The hypothesis is that incorporating saline soil with biochar or compost reduces the deteriorating effects of salinity. The pot experiment was irrigated with waters with different salinities (4.5 and 9 dS m-1) and a silty clay soil in pots was thoroughly mixed with 1.5% w/w of biochar, 1.5% w/w of municipal solid waste compost and the mixtures of 0.5 × 0.5% w/w of the two mentioned substances. Irrigation was provided to realize 0.15 leaching fractions for equilibrating the soil salinity. Soil and plants were analysed after two months (T1) and three months (T2) after sowing. Saline irrigation water decreased SAR (~45%) and SOC (~5.5%), respectively for T2 compared with T1. The biochar treatment reduced the amount of ECe in T1 and T2. Both irrigating with saline water and amendments greatly changed the amount of leaf water potential (LWP), chlorophyll and proline leaf. LWP and proline were increased by 17 and 76%, respectively, with increasing irrigation water salinity, while the leaf chlorophyll content was significantly decreased (~52%). The overall finding was that incorporating the saline soil of the region with biochar showed more potential to enhance soil properties and sorghum production.
Rhizophosphate bacteria as biofertilizers is a low-cost and environment-friendly fertilizer for improving the nutrients status and fertilizers' efficiency on degraded agricultural or marginal soils. In this study, the characteristic and performance of selected rhizophosphate bacteria producing phytohormone and organic acid producers was investigated. Soils samples for beneficial rhizobacteria were taken from five maize ( Zea mays L.) production area and forest ecosystems in Garut District, West Java Province, Indonesia. The rhizophosphate bacteria were isolated and grown in Pikovskaya medium. Bacterial colonies surrounded by clear zone were isolated and subjected to phosphate solubility and phosphatase activity test followed by bioassay. Based on the phosphatase activity, lactic acid production and indole acetic acid (IAA) production were obtained from three isolates of rhizophosphate. The isolates were identified as Bulkholderia vietnamiensis , Enterobacter ludwigii , and Citrobacter amalonaticus the best of which showed high phosphatase content and production of lactic acid, dissolved P and IAA.
Utilization of halotolerant nitrogen biofertilizer can increase N uptake and promote growth and yield of rice plants in saline ecosystem. Halotolerant nitrogen biofertilizer can be applied to seed and seedling in certain dosage. The aim of this study was to obtain the application technique and dosage that can increase N uptake and promote growth and yield of rice plants in saline ecosystem. The research was conducted in the greenhouse in Kawarang District (Indonesia) from September until November 2020. There was used randomized block design which consisted of two factors with three replications. The first factor was application techniques, i.e. seed treatment, nursery treatment, and seed + nursery treatment. The second factor was dosage of halotolerant nitrogen biofertilizer, i.e. 0, 500, 1,000, 1,500 and 2,000 g ha-1. The results showed that halotolerant nitrogen biofertilizer applied in seed and nursery treatment can increase N uptake and plant height by 3.95 g plant-1 and 34.50 cm, respectively. Dosage of 1,500 g ha-1 can increase the total N of soil (0.26%), chlorophyll content (46.97 SPAD), photosynthate accumulation (3.33 g), and rice yield (13.40 t/ha). Application of halotolerant nitrogen biofertilizer in seed and nursery technique at a dosage of 1,500 g ha-1 can be further recommendation in rice cultivation on saline ecosystems.
Salinity intrusion worldwide is a problem of consideration for the global food production and ensuring food security. In this investigation, we focused to find out the key chemical elements for this salinity problem. In this paper, the authors reported the high accumulation of sodium (Na + ) and increased EC (6.9 dS/m) values than that of the previous year (4.67 dS/m). We found the highest EC, Na +, and ESP of 6.9 ds/m, 2.6 meq/100 g of soil, and 19.1%, respectively at Dumki, Potuakhali. The highest increase of exchangeable Na + was found in Tojumuddin, Bhola. The result is 55% more when compared to the previous investigated result. Contrary to the Na + increase, we found an 84-91% decrease of the organic matter (OM) in the investigated samples. The excessive increase of exchangeable Na + and decrease of OM in this investigation indicate the salinity intrusion and low nutrient content in the coastal soils of Bangladesh.
