Compost incorporation and wildflowers introduction for stormwater infiltration and erosion-control vegetation cover establishment in post-construction landscapes

• Published in: Journal of environmental management Vol. 369; p. 122324
• Main Authors: Islam, Md Mahfuz, McLaughlin, Richard A., Austin, Robert, Kranz, Christina N., Heitman, Joshua L.
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.10.2024
• Subjects: Compost; Composting - methods; Ecosystem; Poaceae - growth & development; Post-construction landscapes; Soil; Soil compaction; Soil Erosion; Soil restoration; Supervised image classification; Unmanned aerial vehicle; Compost; Supervised image classification; Unmanned aerial vehicle; Post-construction landscapes; Soil restoration; Soil compaction
• ISSN: 0301-4797; 1095-8630; 1095-8630
• DOI: 10.1016/j.jenvman.2024.122324

Urban and suburban development frequently disturbs and compacts soils, reducing infiltration rates and fertility, posing challenges for post-development vegetation establishment, and contributing to soil erosion. This study investigated the effectiveness of compost incorporation in enhancing stormwater infiltration and vegetation establishment in urban landscapes. Experimental treatments comprised a split-split plot design of vegetation mix (grass, wildflowers, and grass-wildflowers) as main plot, ground cover (hydro-mulch and excelsior) as subplot, and compost (30% Compost and No-Compost) as sub-subplot factors. Wildflower inclusion was motivated by their recognized ecological benefits, including aesthetics, pollinator habitat, and deep root systems. Vegetation cover was assessed using RGB (Red-Green-Blue) imagery and ArcGIS-based supervised image classification. Over a 24-month period, bulk density, infiltration rate, soil penetration resistance, vegetation cover, and root mass density were assessed. Results highlighted that Compost treatments consistently reduced bulk density by 19–24%, lowered soil penetration resistance to under 2 MPa at both field-capacity and water-stressed conditions, and increased infiltration rate by 2–3 times compared to No-Compost treatments. Vegetation cover assessment revealed rapid establishment with 30% compost and 60:40 grass-wildflower mix, persisting for an initial 12 months. Subsequently, all treatments exhibited similar vegetation coverage from 13 to 24 months, reaching 95–100% cover. Compost treatments had significantly higher root mass density within the top 15 cm than No-Compost, but compost addition did not alter the root profile beyond the 15 cm depth incorporation depth. The findings suggest that incorporating 30% compost and including a wildflower or grass-wildflower mix appears to be effective in enhancing stormwater infiltration and provides rapid erosion control vegetation cover establishment in post-construction landscapes. •Compost incorporation reduced bulk density and increased infiltration rates.•Wildflowers, grass, and wildflower grasses mixes had similar infiltration rates.•Rate of vegetation cover establishment was enhanced by compost and similar between vegetation types.•Compost enhanced root mass within depths of incorporation.