INTRODUCTION At present, the greatest challenge before Indian agriculture is to boost food production and productivity as well as sustainability of agriculture as a whole (FAO 2017). There are some problems that inflict limits on these goals which raise serious concerns on national food security. These include deterioration of soil fertility, increase in cost of production, and low diversity of production systems (Gomiero, 2016). However, the need for improved crop productivity is more now than ever because of the increasing population and the consequent pressures from competing demands for land over time. Management of the fertility of Indian soils demands its build up of Soil fertility to enhance the capacity of a soil to supply essential nutrients to produce adequate food to feed the rapidly increasing population. Proper management of soil fertility mainly stress on careful identification of constraints of current deficiency status of nutrients and monitoring of changes in soil fertility to predict its deficiency. These deficiencies need to be alleviated through sound and proven practices of nutrients, water, crops and energy to soil management, so as to sustain food production at a reasonable level to ensure continual enhanced productivity in the future. Thus management of soil fertility vis-à-vis nutrient management at optimum level is one of the key factors in achieving high and sustainable productivity. Soil quality can be assessed by using remote sensing and GIS to generating maps of large areas helps in soil resources management and preventing soil degradation by using them optimally (Abdel Rahman et al., 2017). MATERIAL AND METHODS Study area. The erstwhile Karimnagar district is located under Northern Telangana zone lies approximately between the latitudes 17° 50' and 19° 05' N and longitudes 78° 29' and 80° 22' E. Karimnagar district is bordered by Nizamabad district in the West, Madhya Pradesh State in the east, Adilabad district in the North,Warangal and Medak districts in the South. The general elevation is 280 m MSL. This district is forms a part of the Godavari river basin. The area under forest cover constitutes 21.50 % of total geographical area of the district (Ground water Annual report 2016). The average normal rainfall in the district is 991.8 mm and actual rainfall is 916.3, most (83%) of it is received during the south-west monsoon. Out of 5.31 lakh ha of net area sown in the year 2012, only 45 % is under irrigation by different sources. The soils of erstwhile Karimnagar district are highly heterogeneous in nature. The major rock types occurring in the district are granites, gneisses, sandstone, limestone, shale, quartzite etc. The major soil types in this district are black soils (55%) and red sandy loam soils (45%). Methodology. For collection of soil samples 53 GCP location were pinned in respective study area by using GNSS viewer mobile application. Composite surface soil samples (0-15cm) were collected from fields of study area. The samples are air dried in shade and crushed with a wooden pestle and mortar, sieved through sieve (2 mm) and stored in properly labelled polythene bags for further analysis. The soil samples were analyzed in the laboratory for soil fertility parameters viz., soil texture, pH, EC (Jackson, 1973), available nitrogen (Subbiah and Asija 1956), phosphorus (Olsen et al., 1954), potassium, and DTPA extractable micronutrients (iron, manganese, copper and zinc) (Lindsay and Norvell 1978) by following the standard procedures. The results from laboratory analysis and location point files of Excel file are generated in ESRI shape file and imported in to QGIS software. Soil maps were generated using Inverse Distance Weighing (IDW) interpolation and employing kriging (Ravi et al., 2017) function for each soil quality parameter and the classes were assigned for the parameters based on standard USDA soil classification. Similar procedure was followed for the generation of all soil maps. RESULTS AND DISCUSSION The soil data analyzed for pH, EC, soil available N, P2O5, K2O, Fe, Mn, Cu and Zn were presented in detail in the below sections. Based on the results of the laboratory analysis, a total of 8 soil quality maps were generated using the QGIS software. Physico-Chemical Properties. Soil pH. The pH data of 53 sample locations are interpolated to generate maps are indicated that soils are slightly alkaline reaction (Fig. 2).The pH of the surface soils of different mandals of erstwhile Karimnagar district varied from 6.67 to 8.73 with overall mean value of 7.86 (Ravi et al, 2014). Low pH was noted in Korutla mandal (7.44) and high pH was recorded in Chandurthi mandal (8.24) soils (Table 2). The majority of soils in erstwhile Karimnagar district are neutral to strongly alkaline pH. Some soils in Mallapur, Raikal, Koratla and Konaraopeta mandals are neutral in reaction as depicted in Fig. 2. The observations on soil reaction of surface soils shown that 1.88% samples are acidic, 15.09% samples are neutral and 83.01% samples are alkaline in reaction (Table 1). Soil EC (1:2.5). The electrical conductivity of soils from study area of erstwhile Karimnagar district ranged from 0.11 to 1.05 dS m-1 (Table 2) with an overall mean value of 0.35 dS m-1. In general almost all soils of had low level of salinity and suitable for growing all