Soil Total Sulfur Research Articles

Amino acid-sulphur decomposition in agricultural soil profile along a long-term recultivation chronosequence

The significance of sulphur (S) availability for crop yield and quality is highlighted under the global S deficiency scenario. However, little is known about the temporal trend in belowground organic S mineralisation when restoring land to productive agricultural systems, particularly for the deeper soil parts. Therefore, we investigated the decomposition of 35S-labelled methionine in surface (0–30 cm) and subsurface soil (30–60 cm and 60–90 cm) over a 48-year recultivation chronosequence (sampled after1, 8, 14, 24 and 48 years). Soil total sulphur (TS) significantly (p < 0.05) increased in surface soil but not in subsurface soils after 48 years of recultivation. Overall, the immobilisation of 35S-methionine (35S-MB) in subsurface soils relative to year 1 significantly decreased over the chronosequence but did not change in the surface samples. The 35S-MB values in subsurface soils were positively corrected with soil carbon (C) stoichiometry (Pearson correlation, p < 0.05), suggesting the immobilisation of methionine was likely constrained by microbial C demand in deep soil. Compared to year 1, 35S-SO42− released from 35S-methionine significantly declined throughout the older (≥ 8 years) soil profiles. Significant (p < 0.05) changes in the organic 35S partition (35S immobilisation and 35S released as sulphate) were observed in year 8 after the soil was recultivated with N-fixing alfalfa or fertilisers. Whereas, after that (≥ 14 years), soil organic S partition remained affected when conventional tillage and agricultural crops dominated this site. Indicating that the effect of recultivation on organic S decomposition depends on the manner of recultivation management. Our study contributes to an improved understanding of amino acid S and organic S mineralisation under severe anthropogenic disturbance.

Enhancing sulfur absorption in soybean rhizosphere through arbuscular mycorrhizal fungi inoculation: Implications for soil health and crop growth

Soybean, a sulfur-loving cash crop, suffers from declining soil sulfur with continuous cropping, hindering its growth and development. Arbuscular mycorrhizal fungi (AMF) form beneficial partnerships with plant roots, aiding in nutrient uptake and promoting plant growth. Recent research has increasingly focused upon AMF's potential to enhance sulfur absorption through increased rhizosphere microbial activity. This study investigated the impact of AMF inoculation on soil organic sulfur mineralization, microbial community composition, and sulfur cycle function genes in the continuous cropping soybean rhizosphere. 16 S rRNA sequencing and high-throughput qPCR revealed changes in microbial community composition and the expression of sulfur cycle genes. ICP-MS measured total soil sulfur, and the BaSO4 turbidimetric method determined available sulfur. Following inoculation of continuous cropping soybean soil with AMF, it was observed that OTU1851, OTU1897, OTU2148, OTU3303, and OTU3738, five specific rhizospheric soil sulfur cycling microbial communities, were enriched. And AMF inoculation enhanced sulfur cycle function, the abundance of aspA, soxY and yedZ increased by 143.23 %, 236.04 % and 436.64 %. This led to increased soil arylsulfatase (S-ASF) activity (from 39.17 to 49.82 μg/(mL·h)), available sulfur content (from 12.88 to 17.55 mg/kg), and ultimately, improved soybean sulfur absorption and growth. Therefore, this study holds significant implications for improving available sulfur content and utilization in sulfur-deficient soils. Furthermore, it provides a theoretical basis for using AMF as a biofertilizer to remediate sulfur -deficiency, offering a sustainable and environmentally friendly solution.

Depth-wise fractionation of sulphur in cultivated soils of low and mid hills of Himachal Pradesh

