Peat Research Articles

Composition and Distribution of Organic Compounds in Oil-Contaminated Peat Soils of the Mamontovskoye Field (KhMAO–Yugra)

Composition and Distribution of Organic Compounds in Oil-Contaminated Peat Soils of the Mamontovskoye Field (KhMAO–Yugra)

Karakteristik Kimia Tanah Gambut pada Tiga Tipe Penggunaan Lahan

Peat soil is a soil that has been decomposed by organic matter. Man-made peatlands have been converted into agricultural land. In addition to being turned into agricultural land, some peatlands are also not used, causing the land to turn into shrubs and causing land to burn because it is not managed by the owner. Peatlands therefore consist of various types of land use. Peat soils in different types of land use have different characteristics. The purpose of the study was to determine the differences in some of the chemical properties of peatlands that have been used for shrubs, open land, and agriculture. To see the differences in soil chemical properties on various land uses, descriptive analysis, and standard deviation are used by presenting bar charts. The soil pH content on agricultural land is higher. The C-organic content in shrubs is higher than in agricultural land. Ash content on agricultural land is higher. Dissolved organic carbon on agricultural land tends to be lower.

Peat Ground Improvement with GeoPolySoilS

Peat soil is frequently seen as a soil foundation concern which normally required soil stabilization work. This study is conducted to assess the strength of peat soil mixed with GeoPolySoilS as a proposed ground improvement work for peat soil in Kampung Johan Setia in Klang Selangor, Malaysia. In order to look into the strength improvement of this peat soil, laboratory tests were conducted namely Unconfined Compressive Strength Test (UCT) and Calfornia Bearing Ratio Test (CBR). The highest strength of UCT for the uncured soils with 14% GeoPolySoilS is 161 kPa whilst for the sample that was cured for 7,14,28 and 50 days, the highest value of UCT with 20% GeoPolySoilS are 58.08 kPa,61.66 kPa, 95.62 kPa and 80.04 kPa respectively. For the CBR value, the highest top layer value is 8.12% for peat soil mixed with 14% GeoPolySoilS whilst the highest value for the bottom layer is 62.25% for unsoaked CBR. For soaked CBR, the highest top layer value is 5.82% for 20% GeoPolySoilS and the highest value for bottom layer is 43.07%. The strength of the modified peat increased with the increased of curing time and the percentage of GeoPolySoilS.

Deciphering the corrosion puzzle: Nano-iron-biochar composite – Not a quick fix for metal immobilization in peat soils

The use of zero-valent iron nanoparticles in the remediation of metal-contaminated soils has received considerable attention. Upon introduction into the soil, zero-valent iron particles corrode into iron oxides, known for their high adsorption capacity for potentially toxic metals. While limited research has directly compared zero-valent iron micro- and nanoparticles, it is important to investigate whether particle size contributes to effective soil remediation. This study focuses on elucidating the comparative kinetics of iron corrosion using iron powder and a nano-iron-biochar composite. In a model experiment, these materials were exposed to a cellulose/biochar mixture and peat for five months. Mössbauer spectroscopy, X-ray diffraction, scanning electron microscopy with energy dispersive X-ray spectroscopy, and transmission electron microscopy with electron diffraction were used to analyze the corrosion products. The results show a slow corrosion rate in the nano-iron-biochar composite in cellulose due to the protective effect of biochar on the embedded iron nanoparticles. In addition, iron corrosion in peat was inhibited, likely due to the presence of humic substances. Transmission electron microscopy after five months of corrosion revealed round metal particles encased in a graphite capsule with visible channels. Large dissolved organic matter molecules in the peat likely block these channels, inhibiting metallic iron corrosion. Consequently, the nano-iron-biochar composite emerges as a slow-reacting option for immobilizing soil metals in peat. This study highlights the need for further research involving long-term field experiments.

