Why were nomadic populations usually less dense than agricultural populations?

Nomadic populations on the Eurasian Steppe remained significantly less dense than agricultural populations primarily due to the ecological and logistical requirements of the pastoral way of life.1

The fundamental constraints include:

• Resource Management: Pastoralism requires maintaining an ecological balance between grazing conditions and animal herds. Because herds must move frequently to find fresh pasture, only small groups could efficiently manage flocks. Large concentrations of people and animals made daily travel between pastures prohibitively long for lactating animals, necessitating the dispersal of pastoralists into small kinship groups for most of the year.1
• Land Productivity: The vast expanse of the steppe could support only a limited number of humans because the primary food source—livestock—requires extensive grazing land rather than the intensive cultivation possible in settled farming societies.12
• Mobility and Materiality: Nomads relied on portable goods, as they could not maintain the permanent, heavy infrastructure associated with settled urbanization or intensive agriculture.31

While nomadic groups occasionally appeared as large "hordes" during raids, these were often temporary gatherings of followers from distant areas rather than a reflection of high regional population density.1