How did overgrazing threaten steppe ecosystems?

Overgrazing poses a significant threat to steppe ecosystems by causing severe damage to both soil and vegetation, often contributing to desertification and biodiversity loss.123

The primary impacts include:

• Soil Degradation: Livestock grazing can denude vast areas, exposing soil to baking and sealing. Trampling by herds destroys the plant roots that bind the soil together, which increases erosion and reduces the soil's ability to infiltrate water. This often leads to increased runoff and flooding.12
• Vegetation Decline: Animals may consume plants down to the ground, inhibiting growth by reducing the tissues available for photosynthesis. Furthermore, repeated trampling along paths to water sources compacts the soil, hindering root development.12
• Altered Plant Communities: Grazing pressure on preferred grasses gives a competitive advantage to inedible species, such as certain cacti or shrubs. These changes can be persistent, as the new plant communities may prevent native grasses from recolonizing the area.12

In Eurasia, intensive overgrazing has been a major driver of environmental modification, particularly in regions like Inner Mongolia, where it has led to drastic ecological changes.3