The Characterization of Biodiversity and Soil Emission Activity of the “Ladoga” Carbon-Monitoring Site

The global climate crisis forces mankind to develop carbon storage technologies. “Ladoga” carbon monitoring site is part of the Russian climate project “Carbon Supersites”, which aims to develop methods and technologies to control the balance of greenhouse gases in various ecosystems. This article shows the condition of soil and vegetation cover of the carbon polygon “Ladoga” using the example of a typical southern taiga ecosystem in the Leningrad region (Russia). It is revealed that soils here are significantly disturbed as a result of agrogenic impact, and the vegetation cover changes under the influence of anthropogenic activity. It has been found that a considerable amount of carbon is deposited in the soils of the carbon polygon; its significant part is accumulated in peat soils (60.0 ± 19.8 kg × m−2 for 0–100 cm layer). In agrogenically disturbed and pristine soils, carbon stocks are equal to 12.8 ± 2.9 kg × m−2 and 8.3 ± 1.3 kg × m−2 in the 0–100 cm layer, respectively. Stocks of potentially mineralizable organic matter (0–10 cm) in peat soils are 0.48 ± 0.01 kg × m−2; in pristine soils, it is 0.58 ± 0.06 kg × m−2. Peat soils are characterized by a higher intensity of carbon mineralization 9.2 ± 0.1 mg × 100 g−1 × day−1 with greater stability. Carbon in pristine soils is mineralized with a lower rate—2.5 ± 0.2 mg × 100 g−1 × day−1. The study of microbial diversity of soils revealed that the dominant phyla of microorganisms are Actinobacteria, Bacteroidetes, and Proteobacteria; however, methane-producing Archaea—Euryarchaeota—were found in peat soils, indicating their potentially greater emission activity. The results of this work will be useful for decision makers and can be used as a reference for estimating the carbon balance of the Leningrad region and southern taiga boreal ecosystems of the Karelian Isthmus.

DNA-based occurrence dataset on peatland fungal communities studied by metabarcoding in north-western Siberia.

The paper represents the first DNA-based occurrence dataset on peatland fungal communities published for north-western Siberia, the first for Russia and complements several existing datasets on metabarcoding of peat soils globally. The aim of the present publication is to describe the first DNA-based occurrence dataset on fungal communities in peat soils and other substrates studied by the eDNA approach in the Mukhrino raised bog, located in a large paludified area of north-western Siberia. A comparison of the species diversity of larger fungi identified by the conventional approach and by eDNA showed a high proportion of shared taxa. Other groups (mainly Ascomycota), described by metabarcoding, revealed high diversity compared with conventional observation. Overall, the species richness identified in one peatland locality (the Mukhrino Bog) was comparable in number of species to the global estimation of fungal diversity in peatlands, previously reported in literature.

Thermal Decomposition and Combustion Analysis of Malaysian Peat Soil Samples Using Coats Redfern Model-free Method

This research investigates the thermal decomposition behaviour of Malaysian peat soil through thermogravimetric analysis at varying heating rates. The study aims to analyse the thermal kinetics of decomposition for distinct peat soil types under inert and oxidative atmospheres while considering the role of available oxygen. The investigation encompasses virgin and agricultural peat, employing a non-isothermal thermogravimetric analysis technique to evaluate thermal decomposition characteristics and compute kinetic parameters using the Coats Redfern model-free approach. The pyrolysis profiles reveal three primary stages: moisture evaporation (30–180°C), organic component decomposition (200–500°C), and mineral decomposition (600–800°C). Virgin peat experiences a 43% mass loss during pyrolysis, while agricultural peat shows a 46% mass loss, emphasising insights into thermal behaviour and consistent decomposition patterns across peat types. Combustion profiles exhibit three main stages: dehydration (30–180°C), oxidative pyrolysis transforming organic matter into volatiles and char (200–300°C), and subsequent char oxidation (300–500°C). The study determines average activation energy trends, measuring 14.87 kJ/mol for virgin peat and 5.37 kJ/mol for agricultural peat under an inert atmosphere, and 28.89 kJ/mol for virgin peat and 36.66 kJ/mol for agricultural peat under an oxidative atmosphere. The research introduces an innovative two-step reaction model elucidating peat thermal decomposition kinetics (excluding dehydration), including a discussion on the impact of oxygen availability on kinetic parameters. These findings essential peat fire smouldering modelling, contributing to peat combustion behaviour for effective strategies to reduce peat fire risks.

