Organic matter in black sand soils related to alkyl carbon and organo-mineral structures at the microscale

2021 ◽  
Author(s):  
Steffen A. Schweizer ◽  
Emanuele Lugato ◽  
Carmen Höschen ◽  
Ingrid Kögel-Knabner
Keyword(s):  
Organic Matter ◽  
Western Europe ◽  
Secondary Ion Mass Spectrometry ◽  
C:N Ratio ◽  
Fine Fraction ◽  
Soil Mass ◽  
Mineral Particle ◽  
Black Sand ◽  
Soil Database ◽  
Statistical Survey

<p><span>Agricultural sandy soils with high organic matter (OM) contents are generally unexpected under the current paradigm of organic matter formation and stabilization. These so-called black sand soils occur in North-Western Europe and have been related to historical heathland vegetation. The properties and mechanisms of the high OM sequestration in these soils are not clear as they exceed common observations of OM stored in coarse-textured soils. In this study, we analyzed a subset of samples with ‘black sand’ properties from the European soil database “Land Use/Cover Area frame statistical Survey” (LUCAS). Through particle size fractionation, we isolated the fine fraction <20 µm which contained, on average, 55 % of the total soil organic carbon (OC), in only 8 % of the corresponding soil mass. The fine fraction <20 µm contained 301 mg OC g<sup>-1</sup> with a C:N ratio of 17.4 on average and was positively correlated with the bulk soil OC. The characterization of OM composition in the fine fractions by solid-state <sup>13</sup>C nuclear magnetic resonance (NMR) spectroscopy revealed that the share of alkyl C increased with OC concentrations whereas O/N-alkyl C decreased. To analyze the distribution of OM at the microscale, we analyzed five samples from the <20 µm fraction containing a gradient of 245-378 mg OC g<sup>‑1</sup> with nanoscale secondary ion mass spectrometry (NanoSIMS) at a spatial resolution of 120 nm. These microscale measurements revealed fine mineral particle structures associated with heterogeneously distributed OM. Using image analysis, we found that the proportion of OM-dominated area (indicated by <sup>12</sup>C<sub>2</sub><sup>-</sup> and <sup>26</sup>CN<sup>-</sup>) increased from 52 to 80 % on average with increasing OC concentration of the fine fractions. A majority of OM-dominated area was correlated with higher <sup>42</sup>AlO<sup>-</sup> counts, which might suggest a preferential co-localization. In turn, the particle area which was dominated by minerals (indicated by <sup>16</sup>O<sup>‑</sup>, <sup>28</sup>Si<sup>‑</sup>, <sup>42</sup>AlO<sup>‑</sup> and <sup>72</sup>FeO<sup>‑</sup>) contained less Al and more Si. This shows that the more alkylated and OM-rich fine fractions are related with distinct patterns of organo-mineral structures at the microscale.</span></p>

scholarly journals Influence of Physicochemical Characteristics of Bean Crop Soil in Trichoderma spp. Development

Agronomy ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 274
Author(s):  
Sara Mayo-Prieto ◽  
Alejandra J. Porteous-Álvarez ◽  
Sergio Mezquita-García ◽  
Álvaro Rodríguez-González ◽  
Guzmán Carro-Huerga ◽  
...  
Keyword(s):  
Organic Matter ◽  
Sandy Loam ◽  
C:N Ratio ◽  
Physicochemical Characteristics ◽  
Soil Parameters ◽  
Physical Parameters ◽  
Silt Loam ◽  
Chemical Methods ◽  
Trichoderma Spp ◽  
Trichoderma Species

