Bioenergy

Environment

FAO/CH. Errath

Bioenergy production affects the environment at local and global levels, impacting land and water resources, biodiversity and the global climate. Although there are environmental impacts throughout the production chain - feedstock production, conversion and use - most impacts occur in the feedstock production stage and mirror those related to agricultural production in general.

Climate change mitigation
Mitigation of climate change is a policy goal of bioenergy development in many countries. However, life-cycle analyses that measure emissions throughout the bioenergy production chain indicate a wide divergence in carbon balances according to technologies used, locations and production systems - with some even leading to greater emissions than fossil fuels.

Key sources of greenhouse gas (GHG) emissions are:
- land conversion;
- mechanization;
- fertilizer and pesticide use at the feedstock production stage and
- use of non-renewable energy in processing and transport.

Systems that use organic waste and residues from agriculture, forestry and/or urban and industrial organic waste, or perennial energy plants on degraded land, offer higher potential GHG emission savings.

The impact of land-use change, an aspect of particular importance regarding carbon balance and biodiversity conservation, remains difficult to estimate particularly as concerns effects from indirect land use change. When land with high carbon content, such as forest or peat land, is converted to grow biofuels, the immediate resulting carbon balance is inevitably negative, with conversion creating "carbon debts" that could take decades or even centuries to "repay". In addition, a comprehensive carbon balance assessment must take into account "indirect" land-use change which refers to emissions from land that has been put into agricultural production, because other agricultural land has been converted to bioenergy crops, or because of increased demand for food crops as a result of bioenergy cropping. Such indirect effects are difficult to attribute and measure.

The extent of land-use change caused by bioenergy growth depends upon several factors:
- land tenure security;
- integration between food and energy production systems and
- potential for intensification.

Some further yield improvements on existing land are possible in response to rising prices, in particular through increased input use and improved management practices. However, improved bioenergy feedstock technologies are still in the development stage so, in the short run, the lion's share of increased production is likely to come from area expansion.
 
Biodiversity
When areas such as natural forests or other biodiversity rich ecosystems are converted for feedstock production, the loss of biodiversity is likely to be significant, even if land expansion is temporary. A further concern lies in the possible introduction of invasive species for biofuel production. Agricultural biodiversity could be affected by large-scale mono-cropping practices and the introduction of genetically modified materials.
 
Water and soil
FAO/A. ContiMany feedstocks - including sugar, palm oil and maize - are highly water intensive: their expansion is likely to create even greater competition for this already scarce resource, depending upon location and production methods. Liquid biofuel crops already account for approximately 1% of water transpired by crops and 2% of irrigation water. Intensive feedstock production also affects downstream water quality through run-off of fertilizers and agrochemicals, and soil erosion. The impact of feedstock production on soil erosion depends critically on the farming techniques that are employed, in particular on tillage practices, the level of soil cover and crop rotations. Where perennial bioenergy feedstocks replace annual crops, the permanent cover and root formation will help improve soil management and reduce soil erosion.
 
Good Agricultural Practices
The adoption of good agricultural practices, such as integrated pest and soil management, no or minimum tillage, retention of soil cover, multiple cropping, appropriate crop choice and crop rotations, can mitigate negative environmental impacts of bioenergy production, in particular those related to carbon, soil and water resources. The use of these practices also can reduce the threat to biodiversity, particularly soil biodiversity, through the retention of crop residues and diversified crop rotations. Wildlife habitats can be enhanced by introducing landscape management approaches in agricultural areas and retaining ecological corridors, as well as by careful and sustainable use of high-biodiversity biomass sources, such as grasslands, as feedstocks. Furthermore, non-food cropping systems could enrich agro-biodiversity. Promoting integrated local food-energy production systems, by combining feedstock production with crop production and feeding livestock on biomass not used for energy production or soil cover, can avoid waste and increase the overall system productivity for food and energy.

FAO's Work

FAO’s work on bioenergy and environment happens at many levels and places as traditional databases and maps are being amended or refined to accommodate the new evaluation and decision making needs.

The cross-sectoral environmental programme is aiming to support the process of informed decision making in the complex interactions of bioenergy development, climate change, and food, energy and environmental security through the following type of activities:

Simplification and Analytical Tools
For instance, within the BIAS project (Bioenergy Impact Assessment) bioenergy-environment interactions will be pulled together under the analytical framework aimed at simplifying their understanding and applications for decision makers and practitioners. Eventually it will lead to nationally and locally owned tools that benefit from the many experiences gathered and shared through this process.

Generation of Data and Knowledge Tools
Applications related to the BIAS project are supported by the generation and collection of the necessary data and the development of additional analytical tools. Many activities are connected to existing databases and mapping programmes.

Awareness Raising and Capacity Building
The country specificity of much of the needed information requires the active participation of interested FAO member countries. Building the necessary capacities and awareness to use and support data and knowledge management and further adapt analytical tool, is essential to create useful tools to support better governance and create sustainability.

Partnerships and Collaboration
The significant needs and resulting tasks related to the activities described above require many partners, more resources and more collaboration and coordination. FAO will be an active player in increasing knowledge, knowledge access, transparency and governance of the whole process.