Patil, V. D.Malode, Kailash Rameshrao2018-06-082018-06-082013-12-20T07056http://krishikosh.egranth.ac.in/handle/1/5810050075The present investigation “Organic carbon mapping of Agro-ecological zones of Marathwada region of Maharashtra state” was carried out during 2009 to 2012 .A comprehensive study encompassing 22 soil profiles (Identified soils series) and 330 surface soil samples were evaluated for various soil properties. The soil samples collected during profile studies and surface soil samples were analyzed for various physical and chemical properties and soil carbon parameters. From the data, carbon to nutrient ratio was calculated and results are presented in previous chapter. Further from the analyzed data the soil organic carbon maps are generated and presented. The soil site suitability of important crops of region was also judged. It was aimed to study the organic carbon content in varied soil series and surface soils of agro ecological regions of Marathwada. To evaluate the physical and chemical properties and dynamics of nutrient status of soils of Marathwada region to find out relationship between C:N, C:P, and C;S ratio and soil properties under varied agro ecological regions of Marathwada.to prepare maps of soil organic carbon status and to study the cropping pattern and land use of agro ecological region of Marathwada. The results showed that the soils of Marathawada region are very shallow to very deep, clayey, sub angular blocky, very dark gray brown to black. Taxonomicaliy these are Lithic Ustrorthents, Typic Ustrothrents, Vertic Ustochrepts and Typic Haplusterts. The soils are slight to moderately alkaline, safe in total soluble salt concentration and calcareous in nature. These parameters found to be increased with depth of soil.The Entisols, Inceptisols and Vertisols showed variation in fertility status. In general the majority soil samples were categorized as low in N and P, high in Potassium and sufficient in Ca and Mg. Irrespective of soil type the higher organic carbon content, SMBC and CO2 was observed in transiently high rainfall zone than Drought prone and assured rainfall zone. The total carbon was higher in Drought prone zone (due to high CaCOa content). The higher C:N, C:P and C:S ratio was found in Drought prone zone .In Vertisols higher carbon content was observed in Drought prone zone. However, higher SMBC was recorded in Assured rainfall zoneJn Marathawada region organic carbon deficiency found to be spread over 46 to 67 % and showed less than 0.5 % organic carbon. The intensively cropped area (two to three crops in a year) had more spread of organic carbon deficiency than single cropped area.The correlation coefficients values computed for various soil properties in relation to organic parameters showed that pH, EC and CaCOa had negative correlation with various soil carbon parameters.The pedons of Typic Ustorthents were not found suitable for soybean and pigeon pea. Typic Haplusterts found to be highly suitable for pigeon pea. Further Typic Ustorthents were not suitable for cotton cultivation. Vertic Ustochrept were moderately suitable for soybean and cotton and Typic Hapluserts were highly suitable for cotton.ennullThesis