Evaluation of soil fertility status in Inceptisol of Malkharauda block in Janjgir district of Chhattisgarh

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1 An Asian Journal of Soil Science Volume 8 Issue 1 June, 2013 Research Article Evaluation of soil fertility status in Inceptisol of Malkharauda block in Janjgir district of Chhattisgarh U.S.VERMA, G. K. JATAV AND R. K. BHAGAT MEMBERS OF RESEARCH FORUM : Corresponding author : G.K. JATAV, Department of Soil Science and Agricultural Chemistry, Institute of Agricultural Sciences, Banaras Hindu University, VARANASI (U.P.) INDIA gouravjatav143@gmail.com Co-authors : V.S. VERMA AND R.K. BHAGAT, Department of Soil Science and Agricultural Chemistry, Indira Gandhi Krishi Vishwavidyalaya, RAIPUR (C.G.) INDIA uvverma@yahoo.com bhagatrakesh.agb@gmail.com Received : ; Revised : ; Accepted : Summary A Study was undertaken to evaluate the fertility status in Inceptisols of Malkharauda block, Janjgir- Champa district, Chhattisgarh during which covers 110 villages. The geo referenced surface (0-0.15m) soils samples were systematically collected from village by using global positioning system where 1803 sample identified as Inceptisols which were taken for analysis of macronutrient i.e. available nitrogen, phosphorus, potassium and micronutrient i.e.dtpa-extractable zinc, copper, iron, manganese content for delineations of the fertility status in relation to salient physico-chemical characteristics and categorized as low, medium and high as per criteria followed in the soil testing laboratory. Its characterized moderate to neutral in soil reaction, soluble salt content comes under safe limit for all crops. The organic carbon level exhibited low to medium. The Inceptisol of the area showed low in available N and P, and medium level in available K where micronutrient showed sufficient except Zn. Based upon the co-efficient of correlation between macronutrients and soil properties ph showed positive correlation with macronutrient and negative correlation with micronutrient where organic carbon showed positive correlation with available nitrogen and potassium. Key words : Fertility status, Micronutrients, Majornutrient, Inceptisol How to cite this article : Verma, U.S., Jatav, G.K. and Bhagat, R.K. (2013). Evaluation of soil fertility status in Inceptisol of Malkharauda block in Janjgir district of Chhattisgarh. Asian J. Soil Sci., 8(1):. Introduction The populations of India continue to increase, human disturbance of the earth s ecosystem to produce food and fibre will place a greater demand on soils to supply essential nutrients. The practice of intensive cropping with hybrid varieties for boosting food production in India caused nutrient depletion in soils of India. Soil fertility has a direct relation with the crop yields, provided other factors are in optimum level. Soil fertility must be periodically estimated as there is continues removal of macro and micro nutrients by the crop intensively grown in every crop season. In order to achieve higher productivity and profitability, every farmer should realize that fertility levels must be measured as these measurements can then be used to manage soil fertility. It is determined by the presence or absence of nutrients i.e. macro and micronutrients. Balanced nutrient use ensures high production level and helps to maintain the soil health. Fertilizing soils to bring all the deficient elements at high levels as to provide sufficient ionic activity in soil solution for crop uptake is one of the most important considerations for maximization of the crop yield. Macronutrients (N, P and K) and micronutrients (Zn, Fe, Cu and Mn) are important soil elements that control its fertility. Soil fertility is one of the important factor controlling yields of the crops. Soil characterization in relation to evaluation of fertility status of the soils of an area is an important aspect in context of sustainable agriculture production. Soil testing is the key to fertility management while reclamation and rehabilitation of degraded lands is strategic to maintain over all soil health. Soil test-based fertility management is an effective tool for increasing productivity of agricultural soils that have high HIND AGRICULTURAL RESEARCH AND TRAINING INSTITUTE

