Discuss the natural and anthropogenic factors behind incidents of land subsidence. Suggest counter measures to contain such incidents.

Land subsidence is the phenomena where the ground underneath subs due to various reasons causing damage to overground infrastructure. By example Land subsidence in Joshimath. Factors behind land subsidence: (A) Natural Factors: a) Unustainable ground - as ground may be formed on unconsolidated sediments b) Instability caused due to seismic events (B) Anthropogenic factors: a) Ground water extraction beyond limit b) Underground mining extensively may also cause subsidence c) Rapid infrastructure building on unsafe

ground. Humor induced unstability - constructing roads. Counter measures needed: (1) Vulnerability mapping of land subsidence prone areas - on live historical satellite data (2) Stabilization measures: a) Injecting ground water b) Structural stability via Cement structures (3) Reduce infrastructure development in and around the expected area (4) Landslide walls to prevent any large scale landslides. Coupling R&D and institutional measures in dealing subsidence is needed to effectively deal with the problem