Soil Freeze-Thaw and Water Transport Characteristics Under Different Vegetation Types in Seasonal Freeze-Thaw Areas of the Loess Plateau

In the arid and semi-arid regions of the Loess Plateau, seasonal freezing and thawing influence soil water movement, and water movement directly influences vegetation growth. However, currently, research with regard to freezing and thawing processes under various vegetation types and the mechanism of soil water movement is lacking. Therefore, the present study explored soil water migration characteristics of two typical vegetation types [arbor land (AL) and shrub land (SL)] on the Loess Plateau during seasonal freezing and thawing processes using bare land (BL) as a control. We used field measured data for hourly soil temperature (ST) and soil water content (SWC) at a depth of 100 cm below the soil surface from November 2017 to March 2018. Freezing and thawing process was divided into three stages based on ST change (initial freezing period, stable freezing period, and thawing period). Compared with previous studies in this area, ST is lower than expected, and SWC migration characteristics are also different. The results revealed that: 1) the maximum freezing depth of AL and SL was 60 cm, which was 30 cm less than that of BL. The freezing date of each soil layer in BL was the earliest and average ST value was the lowest. BL had the highest degree of freezing. The freezing of all soil layers in AL occurred at a later date than that of SL. ST and the minimum soil freezing temperatures were higher than those of SL, and the capacity of AL to resist freezing was higher; 2) the SWCs in AL and BL at depths of 0–10 cm and 10–30 cm decreased, whereas SWCs of AL and BL at a depth of 60 cm increased by 152 and 146%, respectively. The SWCs of SL at soil depths of 0–10 cm, 10–30 cm, and 30–60 cm increased by 46.3, 78.4 and 205%, respectively. The amount and distribution of soil moisture in SL were optimum when compared to those of AL and BL. The results of the present study could provide a scientific basis for vegetation restoration in arid and semi-arid areas of the Loess Plateau.

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Soil Water Movement Changes Associated with Revegetation on the Loess Plateau of China

Water ◽

10.3390/w11040731 ◽

2019 ◽

Vol 11 (4) ◽

pp. 731 ◽

Cited By ~ 3

Author(s):

Haocheng Ke ◽

Peng Li ◽

Zhanbin Li ◽

Peng Shi ◽

Jingming Hou

Keyword(s):

Soil Water ◽

Loess Plateau ◽

Large Scale ◽

Plant Density ◽

Water Movement ◽

Temporal Distribution ◽

Semiarid Region ◽

The Loess Plateau ◽

Vegetation Growth ◽

Soil Water Movement

Soil water is the limitation factors in the semiarid region for vegetation growth. With the large scale “Grain for Green” implementation on the Loess Plateau of China, an amount of sloping cropland was converted to forestland, shrubland, and grassland. The spatial and temporal distribution of soil water was changed. However, the effect of revegetation on soil water movement is still unclear. In this study, we analyze the stable isotopes changes in precipitation and soil water in sloping cropland, forestland, shrubland, and grassland to trace the movement of moisture in soil. The results showed that δ18O in shallow layers (<20 cm depth) of sloping cropland, forestland, shrubland, and grassland were −3.54‰, −2.68‰, −4.00‰, and −3.16‰, respectively. The δ18O in these layers were higher than that in the lower layers, indicating that evaporation was mainly from the shallow layers. The δ18O for the soil water in the unsaturated zone in the grassland, shrubland, and forestland of the temporal variability decreases with depth and approaches a minimum value at 160 cm, 180 cm, and 200 cm, respectively, suggesting that the soil water is relatively stable many months or even longer. Precipitation was infiltrated with piston and preferential modes, and infiltration demonstrated obvious mixing. Present study demonstrated the δ18O was more sensitive than the soil water content for tracing the maximum infiltration depth of event water and recharge mechanisms. Consequently, we suggested that the land user management such as type, plant density should be considered in the revegetation.

