棉田土壤养分分析与土壤墒情监测系统应用

【目的】研究土壤养分的空间变异程度及分布规律,为该区域科学施肥提供依据。【方法】以新疆生产建设兵团第八师石河子总场六分场数字农业示范田为研究区域,应用土壤墒情监测系统、GIS与地统计学的方法,对棉田土壤含水量与温度进行实时采集、分析并存储在服务器里面,分析石河子总场土壤含水量和温度变化规律、棉田土壤养分空间分布特点及变异规律。【结果】(1)根据监测数据分析,随着灌水量增加和棉花生育期推进,上层0~30 cm比下层40~60 cm的土壤含水量变化趋势明显。0~20 cm土层土壤补偿水比较充分,各个监测点土壤含水量基本维持在比较适宜的范围内。土壤各层温度受大气温度影响并随着土层深度的加深而减弱,随着土层深度的逐渐加深滞后时间相对延长;受棉株逐渐长高变大以后遮阴等造成的影响,7月以后各土层温度逐渐持平,波动不大。(2)土壤全氮、速效磷和速效钾均呈现出中等程度变异;(3)土壤速效钾的块金值在25%~75%(块金值为0.497)表现为中等空间自相关性外,土壤全氮、速效磷指标的块金系数小于25%表现为强烈的空间自相关性。【结论】应用土壤墒情实时监测系统指导棉田灌溉,较往年没有任何减产减质的情况下,棉花灌溉在全生育期内比以往灌溉次数下降了1~3次,节约水资源约20%左右。研究区域内土壤全氮、速效磷和速效钾变异呈现中等程度变异特征,全氮、速效磷表现为极强空间自相关性,速效钾表现为中等强度的空间相关性。

Soil Nutrient Analysis and Application of Soil Moisture Monitoring System in Cotton Field of Shehizi Farm

【Objective】 To study the degree of spatial variation and distribution of soil nutrients in Shihezi field of the eighth division of Xinjiang Production and Construction Corps with a view of providing the basis for scientific and rational fertilization. 【Methods】 Soil moisture monitoring system, GIS and geostatistics were used to study the variation of soil moisture content and temperature, spatial distribution and variation of soil nutrients in cotton fields. 【Results】 (1) According to the monitoring data analysis, with the increase of irrigation amount and cotton growth period, the change trend of soil water content in the upper layer of 0-30 cm was obvious than that in the lower layer of 40-60 cm soil, the compensation water in 20 cm soil layer was relatively sufficient, and the soil water content at each monitoring point was basically maintained in a more suitable range. The temperature of each layer of soil was affected by the atmospheric temperature and weakened with the depth of soil layer, and the lag time was prolonged with the depth of soil layer. (2) Soil total nitrogen, available phosphorus and available potassium all showed moderate variation; (3) Soil available potassium between 25%-75% (0.497) showed moderate spatial autocorrelation, soil total nitrogen, available phosphorus index of less than 25% showed strong spatial autocorrelation. 【Conclusion】 Using the real-time monitoring system of soil moisture to guide the irrigation of cotton field, the irrigation of cotton decreased by 1-3 times during the whole growing period and saved about 20% of water resources. The variation of soil total nitrogen, available phosphorus and available potassium in the study area showed moderate variation characteristics, total nitrogen and available phosphorus showed strong spatial autocorrelation, and available potassium showed moderate spatial autocorrelation.