Spain has ranked 6th on the harvested bean area and 8th in bean production in the European Union (EU). The soils of this area have mixed silt loam and sandy loam texture, with moderate clay content, neutral or acidic pH, rich in organic matter and low carbonate levels, providing beans with high water absorption capacity and better organoleptic qualities after cooking. Similar to other crops, it is attacked by some phytopathogens. Hitherto, chemical methods have been used to control these organisms. However, with the Reform of the Community Agrarian Policy in the EU, the number of authorized plant protection products has been reduced to prevail food security, as well as to be sustainable in the long term, giving priority to the non-chemical methods that use biological agents, such as Trichoderma. This study aimed to investigate the relative importance of various crop soil parameters in the adaptation of Trichoderma spp. autoclaved soils (AS) and natural soils (NS) from the Protected Geographical Indication (PGI) “Alubia La Bañeza—León” that were inoculated with Trichoderma velutinum T029 and T. harzianum T059 and incubated in a culture chamber at 25 °C for 15 days. Their development was determined by quantitative PCR. Twelve soil samples were selected and analyzed from the productive zones of Astorga, La Bañeza, La Cabrera, Esla-Campos and Páramo. Their physicochemical characteristics were different by zone, as the texture of soils ranged between sandy loam and silt loam and the pH between strongly acid and slightly alkaline, as well as the organic matter (OM) concentration between low and remarkably high. Total C and N concentrations and their ratio were between medium and high in most of the soils and the rest of the micronutrients had an acceptable concentration except for Paramo’s soil. Both Trichoderma species developed better in AS than in NS, T. velutinum T029 grew better with high levels of OM, total C, ratio C:N, P, K, Fe, and Zn than T. harzianum T059 in clay soils, with the highest values of cation exchange capacity (CEC), pH, Ca, Mg and Mn. These effects were validated by Canonical Correlation Analysis (CCA), texture, particularly clay concentration, OM, electrical conductivity (EC), and pH (physical parameters) and B and Cu (soil elements) are the main factors explaining the influence in the Trichoderma development. OM, EC, C:N ratio and Cu are the main soil characteristics that influence in T. velutinum T029 development and pH in the development of T. harzianum T059.

scholarly journals Impact of soil use on aggregate stability and its relationship with soil organic carbon at two different altitudes in the Colombian Andes

2019 ◽  
Vol 37 (3) ◽  
pp. 263-273
Author(s):  
Efraín Francisco Visconti-Moreno ◽  
Ibonne Geaneth Valenzuela-Balcázar
Keyword(s):  
Organic Matter ◽  
Organic Carbon ◽  
Soil Organic Carbon ◽  
Aggregate Stability ◽  
Tropical Climate ◽  
Mineral Particle ◽  
Organic Carbon Content ◽  
Rice Soils ◽  
Organic Matter Pool ◽  
Different Altitudes

The stability of soil aggregates depends on the organic matter, and the soil use and management can affect the soil organicmatter (SOM) content. Therefore, it is necessary to know therelationship between aggregate stability and the content of SOMin different types of soil use at two different altitudes of theColombian Andes. This study examined the conditions of soilaggregate stability expressed as a distribution of the size classes of stable aggregates (SA) and of the mean weighted diameter of the stable aggregates (MWD). To correlate these characteristics with the soil organic carbon (OC), we measured the particulate organic matter pool (POC), the OC associated with the mineral organic matter pool (HOC), the total organic carbon content (TOC), and the humification rate (HR). Soils were sampled at two altitudes: 1) Humic Dystrudepts in a cold tropical climate (CC) with three plots: tropical mountain rainforest, pastures, and crops; 2) Fluvaquentic Dystrudepts in a warm tropical climate (WC) with three plots: tropical rainforest, an association of oil palm and pastures, and irrigated rice. Soils were sampled at three depths: 0-5, 5-10 and 10-20 cm. The physical properties, mineral particle size distribution, and bulk density were measured. The content of SA with size>2.36 mm was higher in the CC soil (51.48%) than in the WC soil (9.23%). The SA with size 1.18-2.36 mm was also higher in the CC soil (7.78%) than in the WC soil (0.62%). The SA with size 0.60-1.18 mm resulted indifferent. The SA with size between 0.30 and 0.60 mm were higher in the WC soil (13.95%) than in the CC soil (4.67%). The SA<0.30 mm was higher in the WC soil (72.56%) than in the CC soil (32.15%). It was observed that MWD and the SA>2.36 mm increased linearly with a higher POC, but decreased linearly with a higher HR. For the SA<0.30 mm, a linear decrease was observed at a higher POC, while it increased at a higher HR.

scholarly journals Soil carbon and nitrogen erosion in forested catchments: implications for erosion-induced terrestrial carbon sequestration