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The influences of air heat storage, plant photosynthesis and soil water movement on surface energy balance over the loess plateau

Acta Physica Sinica ◽

10.7498/aps.61.159201 ◽

2012 ◽

Vol 61 (15) ◽

pp. 159201

Author(s):

Li Hong-Yu ◽

Zhang Qiang ◽

Wang Chun-Ling ◽

Yang Fu-Lin ◽

Zhao Jian-Hua

Keyword(s):

Energy Balance ◽

Surface Energy ◽

Soil Water ◽

Loess Plateau ◽

Surface Energy Balance ◽

Heat Storage ◽

Water Movement ◽

The Loess Plateau ◽

Plant Photosynthesis ◽

Soil Water Movement

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Soil water movement and nutrient cycling in semi-arid rangeland: vegetation change and system resilience

Hydrological Processes ◽

10.1002/(sici)1099-1085(19980315)12:3<443::aid-hyp582>3.0.co;2-n ◽

1998 ◽

Vol 12 (3) ◽

pp. 443-459 ◽

Cited By ~ 38

Author(s):

Andy J. Dougill ◽

A. Louise Heathwaite ◽

David S. G. Thomas

Keyword(s):

Nutrient Cycling ◽

Soil Water ◽

Vegetation Change ◽

Water Movement ◽

System Resilience ◽

Semi Arid ◽

Soil Water Movement ◽

Arid Rangeland

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Soil water availability and holding capacity of different vegetation types in hilly-gullied region of the Loess Plateau

Acta Ecologica Sinica ◽

10.5846/stxb201705170914 ◽

2018 ◽

Vol 38 (11) ◽

Author(s):

李航 LI Hang ◽

严方晨 YAN Fangchen ◽

焦菊英 JIAO Juying ◽

唐柄哲 TANG Bingzhe ◽

张意奉 ZHANG Yifeng

Keyword(s):

Soil Water ◽

Loess Plateau ◽

Water Availability ◽

Soil Water Availability ◽

Vegetation Types ◽

The Loess Plateau

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Stochastic modelling of soil water dynamics and sustainability for three vegetation types on the Chinese Loess Plateau

Soil Research ◽

10.1071/sr18118 ◽

2019 ◽

Vol 57 (5) ◽

pp. 500 ◽

Cited By ~ 1

Author(s):

Lizhu Suo ◽

Mingbin Huang

Keyword(s):

Stochastic Model ◽

Soil Water ◽

Loess Plateau ◽

Water Dynamics ◽

Pinus Tabulaeformis ◽

Soil Conditions ◽

Vegetation Types ◽

The Loess Plateau ◽

Soil Water Dynamics ◽

The Mean

Soil water dynamics play an active role in ecological and hydrologic processes. Soil water exhibits a stochastic nature because of the large temporal variations in precipitation and evapotranspiration. Objectives of this study were to analyse the probabilistic nature of soil water under three vegetation types, to simulate their probability density functions (PDFs) using a stochastic model, and to determine the most sustainable vegetation types. Soil water data were collected over a 3-year period with a bi-weekly frequency at plots in the Loess Plateau, China, under grass (Bothriochloa ischaemum L., BOI), shrub, sea-buckthorn (Hippophae rhamnoides L., SEB) and tree, Chinese pine (Pinus tabulaeformis Carr, CHP). The data were compared with values simulated using the Laio stochastic model. The results showed that the mean relative soil water contents differed in the order: BOI > CHP > SEB. Soil water was related to the daily rainfall and evapotranspiration. Under the same climate, topography and soil conditions, the soil water PDF was sensitive to a critical water content at which plants begin closing stomata and the mean maximum daily evapotranspiration rate. Based on the shape of the PDFs and their statistical moments, the Laio stochastic model accurately simulated the soil water PDFs under all three vegetation types in the semi-humid area of the Loess Plateau. The soil water PDFs for three vegetation types were simulated with four leaf area index scenarios; BOI and CHP were the most sustainable vegetation types compared with SEB in terms of maintaining soil water availability and soil erosion control.

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