白桦天然次生林土壤有机碳的空间分布特征

Spatial distribution characteristics of soil organic carbon in Betula platyphylla natural secondary forest

为了了解冀北地区白桦天然次生林土壤有机碳的分布特征，以承德市围场县、丰宁县和张家口赤城县白桦天然次生林为研究对象，对其土壤有机碳含量进行了测定分析。结果表明：4个地区的白桦天然次生林各层土壤有机碳含量由高到低顺序依次为赤城县黑龙山、围场县孟滦、丰宁县四岔口、围场县燕格柏，其0～10 cm的土壤有机碳含量依次为108．07 g/kg、65．61 g/kg、52．33 g/kg和30．04 g/kg ；土壤有机碳含量有随海拔升高而上升的趋势；各地区白桦天然次生林的土壤有机碳含量都以表层最高，随着土层深度的增加，土壤有机碳含量呈现逐渐降低的趋势，且随深度的增加，土壤碳含量下降速度逐渐趋缓。

In order to understand how the soil organic carbon is distributed in the Betula p laty p hy lla forests in the north region of Hebei Province .T he Betula p laty p hy lla natural secondary forests were studied ,located in Weichang County ,Fengning County and Chicheng County of north Hebei .The result showed that the soil organic carbon content in soil profile showed a change tendency of Heilongshan Chicheng County ,Mengluan Weichang County , Sichakou Fengning County ,Yangebai Weichang County ,with soil organic carbon contents of 108 .07 g/kg ,65 .61 g/kg ,52 .33 g/kg and 30 .04 g/kg ,respectively .It was found that the soil organic carbon contents raised with the increase of altitude .The soil organic carbon content of surface in soil profile is higher than other layers .With the increase of soil depth ,soil or-ganic carbon content gradually decreased .