Land covers 29% of the Earth's surface and supports human activities like agriculture. Large parts of land are uninhabitable due to factors like topography, climate, and forests/deserts. Land is classified based on physical factors like topography and climate as well as human factors like population and land use policies. In India, 30% of total land area is mountainous, 27% is plateaus, and 43% is plains. Soil conservation aims to prevent soil erosion and degradation through practices like crop rotation, cover crops, windbreaks, and runoff control.