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Lime reaction rate in a container substrate is influenced by temperature and moisture, which are factors that vary between batches of substrate during manufacturing, storage, and crop production. The effects of temperature and moisture on the duration required to achieve a stable substrate-pH are useful information for substrate companies and growers, as well as a key component when modeling lime reaction over time. The pH of a 70 peat : 30 perlite (by volume) substrate was quantified over time under a range of different storage temperature (1.9 to 33.3°C) and substrate volumetric water content (VWC, 0.168 to 0.568 L of H2O/L of substrate). The lime source was a horticultural dolomitic carbonate limestone screened to the fraction that passed through a 100 US mesh but was retained on a 200 US mesh (0.075–0.15 mm) incorporated at 2.67 g·L−1 of substrate. Experiments provided two data sets for calibration and validation. Lime reaction rate increased with increasing substrate temperature and substrate moisture level. The duration required to reach a target substrate-pH value of 6.0 was used to indicate 90% of maximum pH effect from lime. Duration varied from 4 days with the combined high temperature (20.6 and 33.3 °C) and high VWC (0.468 and 0.568 L H2O/L of substrate) to 53 days with low temperature (1.9 °C) and low VWC (0.168 L H2O/L of substrate) for the calibration data set. At an example low VWC of 0.168 L of H2O/L of substrate, the duration required to reach substrate-pH 6.0 at 1.9, 7.8, 10, 20.6, and 33.3°C was 53, 38, 34, 23, and 17 days, respectively. Similarly, if the temperature was held constant at 33.3°C, reducing VWC from 0.568 L H2O/L to 0.128 L H2O/L would decrease lime reaction rate from 100% to 21%, requiring five times the duration to reach an equilibrium pH. Results can be used to compare the relative effects of moisture and temperature on lime reaction rate for substrate manufacturers and growers. [ABSTRACT FROM AUTHOR]

Coastal wetlands adapt to rising seas via feedbacks that build soil elevation, which lead to wetland stability. However, accelerated rates of sea-level rise can exceed soil elevation gain, leading to wetland instability and loss. Thus, there is a pressing need to better understand regional and landscape variability in rates of wetland soil elevation change. Here, we conducted a regional synthesis of surface elevation change data from mangrove forests and coastal marshes in the iconic Greater Everglades region of south Florida (USA). We integrated data from 51 sites in which a total of 122 surface elevation table-marker horizon (SET-MH) stations were installed. Several of these sites have been periodically monitored since the 1990s and are among the oldest SET-MH datasets in the world. Rates of surface elevation change ranged from −9.8 to 15.2 mm year−1, indicating some wetlands are keeping pace with sea-level rise while others are at risk of submergence and conversion to open water. Vertical accretion rates ranged from 0.6 to 12.9 mm year−1, and subsurface change rates ranged from −13.5 to 8.6 mm year−1. Rates of surface elevation change were positively related to subsurface change but not vertical accretion. There were no significant relationships between rates of surface elevation change and elevation (NAVD 88) or rates of sea-level rise. Site-specific examples indicate that hurricanes, plant productivity, hydrologic exchange, and proximity to sediment and nutrient inputs are critical but confounding drivers of surface elevation change dynamics in the Greater Everglades region. Collectively, our results reinforce the value of long-term SET-MH data that incorporate spatial variability for advancing understanding of surface elevation change dynamics in coastal wetlands. [ABSTRACT FROM AUTHOR]

To sustain the increasing needs of a rapidly growing population, agriculture has relied on the use of synthetic fertilizers to intensify its production. However, the economical, environmental and health impacts associated with their use have raised significant concerns, especially given the scarcity of phosphorus. Utilizing nutrient-recovered materials like struvite can enhance circularity in agriculture and reduce its reliance on synthetic fertilizers. The objective of this study was to assess the implementation of struvite as a complete substitute to triple superphosphate, for radish and spinach seedling production and early growth, with or without supplementary fertigation. In addition, two rates of struvite were examined (0.68 and 1.37 g L−1 substrate) to evaluate its solubility. In the germination of radish, struvite had similar performance with conventional fertilization, while in spinach, the use of struvite decreased mean germination times. Both plants maintained comparable growth, chlorophyll content and antioxidant capacity when struvite was used, in comparison to conventional fertilizers. However, higher struvite rates under un-fertigated conditions significantly increased the chlorophyll b and total chlorophylls in the spinach, while phenolics and flavonoids decreased, contingent on the fertigation applications. In the radish, struvite maintained similar MDA and H2O2 levels to conventional fertilization, while decreases occurred in the spinach, with the application of ST1 under un-fertigated conditions, compared with conventional fertilization. The P and N contents of the plants were also affected, though these effects varied depending on the plant species, fertigation applications and struvite rates. This variance can be attributed to the characteristics of struvite, the plant species and the cultivation practices. The results of this study suggest that struvite can be successfully implemented in seedling production, establishing significant prospects for its commercialization and use in nurseries. [ABSTRACT FROM AUTHOR]