2015 ◽  
Vol 12 (16) ◽  
pp. 4861-4874 ◽  
Author(s):  
E. M. Stacy ◽  
S. C. Hart ◽  
C. T. Hunsaker ◽  
D. W. Johnson ◽  
A. A. Berhe
Keyword(s):  
Organic Matter ◽  
Sierra Nevada ◽  
Sediment Yield ◽  
Forest Ecosystems ◽  
Mineral Particle ◽  
Strongly Correlated ◽  
Terrestrial Carbon ◽  
Stream Discharge ◽  
C And N ◽  
Sediment Export

Abstract. Lateral movement of organic matter (OM) due to erosion is now considered an important flux term in terrestrial carbon (C) and nitrogen (N) budgets, yet most published studies on the role of erosion focus on agricultural or grassland ecosystems. To date, little information is available on the rate and nature of OM eroded from forest ecosystems. We present annual sediment composition and yield, for water years 2005–2011, from eight catchments in the southern part of the Sierra Nevada, California. Sediment was compared to soil at three different landform positions from the source slopes to determine if there is selective transport of organic matter or different mineral particle size classes. Sediment export varied from 0.4 to 177 kg ha−1, while export of C in sediment was between 0.025 and 4.2 kg C ha−1 and export of N in sediment was between 0.001 and 0.04 kg N ha−1. Sediment yield and composition showed high interannual variation. In our study catchments, erosion laterally mobilized OM-rich litter material and topsoil, some of which enters streams owing to the catchment topography where steep slopes border stream channels. Annual lateral sediment export was positively and strongly correlated with stream discharge, while C and N concentrations were both negatively correlated with stream discharge; hence, C : N ratios were not strongly correlated to sediment yield. Our results suggest that stream discharge, more than sediment source, is a primary factor controlling the magnitude of C and N export from upland forest catchments. The OM-rich nature of eroded sediment raises important questions about the fate of the eroded OM. If a large fraction of the soil organic matter (SOM) eroded from forest ecosystems is lost during transport or after deposition, the contribution of forest ecosystems to the erosion-induced C sink is likely to be small (compared to croplands and grasslands).

Soil organic carbon and nitrogen sequestration and turnover in aggregates under subtropical leucaena–grass pastures

Soil Research ◽  
2018 ◽  
Vol 56 (6) ◽  
pp. 632 ◽  
Author(s):  
Kathryn Conrad ◽  
Ram C. Dalal ◽  
Ryosuke Fujinuma ◽  
Neal W. Menzies
Keyword(s):  
Organic Matter ◽  
Organic Carbon ◽  
Soil Organic Carbon ◽  
Soil Aggregates ◽  
Soil Mass ◽  
Δ13c And Δ15n ◽  
Organic C ◽  
Carbon And Nitrogen ◽  
Nitrogen Sequestration ◽  
C And N

Stabilisation and protection of soil organic carbon (SOC) in macroaggregates and microaggregates represents an important mechanism for the sequestration of SOC. Legume-based grass pastures have the potential to contribute to aggregate formation and stabilisation, thereby leading to SOC sequestration. However, there is limited research on the C and N dynamics of soil organic matter (SOM) fractions in deep-rooted legume leucaena (Leucaena leucocephala)–grass pastures. We assessed the potential of leucaena to sequester carbon (C) and nitrogen (N) in soil aggregates by estimating the origin, quantity and distribution in the soil profile. We utilised a chronosequence (0–40 years) of seasonally grazed leucaena stands (3–6 m rows), which were sampled to a depth of 0.3 m at 0.1-m intervals. The soil was wet-sieved for different aggregate sizes (large macroaggregates, >2000 µm; small macroaggregates, 250–2000 µm; microaggregates, 53–250 µm; and <53 µm), including occluded particulate organic matter (oPOM) within macroaggregates (>250 µm), and then analysed for organic C, N and δ13C and δ15N. Leucaena promoted aggregation, which increased with the age of the leucaena stands, and in particular the formation of large macroaggregates compared with grass in the upper 0.2 m. Macroaggregates contained a greater SOC stock than microaggregates, principally as a function of the soil mass distribution. The oPOM-C and -N concentrations were highest in macroaggregates at all depths. The acid nonhydrolysable C and N distribution (recalcitrant SOM) provided no clear distinction in stabilisation of SOM between pastures. Leucaena- and possibly other legume-based grass pastures have potential to sequester SOC through stabilisation and protection of oPOM within macroaggregates in soil.