2 U.S.VERMA, G. K. JATAV AND R. K. BHAGAT degree of spatial variability resulting from the combined effects of physical, chemical or biological processes (Goovaerts, 1998). However, major constraints impede wide scale adoption of soil testing in most developing countries. In India, these include the prevalence of small holding systems of farming as well as lack of infrastructural facilities for extensive soil testing (Sen et al., 2008). The variability in fertility caused by application of fertilizers in individual farms is one factor that is difficult to account. However, it is possible to measure the natural variation in soil fertility by considering the factors which influence it. Slope, topography and soil types can account for most of the natural variation in fertility. It will be of great significance if soil test crop response based recommendation can be provided even on this basis. More site specific recommendations can still be provided on the basis of field soil testing to farmers who are applying very high doses of fertilizer and who show interest on testing their soils. The soil testing results indicate nothing about the potential of soil to produce or amount of nutrients to be added to achieve a desired yield (Melsted and Peck, 1973). The interpretation of test results is carried out by correlating data obtained by analysis of soil samples with known field crop response. Chhattisgarh state is carved out of the erstwhile Madhya Pradesh. It lies between 17 o o 8 N latitude and 80 o o 24 E longitude. The state measures 640 km from North to South and 336 km from East to West with a total geographical area of 1,35,194 km -2. The state shares its boundaries with the 6 Indian states i.e. Madhya Pradesh on the northwest, Uttar Pradesh on the north, Jharkhand on the north-east, Orissa on the south-east, Andhra Pradesh on the south and Maharashtra on the south-west. Chhattisgarh state has four major soils type i.e. Entisols, Inceptisols, Alfisols, Vertisols in whole area and very small area of Mollisols under forest region of Bastar plateau. Almost all soils are deficient in nitrogen, phosphorus and medium to high in potassium. Zinc deficiency is commonly observed in this region. Study area : Malkharouda is located at Janjgir-champa district lying between 21 52' 60 N latitude to 82 27' 00 E longitudes. It has an average elevation of 288 m. Systematic survey was carried out for evaluation the soil fertility status of Malkharouda block of Janjgir-champa district, a surface (0-15 cm, depth) soil samples were collected from 110 villages sites by following the standard procedures of soil sample collection. Soil samples were collected with the help of soil auger and local spade with proper labels. The Inceptisol group of the soil covered under the different villages of the Malkharouda block in Janjgir district of Chhattisgarh has been taken for fertility evaluation on various aspects. Resource and Research Methods Soil samples collected from the study area were dried and crushed with the help of wooden rod and passed through 2 mm sieve and then used for the determination of soil ph, organic matter, macronutrients and micronutrients content by adopting standard laboratory method. Soil ph was determined by glass electrode ph (Piper, 1950), electrical conductivity with Solu-bridge method (Black, 1965), organic C by wet digestion method (Walkley and Black s rapid titration method, 1934), available nitrogen was estimated by alkaline KMnO 4 method (Subbiah and Asija, 1956), available phosphorus was extracted by 0.5M NaHCO 3 solution buffer at ph 8.5 (Olsen et al.,1954) and phosphorus in the extract was determined by ascorbic acid method (Watanabe and Olsen, 1965), available potassium was extracted by