Like wind, solar, and other renewable energy sources, biomass can make a positive impact on our atmosphere by lessening our dependence on climate change-inducing fossil fuels. Biomass energy differs from other renewables, however, in the extent to which its use is directly tied to the farms, forests, and other ecosystems from which biomass feedstocks are obtained. Because of this close association, the use of biomass has the potential to result in a wide range of environmental and social impacts, both positive and negative, above and beyond its use as a substitute for fossil fuels. Impacts on soils, water resources, biodiversity, ecosystem function, and local communities will differ depending on what choices are made regarding what types of biomass are used, as well as where and how they are produced. This is why biomass needs to be produced and harvested as sustainably as possible. In this sense, sustainability refers to choosing management practices that minimize adverse impacts and complement local land-management objectives, such as farm preservation, forest stewardship, food production, and wildlife management.

One land use issue that often arises is the perceived conflict between food production and bioenergy (the so-called ‘food-vs.-fuel’ debate). Many traditional food crops, such as corn, sugar and vegetable oils, are also some of the most commonly used energy feedstocks. Furthermore, agricultural land may be shifted from producing food to the production of dedicated energy crops. The use of agricultural crops and lands has undoubtedly contributed in part to increased prices for many of these commodities. Many other factors, however, have contributed much more substantially to this increase, including inflation of the dollar and especially the rapid rise in price of fossil fuels. Oil and natural gas, in the form of fuel and synthetic fertilizers, are two of the biggest economic inputs in food production and distribution. There are many opportunities to further reduce the conflict between food and fuel production, including an increased use of agricultural wastes, logging residues, food scraps, municipal solid waste, and marginal lands.

Another issue heavily associated with biomass production is greenhouse gas emissions from land management and land use change. These refer to emissions of greenhouse gases (especially CO₂, CH₄, and N₂O) resulting from agricultural inputs, management practices, and land use changes associated with production of biomass. These emissions can be divided into direct and indirect sources. Direct emissions refer to those resulting from land clearing, agricultural inputs (such as fertilizers), or management practices undertaken in the process of growing or harvesting a biomass crop. Indirect emissions are associated with market-driven land use change. These are the emissions that occur when forests, grasslands, or other ecosystems are cleared to produce crops or other commodities to compensate for land that has been diverted to energy production. The effects are difficult to quantify or attribute, making indirect emissions from land use change (ILUC) a very controversial subject.

Finally, it is important to remember that biomass markets will add value to biomass products, residues, and productive lands. This value will help improve the economic viability of working lands and act as a positive incentive to help preserve farms and forests from the accelerating threat of urban and suburban sprawl – the greatest land use impact.

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