EURASIAN JOURNAL OF SOIL SCIENCE

94-109

Authors: Mulugeta Tufa, Asmare Melese, Wondwosen Tena

Information about effects of land use types on selected soil physical and chemical properties is essential in sustainable utilization of soil resources. Therefore, this study was conducted to evaluate effects of land use types on selected soil physical and chemical properties on Kuyu district, Ethiopia. Totally, 24 composite soil samples were collected from grass, cultivated, forest and grazing lands by two soil depths (0-20 cm and 20-40 cm) with three replications. The two way analysis of variance was used to test the mean differences of the soil physical and chemical properties. The highest mean values of sand and clay were recorded in cultivated and grasslands, respectively. The mean bulk density of the soils ranged from 1.10 and 1.37 g cm-3 and the mean total porosity ranged from 48.2 to 58.7%, which indicated the less soil compaction. The pH ranged from 7.68 to 8.00 while the mean values of OM ranged from 3.15 to 5.02%. However, the mean values of total N ranged from 0.18 to 0.26%. The mean value of available P ranged from 1.26 to 5.37 mg kg-1, which implies that high deficiency of available P in the study area. The exchangeable basic cations and CEC values were within high to very high ranges in all land use types. Conversion of land use types from one to another has adverse effects on soil properties, especially overgrazing and cultivation of deforested land. Therefore, the proper soil and water conservation practice are important in the study area to enhance soil fertility and crop productivity.

118-130

Authors: Alemu Lelago, Tadele Buraka

The objectives of this study were to classify the soils of Tembaro district, and to identify its potentials for crop production. Five pits representing a pedon each were opened and profile in each pit was described for its morphological, physical and chemical characteristics according to standard procedures. A total of 20 disturbed soil samples and 16 core ring samples were collected from five representative profiles. The samples were analyzed in the laboratory for texture, BD, FC, PWP, Soil pH, EC, OC, TN, av.P, av.K, exchangeable bases, free and active iron and CEC. The results showed that the proportions of soil separates varied among profile and depth however, soils were all in clay textural class. The BD varied from 1.02 in the surface profile 1 to 1.25 g.cm-3 in the profile 3. Soil pH ranged from 6.8 to 5.4 in the surface horizons of all profiles with further decrease with depth indicating that the soils in the watershed are slightly acidic to moderately acidic. The OM and TN contents ranged from 2.90 to 5.43 and 0.23 to 0.45% in the surface horizon and they were in the low, low to medium and high categories respectively. The corresponding values for the remaining subsoil horizons were in the low categories. In all cases the contents of these parameters decreased considerably with depths. Available P was below critical values for all profiles and depths except for profiles 1 and 4. Exchangeable K was above critical value in all profiles with increasing trend along with depth of all profiles. Exchangeable Mg varied from 2.47 in surface horizon of profile 3 to 3.98 cmolc kg-1 in the surface horizons of profile 4 and increased with depth in all profiles except in profile 1. The observation with exchangeable K and Mg implies that there is leaching phenomenon in the study area. Ca ranged from 4. 35 cmolc kg -1 in profile 5 to 16.50 cmolc kg -1 in profile 1 with inconsistent trend with depth. The CEC from 18.22 cmolc kg -1 soil in surface horizon of profile 5 to 27.43 cmolc kg-1 soil in the surface horizons of profile 1 indicating they are in the medium to high ranges. But inconsistent trend in CEC distribution was observed with depth in all profiles. Based on the data collected from profile description study and soil physicochemical analytical data and according to FAO-WRD soil classification legend, the soil at Ambukuna watershed were classified as Haplic Nitisols (Endoeutric, humic), Haplic Nitisols (Hypereutric, humic), Haplic Nitisols (Endoeutric) and Haplic Nitisols (Epidystric, Humic). Most of the soil physical and some of the chemical characteristics studied could be ranked as good indicating that the area has high potential for agricultural production.

144-151

Authors: Md. Shahadat Hossain, GKM Mustafizur Rhman, Md. Saiful Alam, HA Mashuk, Md. Mizanur Rahman