shaking with neutral normal ammonium acetate for 5 minutes (Hanway and Heidal, 1952) and then K in the extract was estimated by flame pho tometer. T he micronutrients Zn, Cu, Fe and Mn were extracted by using 0.005M diethylene triamine penta acetic acid (DTPA), 0.01M calcium chloride dehydrate and 0.1M triethanol amine buffered at ph 7.3 (Lindsay and Norvell, 1978) and concentrations were analyzed by atomic absorption spectrophotometer The data on available Fe, Cu, Mn and Zn of soils were characterized for deficient and adequate status using the threshold values 4.5 mg kg -1 for Fe, 0.2 mg kg -1 for Cu, (Katyal and Randhawa, 1983), 3 mg kg -1 for Mn (Shukla and Gupta,1975) and 0.6 mg kg -1 for Zn (Katyal,1985).The samples were categorized as per the rating limit given in Table 2. Research Findings and Discussion The experimental findings obtained from the present study have been discussed in following heads: Soil reaction (ph) : A study on soil ph presented in Table 1 revealed that the soils of farmer s field was acidic to alkaline in reaction and ph ranged from 4.7 to 7.1 with an average value 6.0 in Inceptisols of Malkharauda block. Considering the Table 2, the soils having ph <5.0 are considered strongly acidic, ph 5.0 to 6.0 as moderately acidic, ph 6.1 to 6.5 as slightly acidic, neutral considered for ph 6.6 to 7.5 and slightly alkaline soils are considered for ph 7.6 to 8.5. In general, out of 1803 samples, nearly % samples were observed under moderately acidic (5-6.0), 36.11% under slightly acidic ( ), 0.44% under strongly acidic (<5.0) and 11.09% samples were categorized under neutral soil in Inceptisols. Electrical conductivity (EC) : The electrical conductivity (EC) varied from 0.05 to 0.74 HIND AGRICULTURAL RESEARCH AND TRAINING INSTITUTE 104 Asian J. Soil Sci., (June, 2013) 8 (1) :

3 SOIL FERTILITY STATUS OF MAJOR NUTRIENT IN Inceptisol OF MALKHARAUDA BLOCK IN JANJGIR DISTRICT ds m -1 with a mean value of 0.20 ds m -1 at 25 o C (Table 1) of the Malkharauda block. The total salt content of these soils expressed as EC are categorized as <0.1, 0.1 to 0.2, 0.2 to 0.3 and >0.3 ds m -1. The normal EC may be ascribed to leaching of salts to lower horizons due to its light textured nature and heavy rainfall and surface run-off. Data presented in Table 3 revealed that in Malkharauda block, majority of soil samples (75.60%) were found under ds m -1 EC limit. All the soil samples have safe range of electrical conductivity with respect to crop growth and development. Organic carbon (OC) : Data presented in Table 1 and 3 revealed that most of the soils were having low to medium status of organic carbon. It ranged from 0.11 to 0.78 per cent with a mean value of 0.49 per cent in Inceptisols of Malkharauda block. Nearly 99.0 per cent soil samples of Malkharauda block of Janjgir-Champa district were low to medium in organic carbon content considering the soils having <0.25% as very low, per cent as low, per cent medium and >0.75 per cent as high in OC status. The majority of the soil samples analyzed for soil organic C content i.e per cent samples were rated as medium, per cent samples were rated as low and only 1.44 per cent samples were reported as very low classes in Inceptisols. High temperature and good aeration in the soil increased the rate of oxidation of organic matter in reduction of organic carbon content. The high temperature prevailing in the area is responsible for the rapid burning of organic matter, thus resulting in medium organic carbon content of these soils. Similar results were also noted by Sharma et al. (2008) in Table 1: Salient soil properties of study area Soil characteristics Range Mean ph (1:2.5,Soil:water) E.C. (dsm -1 ) O.C. (%) Available N (kg ha -1 ) Available P (kg ha -1 ) Available K (kg ha -1 ) Available Fe (mg kg -1 ) Available Mn (mg kg -1 ) Available Cu (mg kg -1 ) Available Zn (mg kg -1 ) Table 2: Limits for the soil test values used for rating the soil Classification for ph values Strongly acid Moderately acid Slightly acid Neutral Slightly alkaline < Classification for total soluble salt content (EC as ds m -1 ) < >0.3 Parameters Very low Low Medium High O.C. (%) < >0.75 Macronutrients Parameters Low Medium High Av. N (kg ha -1 ) < >560 Av. P (kg ha -1 ) < >25 Av. K (kg ha -1 ) < >335 Micronutrients Deficient Sufficient High level Av. Fe (mg kg -1 ) <4.50 >4.50 >9.00 Av. Mn (mg kg -1 ) <3.50 >3.50 >7.00 Av. Cu (mg kg -1 ) <0.20 >0.20 >0.40 Av. Zn (mg kg -1 ) <0.60 >0.60 >1.20 HIND AGRICULTURAL RESEARCH AND TRAINING INSTITUTE 105 Asian J. Soil Sci., (June, 2013) 8 (1) :