Soils are obviously inconstant and their properties are changing across land use types. Essential soil physico-chemical assets impact the performance of soil and, therefore, information on soil property is important. The objective of the study was to determine effects of different land use systems on soil physico-chemical properties in Wolaita zone, southern Ethiopia. Soil samples were collected from three different land uses, enset ( Ensete ventricosum ), tef ( Eragrostis tef (Zucc.) Trotter) and grass lands. Each replicated three times and the composite sample was taken. All the properties are significantly different and determined using appropriate methods. Soil pH, electrical conductivity, total nitrogen, texture, organic matter and phosphate in soil were determined experimentally to study the effects of land use on them. Changes in soil properties in dissimilar land usage forms at two pits (0–15 and 15–30 cm) were detected on various soil properties signifiant to crop growth. Enset filds had higher pH (5.80), electrical conductivity (EC (0.14 ds/m)), available P (35.25%) and Zn (8.64 mg/kg), exchangeable K (3.12 Cmol(+Kg) which is ascribed due to the input of dung, while tef fields had lowest average K (1.38 cmol (+kg) and Mg (1.89 cmol(+kg), cation exchange capacity (CEC (20.21 cmol(+kg)), total N (0.13%) and OC (1.76%). Most of the physico-chemical properties of the study region were significantly influenced by the different land uses. The evidence derived from the current study will support in mounting maintainable and environmentally constant land use management strategies for the study region. Consequently, supplementary comprehensive studies that include soil characterization and field experiment on crop nutrient requirement should be conducted to test the effect of land use forms on soil physico-chemical properties in terms of sustainable use of the land.
As is well known, tropical peatlands are deposits of terrestrial organic carbon of global importance. It is estimated that around 15% of carbon is stored in peatlands worldwide. Indonesia contains approximately 50% of the world’s tropical peatlands with frequently cited estimates of about 21 Mha. Pelalawan district area (Riau Province) is dominated by peat soils. The land in Pelalawan is mainly covered by industrial plantations of acacia forests and oil palms. The area is very susceptible to the loss of carbon stocks in peat soils due to the opening of drainage channels. This study aims to calculate the carbon stocks of subsurface peatlands in Pelalawan, especially in the research location. The method used is a grid survey, the distance between the particular points is 500 m, which covers the total area of the research site, i.e. 2,500 ha. The number of observation points is 121, which includes measuring the thickness of the peat layer, calculating bulk density, and C organic content. The paper analysed the distribution of carbon stocks in the peat bottom based on the thickness class. The results showed that carbon stocks in the peat bottom in Pelalawan were 218,753.95 tons/ha consisting of 143,138.40 tons/ha in the peat thickness of >300 cm (very deep peatland), 44,999.10 tons/ha in the peat thickness of 200–300 cm (deep peatland), 21,577.67 tons/ha in the peat thickness of 100–200 cm (medium peatland), 4,780.78 tons/ha in the peat thickness of 50–100 (shallow peatland), and 4,258 tons/ha in the peat thickness of 0–50 (very shallow peatland). The research results of this study cover the information on the availability of carbon storage and carbon conservation.
