greenhorns can stop climate change
Regenerative Agriculture can Mitigate Climate Change
By Eliav Bitan.
We greenhorns are the first generation to farm in a climate that has been radically changed by hundreds of years of burning carbon based fossil fuels. This week at the Quivera Coalition conference in Alburqurque, New Mexico we learned more about how the way we farm is actually the best and most readily available technology for capturing and storing atmospheric carbon dioxide. In addition to climate stabilization, agricultural carbon sequestration prevents erosion, improves food quality, and increases yields in dry and wet years. By adopting practices that build carbon in soil, we can benefit our farms local communities, because these practices make more water and food on our farms.
Some have said that only way farmers can store carbon their soils is through no-till farming that relies on herbicides. Reducing tillage provides benefits for soil structure and water management. But recent soil carbon measurements have led to an emerging scientific consensus that herbicide dependent no-till can increase surface soil carbon, but deplete deep soil carbon. In addition, production of toxic herbicides emits greenhouse gases and they harm local wildlife and water.
Data from around the world offers hope for climate change mitigation. Farming using cover crops, rotation of crops, rotating pastures through arable land, perennial crops and organic soil amendments regenerates soil and stores carbon. Soil rich in carbon holds water more effectively, making farmers more resilient as our climate change. For example, cover cropping increases the portion of the year that photosynthesis happens. It also feeds carbon-holding fungi in the soil. A year of cover cropping can store about 1 metric ton of carbon per acre. This translates to about 3 metric tons of CO2 per acre. Composting not only avoids the decomposition of organic matter into the atmosphere, it also feeds friendly soil fungi that store carbon. Experiments have found compost storing around 2-3 metric tons of carbon per acre, or about 6-7 metric tons of carbon dioxide. Data from USDA in Maryland, and around the world confirms the possibilities of these levels of carbon sequestration.
The latest research shows that farmers can store far more carbon in soils than anyone previously thought possible. Farmers deserve credit for this contribution to stopping climate change. With 42% of farmers poised to retire, and demand higher than ever for local and sustainable food, we need more farmers and ranchers! Policies in the United Nations, European Union, New Zealand, and Canada, already credit farmers for soil carbon. If CO2 is valued around $30 per ton by a carbon market or carbon payment program, farmers could earn over $100 per acre. Grocery stores and retailers are seeking to find "carbon friendly" products for their customers. These new market opportunities can help draw new young farmers into agriculture, and enable them to take part in solving contemporary challenges. If policies give larger rewards to farmers who provide greater results, we will have more incentive to build carbon, and could slow down climate change. To make this happen, soil carbon measurement should be widely adopted. Measurement technology should be made cheaper, and more accessible to farmers. For agriculture to be part of the solution to climate crisis, we should pay farmers for storing carbon.
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- Veris Corporation, for example, has reported measurement costs as low as $5 per hectare per year with 90% confidence.