Effects of Land Fires on Peat Soil Characteristics in Landasan Ulin District, Banjarbaru City

Peat is a type of soil that has a dry condition, which causes it to burn easily. When the peat is burned, the spread of fire will occur very quickly until it reaches the ground, because peat soil does not contain solid soil, but branches, grass, and tree debris. Even though the fire on the surface has been extinguished, the fire that is in the inner layer is not necessarily extinguished. This study aims to determine the effect of land fires on the characteristics of peat soil in Landasan Ulin District, Banjarbaru City, including the physical and chemical properties of the peat soil. This research uses quantitative methods with a descriptive approach. Primary data in this study include: texture, color, bulk density (BD), soil structure, pH, and nutrients. Primary data collection was in the form of field surveys by looking at peatlands and the physical and chemical characteristics of the soil with 14 samples taken at 7 sample points. The results showed that on peatlands that had been burned, there was an increase in the value of BD, pH, and soluble Fe so that the potential for absorbing and distributing water was low, and plant roots were difficult to absorb nutrients. Organic C content also decreased, causing soil fertility to decrease.

Pengaruh Tinggi Muka Air Tanah Gambut terhadap Evolusi Gas CO2

This study aims to determine the effect of the groundwater level on the evolution of CO2 in peat soils if the groundwater table is lowered from a depth of 40 cm (PP No. 57 of 2016 concerning protection and management of peat ecosystems) to a depth of 60 cm. This study was conducted in a greenhouse and Laboratory of Physics, Chemistry and Biology Department of Soil, Agriculture Faculty, ULM. This study was began in October 2021 and continued until February 2022. The research method used was a factorial Completely Randomized Design (CRD) with four replications. The factors tested were the water table of the peat at a depth of 0 cm just above the soil surface (T1), 20 cm below the soil surface (T2), 40 cm below the soil surface (T3), and 60 cm below the soil surface (T4). The results of this study showed that the CO2 evolution of peat soil during incubation for 1, 2, 3, 7, 14, 21, and 28 days at a depth of 20 cm was not significantly different from a depth of 40 cm and 60 cm, but significantly different when the groundwater level was right at the surface soil. The CO2 evolution of peat soils at groundwater levels at the soil surface was lower than water levels 20, 40, and 60 cm below the ground.

Microbial abundances and carbon use under ambient temperature or experimental warming in a southern boreal peatland

Organic peat soils occupy relatively little of the global land surface area but store vast amounts of soil carbon in northern latitudes where climate is warming at a rapid pace. Warming may result in strong positive feedbacks of carbon loss and global climate change driven by microbial processes if warming alters the balance between primary productivity and decomposition. To elucidate effects of warming on the microbial communities mediating peat carbon dynamics, we explored the abundance of broad microbial groups and their source of carbon (i.e. old carbon versus more recently fixed photosynthate) using microbial lipid analysis (δ13C PLFA) of peat samples under ambient temperatures and before/after initiation of experimental peat warming (+ 2.25, + 4.5, + 6.75, and + 9 °C). This analysis occurred over a profile to 2 m depth in an undrained, ombrotrophic peat bog in northern Minnesota. We found that the total microbial biomass and individual indicator lipid abundances were stratified by depth and strongly correlated to temperature under ambient conditions. However, under experimental warming, statistically significant effects of temperature on the microbial community were sporadic and inconsistent. For example, 3 months after experimental warming the relative abundance of Gram-negative bacterial indicators across depth combined and > 50 cm depth and Gram-positive bacterial indicators at 20–50 cm depth showed significant positive relationships to temperature. At that same timepoint, however, the relative abundance of Actinobacterial indicators across depth showed a significant negative relationship to temperature. After 10 months of experimental warming, the relative abundance of fungal biomarkers was positively related to temperature in all depths combined, and the absolute abundance of anaerobic bacteria declined with increasing temperature in the 20–50 cm depth interval. The lack of observed response in the broader microbial community may suggest that at least initially, microbial community structure with peat depth in these peatlands is driven more by bulk density and soil water content than temperature. Alternatively, the lack of broad microbial community response may simply represent a lag period, with more change to come in the future. The long-term trajectory of microbial response to warming in this ecosystem then could either be direct, after this initial lag time, or indirect through other physical or biogeochemical changes in the peat profile. These initial results provide an important baseline against which to measure long-term microbial community and carbon-cycling responses to warming and elevated CO2.

