哀牢山山地黄棕壤腐殖质的研究

云南哀牢山徐家坝自然保护区内,森林经不同程度的破坏后形成的各种次生植被下,土壤有机质含量均有所降低,但H/F值则随森林→灌丛→草地有较大幅度的增加。腐殖质聚合物分子结构中的芳构化度、分子量和芳香环的缩合度由木果石栎林、滇山杨林、毛蕨菜灌草丛到沼泽草地逐渐增大,而腐殖酸分子结构上所带的亲水基侧键则按上述顺序由多到少。

A STUDY ON THE HUMUS IN MOUNTAIN YELLOW-BROWN EARTH OF AILAO MOUNTAIN IN YUNNAN PROVINCE

A study was carried out on the humus in mountain yellow-brown earth of primeval evergreen forest and in different secondary vegetations in Xujiaba Natural Reserve of Ailao Mountain. The results shows that the content of organic matter,the composition and nature of soil humus and the molecular structure of humic acid formed after destruction in different levels will change to a certain extent.After the destruction to the forest,the content of earth organic matter decreases,but the H/F ratio increases rather greatly from forest-shrub-sward. The degree of aromatization,the molecular weight and the condensation of aromatic nucleus in polymer molecular structure of earth humus also increaes gradually from Lithocarpus xylocarpus forest to Populus Ixmatii wood to Ptervtiumreivlutus thicket to swamp meadow while the hydrophilic side-bond on humus molecular structure decreases according to the same order as above.From the comparison, between the humus composition of mountain yellow-brown earth in Ailao Mountain and the same type of earth in other areas of China,The H/F ratio (or R)Oof earth humus is in minus" correlation (P<0. 0. 5)with the latitude(N),and obeys tke exponential regression, with the formula as follow?3. 679e-0.059N, r= -0.8938.