INTRODUCTION India covers up 328.8 million hectares, or 8% of the total land area in the globe. Of this land, about 51% is cultivated, compared to 11% globally. The present cropping intensity of country has been 142% registered. The current agricultural intensity in the nation is 142%. Furthermore, 65 percent of the total net sown area is contributed by agriculture on rainfed dryland. Due to nutrient shortages and toxicities, the country's 25 million ha of acidic soils have poor yield of less than 1 ton/ha. These arable fields might have their output doubled with the right amount of liming and fertilizer application. The soil of northern Madhya Pradesh is severely deficient in nitrogen and crops grown on it show deficiency symptoms in almost all the professions where it is not applied. Currently, 99 percent of soils suffer from nitrogen deficit, and crops cultivated on those soils invariably exhibit deficiencies in nearly all fields where it is not applied a sufficient supply of nitrogen is typically connected with vigorous vegetative development of plants and rich green colour of leaves (Katyal, 2016). Plants need high amount of phosphorus so it is a crucial element. Despite being abundant in soil in both organic and inorganic forms, it is the main nutrient that regulates plant growth. (Tandon, 1987), While potassium is the seventh most widespread element and the fourth most abundant mineral nutrient in the lithosphere (Sparks et al., 1985). On the crop's root system, Potassium is necessary for many metabolic processes carried out by living cells, including the breakdown of carbohydrates. When determining the long-term availability of potassium to crops and creating a solid foundation for fertilizer recommendations, understanding the various forms of potassium in soil and their distribution is of utmost importance (Lalitha and Dakshinamoorthy 2014). The district of Gwalior is located in Madhya Pradesh's northern region. Typically, the farmers in the region plant wheat, peas, black gramme, green gramme, pearl millet, mustard, peas, and sorghum in the Rabi season. Cereal, cereal-legumes, and cereal-oil seeds are the major cropping systems used by farmers. The present study was planned to determine the distribution of Nitrogen, Phosphorus and Potassium with relationship amongst different soil properties in different depth. Study area. The present study has conducted in research farms (sitholi, CRC 1, CRC 2, Turari 1, Turari 2, polyhouse 1, polyhouse 2) of ITM university Gwaior. The climate of Gwalior has subtropical with hot summers from late March to Early July. The humid monsoon season from late June to Early October, and cool dry winter from Early November to late February. Annual rainfall ranges from 700 to 800 mm, most of which fall during last June to the middle of September. In this area winter rains are occasional and uncertain. The city has a humid subtropical climate. Data Collection. The soil samples were collected from 0-15 cm, 15-30 cm and 30-45 cm depths of each pit with auger. Hence, samples were collected from soil of Sitholi, CRC1, CRC 2, TURARI 1 Turari 2 Polyhouse 1 and Polyhouse 2 at ITM research farm Gwalior. The soil samples were air dried in the shade, grinded with mortar and pestle and sieved through a 2 mm sieve. The samples were stored in polythene bags properly labeled for soil analysis. MATERIAL AND METHOD Measurements of selected physical and chemical properties of the soil sample as bulk density, texture, pH, EC, and Organic carbon were carried out by different methods. Moisture was determined by drying weighed quantity of the air-dried soil at 105° in electric oven for 24 hours (Piper, 1950). The pH of the soils was determined in soil water suspension using a glass electrode pH meter as described by Jackson (1967). The electrical conductivity of the soils was determined in soil water extract with the help of an electrical conductivity meter as given by Jackson (1967). The particle size analysis was done by the Bouyoucos hydrometer method as described by Piper (1950). Depth – wise soil samples were collected using a metal core sampler for bulk density analysis (Blake and Hartge 2018). The organic carbon percent of the soils was estimated by wet digestion method of Walkley and Black (1934). Available nitrogen content of individual soil samples was determined by alkaline permanganate method as given by