4 U.S.VERMA, G. K. JATAV AND R. K. BHAGAT soils of Amritsar district. Available macronutrients status of soils : Available N status : The available N content (Table 1) of Inceptisols varied from 88 to 326 kg ha -1 with an average value of 179 kg ha -1. Considering the soil test rating for available N (<280 as low, as medium and >560 as high in the status of N), the soil sample i.e per cent, were found as low available N content in Inceptisols. In this way, almost all the soil samples tested for available N were found to be deficient in N. Although, it is fact that the available N analyzed by alkaline KMnO 4 method as suggested by Subbiah and Asija, (1956) do not exhibit the exact availability of N in dry soil. It is the measure of the oxidisable N in dry soil. Available P status : The average available P content in various soils was noted from 0.2 to 26.4 kg ha -1 with a mean value of 7.4 kg ha -1 (Table 1) in the study area. The range is quite large which might be due to variation in soil properties viz., ph, organic matter content, texture and various soil management and agronomic practices. Considering the soil test rating for available phosphorus (<12.5 kg ha -1 as low, kg ha -1 as -1 medium and >25 kg haas high) majority of the soils fell under low status. Nearly, per cent, soil samples were observed under low status in available phosphorus.the per cent samples of study area were categorized under medium available P content in Inceptisols. Phosphorus is present in soil as solid phase with varying degree of solubility. When water soluble P is added to the soil, it is converted very quickly to insoluble solid phase by reacting with soil constituents. These may include calcium Cate (Olsen, 1953), Fe and Al oxides (Dean and Rubin, 1947 and Chu et al. 1962) and partly organic matter. These reactions affect the availability of P and as a result of these reactions, a very small amount of total P is present in soil solution at any time reflected by soil testing. However, a low to medium range of soil available P under study area may be mostly affected by past fertilization, ph, organic matter content, texture various soil management and agronomic practices (Verma et al., 2005). Available K status : The results showed that available potassium content varied from 104 to 479 kg ha -1 with an average value of 278 kg ha -1 in Inceptisols of Malkharauda block (Table 1). Considering the soils having <135 kg ha -1 as low, kg ha -1 as medium and >335 kg ha -1 as high in available potassium contents, the data presented in Table 4 revealed that in Inceptisols about per cent samples had high, per cent medium and 3.55 per cent in low available K content. These results confirmed the finding as reported by Jatav and Mishra (2012) in the soils of Inceptisols group of Baloda block of Janjgir-Champa district of Chhattisgarh. Adequate (medium or high) available K in these soils may be attributed to the prevalence of potassium-rich minerals like Illite and Feldspars (Sharmaet al., 2008). Available micronutrients status of soils : Available Fe status : The DTPA-extractable Fe content of soils under study Table 3: Percentage of soil sample fallen under different rating of soil test values Classification for ph values Strongly acid Moderately acid Slightly acid Neutral Slightly alkaline Classification for total soluble salt content (EC as ds m -1 ) Parameters Very Low Low Medium High O.C. (%) Macronutrients Parameters Low Medium High Av. N (kg ha -1 ) Av. P (kg ha -1 ) Av. K (kg ha -1 ) Micronutrients Deficient Sufficient High level Av. Fe (mg kg -1 ) Av. Mn (mg kg -1 ) Av. Cu (mg kg -1 ) Av. Zn (mg kg -1 ) HIND AGRICULTURAL RESEARCH AND TRAINING INSTITUTE 106 Asian J. Soil Sci., (June, 2013) 8 (1) :

