Location: Soil Management Research
Title: Can carbon in bioenergy crops mitigate global climate change? Author
Submitted to: Book Chapter
Publication Type: Book / Chapter
Publication Acceptance Date: March 26, 2013
Publication Date: N/A
Interpretive Summary: There is a growing recognition by the general public that the relationships between agriculture, food, feed, bioenergy, and climate change have to be better understood. This understanding is necessary in order to gain more realistic estimates of future bioenergy potentials and their role in mitigating climate change. Biomass, as a renewable energy source, has been considered as carbon-neutral. Its use as an energy source will not add to the atmosphere more carbon dioxide than what it takes. Energy from biomass has the largest impact on local communities in many parts of the world. Biomass energy has direct effects on rural livelihood and employment, food availability and accessibility, freshwater supplies, and lifestyle changes. Conventional grain and oilseed crops and their residues have been used as bioenergy sources. However, the production of bioenergy from these crops may impact food and feed production. Other crops are being developed as sources of biofuel, including perennial grasses, new oilseed crops, and trees that are more efficient than conventional grain or oilseed crops in producing biomass for bioenergy. The amount of biofuel that can be produced globally in an environmentally- and economically-responsible way is limited. Available land, adequate water and fertilizer supplies to grow bioenergy crops are major constraints. In addition, new management practices and technologies are needed to improve energy yield of the new bioenergy crops and to minimize their environmental impact. The information presented in this chapter provides a synthesis and comprehensive analysis of value to students, farmers, and the general public of how carbon captured by bioenergy crops and stored in soils can contribute to climate change mitigation.
Technical Abstract: Different forms of carbon cycle continuously through several pools in natural and managed ecosystems and spheres. Carbon’s recent "commodification," as a negative environmental externality, rendered it a "scarce" and "tradable" element. Although the carbon supply in nature is not limited, energy is required to make it available as a plant nutrient, assimilate it in plant tissues and sequester it as temporary or recalcitrant carbon in soils. Human demand for carbon-based energy and plant-fixed carbon accelerated and altered its global cycle, raised its atmospheric content, contributed to climate change through global warming and impacted several provisioning, regulating and supporting ecosystem services. Agroecosystems are both sources and sinks of carbon. In a carbon dioxide-constrained world, plant-fixed and sequestered carbon in natural and managed ecosystems has a potential role in mitigating climate change, providing carbon-neutral and renewable bioenergy, and positively affecting ecosystem services. Due to intricacies of the complex, interconnected biogeochemical cycles involving carbon, nitrogen and water in which soils play an important role; bioenergy crops do not provide an easy solution to climate change mitigation. This chapter presents a critical review assessing the state of knowledge, and exploring opportunities and challenges of the role of carbon in bioenergy crops in mitigating global climate change, while sustainably providing other ecosystem services.