Subbaiah and Asija (1956). Available phosphorus of the soil is determined by Olsen et al. (1954). While, the available potassium content of the soil is determined by Jackson, (1973) using Flame Photometer through Neutral ammonium acetate method. Statistical analysis. All statistical analysis was performed by OPSTAT software and WASP agri-software. The means of replicates and standard errors of the means were analyzed for selected soil properties under different locations and compared with two-way analysis of variance (ANOVA) test. RESULT AND DISCUSSION The experimental findings pertaining to present investigation entitled “Distribution and characterization of Nitrogen, Phosphorus and Potassium in different depth of soil profile in ITM research farm at Gwalior Madhya Pradesh” are discussed under: The soil profile are studied in different location of research farms (sitholi, CRC 1, CRC 2 Turari 1, Turari 2, Polyhouse 1, polyhouse 2). Mechanical analysis of soil profiles are presented in Table 1. Among the different soil fractions viz., sand, silt and clay, the later two fractions appeared to be the major one in all soil profiles. The textural classes was found to be sandy loam at all three depth. Percentage of sand, silt and clay varied from 56.4% -73.1%, 10%- 20.6% and 14.9% to 24.6% .respectively. The observed data showed that the silt particles decreased significantly with the increase in depth of soil at sitholi, CRC 2, turari 1, poly 1 and turari 2, whereas, it increased with increase in depth at poly 2 and CRC 1 location. While neutral in middile depth at turari 2. Studies given by Sharma et al. (2005); Dar (2009); Najar (2009); Naik (2014) reported that, sand decreased with soil depth while clay increased with soil depth in all the farms. Silt did not follow a regular pattern. These results are also found with the observations of Wani (2001); Wani et al. (2016). The increasing tendency of clay with depth in soil profiles may be due to leaching from upper to lower layer. Bulk density ranged from 1.55-1.48 in sitholi; 1.50-1.55 in CRC 1; 1.49-1.54 in CRC 2; 1.47-1.57 in Turari 1; 1.45 -1.51 in Turari 2; 1.52-1.59 in polyhouse 1; 1.55-1.60 in polyhouse 2. The observed data showed that the bulk density of soil increased significantly with the increase in depth of soil at all locations whereas, it decreased with increase in depth at sitholi location. Porosity ranged from 48.78-41.32 in sitholi; 49.56-43.29 in CRC 1; 49.36-42.87 in CRC 2; 45.40-40.26 in Turari 1; 43.62-37.71 in Turari 2; 49.20-41.98 in polyhose 1; 48.96-42.54 in polyhouse 2. It showed the increase in depth of soil the porosity decreased. The colour of the soil in the different locations at different depths varied from light yellow brown (10YR 5/3) /dark brown (10YR 4/3) to dark yellowish brown (10YR 3/4) (10YR 4/4) while as dark brown (10YR 4/3). The studied profiles could be attributed to presence of CaCO3 or may be due to coagulation of iron or calcium with humus (Dhir, 1967; Gupta, 1992). The various shades like dark brown, very dark brown, yellowish brown colour in surface and subsurface horizons of profiles indicate a good drainage condition of the soils (Mahajan et al., 2007) and may be ascribed to difference in soil organic matter, topographic position and geographical location (Sawhney et al., 2005; Khanday, 2013; Naidu and Sireesha 2013; Wani et al. 2017). Physico-chemical properties of the soil profiles are represented in Table 2. The pH values ranged from 8.08-7.81 in sitholi; 7.67-7.58 in CRC 1; 7.58-7.44 in CRC2; 8.27-7.90 in Turari 1; 8.18-7.98 in Turari 2; 8.16-7.60 in polyhouse 1; and 7.63-7.46 in polyhouse 2. The soils were slightly acidic to slightly alkaline in reaction. According to Thangaswamy et al. (2005) the higher pH could be due to increase in accumulation of exchangeable sodium, variation in organic matter and calcium carbonate. The decreased in pH with depth had also been reported by Wani et al. (2017). Similar results were given by Naik (2016). EC ranged from 0.28-0.55 dSm-1 in sitholi; 0.50-0.61 dSm-1 in CRC 1; 0.44-0.56 dSm-1 in CRC 2; 0.36-0.49 dSm-1 in Turari 1; 0.39-0.53 dSm-1 in Turari 2; 0.50-0.70 dSm-1 in polyhouse 1; 0.63-0.76 dSm-1 in polyhouse 2. EC values in the study area are not in safe limits (>0.1 dSm-1) with salinity and alkalinity hazards in the top soil. It showed increasing trend with the increase in the depth of