Soil salinity expressed by electrical conductivity is a threat to crop production. The study aims were to establish relationships of electrical conductivity with its relevant soil properties, and analyze variability of soil salinity in the coastal zone of Bangladesh. A total of 150 geo-referenced saline soil samples from three coastal districts (Khulna, Satkhira and Bhola) of Bangladesh were analyzed for electrical conductivity of saturated paste extract (ECe), salt cations and other soil properties related to salinity. Statistical and geostatistical analyses were done as required. Moderate to strong significant regression relationships (R2=0.42 to 0.94) were found between ECe and salt cations (ECe=43.12*Na2-46.36*Na+13.97; ECe=12.26*K-2.5;ECe=1.16*Ca-1.97; ECe=0.32*Mg2-1.60*Mg+3.53) of the soils. On the contrary, weak relationships (R2=0.05 to 0.21) were found between ECe and other soil properties (ECe=4.41*organic carbon-0.56; ECe=-1.71*Txw (soil texture)+3.98;ECe=0.35*cation exchange capacity-1.98; ECe=0.06*specific surface area-0.55). Khulna soils (CV=65.99%) showed lower statistical variations while Satkhira (CV=97%) and Bhola (CV=105%) soils showed higher statistical variations for ECe. In contrast, Khulna, Satkhira and Bhola soils showed strong, moderate and weak spatial dependency for ECe, respectively. Interpolated spatial distribution maps of ECe showed variations in individual districts of study areas. The findings would assist soil scientists or farm managers to understand and/or manage saline soils, specially the soils of coastal zone of Bangladesh.

159-166

Authors: M. Amjad Qureshi, Haroon Shahzad, M. Sajjad Saeed, Sana Ullah, M. Asif Ali, Fakhar Mujeeb, M.A. Anjum

Legumes compensate mineral fertilizer by fixing nitrogen due to the specialized structures i.e. nodules by Rhizobium species. Literature revealed that legumes fixed nitrogen due to Rhizobium inoculation from 50-300 kg NPK ha-1 year-1. Rhizobium besides nitrogen fixation, solubilized phosphates, produced growth hormones and due to its root colonizing ability improved the growth and yield of non-legumes also and performed as plant growth promoting rhizobacteria (PGPR). Study was conducted to assess the relative efficiency of Rhizobium species for the growth and yield of cotton. Different isolates of five species of Rhizobium species responsible for different nodule formation in legumes were assessed for the auxin biosynthesis potential as IAA equivalents and isolates having higher values for IAA equivalents were used for experimentation. Results revealed that isolates of Rhizobium species improved the growth and physiological parameters of cotton. Higher values were root/shoot length and mass were observed with Rhizobium species of berseem (Br5). Bacterial inoculation with isolate (Br5) produced 60.94, 64.40 g shoot/root mass that is 16.70 and 23.80 % higher than control and percent increase improvements of cotton shoot/root length with Br5 i.e. 18.3, 24.8 % higher than that of control. Higher values of IAA equivalents were observed in root/shoot content of cotton with isolate of Br5. Bacterial inoculation improved the plant height, boll weight, number of bolls plant-1 and seed cotton yield with Br5 inoculation. The chlorophyll content, photosynthetic rate, transpiration rate and photo active radiation were also higher in the inoculated treatments. Results of present study clearly demonstrated that different isolates of Rhizobium species improved the growth and yield parameters of cotton and thus Rhizobium sp can be effectively utilized as bacterial inoculants in non-legumes.

176-183

Authors: Belgin Doğan, Coşkun Gülser

This study was carried out to determine the suitable classification of soil quality for vineyard fields of Akçaköy, Çatalca, Efemçukuru, Görece and Yeniköy villages in Menderes district of Izmir-Turkey. In vineyard fields, soil pH gave a positive relation with Ca and significant negative relations with P, Fe, Mn and Zn contents. Soil organic matter (OM) content had significant positive relations with EC, P, Fe, Mn and Zn and significant negative relations with bulk density and CaCO3 content. Soil quality index values for the vineyard fields varied between 0.38 and 0.85 with a mean of 0.57. Only one of the 28 soil samples taken from different vineyard fields was found in very suitable (S1:1.00-0.75) class, 8 in suitable (S2:0.75-060), 12 in marginal suitable (S3:0.60-0.50) and 7 in non-suitable (N:<0.50) class according to the soil quality index (SQI). Restricting soil factors for vine growth in the fields classified in S2 and S3 classes generally became low pH, low organic matter (OM), P, Fe, Mn, Cu, Mg and K contents than that of suggested levels. In addition to restring factors in S2 and S3 classes, physical properties in soils classified in N class were lower than suggested levels. The SQI values showed significant positive relations with grape yield, soil OM, P, K, Fe, Cu, Mn, Zn contents and significant negative relations with soil pH, exch. Ca and CaCO3 contents. The grape yields had also positive relations with soil OM, Fe, Mn, Zn contents and negative correlations with soil pH and CaCO3 content. Soil quality in a vineyard field should be assessed to reach successful sustainable and precision agricultural practices for high crop production.

