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混剂土系指将吸水剂与土壤混合的土壤.对混入不同吸水剂品种和使用不同比例配成的混剂土的水分特性及其他物理特性进行的研究表明:①把吸水剂加入土壤,可以提高田间持水量,增加有效水含量,混入比例较低时永久凋萎点增高不多.②混剂土具有反复吸水能力,此种能力在实验室内高温烘干的条件下,随吸水—干燥循环次数增加而迅速降低,但在野外自然环境中,降低的速度比较缓慢.③混剂土在室内条件下蒸发速度低于一般土壤;饱和的混剂土无论是放置在室内,还是埋入造林地,其绝对蒸发量均超过对照,但相对蒸发率却都低于对照;蒸发量和蒸发率随吸水剂品种和使用比例的不同而不同;埋入造林地的混剂土,其所含水分向四周水平扩散的距离比对照土壤大,但速度并不很快,且使用比例越高,运动距离越远.④埋入造林地的混剂土,其地表以下10cm处的平均地温在初夏低于对照土壤,且日温差较小.⑤混剂土的膨胀率,品种以IGP最高,THSN-2最小,PPA、HSPAN居中;使用比例以2%最高,1%稍小.⑥使用比例不大的混剂土,其坚实度与一般土壤无异,但使用比例过高时则坚实度明显增加.⑦在北京低山干旱条件下,造林地混剂土中的吸水物质完全降解的时间至少在1年以上,到第3年仍有少量未完全降解的颗粒存在.
Mixed soil refers to the water-absorbent soil mixed with the soil. Mixed with different water-absorbing agent varieties and the use of different proportions of mixed soil moisture characteristics and other physical properties of the study showed that: ① the water-absorbing agent can be added to the soil, Improve the water holding capacity in the field and increase the effective water content, and the percentage of permanent wilting point is lower when the mixing proportion is lower.②The mixed soil has the ability of absorbing water repeatedly, which is with the condition of high temperature drying in the laboratory, The number of cycles increased rapidly and decreased rapidly, but in the natural environment of the field, the rate of decrease was relatively slow.③ The evaporation rate of mixed soil was lower than that of normal soil under indoor conditions. Saturated mixed soil was placed either indoors or in afforestation The absolute evaporation of the soil was higher than that of the control, but the relative evaporation rate was lower than that of the control. The evaporation and the evaporation rate were different with the varieties and the use proportion of the water-absorbing agent. The distance to the surrounding horizontal diffusion is larger than that of the control soil, but the speed is not very fast, and the higher the use ratio is, the farther the movement distance is. (4) The mixed ground soil buried in the afforested land has an average ground temperature of 10cm Summer is lower than the control soil, and the daily temperature difference is smaller .⑤ The swelling rate of mixed soil, the highest IGP varieties, THSN-2 minimum, PPA, HSPAN center; use the highest proportion of 2%, 1% smaller. Small mixed soil, its solidity is no different from the general soil, but the use of the proportion is too high, then the solidity increased significantly.⑦ In the Beijing low mountain drought conditions, the forest soil mixture absorbent material completely degraded time At least a year or more, to the third year there is still a small amount of incomplete degradation of the existence of particles.