Few topics have penetrated national and global politics and science the way that climate change discussions have. Yet, despite international agreements to fight climate change, greenhouse gas emissions continue to increase and global temperatures continue to rise. The potential effects on our lives are drastic: recent wildfires in the U.S. and Australia, floods due to heavier precipitation, and heavy losses of crops are all indicative of this.
Far from being the villain in this scenario (especially livestock producers, who bear an unbalanced brunt of climate blame in public circles), the agriculture industry has tools and opportunities to improve the overall climate situation. In the U.S. alone, the Environmental Protection Agency says agriculture contributes to 10 percent of greenhouse gas emissions, far lower than other major sectors, such as electricity and transportation.
The CO2 that our world has released — and is continuing to release into the atmosphere — remains there indefinitely. Climate change will thus continue to worsen unless atmospheric carbon is removed. Therefore, finding cutting-edge solutions for the active removal of greenhouse gases is crucial.
A group of scientists from the U.S. and Israel have proposed a CO2 removal strategy that utilizes the powerful methods of synthetic and systems biology (SSB is characterized by the development and application of mathematical, computational, and synthetic modeling strategies in response to complex problems and challenges within the life sciences). The further development and deployment of SSB could enable the genetic modification of plants to remove CO2 from the atmosphere irreversibly. At a symposium held in Boston, the scientists discussed their ideas for mitigating the negative effects of climate change, with their findings published in BioDesign Research.
Professor Charles DeLisi of Boston University, lead author of this paper, explains this concept using an interesting analogy, “Engineers learned long ago how to design and manufacture circuits to perform desired tasks. In the past two decades, biomedical engineers have begun to learn to design and manipulate the circuitry that enables cells to carry out biological processes with enhanced functions: in this case, CO2 removal.”
In this paper, the scientists began by summarizing a few ways in which these bioengineered, sustainable plant phenotypes can be developed. They suggested targeting and modifying genes that, for instance, change the root-to-shoot ratio to increase the amount of CO2 trapped in the soil. Additionally, genetically altering leaf properties could potentially increase crop productivity: for example, a plant can be modified to process more energy via photosynthesis without needing as much sunlight, or they could become more drought-resistant via leaves that don’t allow as much water to evaporate. Improving crop productivity would increase sustainability because fewer crop failures and more yield means less land is needed to grow enough food.
That’s significant, because prior research has raised the concern that hyper-focusing on climate change can either risk revenue volatility for growers or cause a decrease in crop yields.
Other interesting genetic modifications of plants involve giving them the ability to “fix” nitrogen (converting nitrogen gas into forms that plants can use for growth). Currently, only legumes (beans) with nitrogen-fixing bacteria can do this, but if the ability can be added to major staple crops like wheat, we could draw large amounts of the “nitrous oxide,” a major greenhouse gas, out of the atmosphere. Besides plants, various bacteria could also be engineered to use CO2 as their carbon source instead of sugars, potentially becoming a space-saving way of pulling CO2 from the atmosphere.
While these methods are promising, DeLisi and his colleagues acknowledge that their proposals are a step into the unknown. “
Perturbations of the carbon cycle on a global scale will be profound and irreversible in their consequences. Developing a national agenda without a serious and open analysis of risks and mitigation strategies would be a mistake both politically and ethically.”
In particular, the scientists warn that applications of SSB require us to think carefully about how to prepare for unintended consequences, who is liable in case of harm, and whether benefits are fairly distributed in society. Having strong answers for these issues will help to generate public acceptance.