Soils In Study Area Research Articles

Rainwater Runoff Estimation using Empirical formulae Computed in C Programming Software for Puriliya District of West Bengal

Purulia is a drought prone district of India. Monsoonal vagaries along with ustic soils and poor groundwater availability augment the sufferings of the district's residents from acute water scarcity. The main objectives of study are to identify the needs of rainwater harvesting and the possibilities of group based water distribution policy for the Bandu River basin area. Last ten years rain fall details has been collected from the meteorological department of West Bengal4 and based on the study area soil curve number, runoff coefficient, the runoff has been estimated for the basin through empirical formulae given by SCS Relation Curve number and Aiexander Binnie5,6 method computed by help of C programming software. Facts have been represented through suitable cartographic and statistical techniques, i.e., comparison of rainfall and runoff data. The study concludes rain water harvesting be the viable answer to the threat possessed by drought situation in Puruliya. And using software leads to increase in accuracy and speed of determination of runoff.

Land Evaluation for Alternate Land Use Planning of Sugarcane Growing Soils of Chittoor District in Andhra Pradesh

Seventeen typical pedons representing major sugarcane growing soils of Chittoor district were studied and evaluated by using qualitative and quantitative methods. The qualitative method employed were USDA land capability classification and land suitability classification, while the quantitative evaluation method includes Riquier’s parametric approach. The land evaluation methods indicated that information on production potential of soils provide a basis for comparison among different soils. The soils of study area were classified into land capability classes IV, V and VI. However, the land suitability evaluation suggested that these sugarcane growing soils were moderately suitable (S2) (P2, P5, P6, P13 and P16) and moderate to marginally suitable (S2-S3) (P1, P3, P4, P7, P8, P9, P10, P11, P12, P14, P15 and P17) for growing sugarcane crop. Riquier’s parametric approach was found to be good indicator for identification of production potential of sugarcane growing soils. The land evaluation study revealed that, characteristics and suitability of these soils for sugarcane crop were highly variable, hence their management must be site specific. Soil management strategies based on crop residue retention, nutrient recycling, minimum tillage, crop rotation, cover crops and inter cropping not only helps to conserve soil and water more effectively in sugarcane growing soils but also increase organic matter content and improve fertilizer use efficiency. Adoption of suggested ameliorative measures and land use not only improves the yields but also sustains the soil productivity.

Comparison of Interpretation Between CPT and Res-2d Methods for Geostratigraphic Profiling Determination of Kota Depok

In its simplest application, the cone penetrometer offers a quick, expedient, and economical way to profiling a subsurface soil layering at a particular site. No drilling, soil samples, or spoils are generated, therefore, cone penetration test CPT is less disruptive from an environmental standpoint. The continuous nature of CPT reading permits clear delineations of various soil strata, their depths, thicknesses, and extent, perhaps better than conventional rotary drilling operations that use a standard drive sampler at 5-ft vertical intervals. The cone penetrometer is instrumented with load cells to measure point stress and friction during a constant rate of advancement. The results can be interpreted within different theoretical frameworks or by using empirical methods, or both. RES-2D (resistivity – two dimension) completed by Geoscanner devices is applicable to interpret the soil profiling from soil exploration works. Generally, the geoscanner is used to assess the geological subsurface condition for mining works. This paper is addressed to compare the results for soil classification in Kota Depok, West Java using a cone penetration test and RES-2D. From both methods, the result of soil strata shows the soft soil in study area can be classified as clay layers from ground surface to the depth of 15.0 m. However, the CPT is less applicable to measure exactly the elevation of ground water table than RES-2D. In addition, RES-2D is also less applicable to predict the soil properties of the soil type than CPT. In general application, both devices can be applied to soil investigation for geotechnical works.

