干旱区生态环境知识资源中心(Arid): Carbonate Rhizoliths in Dune Sands of the Belaya River Valley (Upper Angara Region)

Arid

DOI	10.1134/S1064229319010034
	Carbonate Rhizoliths in Dune Sands of the Belaya River Valley (Upper Angara Region)
	Golubtsov, V. A.1,2; Khokhlova, O. S.3; Cherkashina, A. A.1
通讯作者	Golubtsov, V. A.
来源期刊	EURASIAN SOIL SCIENCE
ISSN	1064-2293
EISSN	1556-195X
出版年	2019
卷号	52 期号:1 页码:83-93
英文摘要	Results of investigating carbonate rhizoliths formed in the Early Holocene dune sands in the Belaya River valley are presented. Carbonate accumulations are characterized by large sizes (2 to 7 cm in diameter, and about 1 m in length), which is associated with a high content of carbonates in the enclosing sediments and long-lasting rhizoliths formation. Morphology, mineralogical and isotopic composition of accumulations attest to their origin related to roots and root microorganisms activity. The redistribution of carbonates from the surrounding sediments and their concentration near the roots increased the carbonate content there to more than 30%. With the distance from the roots, the amount of carbonates decreases to 10-12% causing a concentric structure of rhizoliths. In the cross-section of the accumulations, the central and peripheral parts have distinct differences: in the central parts, carbonates are completely recrystallized and represented by pure calcite with insignificant inclusions of quartz and feldspars; on the periphery, coarse-grain silicate material prevails, and it is weakly cemented by clay-carbonate plasma bridges. The C-13 values of carbonates range from -7.4 to -1.5 parts per thousand and increase to the periphery owing to recrystallization of primary carbonates. The C-13 value of the rhizoliths' organic residues is -22.15 parts per thousand indicating the formation of carbonate accumulations around the roots of C3-vegetation. The carbonate O-18 values of rhizoliths vary from 10.34 to -11.99 parts per thousand demonstrating the trend towards O-18 enrichment from the inner to outer layers. Calculation of the annual temperatures using the O-18 values of the inner layers of rhizoliths consisting only of secondary carbonates, showed significant temperature deviations during the formation of carbonate accumulations from modern ones. The radiocarbon age of rhizoliths carbonate cementations (7160 +/- 100 kyr BP) is slightly less than the age of enclosing deposits. Organic residues from the central parts of the rhizoliths are much younger (1770 +/- 40 kyr BP) which is explained by the penetration of organic matter of soils and plant biomass through the cavities which apparently did not cause contamination of the carbonate component of the rhizoliths with younger carbon.
英文关键词	pedogenic carbonate accumulations micromorphology composition of stable isotopes C-14 dating
类型	Article
语种	英语
国家	Russia
收录类别	SCI-E
WOS记录号	WOS:000467465800008
WOS关键词	OXYGEN ISOTOPES ; STABLE CARBON ; PLEISTOCENE ; DESERT ; PALEOSOLS ; DUNEFIELD ; EVOLUTION ; SOILS
WOS类目	Soil Science
WOS研究方向	Agriculture
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/215574
作者单位	1.Russian Acad Sci, Sochava Inst Geog, Siberian Branch, Ul Ulan Batorskaya 1, Irkutsk 664033, Russia; 2.Russian Acad Sci, Siberian Branch, Irkutsk Sci Ctr, Ul Lermontova 134, Irkutsk 664033, Russia; 3.Russian Acad Sci, Inst Physicochem & Biol Problems Soil Sci, Ul Inst Skaya 2, Pushchino 142290, Moscow Oblast, Russia
推荐引用方式 GB/T 7714	Golubtsov, V. A.,Khokhlova, O. S.,Cherkashina, A. A.. Carbonate Rhizoliths in Dune Sands of the Belaya River Valley (Upper Angara Region)[J],2019,52(1):83-93.
APA	Golubtsov, V. A.,Khokhlova, O. S.,&Cherkashina, A. A..(2019).Carbonate Rhizoliths in Dune Sands of the Belaya River Valley (Upper Angara Region).EURASIAN SOIL SCIENCE,52(1),83-93.
MLA	Golubtsov, V. A.,et al."Carbonate Rhizoliths in Dune Sands of the Belaya River Valley (Upper Angara Region)".EURASIAN SOIL SCIENCE 52.1(2019):83-93.