish Water under Drip Irrigation and the water-salt regulation and control technology1. By the three-dimensional infiltration of brackish water drip irrigation, it was researched that the effects of different degree of mineralization and flow on water-salt distribution characteristics, and soil moisture and salinity characteristics as well as the wetting front in the convergence of overlapping interface. When a certain degree of mineralization is at 0 ~ 15cm layer, the same depth of wet, the emitter flow the greater, the moisture content of soil profiles greater, salinity is relatively smaller; between 15cm layer and the wetting front, the same depth of wetting front, the greater of the emitter flow, the smaller the soil profile water content, salt content is relatively greater. Wetting front of the convergence of soil water content, salinity and depth of moist soil are generally higher than the same distance and depth moisture content, salinity and depth of wetting. The use of brackish water can form a high moisture content and low salinity region near the drip irrigation emitter, which can provide a good crop of salt-water environment.2. Selecting salinized land from the southern edge of Jogger Basin, the water-salt regulation and contro is studiedl in Test pit. The basic principle is: Horizontal direction, the more recent to the drip tipe with the higher moisture content, the lower the salt content; farther away from the drip tipe with lower moisture content, the higher the salt content; vertical direction, the changeable trend of soil moisture is first increased and then decreased. The salt content is first decreased and then increased.3.There are four irrigation quotas(4500,5250,6000 and 6750m~3/hm~2) and one comparing treatments(4500m~3/hm~2). Different irrigation quotas control Different scale of soil moisture, irrigation quota for 5250m~3/hm~2 ranges from 12.7 ~ 15.92% of soil moisture at a critical growing period, which provides a good water environment for cotton. The suitable salt content of the cotton genotypes of Biao za in different development stage is: seedling stage less than 1%; at budding,flower and boll stage in the 1% ~ 1.5% for the normal cotton growth, the yield is higher, growth limited when the soil salinity in the scale of 1.5% ~ 2%, production is relatively low, cotton unable to grow while soil salinity is more than 2%.4. The cotton entire period of water consumption is 506mm, 582mm, 625 and 679mm in turn.when the irrigation quota is 5250m~3/hm~2, the "three-peach" proportion is reasonable, the yield relative high ,and the water use efficiency is also high. In the end, we obtains irrigation regime of Drip Irrigation under Film in salinized land for cotton. |
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