Thursday, August 7, 2008

PS 53-10: Multifunctionality of tree habitats on farms: Evidence from Vermont

Sarah Taylor Lovell, V. Ernesto Mendez, Daniel L. Erickson, Chloe A. Nathan, and S'ra DeSantis. University of Vermont

Background/Question/Methods

Agroecosystems can play a key role in landscape multifunctionality when diverse habitats, particularly those with tree cover, are conserved on farms.  Treed habitats including woodlots, riparian buffers, windbreaks, wetlands, and agroforestry patches have great potential to reduce runoff, infiltrate storm water, conserve biodiversity, and increase landscape heterogeneity in agricultural landscapes.  Additionally, recent studies suggest treed habitats contribute to cultural functions (visual quality, recreational) and alternative production functions (edible fruit/nuts, timber, firewood, etc.) in rural areas.  In this study, we investigated functions of on-farm treed habitats for Vermont farmers in the Lamoille watershed of the Lake Champlain Basin.  The site was selected because the land use pattern is representative of the region, containing a mixture of agriculture and forest in different habitat types.  This watershed also contains a large number of diversified farms that might benefit from on-farm treed habitats.  An initial spatial analysis was conducted in Geographic Information Systems (GIS) to characterize the relationship between forest, agriculture, and hydrological land cover classes. 

Results/Conclusions

We found that while the percentage of agricultural land is relatively low within the entire watershed (18% of the land base), much of the farming occurred in the river valley, in close proximity to sensitive hydrologic features.  In those areas, agriculture comprised 28%, 34%, and 50% of the land cover within 1000 m, 500 m, and 100 m buffer zones, respectively, when adjusted for terrestrial land area (with water and wetland areas removed).  This finding suggests that critical trade-offs may exist between agricultural production and water quality functions of riparian buffer zones in these areas.  Through semi-structured interviews with diversified farmers in the Lamoille watershed, we explored existing and potential future functions of treed habitats for protecting water quality on farms adjacent to rivers or streams.  We also investigated the role of trees in supporting farmer livelihoods through production functions or governmental conservation incentives programs.  We found that farmers benefited from alternative forest products, both for direct consumption and sale, including firewood, timber, maple sugar, edible fruits and nuts, and wood crafts.  Additionally, farmers indicated cultural benefits from treed habitats: visual quality, spirituality, and recreation.  From these results, we can begin to identify the types of treed habitats that have the greatest potential for contributing to the conservation of ecosystem services in agricultural landscapes, so that farmers might incorporate these into the design of the farm to leverage compensation for best management practices.