5 SOIL FERTILITY STATUS OF MAJOR NUTRIENT IN Inceptisol OF MALKHARAUDA BLOCK IN JANJGIR DISTRICT samples varied from 3.2 to 60.1 mg kg -1 with an average of 21.0 mg kg -1 (Table 1). Considering 4.5 mg kg -1 DTPA-extractable Fe as critical limit (Table 2) (Lindsay and Norvell, 1978), 1.44 per cent soil samples were found deficient, per cent sufficient and per cent samples recorded higher level of available Fe (Table 3). High available Fe content in soils of Malkharauda block might be due to its topography and cultivation of rice, which induced prolonged submergence coupled with reducing conditions. Majority of the soils were not deficient in Fe as the amount of iron required by crops is being released by iron bearing minerals in these soils. The soil ph had reverse effect on the availability of Fe content in soil. Available Cu status : The DTPA-extractable Cu content of soils varied from 0.2 to 11.1 mg kg -1 with an average content of available Cu recorded as 4.1 mg kg -1 (Table 1). Considering deficient (<0.2), sufficient ( ) and high ( >0.4 mg kg -1 ) level DTPAextractable Cu as critical limit (Follett and Lindsay, 1970) in Table 2, per cent soil samples were found to be in higher level, and only 0.78% in sufficient available content of Cu, in soilsof Malkharauda block (Table 3). Most of the soil samples were found under high level in available Cu content with a model class of >0.4 mg kg -1 DTPA-extractable Cu (Table 3). Available Mn status : The available Mn content ranged from 3.9 to 66.0 mg kg - 1 with mean value of 26.0 mg kg -1 in soils of study area (Table 1). Considering the soil test rating for DTPA-extractable Mn (<3.5 mg kg -1 as deficient, 3.5 to 7.0 mg kg -1 as sufficient and >7.0 mg kg -1 as higher level), the data presented in table 3 revealed that nearly per cent samples were having higher level (>7.0 mg kg -1 ) and 3.38 per cent in sufficient level ( mg kg -1 ) in available Mn under Inceptisols.The Mn bearing minerals in the parent material might be the reason for higher Mn content in the soils and due to better supply of manganese to rice in flooded soil because Mn is soluble under relatively acid and reducing conditions. Mn is mobilized under reduced conditions during rice cultivation which resulted in higher availability of Mn to rice (Mandal and Haldar, 1980). Available Zn status : The DTPA-extractable Zn varied from 0.1 to 5.8 mg kg -1 with an average available zinc of 1.1 mg kg -1 in the study area (Table 1). Considering the soil test rating for DTPA-extractable Zn (<0.6 as deficient, as sufficient and >1.2 mg kg -1 as high level) as critical limit for Zn deficiency (Lindsay and Norvell, 1978) (Table 2), per cent samples were deficient, per cent sufficient and per cent samples were found in higher level of available Zn content (Table 3). In well drained aerated calcareous soils, zinc exists in oxidized state and their availability becomes low. The results are in conformity with the findings of Rajeswar et al. (2009) in Garikapadu of Krishna district of Andhra Pradesh. Relationship between soil characteristics and available N, P and K in Inceptisols : A significant positive correlation was recorded between available Pand ph (r = 0.134**). Similar results were also reported by Singh and Singh (1985) in Beel soils of Assam. Positive non-significant correlation (r = 0.033) was found between available P and organic carbon (Table 4). This relationship was also observed by Kumar et al. (2009). Available N showed a positive non-significant correlation with Table 4: Correlation co-efficient (r) between physico-chemical properties and available N, P and K in Inceptisols of Malkharauda block ph EC OC N P K ph EC 0.215** OC 0.183** 0.101** N 0.192** 0.102** 0.077* P 0.134** 0.067* ** K 0.067* 0.068* 0.077* * * and ** Indicates significance of values at P=0.05 and 0.01, respectively Table 5: Correlation co-efficients (r) between physico-chemical properties and DTPA-extractable Zn, Cu, Fe and Mn in Inceptisols of Malkharauda block Available Micro-nutrients Soil properties Cu Mn Fe Zn ph ** ** ** ** EC * ** ** O.C ** ** ** * and ** Indicates significance of values at P=0.05 and 0.01, respectively HIND AGRICULTURAL RESEARCH AND TRAINING INSTITUTE 107 Asian J. Soil Sci., (June, 2013) 8 (1) :

