五台山土壤水稳性团聚体Ca-SOC和Fe(Al)-SOC分布特征

Distribution Characteristics of Ca-SOC and Fe(Al)-SOC in Soil Water-stable Aggregates in Wutai Mountain

以五台山垂直带土壤为研究对象,按照垂直分布从高到低依次对亚高山草甸土(A)、山地草甸土(B)、棕壤(C)、淋溶褐土(D)和石灰性褐土(E)进行采集,研究土壤本身及各土壤>2,2~0.25,0.25~0.053,<0.053mm水稳性团聚体钙键合有机碳(Ca—SOC)和铁铝键合有机碳(Fe(Al)—SOC)的分布特征。结果表明:从A到E,各土壤Ca—SOC的含量没有明显变化趋势,而Fe(Al)—SOC的含量呈先升高后降低的趋势。随着团聚体粒径的减小,A的Ca—SOC和Fe(Al)—SOC含量变化趋势相反(前者先升高后降低,后者先降低后升高),B的Ca—SOC和Fe(Al)—SOC含量呈先降低后升高的趋势,D的Ca—SOC和Fe(Al)—SOC含量变化趋势与B相反,表现为先升高后降低;此外,C的Ca—SOC和Fe(Al)—SOC含量逐渐减小,而E的Ca—SOC和Fe(Al)—SOC含量逐渐增加。相关性分析表明,各土壤及>2mm团聚体Fe(Al)—SOC与土壤有机碳含量之间呈显著正相关,相关系数分别为r土壤=0.898(P<0.05),r>2mm=0.978(P<0.01)。各土壤及团聚体中Fe(Al)—SOC的含量明显大于Ca—SOC的含量,而且2~0.25mm和0.25~0.053mm团聚体Ca—SOC和Fe(Al)—SOC含量间都呈显著正相关。因此,五台山各土壤铁铝键的键合能力以及铁铝复合体的稳定性均高于Ca—SOC,且土壤和各级团聚体Fe(Al)—SOC的含量及分配比例明显高于Ca—SOC。

In this study,the vertical distributed soils from Wutai Mountain were used as the object,and the subalpine meadow soil（A）,mountain meadow soil（B）,brown soil（C）,leached cinnamon soil（D）and calcareous cinnamon soil（E）were collected from high to low according to the vertical distribution.The distribution characteristics of Ca—SOC and Fe（Al）—SOC in soils and all level water-stable aggregates（〉2 mm,2-0.25 mm,0.25-0.053 mm and〈0.053 mm）were analyzed.The results showed that：From A to E,the content of Ca—SOC in soils didn＇t change significantly,while the content of Fe（Al）—SOC increased firstly and then decreased.With the decrease of aggregates′particle size,the change trend of Ca—SOC and Fe（Al）—SOC′s content in A was opposite（the former increased firstly and then decreased,the latter decreased firstly and then increased）,and decreased firstly and then increased in B.Also,the change trend of Ca—SOC and Fe（Al）—SOC′s content in D was opposite to that of B,which was increased firstly and then decreased.In addition,the Ca—SOC and Fe（Al）—SOC′s content in C decreased gradually,while increased gradually in E.The correlation analysis showed that the soils and 〉2 mm aggregates had a significant positive correlation between Fe（Al）—SOC and TOC,the correlation coefficient were rsoil=0.898（P〈0.05）and r2 mm=0.978（P〈0.01）.The content of Fe（Al）—SOC in soils and all level aggregates was significantly higher than that of Ca—SOC,and the contents of Ca—SOC and Fe（Al）—SOC in 2-0.25 mm and 0.25-0.053 mm aggregates were significantly positive correlated.Therefore,in Wutai mountain soil,the bonding ability of Fe—Al bond and the stability of Fe—Al complex were higher than Ca—SOC,besides,the content and distribution ratioof Fe（Al）—SOC in soil and all level aggregates were significantly higher than that of Ca—SOC.