A Watershed-scale Assessment of Cost-Effectiveness of Sediment Abatement with Flow Diversion Terraces
- Qi Yanga,
- Zhengyong Zhaoa,
- Glenn Benoyb,
- Thien Lien Chowc,
- Herb W. Reesc,
- Charles P.-A. Bourquea and
- Fan-Rui Meng *a
- a Faculty of Forestry and Environmental Management, Univ. of New Brunswick, 28 Dineen Dr., Fredericton, NB, E3B 6C2, Canada
b Environment Canada and Agriculture & Agri-Food Canada, Potato Research Centre, 850 Lincoln Rd., Fredericton, NB, E3B 4Z7, Canada
c Potato Research Centre, Agriculture and Agri-Food Canada, 850 Lincoln Rd., Fredericton, NB, E3B 4Z7, Canada
Soil conservation beneficial management practices (BMPs) are effective at controlling soil loss from farmlands and minimizing water pollution in agricultural watersheds. However, costs associated with implementing and maintaining these practices are high and often deter farmers from using them. Consequently, it is necessary to conduct cost-benefit analysis of BMP implementation to assist decision-makers with planning to provide the greatest level of environmental protection with limited resources and funding. The Soil and Water Assessment Tool (SWAT) was used to evaluate the efficacy of flow diversion terraces (FDT) in abating sediment yield at the outlet of Black Brook Watershed (BBW), northwestern New Brunswick. Different FDT-implementation scenarios were expressed as the ratio of land area protected by FDT to the total cultivated area. From this analysis, we found that average annual sediment yield decreased exponentially with increased FDT protection. When the proportion of FDT-protected areas was low, sediment reductions caused by FDT increased sharply with increasing use of FDT. Similarly, marginal sediment yield abatement costs (dollar per tonne of sediment reduction) increased exponentially with increasing proportion of FDT-protected area. The results indicated that increasing land protection with FDT from 6 to 50% would result in a reduction of about 2.1 tonne ha−1 yr−1 and costs of sediment reduction increased from $7 to $12 per tonne. Increasing FDT-protected cropland from 50 to 100%, a reduction of about 0.9 tonne of sediment ha−1 yr−1 would occur and the costs would increase from $12 to $53 per tonne of sediment yield reduction.Please view the pdf by using the Full Text (PDF) link under 'View' to the left.
Copyright © 2010.