Soil quality and fibrous mineral in black soils of Maharashtra

There are many reports on soil parameters that have both yield-reducing and yield-favouring potential. However, only a few are available on the index soil properties of fibrous minerals containing soils on crop yields in the semi-arid tropical (SAT) regions. These minerals in soils are mostly palygorskite and sepiolite. In the present study, only the palygorskite mineral in black soils (cracking clay soils), its formation and probable influence on soil quality is addressed. The present study was also undertaken to indicate a possible genesis of palygorskite in Indian black soils with and without soil modifiers (Ca-zeolites and gypsum) supporting both rainfed and irrigated agriculture in SAT environments. Palygorskite is absent in aridic/gypsic/sodic intergrades of black soils (Haplusterts), which might indicate non-interference of soil modifiers in its formation. Palygorskite is present only in sodic black soils (Calciusterts) in Maharashtra and parts of central and western India that contain no soil modifiers, and are under both rainfed and irrigated agricultural systems. The severe impairment of hydraulic properties of palygorskite containing naturally degraded black soils warrants a new research initiative for soils containing fibrous minerals.