1 - 10

Authors: Siti Wardah Zaidun , Mohamadu Boyie Jalloh , Azwan Awang , Lum Mok Sam , Normah Awang Besar , Baba Musta , Osumanu Haruna Ahmed , Latifah Omar

Increase in cost of chemical fertilizers encourages the use of soil amendments such as biochar and zeolites to improve soil fertility. In this study, biochar produced from empty fruit bunch-palm oil mill effluent (EFB-POME) and clinoptilolite zeolite were used as soil amendments to improve soil fertility. The field experiment was carried out for two planting cycles to determine the effects of different rates of EFB POME biochar (0, 10, and 20 t ha-1), clinoptilolite zeolite (0, 1.25, and 2.5 t ha-1), and urea (60 and 120 kg ha-1) on selected soil chemical properties of Tanjung Lipat (Typic Paleudults). Biochar produced from EFB-POME increase soil total N, P, K, Ca, and Mg. The higher soil total N, P, K, Ca, and Mg could be related to the increase in soil pH, cation exchange capacity, and total organic carbon in soil with EFB-POME biochar but not with clinoptilolite zeolite. Thus, EFB-POME biochar was more suitable to be used in a tropical soil (Typic Paleudults) compared to clinoptilolite zeolite for improving the selected soil pH, CEC, TOC and available P, K, Ca and Mg.

17 - 26

Authors: Muhammad Irfan , Muhammad Abbas , Javaid Ahmed Shah , Nizamuddin Depar , Muhammad Yousuf Memon , Niaz Ali Sial

Most of the arable soils in Pakistan are deficient in plant available phosphorus (P) and boron (B) primarily due to alkaline and calcareous nature along with low organic matter. A combined deficiency of these nutrients may intensify the plant growth suppression by reducing their efficient utilization. A pot experiment was conducted to investigate the interactive effect of P and B on growth, nutrient accumulation and grain yield of wheat grown on calcareous soil. Wheat crop was grown at three P levels (45, 90 and 135 kg P ha-1) in combination with five B levels (0, 0.5, 1.0, 1.5 and 2.0 kg B ha-1) following completely randomized design. The results revealed that yield and yield related attributes increased linearly with the addition of B at each P level. Nonetheless, the significant interactive effect of both nutrients was most pronounced in the treatment having 90 kg P ha-1 and 1.5 kg B ha-1. Applied B rates resulted in relatively higher P concentration in grains and straw at P level of 90 kg ha-1 contrarily to 45 and 135 kg P ha-1. The B concentration in grains and straw increased with corresponding addition of B at each P level but at variable rate, with the maximum response at higher P level. Grain and straw yield illustrated positive correlation with total P uptake (R2 = 0.96 and 0.81) and total B uptake (R2 = 0.95 and 0.70) respectively. Likewise, positive correlation (R2 = 0.94) between total P uptake and total B uptake under combined application of P and B indicated their synergistic relationship. Overall, the treatment combination of 90 kg P ha-1 with 1.5 kg B ha-1 was found as the most suitable dose for better plant growth, nutrient accumulation and grain yield of wheat.

35 - 43

Authors: Orhan Dengiz , Fikret Saygın , Ali İmamoğlu

The main objectives of the current study are i) to estimate SOC in different soil depths and to generate their spatial distribution maps, ii) to assess relationship between variation of different soil types and SOC density, iii) to determine effects of land cover types on SOC in Inebolu Watershed located in sub-humid terrestrial ecosystem. In order to determine land cover types of the study area, aster satellite image was used and five main land cover types that are bare land, sparsely vegetated area, broadleaved forest area, mixed forest area and needleleaved forest area were classified. Results indicated that soil types and land cover were two crucial influencing factors for spatial variation of SOC density. It was determined that SOC density of soil types, Vertic Haplustept (12.93 kg.m-2) was significantly higher than other soil subgroups. In this case, it can be said that main reasons of this result are indicated as soil profile depth and pedological development. In addition, when comparing the two main factors, land cover explained more of the SOC density variability and was the main controlling factor in the surface; in the subsurface, not only land cover types but also some properties of soil types such as texture, genetic horizons, soil depth have an important role on SOC density. On the other hand, it can be conclude that the combination of the soil type and land cover was a dramatically better predictor of SOC density.

54 - 59

Authors: Taiki Mori , Ryota Aoyagi

We aimed to test if anthropogenic P input into ecosystems reduces microbial resource allocation to acquire N (and alleviate N shortage if any) because microbes no longer produce N-rich phosphatase for P acquisition. Literatures reporting the effect of P fertilization on C-acquiring (β-1,4-glucosidase, BG) and N-acquiring (β-1,4-N-acetylglucosaminidase, NAG, which also acquires C) enzymes were collected and synthesized. We predicted that P addition elevates BG:NAG especially in P-poor ecosystems because P addition alleviates N shortage and reduces the microbial resource allocation to acquire N relative to C. The synthesized data demonstrated that P fertilization occasionally reduced BG:NAG, which is inconsistent with the prediction. However, this might not mean that the initial hypothesis was rejected. Stimulated microbial activity and turnover by P fertilization could have caused microbes depend the C sources more on chitin (and peptidoglycan) compared with on cellulose because chitin (and peptidoglycan) is a main component of microbial body and re-provided through microbial turnover. The changes in C resources accompanied by the altered P availability may have largely influenced BG:NAG, masking the role of BG:NAG for indicating microbial resource allocation to C and N acquisitions.

