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Abstract AimsThe goal of this study was to explore the suitability of recycled glass sand for the growth of beach-adapted plant species given the potential environmental benefits of utilizing glass sand for beach and dune restoration in the face of dwindling natural sand resources. MethodsWe grew three species native to US Gulf of Mexico beaches (Ipomoea imperati(Vahl) Griseb.,I. pes-caprae(L.) R.Br., andUniola paniculata(L.)) in three greenhouse experiments in glass sand, beach sand, or mixtures. First, we investigated nutrient and microbial effects by growing each species in pure glass sand, beach sand, and 80%/20% mixtures of glass sand/beach sand. Second, we comparedU. paniculatagrowth in glass sand mixed with 100%, 75%, 50%, 25%, or 0% beach sand. These experiments included fertilizer and microbial sterilization treatments. Third, we investigated soil permeability effects by comparing growth of all species using different grain sizes of glass sand. ResultsOverall, plants produced significantly more biomass in beach sand than in glass sand, and the effect was more pronounced with the fertilizer treatment. There were significant effects of substrate mixtures and interactions with fertilizer treatments onUniolabiomass. Further, when glass sand grain sizes were manipulated, plant biomass was equal or higher in the coarsest glass sand compared to beach sand. ConclusionsOur results demonstrate that beach-adapted plants can grow in glass sand and suggest that recycled glass sand is a potential resource for ecological restoration with incorporation of soil amendments such as fertilizer and utilization of selected grain sizes.
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This content will become publicly available on June 24, 2026
Physical and chemical characterization of recycled glass sand for environmental restoration
Abstract IntroductionWe rely on coastal resources for food, water, and energy. However, over 75% of U.S. coastlines are eroding. Concurrently, the U.S. recycles less glass than other developed countries, landfilling hundreds of millions of tons every year. Recycled glass sand has many potential benefits over natural sand for combatting land loss; for example, it can be produced with controlled particle size to better resist erosion, making it an excellent—and underutilized—material for environmental restoration. ObjectivesThis research compares the physical and chemical properties of recycled glass sand to natural sands (beach and dredge) from the U.S. Gulf Coast to assess environmental safety. MethodsParticle size distribution, angularity, particle and bulk density, compaction, and permeability were evaluated using standard methods. Elemental composition and leaching were analyzed using x‐ray fluorescence and toxicity characteristic leaching procedure (TCLP), respectively. ResultsRecycled glass sand is not “sharp,” although it is less well‐rounded than natural sand. Porosity, compaction, and water permeability depend on particle size, and glass sand can be size‐separated to match or complement natural sand. Recycled glass sand is mostly silica. Additional elements used in glass processing are present at acceptable levels, and no leaching of harmful elements is detectable by TCLP. Thermally decomposable residues (e.g. label and adhesive) reliably comprised less than 1% of the material. ConclusionsThe characteristics of recycled glass sand make it a good resource for environmental restoration.
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- PAR ID:
- 10633610
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Restoration Ecology
- ISSN:
- 1061-2971
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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