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Nonpoint source (NPS) pollution is a severe problem in the U.S. and worldwide. Best management practices (BMPs) have been widely used to control stormwater and reduce NPS pollution. Previous research has shown that socio-economic factors affect households’ adoption of BMPs, but few studies have quantitatively analyzed the spatio-temporal dynamics of household BMP adoption under different socio-economic conditions. In this paper, diverse regression approaches (linear, LASSO, support vector, random forest) were used on the ten-year data of household BMP adoption in socio-economically diverse areas of Washington, D.C., to model BMP adoption behaviors. The model with the best performance (random forest regression, R2 = 0.67, PBIAS = 7.2) was used to simulate spatio-temporal patterns of household BMP adoption in two nearby watersheds (Watts Branch watershed between Washington, D.C., and Maryland; Watershed 263 in Baltimore), each of which are characterized by different socio-economic (population density, median household income, renter rate, average area per household, etc.) and physical attributes (total area, percentage of canopy in residential area, average distance to nearest BMPs, etc.). The BMP adoption rate was considerably higher at the Watts Branch watershed (14 BMPs per 1000 housing units) than at Watershed 263 (4 BMPs per 1000 housing units) due to distinct differences in the watershed characteristics (lower renter rate and poverty rate; higher median household income, education level, and canopy rate in residential areas). This research shows that adoption behavior tends to cluster in urban areas across socio-economic boundaries and that targeted, community-specific social interventions are needed to reach the NPS control goal.
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Systematic Review of Best Management Practice Implementation for Agricultural Phosphorus Management in Florida: A 30-Year Overview
BMPs have been proven to be efficient in managing P loads in Florida. BMP efficiencies vary between 20% and 80%, with few higher than 50%.Integration of modeling strategies and field demonstrations could improve BMP efficiencies. Further implementation of testbeds and pilot studies could improve adoption and enhance our understanding of BMP efficiency. In Florida, the implementation of best management practices (BMPs) has significantly reduced phosphorous (P) loads from the Everglades Agricultural Area (EAA) into the Lake Okeechobee watershed over the past two decades. While the removal of over 6,165 metric tons of total phosphorus entering the Everglades Protection Area is a notable achievement, some freshwater sources continue to exceed established limits (Naja et al., 2017), demanding a critical examination of BMP efficiency at managing low P concentrations. In this systematic literature review, we analyzed peer-reviewed journal manuscripts published over the past 30 years, focusing on the intersection of phosphorus management, water, Florida, and the environment. The dataset synthesized from our review provides insights into the efficiency of BMPs in terms of P management over time. Our findings show a predominant focus on stormwater treatment areas (STAs) and constructed wetlands as BMPs with demonstrated good efficiency. However, the variability in reported efficiencies underscores the complexity of phosphorus pollution and its impacts. Treatment trains ranged from 20% to 39% for the lower range of efficiency in phosphorus removal and from 60% to 79% for the higher range of efficiency. Focusing on strategies with higher P load reduction efficiencies could enhance future management strategies in Florida. Field-based pilot studies with well-defined control settings can facilitate long-term evaluations of P management programs that allow the implementation of BMPs. Similarly, the evaluation of new technologies, including materials, precision-smart practices, and the integration of modeling strategies with field-scale studies suggest a promising approach to engaging stakeholders in achieving higher BMP efficiencies. This systematic review highlights current BMP strategies that have demonstrated high P load reduction efficiency. There is a need for continued research that simultaneously assesses strategies to reduce P pollution before it forms and employs a multidimensional approach to P management. This approach should integrate multiple successful BMPs through field and modeling strategies. Keywords: Agriculture, Best Management Practices (BMP), Florida, Non-point source pollutants, Phosphorus loads.
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- Award ID(s):
- 2019435
- PAR ID:
- 10611712
- Publisher / Repository:
- ASABE
- Date Published:
- Journal Name:
- Journal of Natural Resources and Agricultural Ecosystems
- Volume:
- 2
- Issue:
- 3
- ISSN:
- 2835-2351
- Page Range / eLocation ID:
- 139 to 152
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.13031/jnrae.15912