Ecological risk assessment of heavy metals pollution on irrigated soil along Salanta River Valley, Kano State Nigeria

This paper assessed the heavy metals pollution in irrigated soil of salanta river valley of Sharada industrial area with aim of assessing the potential ecological risk of Cd, Cu, Cr and Zn. Soil samples were collected from five plots randomly selected along the stream and heavy metals (Cd, Cu, Cr and Zn) and pH were analyzed using Atomic Absorption Spectrophotometer and pH meter respectively. The mean values and standard deviation of heavy metals in the study area shows that there is variation in the mean values among the heavy metal in the study area in which Cr recorded mean values of 2.30mg/kg ± 0.45, Cu 1.01 mg/kg ±0.78, Cd 3.02 mg/kg ± 0.66, Zn 26.4 mg/kg± 5.45 and mean pH 6.8 ± 0.51. The Cd, Cu and Zn were found below European regulatory values, the mean value of Cd (3.02mg/kg) is found above EU regulatory values (3.0mg/kg) and the pH value of the study area shows that the soil is slightly acidic and can influence the availability and solubility of the heavy metals in the area. The assessment also show that Cd (Pij,= 1.0), Cu (Pij,= 0.007) and Zn (Pij,= 0.088) are heavily polluted the soil of the area, and also slightly polluted with Cr (Pij,= 0.025). However, the potential ecological risk assessment show that Cr (Eri = 0.005) and Cu (Eri = 0.003) have low potential ecological risk in the area; Zn (Eri = 0.04) has moderate potential ecological risk while Cd (Eri = 0.088) is considerable potential ecological risk in the soil of study area. It was recommended that the industries should treat their waste water before discharge and farmers should avoid using waste water directly, sewage sludge and effluent for watering and manure respectively.Key words: Heavy metals, pollution, soil, ecological risk

Lead Contamination In Soil Of Yogyakarta City, Indonesia

This paper investigates on Pb concentrations and mobility in soil of overall Yogyakarta City, Indonesia. The objectives of this study include to investigate Pb concentrations in the surface soil throughout Yogyakarta and to study their possible sources and potential environmental impacts. The soil samples from 168 locations in Yogyakarta was obtained, representing different land use and traffic conditions. Spatial analysis and sequential extraction analysis were performed. Generally, contour pattern of Pb value clearly shows that high value is concentrated in the middle and few north part of the study area, confirmed by traffic condition in the study area. In general, the results of sequential extraction analysis shows that Pb was predominantly associated with exchangeable fraction. The presence of lead in the exchangeable fractions may pose a serious environmental concern since they are highly soluble and potentially bio-available in the soil of study area. Keywords: Soil, lead contamination, GIS, sequential extraction.

Analysis of natural radionuclides in soil samples of Purola area of Garhwal Himalaya, India.

Naturally occurring radioactive materials are widely spread in the earth's environment, being distributed in soil, rocks, water, air, plants and even within the human body. All of these sources have contributed to an increase in the levels of environmental radioactivity and population radiation doses. This paper presents the activity level due to the presence of (226)Ra, (232)Th and (40)K in soil samples of Purola area in Garhwal Himalaya region. The measured activity of (226)Ra, (232)Th and (40)K in collected soil samples of Purola was found to vary from 13±10 to 55±10 Bq kg(-1) with an average of 31±2 Bq kg(-1), 13±10 to 101±13 Bq kg(-1) with an average 30±3 Bq kg(-1) and 150±81 to 1310±154 Bq kg(-1) with an average 583±30 Bq kg(-1), respectively. The radium equivalent activity in collected soil samples was found to vary from 47 to 221 Bq kg(-1) with an average of 115 Bq kg(-1). The total absorbed gamma dose rate in this area was found to vary from 22 to 93 nGy h(-1) with an average of 55 nGy h(-1). The distribution of these radionuclides in the soil of study area is discussed in details.

Influence of different stands of sal (Shorea robusta C. F. Gaertn.) forest of Bangladesh on soil health

The study was conducted in Dukhula sadar and Gasabari forest range under Madhupur Sal Forest of Bangladesh to determine the soil nutrient composition and isolation of fungi with varying stands. Three stands viz. pure sal, plantation and mixed were considered as treatment of the study. A quadrate sample plot of 10×10 m2 size was measured to collect soil samples for both chemical analysis and fungi isolation. Soil pH, electrical conductivity, organic matter content, total N, available P, exchangeable K, available S, fungal abundance and colony character (cm) were determined to achieve the objective of the study. The results revealed that soil pH and electrical conductivity were highest (6.61 and 21.10?S/cm) in mixed stand and lowest (6.38 and 10.75?S/cm) in pure stand. Organic matter content and total N were highest (2.24 and 0.145%) in plantation stand and lowest (1.65 and 0.112%) in mixed and pure stand, respectively. Available P, exchangeable K and available S were highest (3.65, 98.66 and 17.53ppm) in pure stand and lowest (1.97, 79.49 and 10.25ppm) in plantation stand. In addition, four fungal genera Sclerotium, Rhizoctonia, Pythium and Verticillium were identified in the study area soils. The highest fungal population (entire genus except Verticillium) (colony number/g soil) was found in mixed stand while it was found lowest in pure (Sclerotium ) and plantation stand (Rhizoctonia and Pythium ). There was no significant variation in colony diameter of the fungi among the treatments. Therefore, it can be concluded that better soil health was maintained in natural forest rather than plantation forest.Res. Agric., Livest. Fish.2(1): 17-25, April 2015

