A New Modeling Approach To Prioritize Riparian Restoration To Reduce Sediment Loading in Two Virginia River Basins

Abstract

Human impact, particularly land cover changes (e.g., agriculture, construction) increase erosion and sediment loading into streams. Benthic species are negatively affected by silt deposition that coats and embeds stream substrate. Given that riparian buffers are effective sediment filters, riparian restoration is increasingly implemented by conservation groups to protect stream habitats. Limited funding and a multitude of impaired streams warrant the need for cost-effective prioritization of potential restoration actions. We created a decision-support framework for conservation agencies and aquatic resource managers to prioritize riparian restoration efforts. Our framework integrates GIS data and field surveys into a statistical model to predict instream silt from estimates of upland soil loss and riparian filtration capacity. We focus specifically on prioritizing sites in upper sections of the Roanoke and Nottoway river basins (Virginia, US) based on observed records of Roanoke logperch (Percina rex), an imperiled sediment-sensitive species. Our statistical approach examines soil characteristics, land cover, precipitation, topography, and annual soil loss estimates from the empirically derived Revised Universal Soil Loss Equation, combined with land cover-based riparian filtration capacity as potential stream habitat predictors. We found riparian filtration capacity to be a significant predictor of silt cover, while precipitation was a significant predictor of embeddedness. Spatial scale was also a factor, in that spatial variance in silt cover and embeddedness was more accurately predicted at smaller spatial extents. Ultimately, our model can be used as a prioritization tool for mitigating high siltation areas, or for protecting low soil erosion areas.

Ecological and Environmental Benefits of Planting Green Manure in Paddy Fields

“…Lowlatitude rice fields are susceptible to water erosion caused by heavy rainfall during the winter season, and green manure varieties with a well-developed root system should be selected to protect the soil from nutrient loss in the topsoil. In addition, green manure acts as a good filter for both root microorganisms and leachable nutrients, and for the fertilizer and symbiotic organisms added to the topsoil [17]. The effects of green manure on crop growth and nutrient utilization are related to the improvement in soil physical and chemical properties, including soil bulk density, water conductivity, and carbon and nitrogen levels [18].…”

Social benefits of river restoration from ecosystem services perspective: A systematic review

“…Where global-scale river restoration research primarily analysed the overall environmental impacts and effects of urban hydro-systems (Wantzen et al, 2019) and the strategies to restore freshwater ecosystems from salinisation (Schuler et al, 2019), national scale studies focused on national policies involving government, experts, industry and local stakeholders, from small water bodies (Riley et al, 2018) to large river sanctuaries (Islam et al, 2018). Regional-scale studies were focused on specific decision-making frameworks (Zhang et al, 2019) such as predicting instream siltation (Scott et al, 2018), or channel rehabilitation (Tedford and Ellison, 2018) to improve water quality and aquatic biome to help understand ecological security in a watershed (Li et al, 2018). Local-scale studies primarily emphasized on willingness of local people towards payment for restoration (Khan et al, 2019) or identification of ES and their values (Foran et.…”

Calidad de los bosques ribereños y perspectivas de restauración en un río de la Patagonia Andina, Argentina

“…A pesar de la importancia de los ecosistemas ribereños y de los cursos de agua que le dan origen, estos ambientes están entre los paisajes más degradados por la acción del ser humano (Dudgeon et al 2006;Scott et al 2018). Además de la expansión urbana, en la Patagonia se desarrollan distintas actividades (e.g., extracción forestal, agricultura, ganadería extensiva e intensiva, plantaciones con coníferas exóticas) que de manera directa o indirecta afectan la integridad ecológica de los sistemas acuáticos (Miserendino et al 2008(Miserendino et al , 2011Kutschker et al 2009).…”

“…A lo ya descripto se suma la dificultad que existe en la Argentina respecto a la interpretación y demarcación en terreno de la línea de ribera (Maurín 2014), con las consecuentes implicancias que esto tiene en el uso y la conservación de los ambientes ribereños. En la actualidad, en varios países se llevan adelante estudios orientados a restaurar aquellos corredores ribereños afectados por los diversos usos de la tierra (Meli 2013;Boudell et al 2015;Scott et al 2018). Existen diferentes formas de manejo en estos ecosistemas (e.g., rehabilitación, revegetación, regeneración, restauración), tendientes a recuperar los procesos fluviales, incrementar la resiliencia del ecosistema acuático, establecer un sistema compatible con el uso de la tierra o recuperar el paisaje natural (Valero et al 2014).…”