Complex sentence: Grassland degradation, also called vegetation or steppe degradation is a biotic disturbance in which grass struggles to grow or can no longer exist on a piece of land due to causes such as overgrazing, burrowing of small mammals, and climate change.
Split into simpler sentences: Grassland degradation, also called vegetation or steppe degradation is a biotic disturbance in which grass struggles to grow and can no longer exist on that piece of land. This unnatural process has many causes, among which are overgrazing, burrowing of small mammals, and climate change.