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在室内控制条件下研究了含水量和温度对富含ＮＨ＋４的严重酸化挪威云杉林枯枝落叶层物质饱和浸提液ｐＨ值的影响，包括未分解层ＯＬ、半分解层ＯＦ和已分解层ＯＨ，在为期１ａ的实验期间内没有元素的输入、淋失和根系吸收，但可相对自由地进行气体交换。实验分４个水分处理（从几乎风干到各种被分解物的饱和含水量）和３个温度处理（年均温度分别为１１．６、１２．３、１４．５℃）。干旱使枯枝落叶浸提液ｐＨ值明显下降，极端干旱条件下Ｈ＋饱和浸提量为初始值的２．２～２．７倍。为避免ｐＨ值急剧下降，枯枝落叶层的含水饱和度应维持在６０％～８０％。如果ＯＬ的含水饱和度小于３０％，ＯＦ和ＯＨ小于５０％，则浸提液ｐＨ值低于初始值。干旱条件下，富含ＮＨ＋４的酸化枯枝落叶也会发生氨挥发，并且在ｐＨ值下降中起着十分重要的作用。在应用温度范围内，温度差别对ｐＨ值变化的影响很小
The effect of water content and temperature on the pH value of the saturated extract of litter layer enriched with NH + 4 in severely acidified Norway spruce plantations was investigated under laboratory conditions, including the unconsolidated layer OL, the semi-decomposed layer OF and the decomposed layer OH, there is no elemental input, leaching and root absorption during the experiment period la, but gas exchange is relatively free. The experiment was divided into 4 water treatments (from almost air-dried to saturated water content of various decomposed matters) and 3 temperature treatments (average annual temperature of 11.6, 12.3 and 14.5 ℃, respectively). Drought to the litter leaf extract pH decreased significantly under extreme drought H + saturated extract of 2.2 to 2.7 times the initial value. In order to avoid sharp drop of pH, the water saturation of litter layer should be maintained at 60% ~ 80%. If OL’s water saturation is less than 30% and OF and OH are less than 50%, the pH of the leachate is lower than the initial value. Ammonia volatilization also occurs in the acidified litter that is rich in NH + 4 under drought conditions and plays a very important role in pH drop. Within the application temperature range, temperature differences have little effect on the pH change