Add to ORKGNot AvailableThe present investigation characterizes different forms of soil acidity in surface soils along an altitudinal sequence of Nagaland state of India and their relationship with soil properties. One hundred surface soil samples were collected from four distinct landforms viz., highly dissected high hills (>2000 m above mean sea level, MSL) with very steep slopes (>33%) (HDHH), medium and lower hill ranges (1000-2000 m above MSL) with steep slopes (15-33%) (MLH), moderately dissected piedmonts (500-1000 m above MSL) with moderately steep slopes (10-15%) (MDP) and inter-hill valleys (<500 m above MSL) with gentle slopes (3-5%) (IHV). The soils had dominance of pH dependent acidity followed by exchangeable acidity in all the la...