EVALUATION OF SOME SOILS IN NORTH WESTERN PARIS OASIS (EGYPT) USING STORIE INDEX AND SYS MODELS

The North Western of Paris Oases represents one of the highest priority areas for future development in the country. The study area is located between longitudes 30 11 34.9 to 30 26 59.4 East and latitudes 24 40 9.3 to 24 51 8.7'' North and covers an area about 123966 feddans. The purpose of this study is to evaluate some soils in north western Paris oasis using Remote Sensing (RS) and Geographic Information System (GIS). For this purpose, Forty-Three soil profiles were described in the field and their representative samples were analyzed. Using geomorpholical map, geological map and visual interpretation of satellite data a physiographic soil map was created to present mapping units of the study area. The area under investigation was classified into three landscape units, i.e. Plain, Dunes and Hills. Soil characteristics of the obtained mapping units were discussed and soil taxonomic unit were identified. Two models of land capability were used to evaluate the soils of study area. According to Storie Index model, the area under investigation was classified into three capability grades reflect the limitation factors, i.e. grade 1 (67.4 %), grade 3 (26.16 %) and grade 6 (6.44 %). on the other hand and according to Sys model the study area was classified into three capability classes, i.e. S2, S3 and N2. The soils of S2 have moderate limitations for agricultural crops, where texture is the main limiting factor (67.4 % of the total area). The main limiting factors of soils of S3 are texture, depth and salinity (26.16 %), while the soils of N2 (6.44 % of the total study area) include sand dunes, rock crops and shallow to very shallow soils. Five crops were selected to assess soil suitability for cultivation in the study area, i.e. wheat, barley, maize, tomato and olive. The results indicated that olive was more suitable for growing in such soils.

Economically Viable STCR Based Nutrient Management on Soybean (Glycine max)

Soybean is the principle oil seed crop in India. Blanket recommendation of fertilizers for soybean over large area irrespective of soil type has lead to indiscriminate use of costly inputs. This has also resulted in imbalanced use of fertilizers and environment related problems. Hence to economize the fertilizer use soil testing should play important role. Therefore, a study on the soil test for improving soybean productivity was performed as a part of mandatory program of Agriculture Science Center, Rewa in Madhya Pradesh (MP) of India. Soils of study area had pH 6.8 to 7.4, EC 0.17 to 0.23 dSm−1, organic carbon 0.33 to 0.71%, available nitrogen 105 to 214 kg/ha, phosphorus 7.30 to 16.80 kg/ha and potassium 173 to 325 kg/ha. Experiment were conducted in rainy season of 2009–10 with two treatments, farmers practice -T1 (50 kg DAP/ha only) and application of fertilizer on the basis of soil test value -T2. Higher grain yield was observed in T2 (1830 kg/ha) than T1 (1180 kg/ha). The maximum increase in soybean yield was noted due to applied fertilizers on the basis of soil test values in T2. The highest Benefit Cost ratio (B:C ratio) 4.05 was registered in T2.

Dynamic behaviour of ground-supported tanks considering fluid-soil-structure interaction (Case study: southern parts of Tehran)

Regarding the importance of the prevention of hazards and adverse environmental impacts in industrial and populated areas such as southern parts of Tehran city, the response of impulsive period ground-supported tanks were assessed. Having considered the study area's soil properties, the response of ground-supported tanks was modelled. Regarding the soil properties of southern parts of Tehran, the soil structure interaction method explained in FEMA 368 revealed that the interactional impulsive period (~T) was greater than non-interactional one (T). In addition, results showed that Poisson's ratio and stiffness ratio (K/Kx) were more effective regarding the response of the interactional period of ground-supported tank systems. According to the achieved results, the liquid mass density effect on impulsive period was as low as the thickness of the ground-supported walls effect. Results showed that wall materials significantly affected the variation within the impulsive period. Generally, concrete materials were shown to be more periodic than steel materials. Overall, in southern parts of Tehran, when the soil fluid structure interaction method was used, the period increased from 1 to up to 3.6 times greater than the normal impulsive period.