The distribution of black soils in Slovakia can be divided into the two basic groups: distribution of black soils according to the International Network of Black Soils (INBS) and distribution of black soils outside of the INBS specified criteria. Black soils outside of the INBS criteria on selected soil profiles are evaluated in this contribution. Indicators of black soils outside of the INBS criteria are very common in comparison with the first group – existence of mollic horizon – but the depth of mollic horizon is often less than 25 cm where the soil properties are practically the same as in black soils using the INBS criteria (represented by Chernozems and Phaeozems). Other special group of black soils without mollic horizon can be also included in the “black soils” category with low soil reaction (pH/H2O < 5.5 and pH/KCl < 5.0), low base saturation (< 50%) with high content of SOM (10–20%) represented mostly by Andosols and Umbrisols in Slovak conditions. The aim of this paper is to emphasize the significance of black soils outside of the INBS criteria on selected examples of soil profiles in Slovakia. The basic chemical (pH/H2O, pH/KCl, soil organic carbon (SOC), total nitrogen, humic acids, fulvoacids, colour quotient Q46, available nutrients P and K, melanic index) and physical (fractional mechanical composition) procedures were conducted in NPPC – Soil Science and Conservation Research Institute in Bratislava. Based on the obtained results, the black soils outside of the INBS criteria in Slovakia belong mostly to the most fertile soils with the existence of mollic horizon but often shallower than in black soils according to the INBS criteria (< 25 cm) and cultivated mostly as arable land (represented by Chernozems and Phaeozems). Only a smaller part of these soils – without mollic horizon (Andosols, resp. Umbrisols) – belong to the soils with low fertility and are mostly situated in forest protected areas on some volcanic rocks, especially with the occurrence of volcanic glass. Total area of these soils is about 8.7% of soil cover in Slovakia. All the groups of black soils (within and outside of the INBS criteria) have to be strongly protected.
In recent decades, water erosion potential has been recognized as a severe threat against soil sustainability and water resources. The present study was conducted to investigate the relation between geomorphometric parameters and soil type to simulate water erosion in the Emamzadeh watershed located in the northeast of Khuzestan Province. The primary and secondary geomorphic parameters, including slope, plan curvature, profile curvature, flow length, flow accumulation, flow direction, and stream power index (SPI) calculated based on the digital elevation model (DEM). The water erosion measured using available data and laboratory analyzes, then it was predicted with water erosion prediction project (WEPP) model. Our results revealed that the measured soil erosion does not show any relation with geomorphic parameters, while some of the geomorphometric parameters depicted a significant relation with WEPP model’s predictions. A model with an excellent explanation coefficient obtained using multivariate linear regression to predict water erosion. The geomorphometric parameters application allows an estimation of erosion based on simple linear models (R 2 : 0.934, sig: 0.000). Moreover, for SPI, the total curvature was -0.794, plan curvature was -0.658, and profile curvature was 0.746. Therefore, there was a relation between curvature and SPI. Our results showed no specific relation between sediment transport index (STI) and water erosion. The low amount of STI represents the sedimentation areas in the watershed. Generally, application of geomorphometric parameters simplify the soil erosion prediction.
The effect of long-term mineral and organic-mineral fertilization on selected soil properties (pH, total humus and N, available phosphorus, potassium, calcium, magnesium, iron and manganese content) was studied in a stationary trail with tobacco monocropping system. The trial was established on Rendzic Leptosols in 1966. Five treatments were selected for this study, including control without fertilization (Check), nitrogen + phosphorus (NP), nitrogen + potassium (NK), nitrogen + phosphorus + potassium (NPK) and nitrogen + phosphorus + potassium + manure (NPK + manure). Soil samples at a depth of 0–25 cm were collected from all studied plots every year (2014, 2015 and 2016). The results indicated that maintaining humus content at the initial level is not possible through yearly mineral fertilizer application. Long-term mineral phosphorus fertilization increased 5.5–5.7 times available P2O5 in the soil compared to the initial level. The soil available K2O content in NK and NPK treatments increased, respectively, by 41.1% and 44.9% over the initial level. A remarkable increase in available phosphorus (25.5 times) and potassium (2.5 times) content in the soil compared with the initial level was found due to longterm NPK + manure fertilization. The NPK + manure treatment was found to be the most efficient management system in accumulating of total humus and N, available P2O5, K2O, Fe and Mn in a long-term fertilized Rendzic Leposol, under a tobacco monocropping system.
This paper reports the findings of two studies conducted to investigate the effects on pH, Eh and sulfate content of sulfuric soil material of acid sulfate soil following the addition of organic carbon and nitrogen. The first study compared the responses to simple carbon sources (glucose, sodium acetate and molasses) with complex organic matter in the form of chopped Phragmites. The second experiment considered the effect of nitrogen by testing organic matter with varying nitrogen content. The results of the first study showed that the changes in Eh and sulfate contents induced by these treatments mirrored the changes in pH, the highest change being only 5.6 units induced by sodium acetate. These results showed that organic carbon alone was ineffective in treating sulfuric soil material acidity, and that nitrogen was needed. Lucerne hay which had the highest nitrogen content produced the largest increase in pH by 4.2 units, and the changes of pea straw and wheat straw was 3.2 units. It was proposed that the alkalinising effect of the treatments was mediated by anaerobic microbial metabolism which required sources of nitrogen as well as organic carbon. The changes in soil redox conditions by -150 mV measured indicated that sulfur-reducing bacteria induced the changes in Eh, which caused pH to increase and sulfate content to decrease in comparison with nitrate-reducing bacteria. The findings of these studies have implications for management of sulfuric soil material acidity.
