Effect of the colloidal component of soils on the moisture of limited availability of water and water retention

Abstract

Abstract The decrease in water mobility when the hydrological moisture constant of point of limited availability of water (PLAW) is reached is explained by the presence of film forms of water formed under the influence of the solid phase. It is also known that the existence of such forms of water is limited by the concentration of electrolytes. The aim of the work was to clarify the mechanism of water stabilization by the solid phase of soils in point of limited availability of water, taking into account the colloidal component of soils. The studies were carried out on samples from sod-podzolic and gray forest soils and chernozem. In the work, the value of the PLAW was determined by plotting the secant on the curve of the main hydrophysical characteristic obtained by centrifugation. Scanning electron microscopy, vibrational viscometry, and a technique for extracting gels from soils were also used. During the experiments, it was found that adding 1 n of potassium chloride solution to the soil, compressing the double electric layer on the surface of the particles, does not reduce the value of the PLAW. This suggests that the film forms of water in PLAW are stabilized by soil organomineral gels, since at such concentrations of salts, water films cannot exist in free form. It was also found that an increase in the number of gels in soils by their introduction increases the PLAW of the soil sample, and a decrease in the volume of soil gels leads to a decrease in PLAW. Thus, it is shown that water in case of PLAW is a part of the colloidal component of soils — soil organomineral gels, and the value of PLAW in soils depends on the number and volume of these gels.

