Using geographic information systems to assess potential biofuel crop production on urban marginal lands

To meet rising energy demands in a sustainable manner, the United States Renewable Fuel Standard 2 (RFS2) mandates the production of 3.78 billion L (1 billion gallons) of biomass-based biodiesel per year by 2020. Urban marginal lands, herein defined as lots with poor agricultural potential and unfit for residential purposes, can be used to cultivate biodiesel feedstock, which can contribute toward the RFS2. GIS is particularly well suited to identify the amount and location of these urban marginal lands. Biofuel crop production is one way for urban neighborhoods to reclaim vacant, blighted properties and also generate green energy for consumption.Combining soil classification data with urban development data, a GIS framework was developed to determine the amount of urban marginal land available in Pittsburgh, Pennsylvania. This location was chosen because small-scale sunflower crops are already being grown on urban marginal lands for biodiesel production. This paper evaluates two methods for identifying marginal lands for biofuel cultivation. The first is based on NRCS soil classifications derived from previous literature approaches. When compared with the locations of a nonprofit that is actually cultivating marginal lands, the NRCS soil classification method captures less than 35% of the marginal lands being cultivated in Pittsburgh, and 2400 ha (6000 acres) of marginal land in total that could be used to grow sunflowers for biodiesel production. We modify the NRCS marginal soil classification method to include certain types of urban commercial lands and lands not currently classified as marginal, and create a framework that identifies almost 90% of the marginal lands currently under cultivation in Pittsburgh, with approximately 3500 ha (8700 acres) of available marginal lands. Pittsburgh’s marginal lands could be used to produce up to 129,000 L (34,100 gallons) of sunflower-based biodiesel. This could contribute a maximum of 0.1% to Pennsylvania’s biofuel mandate and 0.003% to the RFS2. While a city’s individual contribution may be incremental on the national scale, multiple cities and regions may be able to contribute to the RFS2. In addition, there is an unquantified social benefit that results from community engagement and revitalization, which is part of the mission of the Pittsburgh nonprofit.

► This work develops a GIS framework for identifying urban marginal lands.
► The proposed framework identifies 3500 ha of unused urban marginal land in Pittsburgh.
► This marginal land could produce 129,000 L per year of sunflower biodiesel.
► Pittsburgh could contribute 0.003% to the RFS2 and 0.1% to Pennsylvania’s biodiesel mandate.
► Cities can follow Pittsburgh’s model to contribute to the RFS2 and state mandates.