The current investigation was conducted to study the fractions of sulphur in nine districts of low and mid hills of Himachal Pradesh. For this purpose 31 representative soil sampling sites were selected from nine districts and the soil samples were analyzed for physicochemical properties and different fractions of sulphur (water soluble sulphur, exchangeable sulphur, available sulphur, non-sulphate sulphur, organic sulphur and total sulphur). The results indicated that the total sulphur in soils varied from 98.2 to 470.1 mg kg-1 in surface soil (0-15 cm) and 67.2 to 370.7 mg kg-1 in sub-surface layer (15-60 cm). The organic sulphur varied from 80.5 to 401.1 mg kg-1 in surface and 44 to 306.1 mg kg-1 in sub-surface layer. The water soluble sulphur, exchangeable sulphur, available sulphur and non-sulphate sulphur varied from 1.7 to 9.2, 2.7 to 18.4, 4.5 to 27.6 and 10.2 to 58.9 mg kg-1 respectively in surface soil and 0.5 to 5.4, 1 to 17.7, 3.7 to 23.5 and 12.5 to 50.2 mg kg-1, respectively in sub-surface soil. It was observed during course of study that with increase in the soil depth the content of different fractions of sulphur decreased. These soils had the major part of their total sulphur content in organic form followed by non-sulphate sulphur, available sulphur, exchangeable sulphur and water soluble sulphur. It can be concluded that the soil texture and organic carbon content played a major role in determining the quantity of different fractions of sulphur in these soils.

Thermodynamics shapes the biogeography of propionate-oxidizing syntrophs in paddy field soils.

Soil biogeochemical processes are not only gauged by the dominant taxa in the microbiome but also depend on the critical functions of its 'rare biosphere' members. Here, we evaluated the biogeographical pattern of 'rare biosphere' propionate-oxidizing syntrophs in 113 paddy soil samples collected across China. The relative abundance, activity and growth potential of propionate-oxidizing syntrophs were analysed to provide a panoramic view of syntroph biogeographical distribution at the continental scale. The relative abundances of four syntroph genera, Syntrophobacter, Pelotomaculum, Smithella and Syntrophomonas were significantly greater at the warm low latitudes than at the cool high latitudes. Correspondingly, propionate degradation was faster in the low latitude soils compared with the high latitude soils. The low rate of propionate degradation in the high latitude soils resulted in a greater increase of the total syntroph relative abundance, probably due to their initial low relative abundances and the longer incubation time for propionate consumption. The mean annual temperature (MAT) is the most important factor shaping the biogeographical pattern of propionate-oxidizing syntrophs, with the next factor being the soil's total sulfur content (TS). We suggest that the effect of MAT is related to the thermodynamic conditions, in which the endergonic constraint of propionate oxidation is leveraged with the increase of MAT. The TS effect is likely due to the ability of some propionate syntrophs to facultatively perform sulfate respiration.

Decay and erosion-related transport of sulfur compounds in soils of rubber based agroforestry

Elemental sulfur is intensively used to control weeds and rubber leaf diseases. However, the mechanisms contributing to elemental sulfur dissipation and decay (hereafter decay) in rubber agroforestry remains unclear. This study relates hydrological processes such as runoff and soil loss to the changes in soil total sulfur (Stot) and sulfate (S–SO4) in typical hillslope rubber agroforestry intercropped with cocoa in Xishuangbanna. The elemental sulfur decay kinetics were studied at two slopes (top and bottom) and three agrosystems (weed, no-weed and mixed). The results show that soil moisture and hydraulic conductivity was uniformly distributed in the experimental rubber agroforestry settings. Higher soil loss and runoff occurred in the bottom slope than the top slope, and in no-weed agrosystem than the herbaceous agrosystems (weed and mixed). The soil loss was mainly driven by runoff. Moreover, Stot and S–SO4 in runoff water were higher in weed agrosystem than no-weed agrosystems. Soil Stot best fit a two-compartments kinetics model, with lower kinetic rates in elemental sulfur applied treatments than in the no-added elemental sulfur treatments, particularly for the weed agrosystem. The soil Stot dissipation time 50% (DT50) was 10–14 times higher in top slope than bottom slope; but 4 and 20 times higher in mixed and no-weed agrosystems, respectively, compared to the weed agrosystem. The soil Stot and S–SO4 contents negatively correlated with soil microbial respiration (CO2 efflux), indicating an adverse influence of elemental sulfur on soil microbial activity. In short, elemental sulfur decay and its S–SO4 transformation depended on soil moisture, runoff, soil erosion and soil CO2, which are in turn affected by slope and agrosystem. This study not only clarifies the mechanisms of elemental sulfur dissipation and decay for its use as an environmental friendly agrochemical; but it also provides information to understand the contribution of runoff and soil loss on these mechanisms in rubber agroforestry.

