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Abstract Arid and semiarid ecosystems around the world are often prone to both soil salinization and accelerated soil erosion by wind. Soil salinization, the accumulation of salts in the shallow portions of the soil profile, is known for its ability to decreases soil fertility and inhibit plant growth. However, the effect of salts on soil erodibility by wind and the associated dust emissions in the early stages of soil salinization (low salinity conditions) remains poorly understood. Here we use wind tunnel tests to detect the effects of soil salinity on the threshold velocity for wind erosion and dust production in dry soils with different textures treated with salt‐enriched water at different concentrations. We find that the threshold velocity for wind erosion increases with soil salinity. We explain this finding as the result of salt‐induced (physical) aggregation and soil crust formation, and the increasing strength of surface soil crust with increasing soil salinity, depending on soil texture. Even though saline soils showed resistance to wind erosion in the absence of abraders, the salt crusts were readily ruptured by saltating sand grains resulting in comparable or sometimes even higher particulate matter emissions compared to non‐saline soils. Interestingly, the salinity of the emitted dust is found to be significantly higher (5–10 times more) than that of the parent soil, suggesting that soil salts are preferentially emitted, and airborne dust is enriched of salts.
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Formulating Zwitterionic, Responsive Polymers for Designing Smart Soils
Abstract The design of new remediation strategies and materials for treating saline–alkaline soils is of fundamental and practical importantance for many applications. Conventional soil remediation strategies mainly focus on the development of fertilizers or additives for water, nutrient, and heavy metal managements in soils, but they often overlook a soil sensing function for early detection of salinization/alkalization levels toward optimal and timely soil remediation. Here, new smart soils, structurally consisting of the upper signal soil and the bottom hygroscopic bed and chemically including zwitterionic, thermo‐responsive poly(NIPAM‐co‐VPES) and poly(NIPAM‐co‐SBAA) aerogels in each soil layer are formulated. Upon salinization, the resultant smart soils exhibit multiple superior capacities for reducing the soil salinity and alkalinity through ion exchange, controlling the water cycling, modulating the degradation of pyridine‐base ligands into water‐soluble, nitrogenous salts‐rich ingredients for soil fertility, and real‐time monitoring salinized soils via pH‐induced allochroic color changes. Further studies of plant growth in smart soils with or without salinization treatments confirm a synergy effect of soil remediation and soil sensing on facilitating the growth of plants and increasing the saline–alkaline tolerance of plants. The esign concept of smart soils can be further expanded for soil remediation and assessment.
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- Award ID(s):
- 1806138
- PAR ID:
- 10372278
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Small
- Volume:
- 18
- Issue:
- 38
- ISSN:
- 1613-6810
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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