ass日本风韵熟妇pics男人扒开女人屁屁桶到爽|扒开胸露出奶头亲吻视频|邻居少妇的诱惑|人人妻在线播放|日日摸夜夜摸狠狠摸婷婷|制服 丝袜 人妻|激情熟妇中文字幕|看黄色欧美特一级|日本av人妻系列|高潮对白av,丰满岳妇乱熟妇之荡,日本丰满熟妇乱又伦,日韩欧美一区二区三区在线

In order to explore the impact of water-saving renovation projects on soil salinization in Hetao Irrigation District, Yongji in Hetao Irrigation District which was a typical salinization region was taken as an example. The implementation stages of water-saving renovation projects were divided into four periods, and the land use types and the soil salinity at the depth of the soil layer was interpreted based on remote sensing technology. The temporal and spatial evolution of soil salinization in different water-saving renovation periods was analyzed from the spatial distribution state of soil salinity and the time evolution of soil salinity indicators (total salt storage and unit salt storage). From the point scale and regional scale, the response of soil salinization to groundwater and the evolution mechanism of soil salinization in combination with irrigation, drainage and other factors in irrigation areas were comprehensively analyzed. The results showed that with the implementation of the water-saving renovation project, the spatial distribution of soil salinization degree showed trend of lower in the south and higher in the north, which gradually became obvious. The areas with the highest salinization level were salinized wasteland. Compared with 2000, the degree of soil salinization was increased from 2005 to 2010 with the main performance that the proportion of strongly saline soil (mainly salinized grades) in spring and autumn were increased by 106.98%~806.38% and 44.26%~190.60%, respectively. From 2010 to 2015, the degree of soil salinization was gradually decreased, and the main salinization level shifted to a smaller level. From 2015 to 2021, the degree of soil salinization was decreased more significantly, the sum of the proportions of moderately and strongly saline soil (mainly the salinization level) of 0~20cm in spring was decreased by 9.15% on average, and the sum of the proportions of lightly and moderately salinized soils (mainly salinized levels) of 20~40cm in spring, 0~20cm and 20~40cm in autumn were increased by 15.02%, -2.62% and 6.26% compared with that in 2005—2010, respectively. With the progress of the water-saving renovation project, the salt storage in the 0~40cm soil layer was increased first and then decreased in spring and autumn, and reached the maximum value in 2010, of which the total salt storage was 1.489×106t and 1.396×106t in the 0~20cm spring and autumn, respectively. By 2021, the average total salt storage in spring and autumn was still greater than that in 2000. The soil salinity and groundwater burial depth in different periods had a logarithmic relationship with determination coefficient R2 of 0.744 and 0.672 in spring and autumn, respectively. The average groundwater depths of slightly saline soil, moderately saline soil, strongly saline soil and solonchak soil in spring and autumn was 2.351m, 2.144m, 1.953m and 1.752m, respectively. The average groundwater depths in autumn was 7.85%, 8.27%, 12.16% and 9.88% smaller than those in spring, respectively.