Spatial and Temporal Variations of Sulfur in Plant-Soil Systems of Phragmites australis and Cyperus malaccensis Marshes in a Typical Subtropical Estuary (Min River), China

To investigate the spatial and temporal variations of sulfur (S) in plant-soil systems of Phragmites australis (PA, native invasive species) and Cyperus malaccensis (CM, common native species) marshes, in situ filed sampling was conducted in the two marshes at different seasons. Results showed that the variations of total sulfur (TS) contents in soils differed among seasons or marshes. Higher levels of TS in soils of PA marsh generally occurred in winter and summer, while those of CM marsh were observed in spring and autumn. Except for winter, the levels of TS in topsoil of CM marsh in other seasons were much higher than those of PA marsh. The variations of TS contents in soils of PA and CM marshes were dependent on the differences in physical and chemical properties (particularly electrical conductivity) of the two marshes and the differences in S absorption and utilization of the two plants. The levels of TS and the accumulation factors of S (AFS) in PA or CM differed within seasons or tissues, which could be interpreted by the differences in growth rhythm and ecological traits between the two plants. The roots/stems (R/S) and roots/leaves (R/L) ratios in PA or CM were mostly than 1, while the stems/leaves (S/L) ratios in both plants were less than 1. Allocations of S in roots of PA were generally higher than those of CM, while the values in aboveground parts of PA were much lower than those of CM. This paper found that the two plants might adopt different strategies for S accumulation and allocation to maintain their competitiveness. The PA might compete primarily by increasing the S accumulation capacities of its roots, whereas the CM might resist the spatial expansion of PA by enhancing the S accumulation capacities of its aboveground tissues.

Impact of long-term application fertilizer on soil total sulphur and valid sulphur

The object of this study was to investigate the effect of the long-term application fertilizer on soil total sulphur and valid sulphur. The results showed that applying fertilizer can improve total sulphur and valid sulphur. In comparison with the low level of nitrogen fertilization treatment, the high one total sulphur and valid sulphur were obviously increased by 29.41% and 19.0%, respectively. Compared with in application of different levels nitrogen and the low level of organic fertilizer, the high level treatment total sulphur and valid sulphur contents were significantly increased by 10.73% and 23.47% than the low one. In application of organic fertilization can also improve total sulphur and valid sulphur The total sulphur and valid sulphur content were higher than organic fertilization only treatment 34.14% and 455.89% in comparison with high levels of organic fertilization mix with nitrogen, phosphorous and potassium fertilization treatment.

Pyrogenic carbon distribution in mineral topsoils of the northeastern United States

Due to its slow turnover rates in soil, pyrogenic carbon (PyC) is considered an important C pool and relevant to climate change processes. Therefore, the amounts of soil PyC were compared to environmental covariates over an area of 327,757km2 in the northeastern United States in order to understand the controls on PyC distribution over large areas. Topsoil (defined as the soil A horizon, after removal of any organic horizons) samples were collected at 165 field sites in a generalised random tessellation stratified design that corresponded to approximately 1 site per 1600km2 and PyC was estimated from diffuse reflectance mid-infrared spectroscopy measurements using a partial least-squares regression analysis in conjunction with a large database of PyC measurements based on a solid-state 13C nuclear magnetic resonance spectroscopy technique. Three spatial models were applied to the data in order to relate critical environmental covariates to the changes in spatial density of PyC over the landscape. Regional mean density estimates of PyC were 11.0gkg−1 (0.84Ggkm−2) for Ordinary Kriging, 25.8gkg−1 (12.2Ggkm−2) for Multivariate Linear Regression, and 26.1gkg−1 (12.4Ggkm−2) for Bayesian Regression Kriging. Akaike Information Criterion (AIC) indicated that the Multivariate Linear Regression model performed best (AIC=842.6; n=165) compared to Ordinary Kriging (AIC=982.4) and Bayesian Regression Kriging (AIC=979.2). Soil PyC concentrations correlated well with total soil sulphur (P<0.001; n=165), plant tissue lignin (P=0.003), and drainage class (P=0.008). This suggests the opportunity of including related environmental parameters in the spatial assessment of PyC in soils. Better estimates of the contribution of PyC to the global carbon cycle will thus also require more accurate assessments of these covariates.