scholarly journals The effect of sub-irrigation with untreated and treated municipal wastewater on organic matter and Nitrogen content on two soil types

2019 ◽  
Keyword(s):  
Organic Matter ◽  
Nitrogen Content ◽  
Total Nitrogen ◽  
Municipal Wastewater ◽  
Tap Water ◽  
Soil Mass ◽  
Treated Wastewater ◽  
Total N ◽  
Untreated Wastewater ◽  
Zone Ii

<p>In order to study the chemical parameters of the soil after sub-irrigation with wastewater, a system was installed in one of the greenhouses of the Agricultural University of Athens. Wastewater was applied subsurface into the soil mass of the pots were used. Three treatments were used: Untreated wastewater (U), Treated wastewater (T) and tap water (W) as control. Two different types were used: Soil (a) characterized as Sandy loam and soil (b) characterized as Loamy sand. Moreover, in order to investigate the change of total Nitrogen and organic matter concentrations at the point where the emitter was placed, the soil mass was divided into two zones. The upper (zone I) and the lower one (zone II). The total nitrogen content, ammonia nitrogen (NH4-N), nitrogen nitrate (NO3-N) and the percentage of organic matter, were determined in the soil samples. Statistically significant differences (p &lt;0, 05) were observed in the organic matter and the total N%, only for soil (b). For soil (a), organic matter percentage was increased in zone (I) (irrigation with treated wastewater at 20 cm depth). For soil (b), total N% was increased in zone (I), while nitrate and ammonium were increased in zone (II) (irrigation with untreated wastewater at 20 cm depth).</p>

scholarly journals Strong warming of subarctic forest soil deteriorated soil structure via carbon loss – Indications from organic matter fractionation

2019 ◽  
Author(s):  
Christopher Poeplau ◽  
Páll Sigurðsson ◽  
Bjarni D. Sigurðsson
Keyword(s):  
Organic Matter ◽  
Forest Soil ◽  
Soil Structure ◽  
Terrestrial Ecosystems ◽  
Soil Mass ◽  
Soil Warming ◽  
Ecosystem Responses ◽  
Structure Changes ◽  
Northern Latitudes ◽  
Fraction Distribution

Abstract. Net loss of soil organic carbon (SOC) from terrestrial ecosystems is a likely consequence of global warming and this may affect key soil functions. Strongest changes in temperature are expected to occur at high northern latitudes, with boreal forest and tundra as prevailing land-cover types. However, specific ecosystem responses to warming are understudied. We used a natural geothermal soil warming gradient in an Icelandic spruce forest (0–17.5 °C warming intensity) to assess changes in SOC content in 0–10 cm (topsoil) and 20–30 cm (subsoil) after 10 years of soil warming. Five different SOC fractions were isolated and the amount of stable aggregates (63–2000 µm) was assessed to link SOC to soil structure changes. Results were compared to an adjacent, previously investigated warmed grassland. Soil warming had depleted SOC in the forest soil by −2.7 g kg−1 °C−1 (−3.6 % °C−1) in the topsoil and −1.6 g kg−1 °C−1 (−4.5 % °C−1) in the subsoil. Distribution of SOC in different fractions was significantly altered, with particulate organic matter and SOC in sand and stable aggregates being relatively depleted and SOC attached to silt and clay being relatively enriched in warmed soils. The major reason for this shift was aggregate break-down: topsoil aggregate mass proportion was reduced from 60.7 ± 2.2 % in the unwarmed reference to 28.9 ± 4.6 % in the most warmed soil. Across both depths, loss of one unit SOC caused a depletion of 4.5 units aggregated soil, which strongly affected bulk density (R2 = 0.91 when correlated to SOC and R2 = 0.51 when correlated to soil mass in stable aggregates). The proportion of water extractable carbon increased with decreasing aggregation, indicating an indirect SOC protective effect of aggregates > 63 µm. Topsoil changes in total SOC and fraction distribution were more pronounced in the forest than in the adjacent warmed grassland soils, due to higher and more labile initial SOC. However, no ecosystem effect was observed in the response of subsoil SOC and fraction distribution. Whole profile differences across ecosystems might thus be small. Changes in soil structure upon warming should be studied more deeply and taken into consideration when interpreting or modelling biotic responses to warming.