soil. The EC in general showed increasing trend with depth as compared to surface horizons and was found to be in normal range in both horizons of poly 2 and CRC 1. All soil sample were found to be normal (EC< 1.0 dSm-1). The increase of electrical conductivity with depth could be attributed to leaching of bases from surface to sub surface horizons. The results are in agreement with the findings of Najar (2009); Tuba and Kaleem (2016). Organic carbon followed decreasing trend with in all seven locations Its ranged from 0.54-0.25 in sitholi; 0.49-0.30 in CRC 1; 0.50-0.30 in CRC 2; 0.48-0.29 in Turari 1; 0.50-0.31 in Turari 2; 0.56-0.29 in polyhouse 1; 0.45-0.30 in polyhouse 2. Low organic carbon % was observed at the surface layer of the locations. The high content of organic carbon in upper layers as against lower depths might be as a result of incorporation of crop residues and fallen leaves. These findings are in accordance with Sharma et al. (2005); Najar et al. (2009); Wani et al. (2016). Coarse-textured soils are generally low in organic carbon (Yadav and Meena 2009). The low organic carbon% in this type soils may be attributed to the high rate of organic matter decomposition under hyperthermic temperature regime which leads to high oxidation condition, removal of surface soils containing high organic carbon due to erosion which was responsible for the lower organic carbon (Rajeswar et al., 2009). Available N content varied from 124.74-112.24 kg ha-1 in sitholi; 139.94-125.99 kg ha-1 in CRC 1; 141.70-129.74 kg ha-1 in CRC 2; 142.30-131.02 kg ha-1 in Turari 1; 130.62-117.44 kg ha-1 in Turari 2; 147.60-134.90 kg ha-1 in polyhouse 1; 143.28-131.68 kg ha-1 in polyhouse 2. Low available N was observed in all the locations. The available nitrogen was higher in surface soils which showed a linear decreasing trend with an increase in soil depth in all the seven locations. Similar results were reported by Najar (2002); Dar et al. (2013) and Naidu, Sireesha (2013) and Wani et al. (2017). It is revealed from the results that efficiency of nitrogen is very low due to the fact that nitrogen lost through various mechanisms, like NH3 volatilization, de-nitification, chemical and microbial nitrogen fixation, leaching and run off (Sharma et al., 2008). Available P content varied from 13-11.68 kg ha-1 in sitholi; 12.14-9.64 kg ha-1 in CRC 1; 11.90-10.18 kg ha-1 in CRC 2; 10.96-9.98 kg ha-1 in Turari 1; 10.72-9.62 kg ha-1 in Turari 2; 12.68-1.02 kg ha-1 in polyhouse 1; 12.42-10.66 kg ha-1 in polyhouse 2; The available phosphorus showed a decreasing trend with all three depth, medium amounts were recorded in surface soils. In general the soils of upper layer showed higher levels of available phosphorus content followed by mid and low depths. Similar results about soils of Kashmir were also reported by Wani (2001); Dar et al. (2009). The lower phosphorus content in subsurface soils could also be attributed to the fixation of P by clay-minerals and oxides of iron and aluminium (Thangasamy et al., 2005; Khanday, 2013; Maqbool et al., 2017). Available K content varied from 304.94-240.04 in sitholi; 302.43-288.78 in CRC 1; 317.28-278.54 in CRC 2; 222.26-223.15 in Turari 1; 230.34-210.10 in Turari 2; 291.86-261.44 in polyhouse 1; 283.26-264.22 in polyhouse 2. Available K content decreased with increasing depth, low amount of K was found at surface layer in all seven location. At lower depth low to medium available K was observed. The available potassium showed a decreasing trend with depth, higher amounts were recorded in surface soils. These results are also noticed with those of Najar (2002) and Dar (2009). Correlation coefficients (r) of soil physico-chemical characteristics in 0-15 cm depth of soil. Perusal of the correlation coefficient (r = values) presented in Table 6, 7 and 8 revealed that electrical conductivity (r =0.582**) show highly positive significant correlation with nitrogen. While silt (r = 0.271) had positive non significant correlation. Phosphorus had highly significant positive correlation with potassium (r = -0.673**), porosity (r = 0.583**) and Bulk density (r = 0.679**). Porosity (r = 0.690**) and Bulk density (r = 0.478**), had highly significant positive correlation with potassium, While pH had highly negative significant negative relationship with available potassium. Sand had negative non-significant correlation with potassium.