If you use grasslands for grazing cattle you get meat, or also wool with sheep. Sequestering carbon into grassland soil (or into any soil, really) makes them better at absorbing and retaining rainwater, reducing the risks of catastrophic floods in the watershed area.

You can make paper products including things like cardboard and packaging.

You can put livestock on it and produce meat.

Or if you just want to sequester carbon, you can harvest it and bury it deep in the ground.