Sequential (S) and equal-time (ET) methods were applied to assess the temperature sensitivity of respiration of peat soils in different terrestrial ecosystems: southern tundra, northern taiga, and mixed coniferous–broadleaved forests. The Q10 values varied widely (1.3–4.8) and in case of the ET method decreased from northern to temperate latitudes. In the cold range (5–15°С), Q10 increased from the southern tundra (3.5) to the northern taiga (4.8) and then sharply decreased in the zone of mixed forests (2.5). Meanwhile, warm range (15–25°С) showed a clear decline of Q10 from northern to temperate latitudes: southern tundra (2.6) > northern taiga (1.6) > coniferous–broadleaved forests (1.3). Application of the S method resulted in low variability of Q10 values. Our results demonstrate a higher temperature sensitivity of the respiration of peat soils in northern latitudes as compared to that in the temperate zone. The Q10 values obtained in this study can be useful for calibration of regional carbon cycle datasets that consider the contribution of peat soils. [ABSTRACT FROM AUTHOR]

Bulk density (Db) and subsequent physical properties are determined by the substrate and packing method. Packing method is the way one fills and compresses a substrate within a given volume. Bulk density produced in the laboratory may not align with “expected” published ranges due to variations in packing. Additionally, it is unknown if ranges identified as “typical” using a small volume sample ring reflect Db occurring in larger production size containers packed using commercial potting practices. Therefore, our objectives were to 1) emulate nursery practices and document the Db associated with a potted 2.8-L (#1) container, 2) develop and test the new “shim and compression” method to determine if it consistently packs sample rings to a Db commensurate with that of a 2.8-L nursery container, and 3) demonstrate how static physical properties are affected by the new “shim and compression” sample ring packing method compared with the traditional bench top tap method. When emulating nursery potting practices with 100% pine bark, coir, and peat, and blends of each, Db ranged from 0.08 g.cm-3 (coconut coir) to 0.17 g.cm-3 (pine bark). We used an espresso tamp and shims to pack the aforementioned substrates in sample rings. The Db achieved using a range in number of presses and discs was largely dependent on the substrate, but the desired Db was consistently achieved for each substrate. There was no effect of disc number on Db (P 5 1.000) for any substrate. There was no effect of tamp number (P $ 0.0602) for all substrates except peat-amended, for which five tamps yielded a greater Db than one tamp (P 5 0.0324). In an experiment in which a different technician who was accustomed to the conventional benchtop tap packing method performed both methods, method influenced Db (P < 0.0001), and the conventional method more closely attained the target Db. To our knowledge, this is the only report of Db observed in commercial container production facilities (i.e., “native”). [ABSTRACT FROM AUTHOR]

[Objective] The aim of this study was to explore the feasibility of biochar replacing peat in the cultivation of Calendula officinalis. [Method] The pot experiment was conducted for 4 treatments of replacing 5% (BS5), 10% (BS10), 15% (BS15), and 20% (BS20) peat with biochar using a compound substrate of peat, perlite, and vermiculite as the control (CK). The changes in growth and ornamental characteristics of Calendula officinalis and their correlation with substrate properties were analyzed. [Result] The growth of Calendula officinalis was promoted and its ornamental characters were improved after partial replacement of peat with biochar. The shoot dry weight and root dry weight of BS5-BS20 treatments were 1.90-3.31 and 1.77-2.38 times higher than those of CK, respectively. The carotenoids contents of BS10-BS20 treatments were 1.76-6.90 times higher than those of CK. The membership function analysis showed that growth and ornamental characters of Calendula officinalis were the best under BS15 treatment. Adding biochar increased total porosity of the compound substrate by 4.14%-15.26% and increased contents of available phosphorus and potassium by 39.33%-148.68% and 335.07%-850.25%, respectively. The activities of sucrase, urease and phosphatase were increased by 12.86%-35.24%, 14.85%-65.24% and 18.95%-33.33%, respectively. Redundancy analysis (RDA) showed that main physical and chemical factors affecting growth and ornamental characters of Calendula officinalis were available phosphorus, bulk density, and aeration pores. The main biological factors were phosphatase activity, urease activity, microbial biomass nitrogen, and fungi. [Conclusion] It was feasible to replace 5%-20% peat with biochar to cultivate Calendula officinalis. Biochar promoted the growth of Calendula officinalis and enhanced its ornamental value by improving physical, chemical and biological properties of the compound substrate. [ABSTRACT FROM AUTHOR]

