Growth performance of some important tree species under arid conditions

摘要

In our country out of the total geographical area of 328.9 m ha. about 143 m ha is degraded and unfit for raising crops or supporting very poor crop yields due to one reason or the other. The major causes of this degradation are soil and water erosion, deforestation, water logging, salinity and excess biotic interference. The degradation of these areas is further accelerated as a result of increase in human and animal population. Land degradation scenario is grim particularly in arid regions doe tovery low and erratic rainfall (that too in a few rainy days), harsh climatic conditions, poor soil fertility status and heavy cattle population. As a result very few crops are able to grow with very poor productivity/yield. However, to meet the demand oflarge human and cattle population for food, fodder, fuel wood, medicines & timber, the presently available land and forest resources are being over exploited leading to further degradation.