Geomorphology depicts the qualitative and quantitative characteristics of both terrain and landscape features combined with the processes responsible for its evolution. Soil erosion by water involves processes, which removes soil particles and organic matter from the upper sheet of the soil surface, and then transports the eroded material to distant location under the action of water. Very few studies have been conducted on the nature and dynamics of soil erosion in the different geomorphologic features. In the present investigation, an attempt has been made to assess the control of geomorphologic features on the soil loss. Universal Soil Loss Equation (USLE) was used to determine soil loss from the various geomorphological landforms. Principal component analysis (PCA) was implemented on the USLE parameters to determine the degree of association between the individual principal components and the USLE-derived soil loss. Results obtained from the investigation signify the influence of the various landforms on soil erosion. PC5 is found to be significantly correlated with the USLE-derived soil loss. The results ascertained significant association between the soil loss and geomorphological landforms, and therefore, suitable strategies can be implemented to alleviate soil loss in the individual landforms.
The article presents the current distribution of arsenic in agricultural soils of Slovakia. The current concentration of arsenic (extracted with aqua regia) was measured and evaluated based on 318 monitoring sites of national soil monitoring system in Slovakia. Based on the obtained results, one can state that the average content of arsenic is lower than the valid hygienic limit for arsenic (25 mg.kg-1) for predominated sandy-loamy and loamy soils in Slovakia. Increased values of arsenic were determined only for the Horná – Upper Nitra region (anthropogenic impact) – 24.5 mg.kg-1 and for the Stredný – Central Spiš region (mixed anthrophogenic and geogenic impact) – 129.5 mg.kg-1. These regions belong to the most arsenic-affected regions in Slovakia, where the content of bioavailable forms of arsenic is also increased in the range of 0.013–0.997 mg.kg-1. The hygienic limit for bioavailable arsenic in soils of Slovakia is 0.4 mg.kg-1. Finally, there is a serious risk of arsenic transport from soil into the plants and food chain especially in case of acid soils. A higher risk of As presence seems to be in anthropogenically affected soils.
Most soil physicochemical parameters do not respond immediately to changes in management when compared to microbiological and biochemical ones; the study of biological and biochemical quality of soils can serve as indicators of their general condition. Enzymatic activities are important in the biochemical functioning of soils. In this work, the activity of three intracellular enzymes of the soil was evaluated: dehydrogenase activity, florescein diacetate hydrolysis and arginine deaminase, its seasonal fluctuation and the effect of two coffee varieties Caturra and Catuai on an agroforestry system. The soil samples were taken during the dry and rainy seasons in two contiguous plots sown with the two coffee varieties and in each one a non-systematic zigzag sampling was carried out. The physical, chemical properties and intracellular enzymatic activities of the soil were determined by the classical methods of analysis and following standard protocols. It was observed that the dehydrogenase activity and hydrolysis of fluorescein diacetate had greater activity in the rainy season regardless of the variety, whereas arginine deaminase showed more activity in the dry season and for the Caturra variety. The intracellular enzymatic activities showed sensitivity to the changes during the sampling period, in soils planted with coffee varieties Caturra and Catuai.
