内陆盐沼湿地典型植物群落土壤团聚体组成及有机碳粒径分布

Soil aggregate composition and organic carbon particle size distribution of typical plant communities in inland salt marsh wetland

选择兰州市新区秦王川国家湿地公园2种典型植物——群落碱篷(Suaeda salsa)和盐角草(Salicornia europaea)为研究对象,分析了在2种植物群落下土壤团聚体的组成和有机碳的粒径分布状况。结果表明,2种植物群落土壤团聚体含量差异明显,碱蓬群落和盐角草群落在0~30 cm土层土壤团聚体主要以>2 mm和0.5~1 mm粒径团聚体为主。碱篷和盐角草土壤有机碳含量在0~30 cm土层呈V型分布。2种群落在>2 mm和<0.25 mm粒径土壤团聚体有机碳含量最高,但是其对总有机碳的平均贡献率较低,而0.5~1 mm粒径团聚体有机碳含量较低,但其对总有机碳的平均贡献率却高达27.74%,说明了在内陆盐沼>2 mm和<0.25 mm粒径团聚体对土壤有机碳的保护能力较强。土壤总有机碳含量与>2 mm、1~2 mm和0.5~1 mm团聚体含量呈显著(P<0.05)或极显著(P<0.01)正相关。总之,盐角草群落固碳能力更强,提高土壤中>2 mm粒径团聚体的含量能有效增强土壤的抗蚀性,<0.25 mm粒径团聚体可以固持更多稳定的碳源,减少水土流失,提高内陆盐沼湿地固碳能力。

Two typical plant communities,Suaeda salsa and Salicornia europaea,in Qinwangchuan National Wetland Park,new district of Lanzhou city were selected as the research objects,and the composition of soil aggregates and the particle size distribution of organic carbon under the two plant communities were analyzed.The results showed that the contents of soil aggregates in the two plant communities were significantly different,and the aggregates in the soil aggregates in the 0~30 cm soil layer were mainly>2 mm and 0.5~1 mm in particle size.The organic carbon content in the soil of Suaeda salsa and Salicornia europaea showed a V-shaped distribution in the soil layer of 0~30 cm.The content of organic carbon in>2 mm and<0.25 mm particle size aggregates in the two communities was highe,but their average contribution to organic carbon was small.Although the organic carbon in the aggregates was low in the 0.5~1 mm particle sizes,but their average contribution rate was as high as 27.74%.Which indicated that the soil organic carbon was protected by>2 mm and<0.25 mm grain size aggregates in inland salt marshes.Soil organic carbon content was positively correlated with>2 mm,1~2 mm and 0.5~1 mm aggregates(P<0.05).In conclusion,the carbon sequestration capacity of Salicornia europaea community is stronger.Increasing the content of>2 mm particle size aggregates in soil can effectively enhance the soil’s corrosion resistance.The aggregates with particle size<0.25 mm can hold more stable carbon sources,reduce soil erosion,and improve the carbon sequestration capacity of inland salt marsh wetlands.