亚洲一区欧美在线,日韩欧美视频免费观看,色戒的三场床戏分别是在几段,欧美日韩国产在线人成

In order to study the adaptability of different tillage treatments in annual double cropping areas in northern China， four different tillage treatments were set up, including subsoiling, rotary tillage, conventional tillage and no-till. The effects of different tillage treatments on soil water stable aggregates, soil bulk density, soil water content, soil temperature and crop growth were studied. The results showed that, no-till and subsoiling increased the content of soil water stable aggregates with a diameter larger than 0.25mm at 0～10cm and 10～30cm soil layer, respectively. While the results of no-till and conventional tillage was not obvious. The regulating effects in soil bulk density were increased with the increase of the depth of soil layer. Rotary tillage and subsoiling could reduce the content of soil bulk density at 0～10cm and 10～30cm soil layer, respectively. The soil bulk density of no-till was the biggest at 0～20cm soil layer, and there were no significant differences observed among the conventional tillage, rotary tillage and no-tillage under 20cm soil layer. The preserve soil moisture ability of subsoiling was higher than others. Compared with subsoiling, the soil moisture content of rotary tillage, plowing tillage and no-tillage was reduced by 2.5%, 1.6%, 0.4%，respectively. The range of soil temperature of plowing tillage was the greatest with the change of air temperature, while the range and daily mean soil temperature of no-till was the least. Subsoiling promoted the yield of winter wheat and the growth of crops in the initial stage, while no-till had a better result at a later stage.