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于2002年的1月、4月、7月和10月对中亚热带格氏栲和杉木人工林 (monoculture plantations of Castanopsis kawakamii and Cunninghamia lanceolata,33年生) 枯枝落叶层(包括Oi、Oe和Oa层)进行了取样,并采用TOC分析仪测定枯枝落叶层样品的溶解有机碳(DOC)浓度.结果表明,杉木人工林枯枝落叶层DOC平均浓度(1341.7 mg·kg-1)高于格氏栲人工林(1178.9 mg·kg-1).两种林分枯枝落叶层中,Oe层的DOC浓度均高于Oi和Oa层.格氏栲和杉木人工林枯枝落叶层不同分解层次DOC浓度的季节变化模式基本相似,均在秋季或冬季出现最大值.枯枝落叶层DOC浓度及季节变化与温度、湿度、生物活性及枯枝落叶层中有机质数量等有关.表2图2参31.“,”The concentrations and seasonal dynamics of DOC in forest floors of monoculture plantations of Castanopsis kawakamii and Chinese fir (Cunninghamia lanceolata) were assessed in Sanming, Fujian, China (26°11′30″N, 117°26′00″E). Forest floor samples were taken in January, April, July and October in 2002 and divided into undecomposed material (horizon Oi), partially decomposed organic material (horizon Oe), and fully decomposed organic material (horizon Oa). Upon collection, DOC concentrations of samples were analyzed by a High Temperature TOC. The results showed that the annual average DOC concentration of Chinese fir (1341.7 mg·kg-1) in the forest floor was higher than that of Castanopsis kawakamii (1178.9 mg·kg-1). Difference in DOC concentrations was observed among three horizons of the forest floor. DOC concentration of forest floor in the two forests was the highest in horizon Oe. Seasonal trends of DOC concentrations in different horizons of forest floors were similar and the maximal value occurred in autumn (or winter). The concentration and temporal change of DOC in studied forests were probably related to the variation in moisture, temperature, biological activity and quantity of organic matter in the forest floor.