73 - 82

Authors: Julius Romiluyi Orimoloye , Oluwatosin Abimbola Egbinola

A study was carried out to evaluate the suitability of some Peri-urban soils in Lagos state for arable crop production. Six pedons classified as Alagba (Rhodic Hapludult), Dodokindo (Plinthic Kandiudult), Idesan (Typic Endoaquept), Owode (Typic Kandiudult), Atan (Fluvaquentic Endoaquept) and Pakoto (Plinthic Kandiudult) Series identified at two study sites located at Igbokuta and Ibomwon communities in Ikorodu and Epe Local Government Areas of Lagos state were evaluated. The land use potentials for maize, cassava and leafy vegetables (Amaranth family) were assessed following the conventional non-parametric and the parametric (square root) methods of land suitability evaluation according to the revised FAO framework. All the pedons were rated as marginally suitable (S3) for maize except Idesan and Owode Series that made up 2.53% and 34.74% of the total area respectively, which were rated moderately suitable (S2). With respect to cassava and leafy vegetables, all the pedons were rated marginally suitable (S3) except Atan Series occupying 19.71 % of the total area, that was rated non-suitable (N1). The major limitations to sustainable crop production in all pedons were low nutrient supply (N, K, P and cations) coupled with high soil acidity (pH of between 3.9 and 5.8). In addition to this, Idesan and Atan series also have waterlogging problem hence may not be used for cultivating the afore-mentioned crops, but could be used for swamp rice. With appropriate liming, soil fertility management and proper drainage, most of the pedons may be rated as being moderately suitable (S2) for the cultivation of these crops. As a peri-urban area with high demand for agricultural products, year-round cropping with irrigation facilities is quite promising in most of the pedons studied.

284 - 291

Authors: Imane Achkouk , Saida Aarab , Amin Laglaoui , Mohammed Bakkali , Abdelhay Arakrak

Utilization of plant growth promoting rhizobacteria (PGPR) is now gradually increasing in agriculture and offers an attractive way to replace chemical fertilizers, pesticides, and supplements. This study was conducted with a view to isolate bacteria from the rhizosphere of the legume Lotus creticus (L. creticus) and to assess their plant growth promoting functional potentialities. A total of 113 rhizobacteria was isolated from the rhizosphere of L. creticus and were tested for their capacity of solubilizing tricalcium phosphate (TCP) on Pikovskaya (PVK) solid medium. Out of 29 phosphate solubilizing bacteria (PSB), 5 isolates were selected for their solubilization diameters (between 0.6 and 1.5 cm). These isolates were characterized for plant growth promoting (PGP) traits. The results showed that the highest concentration of indole acetic acid (IAA) was produced by LCR33 (19.08 ± 0.96 mg L-1). All 5 isolates could produce hydrogen cyanide (HCN), siderophores, ammonia and amino-cyclopropane carboxylate (ACC) deaminase. The isolates were evaluated for TCP solubilizing quantitative assay in PVK liquid medium. The concentrations of solubilized P were between 43.34±0.18 mg L-1 and 173.57±0.77 mg L-1. This solubilization was accompanied by a pH decrease of the culture media from 7 to 4.06. Furthermore, the 5 selected PSB were tested in vitro for antagonism against phytopathogenic fungus Fusarium oxysporum. In fact, all the PSB, were capable of inhibiting its growth and the highest percentages of inhibition were obtained for LCP27 and LCR33 (48.15±0.99% and 40.74±0.45%). Also, the effect of these 2 PSB on growth of L. creticus plants was investigated under greenhouse conditions. Significant increases were obtained for shoot and root length and dry and fresh matter production of plants as compared to the uninoculated control. These PSB could be recommended as biofertilizers for contributing to the rehabilitation of degraded soils.

