THE ROLE OF MICRO-CATCHMENTS IN REHABILITATION OF DEGRADED LAND IN ARID AND SEMI ARID LANDS

Abstract

Land  degradation  as  a  result  of  unsustainable  human  activities  and  climatic  variations  is  a  serious  problem undermining  the  productivity  of  arid  and semi-arid  lands  (ASALs).  Large  portion  of  these  lands  are  being threatened  with  desertification.   This  paper  is  aimed  at  identifying  the  significance  of  Micro-catchment  water harvesting (MCWH) technique in reclaiming degraded lands by reviewing various researches done in the area. The central point of MCWH technique is to facilitate the storage of water in the soil for plants use which may otherwise be lost to runoff. MCWH technique is discovered to work well in controlling degradation for its effectiveness in reducing  soil  and  nutrients  movement.  It  exhibits  low  conveyance  losses  and  considerable  leaching  capacity, prevents  moisture evaporation, and can be constructed  on almost any slope  with little construction cost. Plants survival rate was discovered to increase tremendously under normal rainfall condition when micro-catchments are used. Even though the technique appears to be successful in different areas implemented for both crops and trees cultivation,  it  has  not  been  very  popular  among  farmers  and  environmental  agencies  in  ASALs.  This  can  be associated  with  the  perception  of  the  initial  intensive labor  requirement,  and  low  crop  density  compared  to traditional irrigation methods. With adequate awareness programs and financial interventions, a wider adaptation of MCWH technique can help in vegetation of the degraded lands in ASALs.

Key words: Arid and semi-arid lands, land degradation, micro-catchment, reclamation, water harvesting, erosionList of abbreviations