Distribution of natural radionuclide along Main Central Thrust in Garhwal Himalaya

Study of natural radionuclide is important to assess the radiation level in a particular area. Radionuclide present in earth's crust is different for different geological areas because of the variety of soil and rocks present in a particular area. In present study, the estimation of natural radionuclides have been carried out along the Main Central Thrust (MCT) in Uttarkashi, Budhakedar, Ukhimath and Healang regions of Garhwal Himalaya, India. The large variations in the radionuclide distribution have been estimated along the Main Central Thrust. The 226Ra, 232Th and 40K contents in MCT area varies from 8 ± 1 Bq.kg−1 to 285 ± 28 Bq.kg−1 with an average of 64 Bq.kg−1, 7 ± 1 Bq.kg−1 to 136 ± 15 Bq.kg−1 with an average 69 Bq.kg−1 and 115 ± 18 Bq.kg−1 to 1588 ± 162 Bq.kg−1 with an average 792 Bq.kg−1, respectively. The radon exhalation rate and radon concentration in the soil of study area varies from 2.20 × 10−5 Bq.kg−1h−1 to 3.2 × 10−5 Bq.kg−1h−1 and 287 Bq/m3 to 417 Bq/m3, respectively. It was observed that the distribution of natural radionuclide in the soil of study area is not uniform and concentrated along geological active region. These values of radionuclide and radon mass exhalation rate may be used as baseline data for further study in the area.

Spatio-temporal Distributions of Tropospheric NO2 over oases in Taklimakan Desert, China

Soil biogenic NO emission is one of the most important sources of atmospheric nitrogen oxides (NOx) worldwide. However, the estimation of soil source, especially in arid areas presents large uncertainties because of the substantial lack of measurements. In this study, we selected the Ruoqiang oases on the southeastern edge of the Taklimakan Desert, China as the study area and applied Ozone Monitoring Instrument (OMI) NO2 retrievals (DOMINO v2.0, 2005–2011) to investigate the spatial distribution and seasonal variations in tropospheric NO2 vertical column density (VCD). High NO2 VCDs were observed over the oases (farmlands and natural vegetation), with the highest value obtained during summer, and lowest during winter. Pulses were observed during spring. We conducted in-situ measurements in June 2011 in Milan oasis and employed ground-based multi-axis differential optical absorption spectroscopy (MAX-DOAS) instruments to validate satellite NO2 retrievals. The findings are as follows: 1) in the study area soil biogenic NO emission is the dominant source of tropospheric NO2; 2) oases (farmlands) are hotspots of tropospheric NO2, and a higher increase in tropospheric NO2 is found in oases from winter to summer; and 3) enhancement of soil biogenic NO emission due to soil managements is predictable. Given the rapid agricultural development in the southern Uygur Autonomous Region of Xinjiang, researches on soil biogenic NO emission and increase in tropospheric NOx should be given more importance.

Bioavailable Trace Elements in Soils around Nnpc Oil Depot Jos, Nigeria.

The concentrations of trace elements (Cu, Zn, Cr, Pb and Cd) in soil samples around NNPC Oil Depot Jos and those of a control area (about a kilometer away from the depot) were investigated by sequential extraction method using Atomic Absorption Spectrometer (AAS). Results obtained showed the concentrations (mg/kg) of Cu, Zn, Cr, Pb and Cd in soil of study area as 22.14, 25.06, 12.41, 14.13 and 9.11 respectively while in control area soil Cu, Zn, Cr, Pb and Cd had concentrations (mg/kg) of 19.69, 22.79, 7.09, 13.53 and 1.24 respectively. The bioavailable components (obtained from exchangeable, water and acid-soluble, and reducible phases) of Cu, Zn, Cr, Pb and Cd were 48.19%, 47.61%, 37.87%, 43.52% and 50.71% of their total concentrations respectively in study area soil while in control area 40.49%, 45.37%, 64.03%, 36.07% and 45.02% were obtained for Cu, Zn, Cr, Pb and Cd respectively. Levels of the trace elements in soils of both study area and control area were observed to be within European Union safe limits except for Cd in the study area. Keywords: Bioavailable fraction, Oil depot, Pollution, Sequential extraction, Trace elements.

