干旱区生态环境知识资源中心(Arid): 黄土的形成与气候旋回划分

Arid

	黄土的形成与气候旋回划分
其他题名	Formation of Loess and Division of Climate Cycles
	赵景波 1; 岳应利 2; 杜娟 1
来源期刊	中国沙漠
ISSN	1000-694X
出版年	2002
卷号	22 期号:1 页码:11-15
中文摘要	根据黄土土壤特征的研究和黄土地层古土壤的识别和划分，结合磁化率测定，研究了黄土剖面冷干与温湿条件下发育的古土壤的分层和代表的气候旋回变化。资料表明，黄土具有土壤的结构和沉积成分，它是在相对冷干气候条件下发育的成熟的灰黄色古土壤，能够可靠地作为冷干气候的指示；250万年来的黄土地层至少可分为51层灰黄色古土壤与50层红褐色古土壤，代表了51个生物、气候、土壤旋回和亚旋回的变化。在50万年来的温湿气候阶段中，气候波动更频繁。
英文摘要	According to the field survey and laboratory analyses of microstructure and susceptibility, the soil character and the climate cycles indicated by paleosol were researched in the paper. Loess has clear soil structure such as granular structure) lumpy structure, similar prismy structure and many holes for plant roots or animal worms. In some layers, there is optically oriented clay film. Secondary CaCO_3 is rich in lo-ess and there is some secondary CaSO_4, in the northwestern loess. They are all illuvial products of soils af-ter being leached. In general, there is organic matter in loess. Sometimes, it appears in the form of black spots, which suggests that it formed in the soil-forming processes. All of them show that loess has the typical soil character in arid areas or semiarid areas and the formation of the loess is soil-forming processes. The development of the loess is very slow and time is long enough for it to become mature paleosol. Because of the cold and arid climate condition then, it didn’t become the red-brown paleosol. Grey-yellow mature soils only could be formed at that time. Loess had been in a stable state and it can be regarded as a reliable indicator for the cold and arid climate. The research material about the climate for soil development and the soil character show that loess is mainly made up of Brown Soils, Sierozems, Chestnut Soils, andBlack Loessial Soils which developed in the steppe and woods-steppe areas. On the basis of the replacement of the loess and the red-brown paleosols, we can divide the creature, climate and soil change cycles.There are 50 layer red-brown paleosols indicating warm and wet climate and 51 layer grey-yellow pal-eosols indicating cold and arid climate in loess strata since 2. 50 Ma BP. They are all macrostropic appear-ance of the creature, climate and soil change for a large range. According to the replacement of these two types of soils, we. can divide the environment change since 2. 50 Ma BP into 51 cycles and sub-cycles. The difference between cycle and sub-cycle can be judged by the degree of the soil development. The paleosols representing climate, cycles developed strongly, while the paleosol representing sub-cycles did weakly. The climate changes more frequently in the warm stages which the red paeosol indicates in the past 500 ka. Comparing the 51 cycles of environment change with the 53 cycles of oxygen isotope in deep-sea deposit, we can conclude that loess strata can be regarded as the standard of the global climate change. What’s more, the oxygen isotope in deep-sea deposit only reflects the temperature and ice volume on the land while loess strata has more environment significance. It can reflect not only temperature and precipitation but al-so the alteration of the plants and soils.
中文关键词	黄土地层 ; 古土壤 ; 环境变化 ; 气候旋回 ; 磁化率
英文关键词	loess strata paleosol environmental change climatic cycle
语种	中文
国家	中国
收录类别	CSCD
WOS类目	MINERALOGY
WOS研究方向	Mineralogy
CSCD记录号	CSCD:1078070
来源机构	陕西师范大学
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/203634
作者单位	1.陕西师范大学地理系, 西安, 陕西 710062, 中国; 2.陕西师范大学物理与信息技术学院, 西安, 陕西 710062, 中国
推荐引用方式 GB/T 7714	赵景波,岳应利,杜娟. 黄土的形成与气候旋回划分[J]. 陕西师范大学,2002,22(1):11-15.
APA	赵景波,岳应利,&杜娟.(2002).黄土的形成与气候旋回划分.中国沙漠,22(1),11-15.
MLA	赵景波,et al."黄土的形成与气候旋回划分".中国沙漠 22.1(2002):11-15.