Changes in soil organic matter indices following 32 years of different wheat production management practices in semi-arid South Africa

Soil organic matter (SOM) degradation is common in semi-arid regions due to frequent and intensive cultivation, removal of crop residues after harvesting and warmer environmental conditions. Therefore, we evaluated the effects of long-term wheat production management practices on organic matter content of a Plinthosol in semi-arid South Africa. The treatments included two methods of straw management (unburned and burned), three methods of tillage (no-tillage, stubble mulch and ploughing) and two methods of weeding (chemical and mechanical). Soil samples were collected in 2010 at various depths and analysed for soil organic carbon (SOC), soil total nitrogen (STN) and soil total sulfur (STS) as organic matter indices. Treatments where straw was not burned had greater STN and STS, but lower SOC levels than those where straw was burned. No-tillage had higher SOC levels than the stubble mulch and ploughing treatments only in the 0–50 mm soil layer. Below 100 mm soil depth, higher SOC levels were recorded in the ploughed plots. No-tillage and stubble mulch enhanced STN throughout the soil profile compared to ploughing. Ploughing and stubble mulch treatments had greater STS levels than no-tillage treatments in the upper 250 mm soil layer, and STS in the 0–450 mm soil layer was higher in mechanically weeded plots than in chemically weeded plots. Treatment combinations also showed some significant interactions on these indices, but lack of consistency made it difficult to single out the combination that was superior to others. However, to maintain or improve SOM of this Plinthosol priority should be given to no-tillage and stubble mulch management practices. Wheat grain yields over the 32 years trial period were significantly influenced by straw management and tillage methods, but not by weeding methods.

Sulfur fractions in particle-size separates as influenced by long-term application of mineral and organic fertilizers

A field experiment established in 1962 was chosen to investigate the effect of long-term application of farmyard manure (FYM), compost (COM) and sewage sludge (SS), respectively, in two increments as compared to mineral fertilizer on inorganic and organic S fractions in particle-size separates (&amp;lt; 0.002 mm, 0.002&amp;ndash;0.02 mm, 0.02&amp;ndash;2 mm). Independent of the particle-size the application of the high amounts of COM and SS resulted in the highest total S contents. It is evident that the particle-size fractions &amp;lt; 0.002 mm contained the majority of total soil sulfur (S). The content of plant available S (water-soluble and adsorbed SO&lt;sub&gt;4&lt;/sub&gt;&lt;sup&gt;2&amp;ndash;&lt;/sup&gt;) decreased with increasing particle-size, while the influence of the kind and amount of organic fertilizers was negligible. As compared to C-bonded S sulfate esters were the dominant organic S fraction in size separates. The content of both organic S fractions was highest in the particle-size fraction &amp;lt; 0.002 mm and lowest in the particle-size fraction 0.02&amp;ndash;2 mm. The influence of the application of organic fertilizers was less pronounced. Only high application rates of COM and SS, respectively, resulted in the highest contents of both organic S fractions in the particle-size fractions 0.002&amp;ndash;0.02 mm and 0.02&amp;ndash;2 mm. &amp;nbsp; &amp;nbsp;