300 - 307

Authors: Alexey Belenkov , Mikhail Mazirov , Valeria Arefieva

The questions of inserting and implementing the different methods of basic soil treatment in the different crop plantings in the conditions of steppe zone in Nizhnee Povolzhye and Central Part of Non-chernozem Belt of the Russian Federation are analyzed. Systemize and complex research of the above questions are caused by multivalued opinions of agrarian scientists that are involved in the practical aspects of agrarian production towards them. On the results of long term researches is defined that the most effective and practice in cereal crop rotations are the basic soil management systems combining the different methods of tillage, mini-till and no-till soil treatment along with usage of modern machines and aggregates. In the conditions of field experiment at Centre of Precision Farming of Russian State Agrarian University - Moscow Timiryazev Agricultural Academy, along with the others, the tasks on economic efficiency and ecological safety that are the basis of precision farming concept are being solved.

318 - 325

Authors: Mojtaba Yahyaabadi , Amir Hossein Hamidian , Sohrab Ashrafi

We investigated the dynamics of different earthworm species through the soil profile, which had received short-term amendments of either organic or inorganic fertilizer in an orchard during the spring of 2016. Earthworm populations were sampled at two consecutive depths of soil on 20 and 60 days after addition of fertilizers. The dominant earthworm species were Eisenia fetida (Savigny, 1826), Dendrobaena veneta (Rosa, 1886), Dendrobaena hortensis (Michaelsen, 1890), Lumbricus terrestris (Linnaeus, 1758) and Aporrectodea longa (Ude, 1885). Seven different types of fertilizers including Urea, Ammonium sulfate (AS), Diammonium phosphate (DAP), Solupotas, NPK (15-5-25), (NPK+OM) and organic manure (OM) as experimental treatments were studied. Fluctuations in earthworm numbers and biomass were attributed to changes in time and depth of sampling, in addition to the types of fertilizers. The results of the means comparison showed that on the 20th day, at 0-20 cm soil depth, E. fetida species abundance was decreased significantly in AS and Urea treatments compared to the control plot (p˂0.05). We highlighted that from epigeic group, D. hortensis species had a better chance to survive and its population in AS treatment was more than that of Urea treatment. Results also showed that the anecic L. terrestris, had a greater tolerance to chemical fertilizers compared to the A. Longa species. The results of this study outline more clear horizons in managing the use of chemical fertilizers while simultaneously maintaining the biodiversity of soil organisms.

337 - 345

Authors: Olateju Dolapo Adeyolanu , Kayode Stephen Are , Ayodele Olumide Adelana , Gabriel Akinboye Oluwatosin , Oluwabunmi Aderonke Denton , Olufunmilayo Titilayo Ande , Olugbenga Egbetokun , Lucia Ogunsumi , James Alabi Adediran

To successfully manage soil quality for sustainable crop production, there is need to identify issues affecting it. These are problems facing the capacity of soil to perform its functions and thus reducing its productivity. In addition, the similarities and differences between farmers’ perception of soil quality issues and that of soil scientist are very pertinent. This study, which was carried out at Itapaji watershed in Ikole local government area of Ekiti state, aims at identifying soil quality issues using participatory approach and conventional method. Diagnostic survey was carried out using participatory approach involving farmers’ judgement using questionaires. . The resultswere analysed to identify the soil quality issues from farmers’ perspectives. For conventional method, major soil types were identified and soil quality issues were identified using soil management assessment framework. The relationship between the soil issues from farmers’ interview and soil analysis were established by correlation analysis at α0.05. Soil quality issues identified by farmers are soil compaction, low soil fertility, termite infestation, crop wilt, hardpan formation, erosion, poor drainage and land use intensification. Low soil fertility is the most prominent with about 36.2 % impact on crop production in the watershed. Conventionally from soil analysis, CEC and organic matter are low which indicate low soil fertility; there is high acidity, shallow soil depth with presence of plinthite and hard pan. The farmers’ perception of soil quality and that of soil scientists correlate well (r = 0.70). There is therefore need for promotion of farmers’ participation by providing a forum for articulation of their opinions in mitigating low soil quality.

355 - 364

Authors: Munir Ahmad, Dost Muhammad , Maria Mussarat , Muhammad Naseer , Muhammad A. Khan , Abid A. Khan , Muhammad Izhar Shafi

Soil samples at 0-20 cm depth were collected from major crop areas of Hindukush mountainous range, District Chitral, extreme Northwestern Pakistan, during April 2014 to assess their physico-chemical properties and spatial distribution pattern. 103 soil samples were analyzed and maps were created by geostatistical technique of inverse distance weighting and kriging techniques using GIS and GS win-7 computer software. The soil texture ranged from silt loam to dominantly sandy loam, slightly acidic to alkaline and moderate to highly calcareous but with no salinity indication. Soil organic matter was higher than 2 % in about 75 % of samples. Soil pH, EC and lime showed slight dependence on each other with r values from 0.4 to 0.5 while OM varied independently as indicated by their lower correlation values. Semivariogram analysis showed that soil pH, lime, OM had strong spatial dependence (nugget-sill ratio, <25%) while silt, sand, EC had moderately (nugget-sill ratio, 25-75%) and clay had weakly distributed in the area. Linear, Gaussian and exponential models were used for different soil parameter based on nugget, mean prediction error and root mean square standardize prediction error values and maps were developed through extension techniques to cover all the area outside the sampling points.

