干旱区生态环境知识资源中心(Arid): Digital mapping of the global soil δ15N at 0.1° x 0.1° resolution using random forest regression with climate classification

Arid

DOI	10.1016/j.ecolind.2023.110974
	Digital mapping of the global soil δ15N at 0.1° x 0.1° resolution using random forest regression with climate classification
	Zan, Qilin; Lai, Xiaoming; Zhu, Qing; Li, Liuyang; Liao, Kaihua
通讯作者	Lai, XM
来源期刊	ECOLOGICAL INDICATORS
ISSN	1470-160X
EISSN	1872-7034
出版年	2023
卷号	155
英文摘要	Spatial information of the natural abundance of soil nitrogen stable isotope (delta N-15) is beneficial for deeply understanding the terrestrial nitrogen (N) cycle. However, to date, the precise global map of soil delta N-15 still lacks. In this study, based on the measured soil delta N-15 data by Craine et al. (2015) (https://doi.org/10.1038/srep08280) and related environmental variables including soil, topography, vegetation, and climate, we constructed the optimal relationship model between soil delta N-15 and environmental variables, and mapped the global pattern of soil delta N-15 at 0.1 degrees x 0.1 degrees resolution (in natural terrestrial ecosystem). Results indicated that satisfied performance was achieved (R-2 = 0.68 and RMSE = 1.26 parts per thousand) by separately building the optimal relationship models for soil delta N-15 in each of five climate zones (Tropical, Arid, Temperate, Cold and Polar) using the random forest regression algorithm. In addition, critical controls of the soil delta N-15 in different climate zones were thus identified based on the variable importance calculated by each random forest regression model. In the Tropical zone, soil delta N-15 might be primarily regulated by microbial N loss, and soil pH and organic matter were identified as two most important factors. In the Arid zone, abiotically gaseous N loss regulated by solar radiation would be the critical controls of soil delta N-15. In the Temperate zone, temperature-related variables were identified as the critical controlling factors, and in the Cold zone, soil water and heat conditions had the equally greater importance, and bulk density was the dominated factor in the Polar zone. Furthermore, the predicted global soil delta N-15 ranged from -0.44 parts per thousand to 12.59 parts per thousand, with the mean value of 5.06 parts per thousand, and the standard deviation of 1.74 parts per thousand. Significantly higher soil delta N-15 (P < 0.05) were observed in the Tropical and Arid zones with mean values of 6.52 parts per thousand and 6.11 parts per thousand, respectively. This indicated that the soil N cycles were more open than those in the Temperate, Cold and Polar zones (mean soil delta N-15 of 4.37 parts per thousand, 3.67 parts per thousand and 2.76 parts per thousand, respectively). This study provides clues for potential environmental regulations on terrestrial N cycle in different climates, and the global soil delta N-15 map can be a reliable data support for future research.
英文关键词	Nitrogen isotope Soil delta N-15 Digital soil mapping Random forest regression Global scale Nitrogen cycle
类型	Article
语种	英语
开放获取类型	gold
收录类别	SCI-E
WOS记录号	WOS:001085247000001
WOS关键词	NITROGEN-CYCLE ; GRADIENT ; PATTERNS ; SYSTEM ; DRIVES ; PLANT ; N-15
WOS类目	Biodiversity Conservation ; Environmental Sciences
WOS研究方向	Biodiversity & Conservation ; Environmental Sciences & Ecology
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/395964
推荐引用方式 GB/T 7714	Zan, Qilin,Lai, Xiaoming,Zhu, Qing,et al. Digital mapping of the global soil δ15N at 0.1° x 0.1° resolution using random forest regression with climate classification[J],2023,155.
APA	Zan, Qilin,Lai, Xiaoming,Zhu, Qing,Li, Liuyang,&Liao, Kaihua.(2023).Digital mapping of the global soil δ15N at 0.1° x 0.1° resolution using random forest regression with climate classification.ECOLOGICAL INDICATORS,155.
MLA	Zan, Qilin,et al."Digital mapping of the global soil δ15N at 0.1° x 0.1° resolution using random forest regression with climate classification".ECOLOGICAL INDICATORS 155(2023).