The conventional Boolean logic models of land suitability assessment disregard the continuity concepts of the soil and landscape which might cause inaccurate evaluation and classification. To overcome this uncertainty and consequent constraints, the fuzzy set theories were introduced. Therefore, the current study was undertaken to estimate the optimum soil depth that is used in land suitability evaluation for irrigated rice through the fuzzy sets theory and analytic hierarchy process (fuzzy AHP) in Guilan Province, Iran. The square root and quantitative land suitability evaluation methods were employed to calculate traditional land suitability indices (for depths, 0-25, 0-50, 0-75, and 0-100 cm). Also, fuzzy and fuzzy AHP methods were used to explore new land indices. The Sarma similarity indices were used to compare the results of traditional and fuzzy methods for different soil depths. The results showed that the compatibility percentage between the representative pedons (0-100 cm) and the findings of this research (0-50 and 0-75 cm) were remarkable. Furthermore, the highest compatibility percentage of land suitability class was related to the comparison of these two former depths and 0 to 100 cm depths in each of the two used fuzzy methods. Besides, except for 0-25 cm depths, actual yield revealed a significant and positive correlation with the rest three soil pedon depths. These findings show that considering 0 to 50 cm soil depth might be a relevant alternative as the optimal depth to evaluate land suitability for rice in paddy fields in the Guilan rice-growing area.
In this work, alpha emitters in the twenty soil samples in Al-Mothafeen sites were measured using the CN-85 detectors. The results show that the average values of radon concentration in the air space of the tube and in the sample were 163.15±3.37 Bq/m3 and 5090.54±155.3 Bq/m3, respectively, while the results of annual effective dose were varied from 10.2±0.3 mSv/y to 2.1±0.1 mSv/y with a mean value of 4.1±0.2 mSv/y, radium content were varied from 0.3±0.06 Bq/kg-1 to 0.06±0.02 Bq/kg with a mean value of 0.12±0.03 Bq/kg, and uranium contractions were varied from 9.29±0.33 Bq/kg to 1.90±0.15 Bq/kg with an average of 3.72±0.21 Bq/kg. Also, the average values of mass and surface exhalation rates were 0.95±8.64 mBq/kg.h and 44.59±0.79 mBq/m2.h, respectively. The results were within the normal limits of radiation, according to the International Commission on Radiological Protection (ICRP).
In this paper, there was investigated the content of mercury in soil, plant, water, and hydrobionts in Kyiv and in the Obukhiv district of the Kyiv region. Studied territory is characterized by high anthropogenic load. The solid waste landfill in the Obukhiv district of the Kyiv region was characterized by the highest content of Hg in soil. Hg concentration in Taraxacum officinale L. was the highest among all studied plants, hence the possibility of recommending this species for phytoremediation of mercury-polluted soils. Mercury bioaccumulation of aquatic organisms ( Blicca bjoerkna L., Esox lucius L., Ceratophyllum demersum L.) was much higher than in terrestrial organisms, which indicates the significantly prevailing level of availability and accumulation of mercury for aquatic species in the water environment.
This article discusses a study conducted in order to analyse selected Digital Terrain Model (DTM) derivates in diverse young post-glacial topographic profiles with the aim of identifying terrain features that could be related to the soils that formed there. The area under investigation is within the reach of the youngest Vistulian Glaciation, in the north-east of Poland. The main goal of the study was to reveal indirect relationships between a lithological soil type and terrain forms, which transpire from DTM derivatives. This can directly help to assign the type of soil in the area to one of the three soil types: a) made of sand, b) made of loam, c) wet-soils. The starting point for the research undertaken was the landscape approach to soil modelling and the article deals with medium scales. Derivatives were analysed using vector data notation, focusing on selected derivative values and their spatial location in relation to one another. The results obtained indicate the possibility of using this approach as an auxiliary approach in soil mapping of areas for which the quality of source materials (such as precipitation geometry) is low. Thus, they can be of assistance in improving the existing soil maps of selected scales. The trend revealed in the obtained results of DTM analysis can be considered as a contribution to realisation of assumptions of a study in digital soil mapping with the use of selected methods of AI.