Assessment of the effect of peat soil on the content of mobile forms of heavy metals and allelotoxicity in urbanized soils under moisture-loving plants at the Ecological Station of the Russian State Agrarian University – Moscow Timiryazev Agricultural Academy

The article presents the results of studies on the sorption of pollutants by moisture-loving plants when using peat soil under different anthropogenic loads. The comparative cultivation of moisture-loving plants on sod-podzolic soil, typical for this area, and on peat soil revealed their specificity in the sorption of heavy metals: there was a decrease in the content of lead and copper in peat soil under moisture-loving plants. In typical sod-podzolic soil under moisture-loving plants the opposite dynamics was observed. As for the zinc content, it was found that it increased in peat soil under moisture-loving plants, with the exception of reed. The experiment was conducted on the territory of the Ecological Station of the Russian State Agrarian University – Moscow Timiryazev Agricultural Academy in Moscow in 2019‑2022. Thus, moisture-loving plants grown on peat soil as a substrate can be used to reduce the content of mobile forms of heavy metals (lead and copper) in urbanized soils.

Vegetation and Peat Soil Characteristics of a Fire-Impacted Tropical Peatland in Costa Rica

Vegetation and Peat Soil Characteristics of a Fire-Impacted Tropical Peatland in Costa Rica

PYROGENIC CHANGES OF BOG VEGETATION AND PEAT IN WESTERN SIBERIA

Wildfires are an important environmental factor which determines the carbon cycle intensity in mires. The article presents the assessment of the consequences of pyrogenic transformation and the current state of burntout mires in the taiga and forest-tundra zones of Western Siberia 6-8 years after the wildfire, with regard to their microhabitat heterogeneity. Field studies were conducted in 2022 on three mires (a total of 13 post-pyrogenic and pristine plots) and included a total-station survey of the surface, an assessment of the occurrence of species in the grass-dwarf shrub and moss-lichen tiers, sampling for laboratory analysis of the physical properties and botanical composition of peat. Sphagnum mosses, Polytrichum strictum, lichens and dwarf shrubs were considered as recovery indicator species. As a result of the study, it was found that the intensity of pyrogenic transformation is determined by the initial state of bog ecosystem and increases in a row: the hydro forestation site on the Bakchar raised bog - palsa - the Ust-Bakchar raised bog drained for peat extraction. At most of the studied plots, microdepressions were more susceptible to burnout, while hummocks were preserved or only partially burned out. The transformation of peat deposit properties extends beyond the layer directly exposed to burnout, and manifests itself in a decrease in water content, and an increase in ash content, bulk density and degree of humification. At the first stages of post-pyrogenic successions, similar patterns were revealed for the mires of taiga and forest-tundra zones, i.e. an intensive overgrowth with P. strictum. According to the results of the study, it was concluded that the hydroforestation site in the Bakchar bog could possibly restore the species composition of vegetation cover and resume peat accumulation. Irreversible changes in vegetation cover have occurred in the Ust-Bakchar bog, where the restoration of sphagnum mosses does not occur even 20 years after the fire.

Microtopography causes small‐scale variation in harvest and forage quality of high‐yielding silage grassland in northern Germany

AbstractBackgroundLocal sward dieback, especially in grasslands on peat soil, in response to the extreme 2018/2019 drought demonstrates climate vulnerability of intensive grasslands in northern Central Europe.MethodsWe explore the influence of microtopography, that is, the within‐field mosaic of depressions and elevated patches, on soil volumetric moisture content, standing biomass and biomass crude protein (CP) and fibre content in intensively managed grassland on peat soil in a moist year (2021) and a dry year (2022) for quantifying small‐scale spatial heterogeneity within a field.ResultsWe found high within‐field variation in soil moisture, biomass and forage quality and a moisture dependence of productivity that was stronger in the dry year. CP ranged from 10% to 25% within a field, being lower in moist depressions than elevated patches in the wet (but not in the dry) summer.ConclusionsThe moister depressions help to limit the overall productivity decline in dry summers, whereas, in moist summers, the higher dry patches produce more protein‐rich forage than the depressions, where productivity is higher but quality is lower. We recommend adapting grassland management to this heterogeneity through spatially differentiated management regimes in order to better cope with an increasingly drier and more variable climate.