192 - 202

Authors: Melis Cercioglu

Soil pore parameters are important for water infiltration into the soil and transport within the soil. The aim of this study was to compare influences of agroecosystems on soil pore characteristics (number of pores, macropores, coarse mesopores, porosity, macroporosity, coarse mesoporosity, pore circularity) using computed tomography (CT). This experiment was carried out four different agroecosystem field [Tucker Prairie (TP): native prairie, Prairie Fork (PF): restored prairie, Conservation Reserve Program (CRP), and row crop (RC): corn/soybean rotation] in Missouri state of United States during the year of 2017. Undisturbed soil samples were collected at four soil depths (0-10, 10-20, 20-30, and 30-40 cm) from each treatment with three replications. Five scan images from each sample were acquired using a X-ray CT scanner with 0.19 by 0.19 mm pixel resolution with 0.5 mm slice thickness and analyzed with Image-J. TP, PF, CRP, and RC treatments had 195, 88, 112, and 49 pores on a 2500 mm2 area, respectively across all the depths. Soil under TP and CRP treatment had significantly higher porosity (0.046 m3 m-3, 0.046 m3 m-3), and macroporosity (0.036 m3 m-3, 0.041 m3 m-3) values than other treatments. The CT-measured number of macropores (>1000 μm diam.) were 5 times higher for TP when compared with RC treatment. The CT-measured pore circularity values were lower for CRP and RC treatments. CT-measured number of coarse mesopores, and mesoporosity were significantly greater under TP treatment. Results show that native prairie can improve soil pore parameters.

213 - 223

Authors: Salah Hassanien Abd El-Aziz, Mohsen A. Gameh, Ahmed Ghallab, Ibrahim H. Bakeer

Sohag governorate is a narrow long strip of a cultivated valley located in upper Egypt. Groundwater and soil samples were collected along the Nile river, starting form the southern border to the northern border of Sohag governorate to assess the groundwater quality and soil salinity between 1991 and 2006. The obtained data reveal that the electrical conductivity of well waters (ECw) was classified to four classes (250-750, 750-2250, 2250-5000 and greater than 5000 μS/cm). The results showed an increase in the groundwater salinity within 15 years, especially in the first class where it increased from 9% in 1991 to 14% in 2006 but it raised from 17% in 1991 to 37% in 2006 for the third class. The surface and subsurface soil layers showed an increase trend in the soil salinity from 1991 to 2006. The soil salinity increased with depth from 1991 to 2006. The groundwater pH values changed due to the changes in their salt content from 1991 to 2006. The pH values of the surface and subsurface soil samples also changed from 1991 to 2006 that may be due to the changes in salt content of well waters. Cations and anions of the groundwater increased from 1991 to 2006. The groundwater SAR decreased for the first class (0-10) from 89 % in 1991 to 83 % in 2006 but increased for the second class (>10) from 11% in 1991 to 17% in 2006. The groundwater RSC for the first and third classes changed from 91 and 3 %, respectively, in 1991 to 83 and 11%, respectively, in 2006. The increase in the high class of RSC may limit the use of these waters in irrigation. Thus, the irrigation with such water might affect the permeability of soil and cause infiltration problems.

230 - 237

Authors: Selvam Ramarajan, Sugumar Susila, Duraisamy Tamilselvi, Muthunarayanan Vasanthy

We aim to quantify heavy metals in tea powders (packed and used), tea waste disposal sites and in the soil away from the site of disposal and to isolate the bacteria from both the soil sample. Atomic Absorption Spectrometer (AAS) analysis revealed chromium in the samples collected from Thanjavur (0.12 mg/kg) and Tiruchirappalli (4.77 mg/kg). The quantity of Copper was between 0.14 mg/kg and 0.97 mg/kg Namakkal and Erode samples respectively. We also found trace levels of other heavy metals. The spatial map distribution patterns of selected Physico-chemical parameters like pH, EC, Alkalinity, Total carbon in the disposal sites were presented. Some of the metal-intolerant strains isolated from the disposal sites became resistant. Further investigation would unravel the possible mechanism behind Chromium reduction by the selected isolates.