The research was carried out in the morainic areas and in river valleys in NE Poland, where seven sites located in the macroregion of Masurian Lakeland were selected. Thirteen soil profiles representing the following organic soils were studied: earth-covered murshic soils (OMnm), murshic peat soils (OTmu), hemic murshic soils (OMhe) and sapric murshic soils (OMsa). The aim of the research was to investigate the content of selected macro- and microelements in surface formations of organic soils and to determine the influence of sedimentation processes on their spatial distribution. In terms of quantity, the analyzed macro- and microelements can be arranged as follows: Ca > Al > Fe > K > Mg > Na > P > Mn > Zn > Pb > Cr > Ni > Cu > Co. Organic soils situated in the depressions had various degrees of silting with mineral sediments from the nearby areas. Along with erosive waters, deluvial material rich in minerals was flowing along the morainic slopes. Therefore, mineral-organic formations (AO) located in the ecotone zone between mineral and organic soils had the highest content of total Mg – 4.85 g kg-1, K – 5.94 g kg-1, Al – 24.87 g kg-1, Fe – 17.77 g kg-1, Zn – 0.066 g kg-1, Cr – 0.046 g kg-1, Ni – 0.025 g kg-1, Pb – 0.060 g kg-1. The highest content of total calcium, manganese, iron, copper and cobalt was found in mineral-organic formations (AO) and strongly silted murshes (Mtsz). The contents of calcium and sodium were significantly positively and the contents of other macro- and microelements were significantly negatively correlated with the amount of organic matter, organic carbon and total nitrogen.
This study was conducted to evaluate the effects of liquid organic fertilizers (LOFs) and soil moisture status on some biological and physical properties of postharvest soil of maize cultivation. For this purpose, a factorial greenhouse experiment was performed based on the completely randomized design with three replications. Treatments consisted of five levels of LOFs (control, vermicompost tea, vermiwash, plant growth-promoting rhizobacteria [PGPR] enriched vermicompost tea and PGPR enriched vermiwash) and three levels of soil moisture status (field capacity [FC], 0.8 FC and 0.6 FC). The results showed LOFs caused an increase of soil biological properties (soil microbial respiration, soil microbial biomass, dehydrogenase activity and the number of aerobic heterotrophic bacteria) and the improvement of soil physical condition. LOFs increased aggregate stability, hydrophobicity and total porosity, while decreased bulk density and soil penetration resistance. Increasing water stress levels reduced soil biological activity and made soil physical properties more unfavorable. In general, LOFs improved soil conditions by enhancing soil physical and biological properties and decreased the negative effects of water stress. In addition, results showed that LOFs enriched with PGPR could be more effective than non-enriched ones.
Tillage and plant residues influence soil attributes and, consequently, soil quality. Therefore, suitable management and maintaining the stability of soil structure is important. This study was performed to evaluate the effects of tillage systems on soil quality during a 4-year crop rotation (wheat, canola, wheat and tomato) at the Agricultural Research Center of Khorasan Razavi province (Iran) from 2011 to 2015. The study was conducted as a randomized complete block design in a factorial arrangement with 3 replications. For this purpose, conventional tillage (CT), minimum tillage (MT) and no-tillage (NT) systems together with three rates of plant residues (0, 1,500, and 3,000 kg ha-1) were applied annually after harvesting. Soil quality was determined by using the integrated quality index (IQI) and Nemoro quality index (NQI) based on total data set (TDS) and minimum data set (MDS). In total, 23 physical, chemical, and biological soil characteristics were considered as TDS and 7 out of these were selected as MDS for use in the principal component analysis (PCA). Soil quality in different tillage treatments was determined and the most appropriate indices and effective characteristics for soil quality assessment were selected. Correlation coefficients between IQITDS and IQIMDS (r = 0.69) and between NQITDS and NQIMDS (r = 0.76) showed that NQI was a better indicator for assessing soil quality. The NQITDS provided a more accurate and comprehensive assessment of soil quality. However, using MDS reduced the cost and time with proper precision. Soil quality in MT and NT treatments was more desirable than the CT system, and the addition of plant residues improved the soil quality. According to the results of NQITDS, IQITDS, and IQIMDS, soil quality in the NT system with 3,000 kg ha-1 of plant residues and the MT system with 1,500 and 3,000 kg ha-1 of plant residues were more favorable than other soil tillage treatments. Soil characteristics that decreased soil quality in the conventional tillage were soil structure, macro and micronutrients, while in conservation tillage it was micronutrients, especially Zn.