6 U.S.VERMA, G. K. JATAV AND R. K. BHAGAT available K (r=0.058) in Table 4. The positive relation among the major nutrients is the result of synergistic effects. Available N showed significant positive correlation with ph (r = 0.192**) and OC (r = 0.183**) as presented in Table 4. The results indicated that available N increased with rise in ph. Kumar et al. (1995) also reported the identical results. Similarly, OC level also markedly affects the soil N status and the results are in agreement with those of workers like Meena et al. (2006) and Kumar et al. (2009). The available K was found to be positively and significantly correlated with organic carbon (r=0.077*) in Table 4. Higher K with more organic carbon might be due to creation of favourable soil environment with presence of high organic carbon matter and release of K from organic complexes in soil solution. Similar results were also reported by Meena et al. (2006), Sharma et al. (2008) and Waghmare et al. (2009). Relationship between soil characteristics and DTPAextractable Zn, Cu, Fe and Mn in Inceptisols : A (Table 5) significant negative correlation was observed between available Fe with ph (r = **) which confirm the observations reported by Kumar et al. (2009) in Santhal Paraganas region of Jharkhand, The possible reason might be due to the formation of insoluble higher valent oxides of Fe at high ph. The negative and significant correlations (r = **, r = ** and r = **) of ph was reported with available zinc, available Cu and available Mn, respectively. These results are in conformity with the findings of Yadav and Meena (2009). The correlation (r = ) of Fe with EC showed a negative and non significant result (Table 5). The organic C content also showed negative and significant correlations with available Mn, Fe and Zn (Table 5). Similar observations were also observed by Sharma et al. (2006) and Rai et al. (1970) who claimed a negative correlation between available Mn and organic C level in soils of Madhya Pradesh. Conclusion : It can be concluded that most of the Inceptisols of Malkharauda block in Janjgir-Champa district of Chhattisgarh showed low status in available N and P, medium to high level in available K and characterized under moderately acidic to neutral in soil reaction (ph) and less than 1.0 ds m -1 soluble salt content (EC) which comes under safe limit for all soils. Most of soil samples observed high level of DTPA-extractable Fe, Mn and Cu, whereas, Zn deficiency was observed in study area. The organic carbon level exhibited low to medium and positively significant correlation was exhibited amongst OC and available N. Hence, the soils require attention regarding nutrient management practices and regular monitoring of soil health for better crop production, in future. Literature Cited Black, C.A. (1965). Method of soil analysis. American Agronomy Inc., Madison, Wisconsin, USA. pp Chu, C. R., Moschler, W. W. and Thomas, G. W. (1962). Rock phosphate transformation in acid soils. Soil Sci. Soc. Amer. Proc., 26: Dean, L.A. and Rubin, E.J. (1947). Anion exchange in soils. Exchangeable phosphorous and anion exchange capacity. Soil Sci., 63: Goovaerts, P. (1998). Geo-statistical tools for characterizing the spatial variability of microbiological and physic-chemical soil properties. Biol. Fertil. Soil., 27: Hanway, J.J. and Heidel, H. (1952). Soil analysis methods as used in Iowa State. College soil testing laboratory. Bulletin, 57: Jatav, G.K. and Mishra, V.N. (2012). Evaluation