Grasslands play a pivotal role in mitigating drought and floods, cycling and moving nutrients, detoxifying and decomposing waste, controlling agricultural pests, maintaining biodiversity, generating and preserving soil and renewing their fertility, and contributing to climate stability.
A new study in Washington found that grasslands used by humans are related to the climate change over the last centuries. The study revealed that human activities in grasslands lead to greenhouse gas emissions.
Grasslands absorb and release carbon dioxide and emit methane from grazing livestock and nitrous oxide from soils. This happens especially when manure or mineral fertilizers are introduced into the soil. The study also found that methane and nitrous oxide increased due to emissions from livestock. The ability of grasslands to absorb more carbon and pack it in soil was estimated to have intensified over the last century.
Grasslands protect soil from wind and water erosion. They also provide high quality, relatively inexpensive feed for livestock and wildlife. They help maintain soil fertility because it encourages higher levels of soil organic matter than row crops.
Researchers also found that human activities have shifted the balance of greenhouse gas removals. The expansions of pasture land and higher livestock numbers have resulted in global grasslands accelerating climate warming. The mitigating role of grasslands will depend on aspects like future changes in grass-fed livestock numbers, stability of accumulated soil carbon in grasslands, etc.