A δ34S isoscape of total sulphur in soils across Northern Ireland

Abstract A map of the spatial variation in isotopic composition of a substrate, or isoscape, provides a tool to address a range of research questions, such as the use of isotope fingerprinting to identify the origin of compounds. The focus of this study was to establish a soil S isotope map for Northern Ireland in order to investigate spatial variability within the isotopic composition of total soil sulphur (S). The sample resolution was about one sample every 141 km 2 . δ 34 S values were grouped based on soil type and soil parent material. Total soil S δ 34 S data were grouped according to soil type, to evaluate whether a soil’s characteristics affect its isotopic composition. Gleyed soils had a mean δ 34 S value of +6.3 ± 6.1‰, lower than the means for other soil types. A trend towards higher δ 34 S values (mean δ 34 S of +13.8 ± 6.0‰) was observed in soils with a high organic matter content. No trends in δ 34 S value were observed for other soil types. There were no discernible correlations between total soil S δ 34 S and soil parent material, with the exception of shale and mudstones. The majority of soils derived from shale and mudstones had δ 34 S values at or close to the mean of +4.9‰. A spatially coherent pattern of relatively high soil total S δ 34 S values in the west and north, and low in the SE, is discernible in Northern Ireland. Based on the observed spatial distribution, it has been concluded that the quantity and source (anthropogenic or marine) of wet atmospheric S deposition is a controlling factor on regional variation of soil δ 34 S in Northern Ireland. This S isoscape will assist studies of S cycling in Northern Ireland and may assist in the creation of an ‘isotopic fingerprint’ for a potential ‘input’ source needed to interpret data in traceability studies.

Sulfonate desulfurization in Rhodococcus from wheat rhizosphere communities

Organically bound sulfur makes up about 90% of the total sulfur in soils, with sulfonates often the dominant fraction. Actinobacteria affiliated to the genus Rhodococcus were able to desulfonate arylsulfonates in wheat rhizospheres from the Broadbalk long-term field wheat experiment, which includes plots treated with inorganic fertilizer with and without sulfate, with farmyard manure, and unfertilized plots. Direct isolation of desulfonating rhizobacteria yielded Rhodococcus strains which grew well with a range of sulfonates, and contained the asfAB genes, known to be involved in sulfonate desulfurization by bacteria. Expression of asfA in vitro increased >100-fold during growth of the Rhodococcus isolates with toluenesulfonate as sulfur source, compared with growth with sulfate. By contrast, the closely related Rhodococcus erythropolis and Rhodococcus opacus type strains had no desulfonating activity and did not contain asfA homologues. The overall actinobacterial community structure in wheat rhizospheres was influenced by the sulfur fertilization regime, as shown by specific denaturing gradient gel electrophoresis of PCR amplified 16S rRNA gene fragments, and asfAB clone library analysis identified nine different asfAB genotypes closely affiliated to the Rhodococcus isolates. However, asfAB-based multiplex restriction fragment length polymorphism (RFLP)/terminal-RFLP analysis of wheat rhizosphere communities revealed only slight differences between the fertilization regimes, suggesting that the desulfonating Rhodococcus community does not specifically respond to changes in sulfate supply.

Studies on Nutrient Distribution in Some Zambian Soils with Special Reference to Sulphur Using GIS (Geographic Information Systems) I. Total Sulphur Distribution in Major Zambian Soils

Total sulphur content of some benchmark soils was evaluated by correlating with the contents of soil organic C and amorphous oxides (Al and Fe), and the particle size distribution. An equation model to calculate the content of total soil sulphur was first obtained by regression analysis. Introducing these chemical and physical data of all the map units except for the wetlands into the equation model, the sulphur level on a national scale was estimated for each soil mapping unit in the exploratory soil map of Zambia. Second, the total sulphur content was rated into 3 classes based on the frequency distribution of the total sulphur content in the benchmark soils. Finally, the rated total sulphur content was incorporated into the national soil map database of GIS to produce a map with the total sulphur content of Zambian soils. The extent of each class was calculated and the distribution of the areas was examined in relation to rainfall and soil formation.

A new method for the determination of the 34S/32S ratio of water-soluble sulphur in soil

A new method for the determination of the 34S/32S ratio of water-extractable sulphate in soil is described. Soils are extracted directly with deionized water, which is evaporated down. The remaining residue is then rehydrated and transferred to tin cups containing an adsorbent and mixed with an oxygen donor (V2O5). Samples are then analysed using a continuous flow isotope ratio mass spectrometer. The new method requires around 10 g soil per determination, compared to much larger amounts (up to kilograms) of soil required for the previous methods. Sample preparation and subsequent analysis is quick and efficient. The method is demonstrated using a number of soils collected from around the world to provide a range of determined δ34S values. The δ34S values of water-extractable sulphur were broadly similar to those of the soil total sulphur.