Uranium Concentrations measurement for Ground Water and Soil Samples in Al-Najaf/Iraq

In this work, Uranium concentrations in groundwater and soil samples from some areas of Al-Najaf city, Iraq were measured solid state nuclear track detector (CR-39) detector technique. The uranium concentration in groundwater samples was found to vary from (1.617782869±0.04342) μgl −1 to (5.079235843±0.137827) μgl −1 , while in soil samples vary from (0.093558±0.000938) ppm to (0.184325±0.017511) ppm. This study showed that levels of uranium concentration in groundwater and soil of study area of were compared with safe limit values recommended by WHO and UNSCEAR below the safe limit . Keyword: Uranium Concentrations in groundwater, Uranium Concentrations in soil, Najaf Holy city

Evaluation of Landsat TM5 Multispectral Data for Automated Mapping of Surface Soil Texture and Organic Matter in GIS

Mapping fine scale spatial variations of soil properties is important for site specific agriculture. The current study explores the potentials of remote sensing (RS) and geographical information system (GIS) techniques in studying the spatial variability of surface soil attributes. Around 170 surface (0–30 cm) soil samples collected from the soils of Shorkot Tehsil, Punjab, Pakistan were analyzed for surface soil texture and organic matter (O.M.). A multivariate linear regression (MLR) analysis technique was employed to relate surface soil variables with the spectral data from Landsat TM5 satellite. The MLR analysis showed significant (p<0.05) relationship of band 4 and band 6 with silt% (R2 = 0.724) and clay% (R2 = 0.509) while soil O.M. was best modeled using data from band 1, 6 and 7 (R2 = 0.545). The resulting MLR equations were then used for the spatial modeling of these attributes for the entire study area. For developing surface soil texture map, the USDA textural triangle limits for clay% and silt% were used to develop a code in Visual Basic Language in ArcGIS environment. The results showed that ‘sandy clay loam’ was the most abundant textural class in the area followed by ‘sandy loam’ and ‘clay loam’ classes. Moreover, the status of O.M. in the entire study area soils was very poor (<1%). The results indicate that RS and GIS techniques could be successfully used for fine scale mapping of soil texture and O.M. of a larger area.

Short Communication. Recruitment and early growth of Pinus pinaster seedlings over five years after a wildfire in NW Spain

Aim of study: The main aim of this study was to analyse the post-fire recruitment and growth of Pinus pinaster seedlings during the first five years after wildfire and also to analyse the effects of climatic conditions on the survival of P. pinaster seedlingsArea of study: The study area was located in a P. pinaster stand in León province (NW Spain) burned in 1998.Material and Methods: Three sites in the burned area were selected. In each site three permanent transects of 20m x 1m were placed. In each transect, twenty 1m2 sampling units were marked and the number and height of each pine seedlings was recorded at 7, 8, 9, 10, 11, 12 months and 2, 3, 4 and 5 years after the wildfire. The soil of study area is Cambisol.Mean results: Mean Pinus regeneration densities varied between 33.2 seedlings/m2 after 7 months and 6 seedlings/m2 five years after wildfire. In this P. pinaster stand, maximum mortality appeared during the summer months in the first year of regeneration. There was a significant increase in seedling height associated with a decrease in density.Research highlights: The post-fire recruitment is considered enough to ensure good natural Pinus pinaster forest regeneration. In the short term post-fire management strategy in this type of forest could be the remaining branches with cones of burned trees that allow the dissemination of the seeds during the first few years after fire and ensure natural regeneration.Keywords: Fire effects; natural regeneration; León province (NW Spain); seedlings density; growth and survival.

Experiment on Cement Proportion and Mixing Technology for Expansive Soil Modification

Expansive soil has properties such as expanding when encountering water, shrinking and crazing when losing water. Mixing with certain proportion of cement is the main method to modify expansive soil now. According to the field modification experiment on expansive soil which has been done in 3rd section of Changjiang-to-Hanjiang water diversion project, the paper researched the modification effect of different kind of expansive soil that modified by different cement proportion, and modification effect that depends on different size of broken soil mixed in the field. The experiment result shows that, for the medium and weak mixed expansive soil and medium expansive soil in study area, the optimal cement proportion is 4% and 6%. The free swelling ratio of mixed expansive soil can be decreased below 40% by any broken size, and the medium expansive soil can be modified effectively only when the biggest broken size is less than 31.5 mm by controlling the moisture content and improving mixing technology.

