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用严重酸化的挪威云杉林的枯落物和矿质土壤,研究了温度和含水量对有机质分解过程中重量和碳的气态损失的影响。在为期1a的室内试验期间,没有元素的输入、淋失和植物根系吸收。实验分3个温度处理(年均温度分别为11.6、12.3和14.5℃)和4个水分处理(从几乎风干到各种被分解物的饱和含水量)。在有利条件下,枯落物未分解层OL的重量损失速率是半分解层OF的2倍和已分解层OH的5～6倍。矿质土壤的重量损失速率小于枯落物层。分解速率在很大程度上受控于环境条件,其中含水量起着决定性作用。极端干旱会使分解速率非常低,水分过多时也会限制土壤微生物活动,最适宜的含水量为各种被分解物饱和含水量的70%～90%。在应用的温度范围内,温度差别只起着次要作用。被分解物在土壤剖面中所处的位置越深,含水量越低,温度的影响越小。建立了符合土壤有机质分解机制的重量损失和碳损失的数学模型。
The effects of temperature and water content on the weight loss of carbon and the loss of carbon during organic matter decomposition were studied using litter and mineral soils of severely acidified Norway spruce forest. During the 1a indoor test, there were no elemental inputs, leaching and plant root absorption. The experiment was divided into three temperature treatments (average annual temperature of 11.6, 12.3 and 14.5 ℃ respectively) and four treatments of water (from almost air-dried to the saturated water content of various decomposed products). Under favorable conditions, the weight loss rate of the litter undecomposed layer OL is twice that of the semi-decomposed layer OF and 5-6 times that of the decomposed layer OH. The weight loss rate of mineral soils is less than that of litter. The rate of decomposition is largely controlled by the environmental conditions in which water content plays a decisive role. Extreme drought can cause very low rates of decomposition. When there is too much water, the activities of soil microorganisms are also limited. The most suitable water content is 70% -90% of the saturated water content of various decomposition products. Within the temperature range of application, temperature differences play only a secondary role. Decomposed objects in the soil profile where the deeper, the lower the water content, the smaller the impact of temperature. A mathematical model of weight loss and carbon loss in soil organic matter decomposition mechanism was established.