References

1.    Болотов А.Г., Шеин Е.В., Макарычев С.В. Водоудерживающая способность почв Алтайского края // Почвоведение. 2019. № 2. С. 212-219.
2.    Воронин А.Д. Структурно-функциональная гидрофизика почв. М., 1984. 202 с.
3.    Воюцкий С.С. Курс коллоидной химии. М., 1975. 512 с.
4.    Габуда С.П., Ржавин А.Ф. ЯМР в кристаллогидратах и гидратированных белках. Новосибирск, 1978. 160 с.
5.    Дерягин Б.В., Чураев Н.В., Муллер В.М. Поверхностные силы. М., 1987. 398 с.
6.    Дымов А.А., Милановский Е.Ю., Холодов В.А. Состав и гидрофобные свойства органического вещества денсиметрических фракций почв Приполярного Урала // Почвоведение. 2015. № 11. С. 1335–1335.
7.    Полевые и лабораторные методы исследования физических свойств и режимов почв: Методическое руководство / Под ред. Е.В. Шеина. М., 2001. 200 с.
8.    Роде А.А. Основы учения о почвенной влаге. Т. 1: Водные свойства почв и передвижение почвенной влаги. Л., 1965. 664 с.
9.    Семенов В.М., Лебедева Т.Н., Паутова Н.Б. Дисперсное органическое вещество в необрабатываемых и пахотных почвах // Почвоведение. 2019. № 4. С. 440–450.
10.    Судницын И.И. Движение почвенной влаги и водопотребление растений. М., 1979. 255 с.
11.    Федотов Г.Н., Шеин Е.В., Ушкова Д.А. и др. Надмолекулярные образования из молекул гуминовых веществ и их фрактальная организация // Почвоведение. 2023а. № 8. С. 903–910.
12.    Федотов Г.Н., Шоба С.А., Ушкова Д.А. и др. Гуминовые вещества и вязкость почвенных паст // Доклады Российской академии наук. Науки о Земле. 2023б. Т. 511, № 1. С. 119–123.
13.    Шеин Е.В., Милановский Е.Ю. Органическое вещество и структура почвы: учение В.Р. Вильямса и современность // Известия Тимирязевской сельскохозяйственной академии. 2014. № 1. С. 42–51.
14.    Шеин Е.В., Торбик Е.А. Изучение гидрологии почвенных конструкций в лабораторных физических и прогнозных математических моделях // Вестник Оренбургского государственного университета. 2014. Т. 6, № 167. С. 218–223.
15.    Шеин Е.В., Девин Б.А. Современные проблемы изучения коллоидного транспорта в почве // Почвоведение. 2007. № 4. С. 438–449.
16.    Юдина А.В., Фомин Д.С., Котельникова А.Д. и др. От понятия элементарной почвенной частицы к гранулометрическому и микроагрегатному анализам (обзор) // Почвоведение. 2018. № 11. С. 1340–1362.
17.    Ai Y., Zhao C., Sun L. et al. Coagulation mechanisms of humic acid in metal ions solution under different pH conditions: A molecular dynamics simulation // Science of the Total Environment. 2020. Vol. 702. P. 135072. https://doi.org/10.1016/j.scitotenv.2019.135072
18.    Alvarez-Puebla R.A., Goulet P.J.G., Garrido J.J. Characterization of the porous structure of different humic fractions // Colloids and Surfaces A: Physicochemical and Engineering Aspects. 2005. Vol. 256, № 2–3. P. 129–135. https://doi.org/10.1016/j.colsurfa.2004.12.062
19.    Angelico R., Colombo C., Di Iorio E. et al. Humic substances: from supramolecular aggregation to fractal conformation — is there time for a new paradigm? // Applied Sciences. 2023. Vol. 13, № 4. P. 2236. https://doi.org/10.3390/app13042236
20.    Boguta P., D'Orazio V., Senesi N. et al. Insight into the interaction mechanism of iron ions with soil humic acids. The effect of the pH and chemical properties of humic acids. // Journal of Environmental Management. 2019. Vol. 245. P. 367–374. https://doi.org/10.1016/j.jenvman.2019.05.098
21.    Chibowski E. Flocculation and dispersion phenomena in soils // Encyclopedia of Agrophysics. Springer, Dordrecht, 2011. P. 301–304. https://doi.org/10.1007/978-90-481-3585-1_59
22.    Colopietro D.J., Pachon J., Bacon A. Investigating soil properties influencing the depth and degree of lessivage in Florida soils using a random forest modeling approach // Geoderma Regional. 2025. Vol. 40. P. e00916. https://doi.org/10.1016/j.geodrs.2025.e00916
23.    De Melo T.R., Figueiredo A., Tavares Filho J. Clay behavior following macroaggregate breakdown in Ferralsols // Soil and Tillage Research. 2021. Vol. 207. P. 104862. https://doi.org/10.1016/j.still.2020.104862
24.    Deb D., Chakma S. Colloid and colloid-facilitated contaminant transport in subsurface ecosystem—a concise review // International Journal of Environmental Science and Technology. 2023. Vol. 20, № 6. P. 6955–6988 https://doi.org/10.1007/s13762-022-04201-z
25.    Goldberg S., Forster H.S. Flocculation of reference clays and arid‐zone soil clays // Soil Science Society of America Journal. 1990. Vol. 54, № 3. P. 714–718. https://doi.org/10.2136/sssaj1990.03615995005400030014x
26.    Jeong S.W., Locat J., Torrance J.K. et al. Thixotropic and anti-thixotropic behaviors of fine-grained soils in various flocculated systems // Engineering Geology. 2015. V. 196. P. 119–125. DOI: 10.1016/j.enggeo.2015.07.014
27.    Krause L., Klumpp E., Nofz I. et al. Colloidal iron and organic carbon control soil aggregate formation and stability in arable Luvisols // Geoderma. 2020. Vol. 374. P. 114421. https://doi.org/10.1016/j.geoderma.2020.114421
28.    Kretzschmar R., Robarge W.P., Weed S.B. Flocculation of kaolinitic soil clays: Effects of humic substances and iron oxides // Soil Science Society of America Journal. 1993. Vol. 57, № 5. P. 1277–1283. https://doi.org/10.2136/sssaj1993.03615995005700050019x
29.    Laird D. Nature of clay–humic complexes in an agricultural soil: II. Scanning electron microscopy analysis // Soil Science Society of America Journal. 2001. Vol. 65, № 5. P. 1419–1425. https://doi.org/10.2136/sssaj2001.6551419x
30.    Li W., Yan J., Afsar M.Z. et al. Size-dependent mobility of soil colloids and associated organic carbon loading capacity following stepwise decreases in redox potential // Geoderma. 2024. Vol. 448. P. 116955. https://doi.org/10.1016/j.geoderma.2024.116955
31.    Li X., Yao S., Liao R. Effects of Humic Acid on the Adsorption of Phosphorus by Colloids and the Kinetic Behavior of Colloid Aggregation // Water, Air, & Soil Pollution. 2025. Vol. 236, № 10. P. 1–15. https://doi.org/10.1007/s11270-025-08286-3
32.    Liu J., Wang J., Jiang C. et al. A screening model for predicting the potential of soil colloids-enhanced leaching of hydrophobic organic contaminants to groundwater at contaminated sites // Journal of Environmental Sciences. 2025. Vol. 150. P. 309–317. https://doi.org/https://doi.org/10.1016/j.jes.2024.03.008
33.    Negre M., Leone P., Trichet J. et al. Characterization of model soil colloids by cryo-scanning electron microscopy // Geoderma. 2004. Vol. 121, № 1–2. P. 1–16. https://doi.org/10.1016/j.geoderma.2003.09.011
34.    Zhang Q., Bol R., Amelung W. et al. Water dispersible colloids and related nutrient availability in Amazonian Terra Preta soils // Geoderma. 2021. Vol. 397. P. 115103. https://doi.org/10.1016/j.geoderma.2021.115103