Two-way water conservation optimizes reclamation and crop production in a black alkali soil under rainfed conditions

摘要

The black alkali soils are generally characterized by poor hydraulic conductivity, high bulk density, highly dispersible and have low potentials. Survival of crop in such soils is normally not feasible either due to water stress or temporary waterlogging, crop growth suffers heavily on both the accounts. The reclamation with the help of chemical amendments need ample of water for efficient chemical reactions and leaching process. These soils are normally found in low rainfall areas having poor irrigation facilities. After adopting all the recommended management practices and necessary techniques, the effective depth of reclamation remains a limiting factor. Under such abnormal situations, no farmer can think about rehabilitation of such typical black alkali soils for crop production. But, it is well-established proverb that every cloud has a silver tinning and sometime a curse becomes boon for the other reasons, the only thing is to search this breakthrough. Several workers have reported that these soils have almost negligible infiltration when soil ESP approaches to >35 due to dispersion of fine soil particles and clogging of micro-pores. Thus the soil can work, as impervious sheet and may prove good for storing of surface run-off during rains.In-situ and ex-situ rain water harvesting technique can provide sufficient tool for reclamation of such soils and a proper way for management of our natural resource. Water retained in-situ will provide sufficient and justified amount of water for cropuse and reclamation without damaging, while ex-situ stored water is to be used only under stress conditions to optimize crop production.