气候变化领域集成服务门户(CCPortal): The role of topography in shaping the spatial patterns of soil organic carbon

CCPortal

DOI	10.1016/j.catena.2019.01.029
	The role of topography in shaping the spatial patterns of soil organic carbon
	Zhu, Meng; Feng, Qi; Qin, Yanyan; Cao, Jianjun; Zhang, Mengxu; Liu, Wei; Deo, Ravinesh C.; Zhang, Chengqi; Li, Ruolin; Li, Baofeng
发表日期	2019
ISSN	0341-8162
EISSN	1872-6887
卷号	176
英文摘要	In regions with a relatively complex topography, the soil organic carbon (SOC) is characterized by a high spatial heterogeneity, which is likely to contribute to large uncertainties in the regional SOC estimation. Generally, the elevation and aspect are expected to be the two main topographic controls of the spatial patterns of SOC on steep hillslopes. However, the manner in which the aspect-induced variability in SOC varies with elevation zone is still less understood. In this study, SOC in three elevation-dependent vegetation zones (similar to 2450 m: the shrub-steppe zone, similar to 2900 in: the forest-steppe zone, and similar to 3350 m: the shrub-meadow zone) was examined in the Qilian Mountains. Soil samples at 0-10, 10-20, 20-40, and 40-60 cm were collected on the south-, southwest-, west-, northwest-, and north-facing slopes with similar slope gradients (similar to 32 degrees) in each of the three vegetation zones. The results showed that the SOC density tends to increase following the elevation zone, with an average density of about 24.30 kg m(-2) at the 0-60 cm. In addition, the SOC concentration appeared to have increased with the cosine of the aspect following an exponential function. The average rate of increase in terms of the aspect at 0-10 cm in the forest-steppe zone was approximately 0.46 g kg(-1) degree(-1), which amounted to 1.39 and 2.19 fold greater than in the shrub-steppe and shrub-meadow zones, respectively. Path analysis performed using structural equation modelling (SEM) demonstrated that the elevation and the aspect had an indirect influence on the SOC density, through a direct effect on the soil temperature, vegetation type, and soil moisture, and this could possibly explain 88% of the total variation in the SOC density. The present results suggest that the forest-steppe zone is characterized by the strongest aspect effect on SOC in comparison with the shrub-steppe and shrub-meadow zones, and confirm the importance of elevation and aspect in shaping the spatial patterns of SOC.
关键词	Soil organic carbon Elevation Aspect Vegetation type Structural equation modelling
学科领域	Geology; Agriculture; Water Resources
语种	英语
WOS研究方向	Geosciences, Multidisciplinary ; Soil Science ; Water Resources
来源期刊	CATENA
来源机构	中国科学院西北生态环境资源研究院
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/112083
作者单位	Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Key Lab Ecohydrol Inland River Basin, Lanzhou 730000, Gansu, Peoples R China
推荐引用方式 GB/T 7714	Zhu, Meng,Feng, Qi,Qin, Yanyan,et al. The role of topography in shaping the spatial patterns of soil organic carbon[J]. 中国科学院西北生态环境资源研究院,2019,176.
APA	Zhu, Meng.,Feng, Qi.,Qin, Yanyan.,Cao, Jianjun.,Zhang, Mengxu.,...&Li, Baofeng.(2019).The role of topography in shaping the spatial patterns of soil organic carbon.CATENA,176.
MLA	Zhu, Meng,et al."The role of topography in shaping the spatial patterns of soil organic carbon".CATENA 176(2019).