Agronomic principles of cover crops:
Statement 1 is NOT true: In arid and semi-arid dryland farming, cover crops transpire significant amounts of water and directly deplete critical soil profile moisture reserves needed by the primary cash/food crop. Therefore, cover crops are unsuitable or hazardous for very dry areas unless rainfall is sufficient to recharge the root zone.
Statements 2, 3, and 4 accurately describe classic agronomic roles of cover crops (erosion protection during fallow periods, buffer strips against wind abrasion of tender seedlings).

Basic (steady-state) infiltration rates according to soil texture:
Sand / Coarse sand: \(\gt 20\text{ mm/h}\)\lt /strong\gt (typically 20 to 50+ mm/h due to large macropores). \lt strong\gt Loams\lt /strong\gt : \lt strong\gt \(5\text{ to }10\text{ mm/h}\)\lt /strong\gt (or up to 10-20 mm/h). \lt strong\gt Clayey soils\lt /strong\gt : \lt strong\gt \(1\text{ to }5\text{ mm/h}\)\lt /strong\gt (slow intake due to micropores). \lt strong\gt Sodic (alkali) clayey soils\lt /strong\gt : Characterized by extreme clay dispersion, aggregate collapse, and soil swelling, which completely seals the conducting pores. Their steady-state infiltration rate is extremely low—typically \lt strong\gt \(< 1\text{ mm/h}\) (or virtually impermeable), NEVER \(\gt 20\text{ mm/h}\)!

Precise hydrologic definitions of soil water movement:
Infiltration is strictly defined as the process of water entry into the soil through the soil-atmosphere interface/surface.
Percolation is the subsequent downward movement of water within and through unsaturated and saturated layers of the soil profile.
Seepage is the lateral or subsurface flow of water into or out of channels/reservoirs.