Sphagnum mosses are a keystone peatland species whose ecohydrology governs carbon sequestration processes in many peatlands. Globally, there are ~380 Sphagnum species that occupy a wide range of ecohydrological niches (microforms) based on their ability to grow at or above the water table, broadly grouped by hummock (furthest from water table), lawn, and hollow (closest to water table) microforms. The further from the water table a given species can grow is controlled by the ability to effectively retain and transmit water to the capitula (growing surface) during dry periods. However, Sphagnum species can have a relatively plastic ecohydrological niche, often occupying different niches (microforms) in different environments. We used numerical modelling parameterized by previous field and laboratory studies to compare the hydrological function between Sphagnum hummock, lawn, and hollow microforms. We determined (a) how two different organizations of a hummock of Sphagnum fuscum and (b) a lawn or hollow of S. magellanicum (S. divinum/S. medium) or S. rubellum differed between two different overarching climates (sub‐humid boreal and humid temperate). The hydrological function, expressed as the cumulative water fluxes, was similar between species and ecohydrological microform (water table position) when water was plentiful, despite differences in soil hydraulic properties of the same species, but began to diverge during a prolonged simulated dry period (30‐day drought). These results suggest a single species of Sphagnum moss can exhibit a wide range of soil hydraulic properties (i.e., sphagnum morphology) but have essentially the same consequential hydrology. Only the S. fuscum from the sub‐humid climate was hydrologically stressed enough to show differences in the simulated evaporation rates. This study highlights the need for more physical research to determine the sensitivity of Sphagnum spp.'s soil hydraulic properties to overarching hydroclimatic factors so that we can more effectively incorporate these processes into large‐scale numerical modelling efforts. [ABSTRACT FROM AUTHOR]

Studies of permafrost agradation within peat mires leading to palsa growth and palsa dynamics during the Holocene are important for predicting the future of permafrost in a changing climate. The radiocarbon age of peat cover and stable isotope composition of the ice cores of palsas near Eletsky settlement, north‐east of the European part of Russia, were studied. Palsa growth was the most active between 8 and 5 cal ka BP. The main sources for ice core formation were precipitation‐fed surface and suprapermafrost waters. It is assumed that the isotope composition of the initial water was isotopically depleted compared with modern surface waters, which may be explained by general climate cooling during earlier stages of palsa growth (response to the 8.2 ka cooling event). The ice cores of the studied palsas were formed during the freezing of water in semi‐closed conditions, mainly by the segregation mechanism during permafrost agradation, thickness of the ice lenses and ice volume could depend on freezing rates and water supply. The upper part of the palsa ice core experienced deep thawing and could be saturated with meteoric water; repeated freezing of this part of the ice core likely occurred in closed system conditions. [ABSTRACT FROM AUTHOR]

The application and promotion of biodegradable plastics are hindered by the imbalance between their mechanical and degradation performance imbalance, as well as high costs. Herein, a series of poly(ethylene adipate‐co‐terephthalate) (PEAT) copolyesters with excellent mechanical and degradation properties are synthesized by one‐step melt polycondensation. The influence of the proportion of aliphatic groups in the molecular chain on the structure and properties, especially the degradation performance, of the copolyesters was studied. The molecular chain flexibility and degradability of PEAT increases with increasing of adipic acid content and decreasing of ET fragment length (LET). The comprehensive mechanical properties of PEAT60 can be comparable to traditional packaging material poly(butylene adipateco‐terephthalate) (PBAT). The degradation performance of PEAT can be adjusted the molecular chain structure. PEAT with LET < 3 exhibit degradation performance, and PEAT with LET < 2.2 exhibit significant degradation acceleration. The excellent mechanical and degradable properties of PEAT copolyester make it expected to be used in degradable packaging and other fields to help solve plastic pollution, while its lower cost will aid in the promotion of degradable materials. [ABSTRACT FROM AUTHOR]

Peatlands across the world are vital carbon stores. However, human activities have caused the degradation of many sites, increasing their greenhouse gas emissions and vulnerability to wildfires. Comprehensive monitoring of peatlands is essential for their protection, tracking degradation and restoration, but current techniques are limited by cost, poor reliability and low spatial or temporal resolution. This paper covers the research, development, deployment and performance of a resilient and modular multi-purpose wireless sensor network as an alternative means of monitoring peatlands. The sensor network consists of four sensor nodes and a gateway and measures temperature, humidity, soil moisture, carbon dioxide and methane. The sensor nodes transmit measured data over LoRaWAN to The Things Network every 30 min. To increase the maximum possible deployment duration, a novel datastring encoder was implemented which reduced the transmitted datastring length by 23%. This system was deployed in a New Forest (Hampshire, UK) peatland site for two months and collected more than 7500 measurements. This deployment demonstrated that low-cost sensor networks have the potential to improve the temporal and spatial resolution of peatland emission monitoring beyond what is achievable with traditional monitoring techniques. [ABSTRACT FROM AUTHOR]

