海南岛北部玄武岩上土壤发育过程的定量研究

随着土壤的发育，土壤形态亦会出现相应的变化。对海南岛北部玄武岩上发育的不同成土年龄土壤系列的研究表明，土壤形态特征及其定量化指数，如红化率指数、剖面相对发育指数、土层指数、剖面发育指数等能够较好地反映土壤发育程度和土壤发育的相对年龄，其中剖面发育指数的批示效果最好。

Quantitative Study on the Development of Soils Derived from Basalts in Northern Hainan Island

Soil morphology change systematically with soil development. The soil morphological characteristics had been extensively applied in judging the genesis and development of soils derived from unconsolidated parent materials (e.g. tills, loess, and fluvial, alluvial, lacustrian sediments, etc). Rarely, however, had the research on the development of soils from consolidated bedrocks been done by use of soil morphology. The soils developed from basalts erupted in different periods of Quaternary ranging from 0.01 Ma to 1.81 Ma B P, formed a chronosequence of soils in northern Hainan Island, southern China. The study on the soil chronosequence shows that soil morphological characteristics may also be applied in evaluating the development of soils from bedrocks. And the relationship between the quantitative indices of soil development and soil ages is high. Redness rating (RR), relative profile development (RPD), horizon index (HI), profile development index (PDI) as well as solum thickness increase with soil ages, of which profile development index (PDI), owing to PDI consisting of comprehensive soil characteristics and its rational rating system, is best to assess soil development. Meanwhile, it is noticeable that the soil properties used in some quantitative indices of soil development should be cancelled or added while those indices applied to study on soil development in different conditions.