Study On The Drip Irrigation System And The Location Of Soil Moisture Measuring Points Under The Mulch Of Mechanized Cotton In South Xinjiang

In order to improve the rationality of soil moisture sensor layout and irrigation decision-making in Xinjiang cotton field intelligent drip irrigation control system,the experiment was carried out in the first water conservancy experimental station of Tarim River Basin in southern Xinjiang.Aiming at the problems of less research on the location of soil moisture measurement points and low water use efficiency of cotton field under drip irrigation under machine harvesting plastic film in southern Xinjiang,the efficient application strategy of water saving and accurate distribution of soil moisture measuring points were realized The effects of different water treatments on soil moisture content,cotton growth index and yield were studied.The irrigation application mode suitable for the sustainable development of cotton industry and the location and quantity of soil moisture measuring points in irrigation growth period were discussed.Two irrigation cycles?5 and 7 days?were set in the irrigation growth period?bud stage and flowering and boll stage?;three levels of irrigation quota were set:I0.6?difference between 60%ETgage evapotranspiration and effective rainfall?,I0.8?difference between 80%ETgage evapotranspiration and effective rainfall?and I1.0?difference between 100%ETgage evapotranspiration and effective rainfall?.Six treatments were set,with three replicates in each treatment.The main conclusions are as follows:?1?Soil moisture content of different water treatments showed that before irrigation,the average soil moisture content of each treatment decreased slightly;after irrigation,the average soil moisture content of each treatment increased significantly,and increased with the increase of irrigation quota.In the whole soil profile water change process,the horizontal direction,with the increase of the distance from the drip irrigation belt,the soil moisture content of 0¹0 cm gradually decreased,showing the following order:under the belt>narrow line>bare land.?2?In the whole process of cotton growth,cotton plant height,leaf area index?LAI?peak value and water consumption were positively correlated with irrigation quota,which increased with the increase of irrigation quota,and the water use efficiency(WUE_ET)was on the contrary;the total aboveground dry matter of cotton plants first increased and then decreased with the increase of irrigation quota;seed cotton yield was positively correlated with the corresponding aboveground The total dry matter accumulation was positively correlated.When irrigation quota was the same,cotton plant height increased with the decrease of irrigation period;Lai of treatment with small irrigation cycle reached the peak first;water consumption of treatment with small irrigation cycle was small,but WUE_ETT increased;the treatment with irrigation cycle of 5 days,irrigation quota of I0.8 and final irrigation quota of 394.0 mm had the highest seed cotton yield,seed cotton yield was6 471.39 kg/hm²,and water use efficiency was 1.35 kg/m³ is the suitable irrigation system for cotton.?3?If there is only one sensor,the sensor of bud stage can be embedded in the depth of36 cm,25 cm away from the center of the film;the sensor of florescence can be embedded in the depth of 29 cm,50 cm from the center of the film in flowering stage;the sensor of boll stage can be embedded in the depth of 32 cm,21 cm from the center of the film;the sensor of bud and boll stage can be embedded in the depth of 31 cm,24 cm from the center of the film in the irrigation and growth period.?4?For a 200 mu rotation irrigation strip field,the number of sensors is 6 respectively.When the local optimal soil moisture measuring points are arranged in the field,the spacing should be greater than 122 m.