Study On Water Water-salt Transport Characteristics And Consumption Of Cotton Under Drip Irrigation With Film Mulch In North Xinjiang

The most factor which limits the development of agriculture and economies of Xinjiang is short of water and drought,the water-saving irrigation technique on cotton should be researched furtherly and urgently.The outstanding problem of under-mulch drip irrigation on cotton in expand process is that the irrigation water couldn't moderate to the water requirement of cotton, The soil water-salt control of under-mulch drip irrigation on cotton is not to the utmost reasonable.In order to research on the water consumption and the characteristic of soil water movement and salt transport with cotton under-mulch drip irrigation, the cotton field piot experiment research under-mulch drip irrigation is carried on two years.Based on the experiment research,coming to a few major conclusions as followings:(1) The variation characteristic of soil water and salt about the cotton field before and after irrigation under-mulch drip irrigationAfter irrigation the drip irrigation moisture influence depth of the narrow lines is 60cm,the soil salinity content decreases,the field soil salinity mainly transports and accumulates to the deep depth of the narrow and wide lines under-mulch drip irrigation.The total trend of soil salinity distribution variation is that the earlier stage is relatively high,the middle stage is relatively low,the later period is rising.The soil salinity contents of both narrow line with 20cm and the narrow lines with 40cm are low and the changes are constantly a little,the salinity content of 80cm keeps the accumulated state in the middle and later period.(2)The influence on the salinity transportation under-mulch drip irrigation with different quotasUnder the same irrigation times condition,the soil salinity with the soil of 0-20cm,the smaller the quota is,the higher the salinity content is,while the larger the quota is,the lower the salinity content is;the smaller the quota is, the less obvious the accumulation of salinity is;the larger the quota is ,the larger the horizontal movement distance and the scale of soil moisture are,the higher the soil salinity content is.(3) The influence on the salinity transportation under-mulch drip irrigation with different timesThe more frequency the irrigation times is,the more the influence on the surface soil salinity with irrigation is ,the more obvious the salinity variation is.But witnin drip irrigation influence depth,the more the irrigation times is,the higher the salinity content is.The less the irrigation times is,the larger the soil salinity variation of the wide lines is.The water and salt regulation treatment of comparatively suitable for soil salinity environment of the crops under-mulch drip irrigation is that the irrigation times is 16 and the irrigation quota is 434mm,the irrigation times is 13 and the irrigation quota is 449mm,the irrigation times is 10 and the irrigation quota is 488mm.(4)The characteristic of cotton water consumption in each growth period under-mulch drip irrigationThe irrigation quota and the water consumption are mutually linear related,the cotton water consumption are mainly from the irrigation,but still affected by the rainfall and temperature.with the same or close irrigation quotas,the more the irrigation times is,the larger the water consumption is.The boll stage is the major period of cotton water consumption, the water consumption is the largest,the water consumption proportion takes up about 60%,the water consumption of bud stage is relatively large,the imitation coefficient of water consumption is about 20%,the intensity of seed germination stage is the lowest between 1.39 and 2.15mm/d,the water consumption intensity of bud stage is between 2.58 and 5.29mm/d;the water consumption intensity of the boll stage is at peak,the average is between 4.35 and 6.38mm/d,the water consumption of boll opening decreases,the water consumption intensity decreases between 1.03 and 2.78mm/d.(5)The suitable water consumption and irrigation quota under-mulch drip irrigation in BeijiangTo respectively build inlinear model of crop water production function in the whole growth period according to the two years datas of year 2008 and year 2009,through the solution to the model and the analysis comprehensively,considering that the more the irrigation times is,the less the needed ptional irrigation quota for the cotton to reach the highest yield is,but the higher the highest yield is,the higher the water production rate is.To consider that the suitable irrigation times of the whole growth period for the cotton in Beijiang under-mulch drip irrigation is 16,the water consumption is 438mm,the irrigation quota is 436mm,to build the cotton irrigation system under-mulch drip irrigation initially.