Greenhouse gases in atmosphere are driving climate change, but we can look to the ground below us in our efforts to fight it. The United Nations has designated December 5 as World Soil Day -- and 2015 as International Year of Soils. Here's how soil plays a role in climate change.
The majority of greenhouse gases in the atmosphere come from burning fossil fuels, but the next largest source of anthropogenic (human-caused) greenhouse gas emissions is land use change -- deforestation and land cultivation for food production. Nearly one-third of the globe's anthropogenic (human-caused) greenhouse gas emissions are the result of agriculture, from crop lands and grazing lands.
Healthy soils sequester carbon and methane and reduce greenhouse gases in the atmosphere. When we maintain the health of the soil, it acts as a carbon sink and helps us mitigate climate change. Carbon-rich soil also holds more water, making us more resilient to droughts.
Higher temperatures and extreme weather events as a result of climate change can be damaging to soil health -- causing erosion, reduced moisture, and a loss of nutrients.
There's a difference between soil and dirt. Think of soil as alive and dirt as dead; remove organic matter and microbes from soil and you're left with dirt.
Unsustainable cultivation of land and poorly managed soil from agriculture is causing land degradation. This releases carbon dioxide into the atmosphere, further contributing to climate change. It also threatens our food systems, so maintaining healthy soil is a win-win.
Here's the good news: Degraded soil can be restored by adopting conservation methods that increase the soil's organic matter.
Even better news: California has a Healthy Soils Initiative aimed at maintaining and restoring healthy soils -- to support plant growth and crop yields while also sequestering carbon in natural and working lands.