Estimating soilpCO2using paleosol carbonates: implications for the relationship between primary productivity and faunal richness in ancient terrestrial ecosystems

Paleobiology ◽  
2012 ◽  
Vol 38 (4) ◽  
pp. 585-604 ◽  
Author(s):  
Timothy S. Myers ◽  
Neil J. Tabor ◽  
Louis L. Jacobs ◽  
Octávio Mateus
Keyword(s):  
Organic Matter ◽  
Primary Productivity ◽  
Western Europe ◽  
Central Africa ◽  
Terrestrial Ecosystems ◽  
Upper Jurassic ◽  
Morrison Formation ◽  
Positive Correlation ◽  
Terrestrial Environments ◽  
Ancient Ecosystems

In this paper we present a method for estimating soilpCO2in ancient environments using the measured carbon-isotope values of pedogenic carbonates and plant-derived organic matter. The validity of soilpCO2estimates proves to be highly dependent on the organic δ13C values used in the calculations. Organic matter should be sourced from the same paleosol profiles as sampled carbonates to yield the most reliable estimates of soilpCO2. In order to demonstrate the potential use of soilpCO2estimates in paleoecological and paleoenvironmental studies, we compare samples from three Upper Jurassic localities. SoilpCO2estimates, interpreted as a qualitative indicator of primary paleoproductivity, are used to rank the Late Jurassic terrestrial environments represented by the Morrison Formation in western North America, the informally named Lourinhã formation in Western Europe, and the Stanleyville Group in Central Africa. Because modern terrestrial environments show a positive correlation between primary productivity and faunal richness, a similar relationship is expected in ancient ecosystems. When the relative paleoproductivity levels inferred for each study area are compared with estimates of dinosaur generic richness, a positive correlation emerges. Both the Morrison and Lourinhã formations have high inferred productivity levels and high estimated faunal richness. In contrast, the Stanleyville Group appears to have had low primary productivity and low faunal richness. Paleoclimatic data available for each study area indicate that both productivity and faunal richness are positively linked to water availability, as observed in modern terrestrial ecosystems.

scholarly journals Distribution of Taraxacum microspecies along soil property gradients in salt and brackish meadows on the Polish Baltic coast

2019 ◽  
Vol 78 (1) ◽  
pp. 35-45 ◽  
Author(s):  
Beata Bosiacka ◽  
Helena Więcław ◽  
Paweł Marciniuk ◽  
Marek Podlasiński
Keyword(s):  
Organic Matter ◽  
Soil Fertility ◽  
Soil Property ◽  
C:N Ratio ◽  
Organic Matter Content ◽  
Matter Content ◽  
Soil Parameters ◽  
Vegetation Patterns ◽  
Baltic Coast ◽  
Coastal Meadows

Abstract The vegetation of protected salt meadows along the Baltic coast is fairly well known; however, dandelions have been so far treated as a collective species. The aim of our study was to examine the microspecies diversity of the genus Taraxacum in Polish salt and brackish coastal meadows and to analyse soil property preferences of the dandelion microspecies identified. In addition, we analysed the relations between soil properties and vegetation patterns in dandelion-supporting coastal meadows (by canonical correspondence analysis). The salt and brackish meadows along the Polish Baltic coast we visited were found to support a total of 27 dandelion microspecies representing 5 sections. Analysis of vegetation patterns showed all the soil parameters (C:N ratio, organic matter content, pH, concentration of Mg, P, K, electrolytic conductivity of the saturated soil extract ECe) to explain 32.07% of the total variance in the species data. The maximum abundance of most dandelion microspecies was associated with the highest soil fertility, moderate pH values and organic matter content, and with the lowest magnesium content and soil salinity. The exceptions were T. latissimum, T. stenoglossum, T. pulchrifolium and T. lucidum the occur-rence of which was related to the lowest soil fertility and the highest salinity. In addition, several microspecies (T. leptodon, T. gentile, T. haematicum, T. fusciflorum and T. balticum) were observed at moderate C:N ratios and ECe. Four other microspecies (T. infestum, T. cordatum, T. hamatum, T. sertatum) occurred at the lowest pH and organic matter content. The information obtained increases the still insufficient body of knowledge on ecological spectra of individual dandelion microspecies, hence their potential indicator properties.

Sign in / Sign up

Export Citation Format

Share Document