of soil fertility status of available N,P and K in Inceptisol of Baloda Block in Janjgir District of Chhattisgarh. Asian J. Soil Sci., 7(1): Katyal, J.C. and Randhawa, N.S. (1983). In Micronutrient F. A. O. fertilizer and plant nutrition bulletion No.5, Rome, 92 p. Katyal, J.C. (1985). Research achievements of the all India coordinate scheme on micronutrients in soils and plants. Ferti. News, 30(4): Kumar, P., Sharma, S.P. and Sharma, P.D. (1995). Distribution at N, P and K in soan river valley soils of lower shiwaliks. J. Indian Soc. Soil Sci., 43 (3): Kumar, R., Sarkar, A.S., Singh, K.P., Agarwal, B.K. and Karmakar, S. (2009). Appraisal of available nutrients status in Santhal Paraganas region of Jharkhand. J. Indian Soc. Soil Sci., 57(3): Lindsay, W.L. and Norvell, W.A. (1978). Development of DTPA soil test for zinc, iron, manganese and copper. Soil Sci. Soc. Amer. J., 42: Mandal, L.N. and Haldar, M. (1980). Influence of phosphorus and zinc application on the availability of zinc, copper, iron, manganese and phosphorus in warelogged rice soils. Soil Sci.,130: Meena, H.B., Sharma, R.P. and Rawat, U.S. (2006). Status of macro and micronutrients in some soils of Tonk District of Rajasthan. J. Indian Soc. Soil Sci., 54(4): Melsted, S.W. and Peck, T.R. (1977). The Mitscherlich- Bray growth functions soil testing: Correlation and interpretation analytical results. Amer. Soc. Agron., 29: Olsen, S.R., Cole, C.V., Watanabe, F.S. and Dean, L.A.(1954). Estimation of available phosphorus in soil by extraction with sodium bicarbonate. USDA, Circ., 939. Olsen, S.R. (1953). Inorganic phosphorous in alkaline and calcareous soils In W.H Pierre and A.G Norman (ed. Soil and fertilizer Phosphorus), Ame. Soc. Agron. Madison Wis., Agronomy, 4: Piper, C.S. (1950). Soil and plant analysis. Inter-Science Publication., NEW YORK. U.S.A. HIND AGRICULTURAL RESEARCH AND TRAINING INSTITUTE 108 Asian J. Soil Sci., (June, 2013) 8 (1) :

7 SOIL FERTILITY STATUS OF MAJOR NUTRIENT IN Inceptisol OF MALKHARAUDA BLOCK IN JANJGIR DISTRICT Rajeswar, M., Rao, C.S., Balaguravaiah, D. and Khan, M.A.A. (2009). Distribution of available macro and micronutrients in soils Garikapadu of Krishna District of Andhra Pradesh. J. Indian Soc. Soil Sci., 57(2): Sen, P., Majumdar, K. and Sulewski, G. (2008). Importance of spatial nutrient variability mapping to facilitate SSNM in small land holding systems. Indian J. Fert., 4(11): Sharma, P.K., Sood, A., Setia, R.K., Tur, N.S., Mehra, D. and Singh, H. (2008). Mapping of macronutrients in soils of Amritsar district (Punjab) A GIS approach. J. Indian Soc.Soil Sci., 56(1): Shukla, U.C. and Gupta, B.L. (1975). J. Indian Soc. Soil Sci., 23: Singh, R.K. and Singh, H.P. (1985). Nutrient status of Beel soils in Assam. J. Indian Soc. Soil Sci., 33(1): Subbiah, B.V. and Asija, G.L. (1956). A rapid procedure for the determination of available nitrogen in soils. Curr. Sci., 25: Verma, V.K., Setia, R.K., Sharma, P.K., Singh, C. and Kumar, A. (2005). Pedospheric variations in distribution of DTPA-extractable micronutrients in soils developed on different physiographic units in central parts of Punjab, India. Internat. J. Agric. & Biol.,7: Waghmare, M.S., Bavalgare, V. G., Deshmukh, V.A. and Takankhar, V.G. (2009). Status of available N,P and K in some soil of Ausa tahsil of Latur district. Internat. J. Trop. Agric., 27(1-2): Walkey, A. and Black, C. A. (1934). An examination of the degtjareff method for detemining the soil organic matter and a proposed modification of the chromic acid titration method. Soil Sci., 37: Watanable, F.S. and Olsan, S.R. (1965). Test of an ascorbic acid method for determining phosphorous in water and NaHCO 3 extracts from soil. Soil Sci. Am. Proc., 29: Yadav, R.L. and Meena, M.C. (2009). Available micronutrients status and their relationship with soil properties of Degana soil series of Rajasthan. J. Indian Soc. Soil Sci., 57(1): ******** ****** **** HIND AGRICULTURAL RESEARCH AND TRAINING INSTITUTE 109 Asian J. Soil Sci., (June, 2013) 8 (1) :