我国中亚热带山地土壤有机质研究

Studies on Organic Matter of Mountain Soil in Mid-subtropical Zone in China

本文研究中亚热带地区湖南连云山、万洋山各垂直地带的A层土壤的有机质某些性质的垂直变化规律。TC、TN、Kos、HA FA、总酸度、羧基和酚羟基含量均表现为随海拔的增高而增加的趋势 ,E4 E6的结果则相反。Ca键腐殖质变化不明显 ,Fe .Al键腐殖质、紧结态腐殖质均随海拔的升高而增加。G0 %和G1 %含量随海拔的升高而减小 ,G2 %含量随海拔的升高而增加 ,G1 G2 比值表现为基带土壤 >0 .5 ,而山地土壤 <0 .5。基带土壤中G2 组有机碳在复合体有机碳总量中所占的比例较小 ,山地土壤中G2 组有机碳占的比例却最大 ,都超过 5 0 %。聚类分析表明海拔高度对低海拔和高海拔地带土壤的有机质性质的影响小于中间过渡地带。

A study was carried out to know the vertical change of the properties of mountain soils in Mid subtropical zone in China with altitude. Sampling the surface soils from the south slope of the Lianyun Mountain and the west slope of the Wanyang Mountain in Hunan province, this paper reveals the properties of organic matter including TC, TN, Kos, HA/FA, total acidity, carboxyl group and phenolic hydroxyl group increase with the ascend of altitude, but the E 4/E 6 ratio is opposite. The content of the calcium bound humus is low, and doesn't show the obvious change with the altitude. And the contents of the iron and aluminum bound humus and the tightly combined humus increase with the rise of altitude. The amount of G 0% and G 1% decreases whereas the amount of G 2% increases with the rise of altitude. The ratio of G 1 to G 2 is higher in basic soil than in mountain soil. The former is more than 0.5, and the latter is less than 0.5. The percentage of G 0 and G 1 organic carbon in the total organic carbon of organo mineral complexes decreases quickly with the rise of altitude, but that of the G 2 fraction is opposite. In basic soil, the organic carbon of G 2 fraction is less than that of the other two fractions, and it is the most content of the three fractions in mountain soil, which is more than 50%. Therefore, the G 0 and G 1 fractions contribute much to the soil fertility in basic soil, and so does the G 2 fraction in mountain soil. Cluster analysis is used in the Lianyun mountain soils and the Wanyang mountain soils respectively. The properties of soil organic matter in bottom and upper zone of the mountain are more influenced by the altitude than in middle zone.