Environmental issues associated with bioenergy and bioproducts encompass feedstock production, collection, and transportation impacts; emissions, wastewater, and other wastes associated with the conversion of biomass resources into bioenergy and bioproducts; and emissions and waste production associated with the use of bioenergy and bioproducts.
Given that a significant portion of biomass feedstocks are land-based resources, their impact on land is a key issue in determining their environmental sustainability. Issues of interest include erosion and associated chemical and nutrient runoff; changes in soil organic matter; impacts on other nutrients such as nitrogen cycling; changes in moisture retaining capacity; changes in microbial and nematode populations; and changes in other miscellaneous factors that affect the long term health and productivity of soils. Other environmental impacts of interest associated with the production of biomass resources include wildlife diversity; the potential to serve as a reservoir for pests and diseases of other crops; the potential to become invasive; and the potential to spread incorporated genes to wild populations.
Environmental issues associated with the production and use of bioenergy and bioproducts include greenhouse gas emissions; emissions of compounds that form smog or are involved in acid rain formation; emission of particulates; and emission of other criteria pollutants regulated by the Environmental Protection Agency. Wastewater treatment is also an issue.
A whole life cycle assessment (LCA) approach can be used to examine several of these issues. An LCA is a cradle to grave evaluation of energy and environmental issues associated with producing, collecting, and transporting the biomass resource, converting the biomass into bioenergy or bioproducts, and distributing and using the bioenergy or bioproduct. The more sophisticated LCAs are beginning to evaluate soil nutrient cycling impacts associated with the production of crops and trees. LCAs frequently include an assessment of the petroleum derived product displaced as a means to compare the relative environmental impacts.