Carbon Accumulation in Peat Soils of Floodplain Mires in the Northeast of the Central Russian Upland

Carbon Accumulation in Peat Soils of Floodplain Mires in the Northeast of the Central Russian Upland

KARAKTERISASI MORFOLOGI DAN UJI ANTIFUNGI ISOLAT JAMUR Trichoderma spp. DARI TANAH GAMBUT TERHADAP PATOGEN PADA JARAK KEPYAR (Ricinus communis L.)

Castor oil (Ricinus communis L.) is an oil producing commodities that plays a role in meeting industrial and economic needs. Infection with the pathogen fungi caused a decrease in the production of castor oil. Biological control using Trichoderma spp. has been widely used. Trichoderma spp. known as one of the benefical biofungicide because it has high antagonistic properties inhibiting the growth pathogenic fungi. The purpose of this study was to obtain isolates and characters as well antifungal test for Trichoderma spp. isolated from peat soil to control pathogen Aspergillus sp. on castor been (Ricinus communis L.). Trichoderma spp. isolated from peat soil in Meranti Islands, Riau. The antagonistic activity the isolates against pathogen Aspergillus sp. was studied in vitro using dual culture and in vivo assay. In this study, six isolates of Trichoderma spp have isolated. Trichoderma sp. GBA5 has the highest growth rate on PDA and TSM medium. Trichoderma sp. GBA3 and Trichoderma sp. GBA4 were most effective in percentage inhibition of mycelial growth of test pathogen i.e 84,55% and 83,71% respectively. In in vivo assay, only Trichoderma sp. GBA5 inhibited pathogen with the percent infected castor capsule was 51.66%.

Growth and yield of Okra (<i>Abelmoschus esculentus</i> L. Moench) treated with vermicompost and eco enzyme in histosol soil

This study explores the efficacy of ecoenzyme and vermicompost on the growth and yield of Okra plants (Abelmoschus esculentus L. Moens). The ecoenzyme, derived from three types of fruit peels and two local vegetable wastes in Central Kalimantan, is proposed as an organic liquid fertilizer to replace chemical alternatives, promoting environmentally friendly agricultural practices. Simultaneously, the incorporation of ecoenzyme, along with vermicompost, is anticipated to enhance the physical, chemical, and biological properties of peat soils, serving as a growth medium for Okra plants. The experimental setup involves a completely randomized design with four stages of POC ecoenzyme and vermicompost administration. Treatments range from a control group (E0V0) to various combinations of ecoenzyme and vermicompost in different doses (E1V1, E2V2, E3V3). Observations, including plant height, leaf characteristics, and fruit metrics, were conducted at multiple intervals. Results indicate that the treatment with 60 ml of ecoenzyme and 125 gr of vermicompost per plant significantly influenced Okra growth and yield. Higher doses, as in V2E2 and V3E3, were deemed excessive. The study suggests further exploration of the interaction between ecoenzymes and vermicompost using a two-factorial complete randomized design for comprehensive insights.

Sifat Kimia Tanah Bergambut dan Tanah Mineral Masam di Bawah Naungan Tanaman Kelapa Sawit

An understanding of land suitability or management such as on peat and mineral soils in oil palm plantation areas is also very necessary as a basis for determining technical cultural actions to be taken in order to ensure the sustainability of the productivity of a land. This research was conducted with the aim of knowing the chemical properties of peat soils in Margasari Village, Candi Laras Utara District, Tapin Regency and mineral soils in Martadah Baru Village, Tambangulang District, Tanah Laut Regency under the auspices of oil palm plantations. The method used in this study was a quantitative descriptive method. The sampling point was determined by purposive sampling by showing the existing canopy in the field. Soil sampling in the field at a depth of 0-30 cm for each type of soil. This research plan is intended to describe soil pH, organic-C, total-N, and available-P. In general peat soils had quite high C-organic content values ​​compared to mineral soils. Changes in organic C affected the properties of the soil. The organic C content in all research locations was categorized as very low to medium, the soil pH is acidic, the total N content was moderate and the available P content was categorized as very low.