crops. The observations on soil reaction of surface soils shown that 1.88% samples are acidic, 15.09% samples are neutral and 83.01% samples are alkaline in reaction (Table 1). Highest EC was recorded in Metpalli mandal (0.69) and least was in Konaraopet mandal (0.19) (Table 2). Soil available Macronutrients Soil Available Nitrogen. The available N in soils under study area of erstwhile Karimnagar district varies from 63 to 550 kg ha-1 with an overall mean value of 221 kg ha-1 (Table 2) which is lower than the critical limit suggested by USDA. The entire study area of erstwhile Karimnagar is low to medium in available nitrogen. Lowest nitrogen content recorded at Rudrangi mandal (119.70 kg ha-1) and highest was recorded at Korutla mandal (425.07 kg ha-1). Some soils from the Mallapur, Ibrahimpatnam, Koratla and Konaraopeta mandals are medium in available Nitrogen (Fig. 3). About 75.47% of samples out of 53 samples are fall under low available nitrogen (<280 kg ha-1) and 24.52% of samples are medium availability (280-560 kg ha-1) (Table 1). Similarly Ravi et al. (2017) reported 61.7% of 154 samples from rice growing area where under low N content. Madhavi et al. (2013) also reported that all mandals had low to medium nitrogen content in Nizamabad district. Soil Available Phosphorus. The available Phosphorus content of the soils from study area range varied from 5 to 322 kg ha-1 with an overall mean value of 123 kg ha-1. It depicted in Fig. 4 indicated that entire soils from study area are high in available phosphorus content except few soils from erstwhile Karimnagar (Fig. 4). The available P2O5 recorded least (43.63 kg ha-1) at Raikal mandal and was highest (205.85 kg ha-1) at Vemulawada mandal (Table 2). Similar results were reported by Ravi et al., 2017 in rice growing soils from erstwhile Karimnagar district. About 96.22 percent of erstwhile Karimnagar was delineated to have high available phosphorus and 3.7 percent of samples with low available phosphorus contents, respectively (Table 1). Soil Available Potassium. The available potassium content ranged between 135 to 630 kg ha-1 with an overall mean value of 304 kg ha-1 in soils collected from the study area of erstwhile Karimnagar district (Table 2.). The soils in this district are medium to high available K2O (Fig. 5). The results represented that 58.49 percent samples were contended with medium available soil potassium, while 41.50 percent of the regions were categorized as high available soil potassium, respectively. The highest available potassium was recorded at Ibrahimpatnam mandal (505.34 kg ha-1) and lowest was recorded at Metpalli mandal (155.52 kg ha-1) (Table 1). The similar results reported by Kamalakar et al. (2020) in sugarcane growing soils of Nizamabad district. Soil available micronutrients (Fe, Mn, Cu and Zn) Zinc. The data presented in Table 2 revealed that available Zn content in soils from study area of erstwhile Karimnagar district varied from 0.23 to 2.01 mg Kg-1 with overall mean value of 0.86 mg Kg-1 (Ravi et al, 2014). The availability of Zn in study area of this district was very low to adequate. The lowest value of available Zn recorded at Metpalli mandal (0.36 mg Kg-1) and highest was recorded in Chandurthi mandal (1.28 mg Kg-1). About 3.77%, 35.84% 49.05% and 11.32% of samples are found to be very low, low, marginal and adequate in available Zn content respectively (Table 1). Copper. The amount of copper ranged from 0.24 to 6.72 mg Kg-1 in the soil of study area of erstwhile Karimnagar district with an overall mean value of 1.20 mg Kg-1 (Reddy et al., 2014). The lowest value of available copper recorded at Chandurthi mandal (0.39 mg Kg-1) and highest recorded at Raikal mandal (3.53 mg Kg-1) (Table 2). An average 18.86% and 81.13% samples are marginal and adequate in available Cu content (Table 1). Fig. 7 depicts that most of study area is adequate in available copper. Iron. The DTPA extractable iron content in soil from the study area of erstwhile Karimnagar district are ranged from 2.03 to 43.23 mg Kg-1 with an overall mean value of 12.60 mg Kg-1 (Narsaiah et al., 2018). Lowest value of available iron recorded at Metpalli mandal (2.59 mg Kg-1) and highest was recorded at Konaraopet mandal (24.33 mg Kg-1) (Table 2). About 1.88%, 15.09%, 15.09% and 67.92% samples are fall under very low, low, marginal and adequate (Fig. 8) in available Fe content (Table 1). Manganese. The available Mn content in soils from study area of erstwhile Karimnagar district varied from 0.87 to 40.71 mg Kg-1 with overall mean value of 15.03 mg Kg-1 (Kamalakar et al., 2020). The availability of Mn in study area of this district was very low to adequate. The lowest value of available Mn recorded at Kodimial mandal (1.80 mg Kg-1) and highest was recorded in Mallapur (22.67 mg Kg-1) (Table 1). The 5.66% samples are very low, 20.75% samples are low, 32.07% samples are marginal (Fig. 9) and 41.50% samples are adequate in available Mn content in soils (Table 1). Correlation study from Table 3 reported that all the nutrients are positively correlated with soil reaction except Nitrogen , copper and Iron which are negatively correlated with soil reaction (r = -0.45, -0.03, -0.08) respectively (Table 3). Whereas Phosphorus, Potassium and Iron are negatively correlated with salinity (r = -0.31, -0.11, -0.24) respectively.