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DOI	10.1016/j.still.2024.106041
	Freeze-thaw effects on pore space and hydraulic properties of compacted soil and potential consequences with climate change
	Kloffel, Tobias; Larsbo, Mats; Jarvis, Nicholas; Barron, Jennie
发表日期	2024
ISSN	0167-1987
EISSN	1879-3444
起始页码	239
卷号	239
英文摘要	Freezing and thawing affect the pore -space structure in agricultural soils with implications for soil hydraulic properties and water flow. Previous studies have focused on the upper few centimeters of the tilled topsoil, where most freeze -thaw (FT) cycles occur, even though deeper soil layers are also subject to freezing and thawing in cold climates. Thus, little is known about how freezing and thawing affect untilled soil layers, which often show high bulk densities that restrict vertical water movement. Furthermore, it remains unclear how shifts in FT patterns with climate change may change the pore -space structure and water flow through these soil layers. Here we investigated the effects of freezing and thawing on X-ray imaged pore -space characteristics, water retention and near -saturated hydraulic conductivity (K) in untilled soil directly below plough depth. Intact cores were sampled at two sites in central Sweden under the same long-term reduced tillage management. The two soils, a silt loam and a silty clay loam, were subjected to three FT scenarios in a laboratory environment intended to represent FT patterns that are considered likely under current and future winter conditions for this region. The latter scenario was characterised by more FT cycles and a lower freezing temperature. Freezing and thawing increased K in the near -saturated range in both soils, which we attribute to observed small (<0.01 mm(3 )mm( -3)) increases in the volume of pores of diameters close to the X-ray resolution limit. Concomitant increases in pore network connectivity and critical pore diameter, especially in the denser silty clay loam soil, probably contributed to this increase in K. The water retention data suggested that changes in pore -space characteristics below X-ray resolution also occurred in both soils. Furthermore, our results indicate that both soils may show higher drainage rates due to shifts in FT patterns in the future, although longer -term changes in pore -space structure with an increasing number of FT cycles would mostly be limited to soils with relatively high clay contents. These soils are often more compacted below plough depth and, thus, benefits from improvements in soil structure such as improved root growth and plant water supply are also expected to be larger.
英文关键词	Temperate -boreal zone; Water retention curve; Hydraulic conductivity; Climate change; Sweden; Ultuna
语种	英语
WOS研究方向	Agriculture
WOS类目	Soil Science
WOS记录号	WOS:001188098600001
来源期刊	SOIL & TILLAGE RESEARCH
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/288513
作者单位	Swedish University of Agricultural Sciences
推荐引用方式 GB/T 7714	Kloffel, Tobias,Larsbo, Mats,Jarvis, Nicholas,et al. Freeze-thaw effects on pore space and hydraulic properties of compacted soil and potential consequences with climate change[J],2024,239.
APA	Kloffel, Tobias,Larsbo, Mats,Jarvis, Nicholas,&Barron, Jennie.(2024).Freeze-thaw effects on pore space and hydraulic properties of compacted soil and potential consequences with climate change.SOIL & TILLAGE RESEARCH,239.
MLA	Kloffel, Tobias,et al."Freeze-thaw effects on pore space and hydraulic properties of compacted soil and potential consequences with climate change".SOIL & TILLAGE RESEARCH 239(2024).