Integrated water management practice in tropical peatland agriculture has low carbon emissions and subsidence rates

Hydrological management in the use of peatland for agriculture is the backbone of its sustainability and a critical factor in climate change mitigation. This study evaluates the application of an integrated water management practice known as the “Water Management Trinity” (WMT), implemented since 1986 on a coconut plantation on the eastern coast of Sumatra, in relation to CO2 emissions and subsidence rates. The WMT integrates canals, dikes, and dams with water gates to regulate water levels for both coconut agronomy and the preservation of the peat soil. The WMT has successfully regulated and maintained an average yearly water table depth of −45 to −51 cm below the surface. The methodology involved a closed chamber method for measuring soil CO2 flux using a portable Infrared Gas Analyzer, conducted weekly over a six-month period to cover dry and rainy season at bi-modal climate condition. Subsidence measurements have been ongoing from 1986 to 2022. The results show bare peat soil has heterotrophic respiration CO2 emissions of 7.77 t C–CO2 ha−1 yr−1, while in coconut plantations 7.99 t C–CO2 ha−1 yr−1, similar to emissions in mineral soils. Autotrophic respiration leads to the overestimation of CO2 emissions on peatland and accounts for 212–424% of the total emissions. The cumulative subsidence from 1986 to 2022 is −56.3 cm, with a soil rise of +0.8 cm in 2022, indicating a flattening rate of subsidence. This is characterized by an increase in bulk density at the surface from 0.072 to 0.144 gr/cm3, with approximately 81% of the subsidence being due to compaction. The statistical analysis found no relationship between water table depth and CO2 emissions, indicating that water table depth cannot be used as a predictor for CO2 emissions. In summary, peatland agriculture has a promising future when managed sustainably using an integrated hydrological management system.

Differential degradation dynamics of λ-cyhalothrin in mineral and peat soils: a comparative study under laboratory condition

Dissipation kinetics of λ-cyhalothrin in mineral and peat soils of Semongok (mineral soil) and Sibu (peat soil) farms was investigated in a laboratory incubation experiment under different temperature and moisture conditions at normal and double application dosages. The soil was spiked with λ-cyhalothrin at 5 and 25 µg/g soil, respectively. The soil moisture content was adjusted to 20, 40, and 60% of field capacity and then incubated in three climatic chambers at 15, 25, and 35 °C. Samples were collected at 0, 7, 21, 42, 70, and 105 days and analysed by Gas Chromatography-Electron Capture Detector (GC-ECD). Pesticides from the soil were extracted via a facile-modified QuEChERS method. Recovery studies of λ-cyhalothrin in mineral and peat soils were carried out at 0.05, 0.1, 0.5 and 1.0 µg/g fortification levels. The percentage of recovered amount was in the range of 81.4–95.0% and 81.3–86.5% for mineral and peat soils, respectively which falls within the acceptable recovery range of 70.0–120.0%. Factors i.e., soil carbon content, moisture, temperature, and applied dosage that render the degradation of λ-cyhalothrin in mineral and peat soils were evaluated. Findings showed that faster λ-cyhalothrin degradation took place in soil that contained low organic carbon content (< 12%), low soil moisture (≤ 20%) and incubated under higher temperatures (≤ 35 °C). Degradation of λ-cyhalothrin was described by first-order kinetics in both mineral and peat soils at various conditions. Half-lives of λ-cyhalothrin in mineral soil were shorter compared to peat soil. This is due to its lower carbon content and lower soil organic matter availability. This study provides significant information to the agriculture industry and farmers on the important factors such as soil properties, environmental conditions and application dosage that will influence the fate of pesticides in soil.Graphical abstract