251 - 256

Authors: Maneyahilishal Tefera, Ftsum Gebreyohannes, Mekala Saraswathi

The purpose of this study was to assess physicochemical parameter and heavy metal concentration of the soil in and around Robe town, Bale zone, Ethiopia. Seven soil samples (three from dump sites and four from farm lands) were collected and analyzed through different methods for analyzing the physicochemical parameters like, pH Sand/Silt/Clay Content, MC, OM. and the heavy metals including Cr, Cd, Cu, Fe, Zn and Pb, were investigated using Flame atomic absorption spectrophotometer (FAAS). The analyzed result of all sites revealed that, high moisture content % (14.83 ± 2.57to 19.96 ± 0.72), pH slightly acidic except S2 which is slightly basic, (5.77 ± 0.08 to 7.60 ± 0.33),high organic matter % (13.83 ± 0.49 to 16.60 ± 0.90), sand % (53.00 ± 4.51 to 65.33 ± 2.42), silt % (19.33 ± 1.03 to 24.84 ± 4.62), clay % (11.33 ± 1.03 to 19.50 ± 2.50) sandy nature of soil were observed and the concentration of heavy metals such as: Cr (32.53 ± 3.51 to 41.81 ± 1.06) ppm, Cd (0.57 ± 0.21 to 0.93 ± 0.24) ppm, Cu (26.54 ± 0.68 to 37.44 ± 2.72) ppm, Zn (66.98 ± 1.09 to 170.48 ± 1.51) ppm Fe (33483.55 ± 1470.02 to 49012.18 ± 2692.20) ppm and Pb (18.04 ± 0.37 to 20.77±0.46) ppm were obtained. The results showed that all of the assessed heavy metals below maximum permissible limit except Fe, which is above maximum permissible limit that recommended by Ewers, Based on the results obtained from the study the level of metals concentrations safe for agricultural activities. But different measures must be taken to minimize additional soil pollution.

261 - 272

Authors: Naveen Ch. Pandey, Lalit M. Tewari, G.C. Joshi, Brij M. Upreti

Soil is one of the basic natural resources on which all forms of terrestrial life co-exist. The soils of three forest types i.e., banj-oak (Quercus leucotrichophora A. Camus) chir-pine (Pinus roxburghii Sargent) and sal (Shorea robusta Gaertn. f.) of Betalghat block, Nainital District, (Kumaun Himalaya). Soils were drawn from three depths viz. 0-10 cm, 11-20 cm, 21-30 cm. The present study were studied resulted to soil physico-chemical properties i.e. maximum soil texture (sand 34.30 %, silt 57.21 % and clay 33.23 %), soil moisture (12.6 %), bulk density (1.43 g.cm-3), porosity (52.06%), water holding capacity (69.27%) and the maximum values of chemical analysis i.e. pH (6.80), total carbon (3.82 %), organic matter (6.57 %), total nitrogen (0.36 %), available potassium (267 mg/kg) and available phosphorous (62 mg/kg). Banj-oak forest shows rich physical properties followed by sal and chir-pine forest while chir-pine forest shows rich chemical properties in compared to sal and banj-oak forest.

93-102

Authors: Ali Keshavarzi, Henry Oppong Tuffour, Ali Bagherzadeh, Duraisamy Vasu

The present study was conducted to explore the fractal behavior and establish fractal dimensions of soil physical and chemical properties (i.e., sand, silt, and clay contents, bulk density, degree of moisture saturation, pH, organic carbon content, total nitrogen, available phosphorus, and available potassium) to characterize their spatial patterns. Soil samples were collected from 0-30 (surface) and 30-60 cm (subsurface) depths from an agricultural field, Mashhad Plain, Northeast Iran. Descriptive statistics and fractal analysis were used to describe the extent and form of variability. Spatial patterns of the soil properties were estimated using GS+ 10.0 software. Soil properties showed low to high variations in both surface and subsurface layers across the field, where bulk density and pH being the most reliable soil physical and chemical properties in the study area. The variability was high (CV > 35%) for total N, available P, available K and organic carbon in both surface and subsurface soils and it could be attributed to management practices and micro-topographical variations as these are the dynamic properties of soil. The fractal dimension (D) values of soil physical properties ranged from 1.398 to 1.913 at the surface, and from 1.874 to 1.934 at the subsurface indicating both short and long range variations. The D values for the chemical properties ranged from 1.331 to 1.975, and 1.148 to 1.990 in the surface and subsurface layers, respectively. The results showed that fractal analysis could be employed to effectively describe the structure of soil heterogeneity in spatial scale for effective agricultural and environmental management of soil.

