小兴安岭不同类型沼泽湿地土壤碳氮分布特征

Carbon and Nitrogen Distribution Characteristics of Different Kinds of Marsh Wetland in Xiaoxinganling Mountains

[目的]研究小兴安岭不同类型沼泽湿地土壤碳、氮含量。[方法]以小兴安岭3种不同沼泽湿地为对象,研究柴桦苔草沼泽湿地、毛赤杨沼泽湿地和2003年排水造林沼泽湿地土壤碳、氮含量。[结果]3种湿地土壤有机碳(SOC)含量均随土层深度的增加而呈逐渐递减趋势,SOC含量的平均值分别为241.35、141.05、75.89 g/kg。在0~40 cm土层中,SOC含量在不同湿地类型之间存在显著差异,柴桦苔草沼泽湿地最高,显著高于毛赤杨沼泽湿地和03排水造林沼泽湿地(P<0.05)。柴桦苔草沼泽湿地、毛赤杨沼泽湿地及03排水造林沼泽湿地的全氮(TN)平均含量分别为22.88、23.69、9.22 g/kg,柴桦苔草沼泽湿地和毛赤杨沼泽湿地的TN含量显著高于03排水造林沼泽湿地(P<0.05),分别是03排水造林沼泽湿地的2.48倍、2.57倍。微生物生物量碳(MBC)含量由高到低依次为柴桦苔草沼泽湿地、毛赤杨沼泽湿地、03排水造林沼泽湿地,土壤剖面MBC含量均随土层深度的增加而呈递减趋势,在0~10和10~20 cm土层中,柴桦苔草沼泽湿地MBC含量显著高于毛赤杨沼泽湿地和03排水造林沼泽湿地土壤的含量(P<0.05),20~40 cm土层中,柴桦苔草沼泽湿地和毛赤杨沼泽湿地MBC含量显著高于03排水造林沼泽湿地(P<0.05)。3种不同类型的沼泽湿地微生物量熵在0.21%~0.58%,土壤微生物量熵的垂直分布规律不明显。[结论]该研究有助于深入了解小兴安岭森林沼泽湿地碳动态及对排水的响应,为森林湿地生态系统碳循环机制研究提供科学依据。

[ Objective ] To study carbon and nitrogen content of different kinds of marsh wetland in Xiaoxinganling mountains. [ Method ] Choosing three different kinds of wetland in Xiaoxinganling mountains as the object, soil carbon and nitrogen content in Chaihua Carex marsh wetland,Alnus hirsuta marsh wetland and 2003 drainage afforestation marsh wetland were detected. [ Result ] The results showed that organic carbon content in three kinds of wetland decreased with the increase of soil depth, and the average value of SOC content was 241.35,141.05 and 75.89 g,/kg respectively. In 0 -40 cm soil layer, SOC content in different types of wetland existed significant difference, Chaihua Carex marsh wetland was the highest, higher than Alnus hirsuta marsh wetland and 03 drainage marsh wetland（P 〈 0.05 ）. The average content of TN in the Chaihua Carex, Alnus hirsuta and 03 drainage wetland were 22.88,23.69,9.22 g/kg, Chaihua Carex and Alnus hirsuta marsh wetland TN content was significantly higher than that of 03 drainage marsh wetland （ P 〈 0.05 ）, respectively was 2.48, 2.57 times. MBC content was Chaihua Carex 〉 Alnus hirsuta 〉 03 drainage marsh and soil MBC content were decreased with the increase of soil depth and showed decreasing trend. In the 0 - 10 and 10 - 20 cm soil layer, Chaihua Carex MBC content was significantly higher than that ofAlnus hirsutaand and 03 drainage marsh soil content （P 〈0.05）. In 20-40 cm, Chaihua Carex and Alnus hirsuta MBC content was significantly higher than that of 03 drainage marsh wetland （P 〈 0.05 ）. Three types of wetland microbial biamass entropy was O. 21% -O. 58%, the vertical distribution of soil microbial biomass entropy was not obvious. [Conclusion] The study helps to further understand carbon dynamic and response to the drainage of different types of wetland in Xiaoxinganling Mountains, and provides scientific basis for study of carbon cycle mechanism of wetland ecosystem.