水曲柳枯枝落叶分解速率的研究

STUDIES ON THE LITTER DECOMPOSITION RATE OF MANCHURIAN ASH

通过对水曲柳天然林和人工樟子松林两种不同群落类型中水曲柳和樟子松等树种枯叶分解状况的试验研究,结果表明:①水曲柳枯叶分解率在不同群落类型下是不同的。水曲柳林下分解率(57.99％)明显高于樟子松林下的分解率(32.28％);各月总失重率和各标准月(30d)失重率平均高出38.2％和72.9％。②在同一群落类型下水曲柳枯叶与其它树种枯叶分解率存在明显差异,年失重率由大到小顺序为榆树>水曲柳>柞树>樟子松,分别为44.01％,38.28％,26.11％和23.2％。③应用Logistic曲线模型对枯叶各月总失重率变化做了模拟,拟合相关性极为显著,说明枯叶各月总失重率月变化符合Logisitic曲线模型。此外,还用Olson指数衰减模型对枯叶年分解速率及枯叶分解半衰期t_(0.5)和t_(0.95)做了估测。

Through experiment in manchurian ash (Fraxinus mandshurica) natural forest and mongolian scots pine plantation, the manchurian ash and other tree species were studied. (1) The litter decomposition rate of manchurian ash is different in different forest type. The annual weight loss rate of litter in manchurian ash natural forest (57.99％) is higher than that in mongolian scots pine plantation (38.28％); the total monthly proportion of weight losses and the standard monthly (30d) proportion of weight losses are 38.2％ and 72.9％ higher than that in mongolian scots pine plantation. (2) The litter decomposition rate of manchurian ash is significant differ from that of other tree species in mongolian scots pine plantantion. From big to little, the order of annual weight loss rate of litter is japanese elm, manchurian ash, monglian oak and mongolian scots pine and the rate is 44.01％, 38.28％,26.11％ and 23.20％ respectively.(3) The monthly change pattern of weight loss rate of litter fit to Logistic curve model very well and the annual decomposition rate and the half decomposition period (t_(0.5) and t_(0.96)) of litter were estimated by using Olson Exponent Model.