Determination of Total Sulfur in Soils and Plants by an Automated Dry Combustion Method

Determination of total sulfur in environmental samples can be accomplished using automated dry combustion techniques. The analytical performance of an elemental analyzer (CE Instruments) was compared with a method involving dry ashing followed by ion chromatographic detection of sulfate (IC). Samples included certified reference materials, confirmation materials with a known content of sulfur, and several soils and plants. There was a close agreement between both methods. Superior accuracy, precision and detection limits were obtained using the dry combustion method. Current results suggest that the automated dry combustion technique has developed into an adequate method for the determination of the relatively low total sulfur contents commonly encountered in soils and plants.

Influence of Earthworms on the Sulfur Turnover in the Soil

Abstract The effects of earthworm activity on the concentration and isotopic composition of total sulfur in soils was investigated using batch experiments. Two ecologically different lumbricid species, the anecic Lumbricus terrestris and the endogeic Aporrectodea caliginosa, were used. The earthworms were fed birch leaves, beech leaves, cattle manure or mixed plant litter. All food sources differed isotopically (δ(34)S) from the soil (Parabraunerde). As a reference, one experiment was carried out without additional food. The experimental results show, that both earthworm species influence the total S-content and the δ(34)S-values in the soil by digestion of the different food sources. The differences in the total S-content of the earthworm tissues and in the S-isotopic composition of the casts can be attributed to the ecological differences between the earthworm species.

Determination of total sulphur in soil using in‐ductively coupled plasma‐atomic emission spectrometry

Abstract Total sulphur in soils was determined by ignition with a NaHCO3/Ag2O mixture, extraction with HC1 and measurement of sulphur by inductively coupled plasma‐atomic emission spectrometry. Significant spectral interference from other extracted elements (mainly iron and aluminium) was corrected using an off‐peak background reading. Recovery of sulphur added to soil as K2SO4 was complete and barium did not interfere when added in amounts equivalent to 2000 μg g‐1 soil. The total sulphur values for a range of New Zealand pastoral soils determined by this method were on average 104% (SEM=1,4) of the values obtained by the NaOBr oxidation method of Tabatabai & Bremner (1). The method enables analysis of relatively large sample numbers.

Determination of total sulfur in soil and plant samples using sodium bicarbonate/silver oxide, dry ashing and ion chromatography

Abstract The determination of total sulfur (S) in soils and plant tissue samples can be accomplished using a combination of sodium bicarbonate/silver oxide, dry ashing and ion chromatography(IC). The proposed method offers high precision and acceptable accuracy for samples with more than 0.02% S. At the same time this procedure makes use of standard analytical equipment used in other phases of soil, water and plant tissue analysis. Soil sample sizes larger than 0.1g or high total S or barite (BaSO4) may not have acceptable S recoveries due to incomplete S oxidation or dissolution of BaSO4. In order to optimize recoveries of total S in these special soil samples, varying (decreasing) sample sizes is required.

Determination of total sulfur in soils and plant materials by ion chromatography

Abstract An accurate and precise ion Chromatographie (IC) method is described for determination of total S in soils and plant materials. It involves ignition of a mixture of soil and NaHCO3or plant material and NaHCO3containing Ag2O at 550°C for 3 h. The residue is dissolved in 1MHOAc, diluted with deionized water, filtered, and analyzed for S02‐ 4by a Dionex model 2002i ion Chromatograph. Results by the IC method of seven Iowa soils, three Chilean soils, and 10 plant materials agreed closely with those obtained by the methylene blue method after alkaline oxidation with NaOBr. In general, the IC method was more precise than the methylene blue method. The method is simple and requires a minimum of analytical skill. A single operator can analyze 30–40 soil or plant samples in a normal working day.

Determination of chloride, nitrate, sulphate and total sulphur in environmental samples by single-column ion chromatography

The analytical performance characteristics of a single-column ion chromatography system are reported. The data were obtained by using conductivity detection as well as by an indirect ultraviolet technique. The method has been applied to the determination of Cl −, NO 3 − and SO 4 2− in samples of rain, sewer water, and soil-pore water. Also described are two methods which allow ion Chromatographic analysis of CaS0 4-extractable nitrate in soils, and total sulphur in soils, marine sediments and plant tissue.