109-114

Authors: Rosana Faria Vieira, Nilza Patrícia Ramos

The aim of this study was to evaluate the response of chemical parameters and microbiological processes related to the nitrogen (N) cycling in an area cultivated with sugarcane (SC), as compared to the native forest area (NF), considered as the reference. The pH value, the total C (Ctot), N (Ntot) contents, the P, K, Ca, Mg, Zn, Mn, B and Cu contents, the labile carbon (LC) content, cation exchange capacity (CEC), microbial biomass N (Nmic), potentially mineralizable nitrogen (PMN) and the urease activity (UA) were determined in soil samples taken at depths of 0-10 and 10-20 cm. Most of the chemical properties were higher in the NF soil at both depths, except for Ctot, Ntot and the total K content, which did not present significant differences between the areas at the deeper level. All microbiological processes were higher in the NF soil and showed positive correlations with the total Cu and B contents, demonstrating the importance of these nutrients in the biological N cycling. The higher values obtained for almost all parameters in the NF soil attest to the need for constant monitoring of areas cultivated with sugarcane in order to avoid the adverse effects of soil degradation. The results obtained between the areas, in relation to N cycling processes also demonstrated the suitability of using them as reliable indicators of soil quality.

121-132

Authors: Audrey Asap, Ahmed Osumanu Haruna, Nik Muhamad Ab. Majid, Maru Ali

The reaction of H2PO42- and HPO4- with Al and Fe in acid soils to form a precipitate reduces P availability. Chicken litter biochar has been used to improve soil P availability for maize production but with limited information on optimum rates of biochar and Triple Superphosphate (TSP) to increase P availability. This study determined the optimum amount of chicken litter biochar and TSP that could increase P availability. Different rates of chicken litter biochar and TSP were evaluated in an incubation study for 30, 60, and 90 days. Selected soil chemical properties before and after incubation were determined using standard procedures. Soil pH, total P, available P, and water soluble P increased in treatments with 75% and 50% biochar. Total acidity, exchangeable Al3+, and Fe2+ were significantly reduced by the chicken litter biochar. The chicken litter biochar also increased soil CEC and exchangeable cations (K, Ca, Mg and Na). The use of 75% and 50% of 5 t ha-1 biochar with 25% TSP of the existing recommendation can be used to increase P availability whilst minimizing soil Al and Fe content. This rates can be used to optimize chicken litter biochar and TSP use in acid soils for crop production especially maize and short term vegetables.

151-166

Authors: Endalkachew Fekadu, Kibebew Kibret, Bobe Bedadi, Asmare Melese

Soil resource information is vital for sound land use planning and sustainable fertility management. This study was carried out with the objective of characterizing and classifying soils of Yikalo Subwatershed at Lay Gayint district, Northwestern Ethiopia. Representative soil pedons were opened along topographic positions and described on genetic horizon basis in the field for their morphological characteristics and analyzed in the laboratory for selected physical and chemical soil properties. The soils were classified following the FAO (2014). The results revealed the presence of variations in the selected morphological properties within a pedon and along the topographic positions. Soils differed in reaction from 4.57 to 6.42. On the surface horizons of the soil pedons, available P content varied from 0.21 to 3.25 mg kg-1, while exchangeable acidity ranged from 0.17 to 3.65 cmolc kg-1 soil. There was no consistent trend for cation exchange capacity (CEC) and PBS (percent base saturation) with soil depth and topographic positions. The soils in Yikalo Subwatershed were classified as Hyperdystric Cambisols (Humic), Haplic Alisols (Humic), Cambic Umbrisols (Colluvic), Haplic Luvisols (Epidystric), and Pellic Vertisols (Mesotrophic). Optimum rates of organic and inorganic amendments should be applied to reduce the level of soil acidity, and improve the fertility level of the soils for better crop production and productivity.

181-186

Authors: Gani Oladejo Kolawole, Tunmise Moses Haastrup, Timothy Ipoola Olabiyi

Poor soil fertility and nematodes limit yam tuber yield and quality. Arbuscular mycorrhizal fungi (AMF) and fertilizers may suppress nematodes and improve yam productivity. We evaluated the extent AMF and fertilizer suppressed nematodes and improved yam performance. Tuber weight, mycorrhizal colonization of roots and nematode populations were evaluated with eight treatments; Control (No amendments), 90-50-75, kg N- P2O5-K2O ha-1 (NPK), (AMF) (2g/kg soil), nematodes (5000 juvenile/pot), and their combinations. Tuber weight was higher in NPK+AMF and NPK+nematode treatments than AMF+nematode. NPK+AMF improved tuber weight by 17.5% and 32% compared with sole NPK or AMF respectively. Compared with control, nematodes did not reduce tuber weight but, AMF+nematode reduced it by 49.4%. NPK reduced AMF colonization of roots and reduced nematode population on tuber, in roots and soil by 34%, 42.6% and 41% respectively. NPK+AMF treatment was superior to either NPK or AMF in improving tuber yield while NPK was superior to AMF in suppressing nematodes in roots, soil, and tuber.