Grasslands and Carbon Sequestration
Grasslands are an important part of California’s beautiful and diverse landscapes. Our sweeping hillsides are shades of green during the winter and swaying fields of golden grasses in the summer. Our grasslands provide many ecosystem benefits which contribute to the health of our planet. Some of the many benefits that grasslands provide are food for humans and animals, habitat for many birds, insects and animals, filtering and storing water, erosion control, and sequestering of carbon. Also, since native grasses can remain green even in the fall when it’s hot and dry, they offer a longer forage season for livestock and wildlife.
Grasslands can sequester large amounts of carbon due to their long root systems. Perennial grasses (those that last for years as opposed to annuals) can renew 50% of their root mass each year which means carbon is stored underground rather than being released back into the atmosphere. Grasslands actually remove more carbon from the atmosphere than any other ecosystem in our country. A study from UC Davis (Dass et al, 2018) found that grasslands are now more resilient carbon sinks than California’s forests because grasslands are less impacted by drought, rising temperatures and wildfires than our forests are.
Unfortunately, our grasslands are one of the most endangered ecosystems in the United States. California’s grasslands were formerly comprised of native perennial grasses. Once non-native settlers started arriving, so did exotic annual grasses which rapidly took over. Overgrazed rangelands, urbanization and the suppression of fire led to a decline in native grasses over the last two centuries. Only a very small percentage of the state’s native perennial grasses now remain. According to California Native Grasslands Association, restoration and preservation of our native grasses are needed to help negate the effects of climate change.
Agricultural and rangeland management practices can help mimic what naturally occurred on the landscape such as short duration, high intensity rotational grazing, and controlled burns, as stated in the 1992 journal Fremontia from the California Native Plant Society. This helps with the removal of litter, recycles nutrients and reduces seedbanks of competitive annual plants. The Marin Carbon Project has been working on restoring the health of rangelands through a process referred to as carbon farming. It is designed to maximize agriculture’s potential for moving excess greenhouses gasses from the atmosphere and storing them in the soil and vegetation, which can help build fertility, productivity and resilience.
Other organizations such as the Carbon Cycle Institute, local Resource Conservation Districts, county Land Trusts, Sonoma County Agricultural Preservation and Open Space District, and California Native Grass Association have also provided guidance on restoring our native grasslands and are also working on ways to reverse global climate change by promoting environmental stewardship.
Since grasslands provide so many benefits to humans, wildlife and the earth, they are certainly worth preserving and restoring. One step we can take in addressing climate change is to plant native perennials in our yards, schools and communities, or volunteer with restoration projects. Together we can help sequester carbon and preserve this important ecosystem.