干旱区典型盐生植物群落土壤团聚体组成及有机碳分布

Abstract

PDF HTML阅读 XML下载 导出引用 引用提醒 干旱区典型盐生植物群落土壤团聚体组成及有机碳分布 DOI: 10.5846/stxb201405221057 作者: 作者单位: 石河子大学 石河子,石河子大学 石河子 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金项目(U1203282, 31360320); 教育部科学技术研究项目(213039A) Distribution of soil aggregates and aggregate-associated organic carbon from typical halophyte community in arid region Author: Affiliation: Shihezi University,Shihezi University;China Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:以干旱区玛纳斯河流域扇缘带为研究区,分析了花花柴(Karelinia caspia)、雾冰藜(Bassia dasyphylla)、梭梭(Haloxylon ammodendron)和柽柳(Tamarix ramosissima)4个典型盐生植物群落土壤团聚体的组成及有机碳分布。研究表明:不同植物群落土壤团聚体均以0.25-0.053 mm粒径为主,占了46.7%-74.6%,且与其他粒径差异显著(P < 0.05), > 0.25 mm和 < 0.053 mm粒径土壤团聚体含量较少,仅占7.8%-43%。梭梭群落 > 0.25 mm团聚体平均含量较高,达32%。不同植被群落土壤总有机碳介于2.01-8.73 g/kg之间,不同粒径团聚体有机碳介于1.70-13.68 g/kg之间。不同群落之间,梭梭和柽柳群落总有机碳和团聚体有机碳含量均相对较高,且随着土层深度下降而下降。不同粒径之间,有机碳含量在0.25-0.053 mm粒径最低,在 > 0.25 mm和 < 0.053 mm粒径中最高,呈现"V"型分布且差异显著(P < 0.05)。0.25-0.053 mm团聚体中有机碳含量的贡献率最高,达43.43%,而 < 0.053 mm粒级贡献率较低,但有机碳含量较高,说明了小粒径团聚体对有机碳保护能力较强。土壤有机碳含量与0.25-0.053 mm团聚体含量呈显著负相关(P < 0.05)。而从整体来看,梭梭群落 > 0.25 mm团聚体比例较高,且土壤有机碳和团聚体有机碳含量也较高,说明了在该研究区,梭梭群落聚集土壤养分能力较强,相对其他群落更有利于土壤有机碳的积累。 Abstract:Soil aggregates are organic-inorganic complexes and the basic unit of soil structure. Their formation and stability are closely related to soil organic carbon content. The distribution of aggregate-associated organic carbon determines the capacity for soil organic carbon storage and retention. Currently, research on soil aggregate-associated organic carbon mainly focuses on agricultural and artificial ecosystems; relatively few studies have focused on natural ecosystems. In particular, little is known about distribution of aggregate-associated organic carbon in halophyte communities in Xinjiang. In light of this, a field experiment was conducted on an alluvial fan in the Manasi River Basin to quantify changes in soil aggregation and aggregated-associated soil organic carbon associated with four halophytes (Karelinia caspia, Bassia dasyphylla, Haloxylon ammodendron, and Tamarix ramosissima). Our objective was to determine 1) the particle size that is most conducive to carbon retention and 2) which of the four halophytes is associated with the accumulation of the most soil organic carbon. The results showed: 1) 46.7% to 74.6% of the total soil mass comprised particles of intermediate diameter (0.25-0.053 mm). This was significantly greater (P < 0.05) than the other two classes of particle size defined in this study ( > 0.25 mm and < 0.053 mm). The > 0.25 mm or < 0.053 mm classes only comprised 7.8% to 43% of soil mass. The > 0.25 mm class was most abundant in the Haloxylon ammodendron community, accounting for 32% of soil mass. 2) Soil total organic carbon content was 2.01-8.73 g/kg, and aggregate-associated soil organic carbon content varied from 1.70 to 13.68 g/kg among communities. Total organic carbon and aggregate-associated organic carbon were greater in the Haloxylon ammodendron and Tamarix ramosissima communities than in the other communities studied. These measures decreased in all communities with depth. 3) The aggregate-associated organic carbon content was lowest in the 0.25-0.053 mm class, and significantly higher (P < 0.05) in the >0.25 mm and < 0.053 mm classes. 4) Because the 0.25-0.053 mm class was the most abundant, aggregate-associated organic carbon in this fraction contributed more to soil total organic carbon contained 43.43%. There was more aggregate-associated organic carbon in the < 0.053 mm class, but this contributed less to total soil organic carbon, indicating that these micro-aggregates have the greatest potential to retain soil organic carbon. There was a significant negative relationship between the abundance of 0.25-0.053 mm soil aggregate particles and soil organic carbon content.Total soil organic carbon, aggregate-associated soil organic carbon and abundance of >0.25 mm aggregate particles were highest in the Haloxylon ammodendron community, which implies that this community has the greatest potential to gather soil nutrients of the four communities studies, could be useful for accumulating soil organic carbon in arid areas. 参考文献 相似文献 引证文献