Soil mapping and classification: a case study in the Tigray Region, Ethiopia

Soil map is one of the basic tools in any agricultural development planning and generating a digital one is even more effective and more productive for natural resources evaluation. Moreover, remote sensing and GIS have added to soil classification different concept and enforcement. The study aim was to produce digital soil maps for the study area following different classification systems (ST and WRB) and to define the spatial distribution and characteristics all the soil classes in the study area, which will be indispensable for future development planning. This work has been done as a part of the 29 th Course Professional Master in IAO institution, Florence, Italy. The study area was Kilte Awulaelo district in Tigray region, Ethiopia, Which is characterized by different topographies and geomorphologies with different agro ecological conditions. Eleven main soil groups and sixty soil types were identified in the study area. The main soil groups are: Leptosols, Vertisols, Fluvisols, Stagnosols, Kastanozems, Phaeozems, Calcisols, Luvisols, Arenosols, Cambisols and Regosols. Regosols and Cambisols are the dominant soils in the study area which is characteristic soils of rainfed agriculture and land affected by erosion. Using spatial distribution map of each soil group was very helpful to connect soil characteristics with soil forming factors. Lastly, GIS and remote sensing were very effective tools in this study and gave higher value for the final study results.

Design of a Drip Irrigation System for a Pineapple Orchard at the Federal University of Technology Owerri (F.U.T.O) School Farm

The aim of this research paper is to design a drip irrigation system for a Pineapple orchard in the Federal University of Technology Owerri school farm. This work takes into account the preliminary studies of the study area (general relief, topography and soil nature), water quality and quantity assessment (water sample collection, testing and analysis), soil and field analysis (moisture content test, infiltration tests and grain-size analysis) and climatic influence on the area to make resolute conclusions on the parameters required for the design of the drip irrigation system. With reference to the peak consumptive use of pineapple (1.928mm/day) and peak potential evapotranspiration (4.794mm/day) obtained from application of empirical formulas; the drip irrigation system designed comprises of 48 laterals (Inside Diameter of 10mm, 1104 emitters, Discharge of 0.012L/S, and Friction Loss of 13.44m), 1 submain(Inside Diameter of 28mm, Discharge of 0.56L/S and Friction Loss of 3.65m) and 1 mainline (Inside Diameter of 42mm, Discharge of 0.57L/S and Friction Loss of 0.02m) with an actual emission uniformity of 85%.

English

Surface and subsurface soil samples of Muzaffarnagar district were collected to characterize their chemical properties and accordingly to develop optimum land use plan to realize maximum agricultural productivity. The pH value of study area varied from 6.02 to 8.39 and 6.35 to 8.50 for surface and sub surface, respectively, electrical conductivity from 0.069 to 0.390 and 0.073 to 1.10 dSm-1, organic matter content 7.241 to 15.221 and 3.695 to 10.179 g kg-1, available nitrogen (N) 131.53 to 348.97 and 99.32 to 217.44 kg ha-1, Phosphorus (P) 15.67 to 52.61 and 11.17 to 45.40 P2O5 kg ha-1, potassium (K) 79.16 to 436.8 and 47.04 to 399.84 K2O kg ha-1for surface (0-15 cm ) and subsurface soil (15-30 cm). Cationic micronutrients Zn, Cu, Fe and Mn varied from 1.636 to 6.164, 1.024 to 4.282, 0.672 to 5.802 and 0.332 to 2.652, and 113.13 to 11.232, 10.33 to 79.326, 10.272 to 38.572 and 29.578 to 77.882 mg kg-1 in surface (0 -15 cm) and subsurface soil (15-30 cm) respectively. As per soil nutrient index (SNI), the soils of study area were found in low fertility category for nitrogen and medium with respect to phosphorus and potassium. A positive and significant correlation of NPK and micronutrients was found with organic matter content while significant and negative correlations exist between micronutrients and soil pH. Key word: Soil fertility, organic matter, NPK, micronutrients, surface soil, soil nutrient index.