Pile-supported embankments have been recognized as long-standing solutions for construction in compressible soft soils. Instead of improving the physical and mechanical properties of the soft soil, this method emphasizes efforts to transfer the embankment load to a competent layer below the compressible layer. Mortar column inclusion (inklusi kolom mortar or IKM) is recognized as one of the rigid inclusions in a pile-supported embankment. The IKM combined with a load transfer platform (LTP) has been widely utilized to support embankments. Studies on pile-supported embankments have generally focused on the arching mechanisms and geotextile tensile force evaluations; however, most of these investigations were conducted on soft cohesive soils. The application of pile-supported embankment on peat has rarely been studied comprehensively. This study presents a full-scale trial embankment on peat in West Sumatra, Indonesia. The 8-m-high trial embankment was supported by a series of IKM piles and a geotextile-reinforced LTP layer; instruments were then installed in the embankment, ground, LTP, geotextile, and IKM. These instruments included a series of vibrating wire earth pressure cells, vibrating wire strain gages, fiber optic sensors, vibrating wire piezometers, settlement profilers, settlement plates, and inclinometers. The instruments provided observations on the ground movements, IKM displacements, and stresses in the materials. Comprehensive evaluations from field monitoring allowed study of load transfer via the arching mechanism, deformation pattern, and IKM performance in peat. Finite element analyses (FEAs) were also conducted for comparison and verification. The field monitoring results and FEAs showed good agreement, thereby demonstrating the potential of the proposed ground improvement method for embankment construction on peat. [ABSTRACT FROM AUTHOR]

Protecting the environment from harmful substances (carbon oxides, nitrogen oxides, soot products, etc.) is one of the pressing issues of our time. This article discusses specific topics related to the need to reduce carbon dioxide emissions into the atmosphere, which are generated during biomass gasification, Fischer-Tropsch synthesis, and other processes. The article also identifies alternative methods for producing valuable petrochemical products, which significantly reduce gas emissions into the atmosphere. [ABSTRACT FROM AUTHOR]

Numerous studies have been conducted in order to utilize the olive pomace, the solid waste left over from the oil processing of olives, which is widely cultivated, especially in Mediterranean countries, and to consider it a raw material that has added value instead of being considered waste. Some of these research are focused on establishing the re-utilization of olive pomace in agricultural production. Although some studies have reported that olive pomace can be utilized as fertilizer, soil improvement regulator, solid media culture, and even mulching material, this study was carried out due to the lack of sufficient scientific data on whether or not this material can be used as a growth medium in the cultivation of potted grapevine saplings. The study was carried out by growing ungrafted grapevine saplings of Vitis vinifera L. cv. Hatun Parmağı on media with peat and olive pomace at different ratios for six months, and then some vegetative growth parameters were examined. Due to the elevated olive pomace ratios in the growth medium, shoot and root growth of the grapevine saplings were restricted. The chlorophyll index and root fresh weight decreased dramatically when more than 25% (v/v) and 20% (v/v) crude pomace were available in the growth medium, respectively. Moreover, the availability of olive pomace in the medium significantly reduced shoot length, number of leaves, shoot weight, and leaf weight of grapevine saplings, regardless of the amount of olive pomace. However, it was found that 15% (v/v) or less of crude olive pomace could be utilized in growth medium mixtures when growing potted grapevine saplings; however, higher ratios would prevent the saplings from attaining marketable quality. While designing new studies, examining different grape varieties, fruit species, and lower olive pomace ratios would contribute to new and more comprehensive findings on the utilization of olive pomace in growing potted saplings. [ABSTRACT FROM AUTHOR]

This study investigated the effects of substrates composed of various ratios of wood fiber and peat (0, 25, 50, 75, and 100% peat (v/v)) mixed with different amounts of lime (0, 2, 4, 6, and 8 g L−1) and start fertilizer (0, 2, and 4 g L−1 Multimix) on the growth and biomass accumulation of petunia (Petunia x hybrida Vilm 'Finity F1 Purple') and basil (Ocimum basilicum L. 'Marian') in an ebb-and-flow greenhouse system. Growth parameters included plant height, weight, canopy diameter, and chlorosis symptoms for petunia, along with substrate pH and EC measurements. Petunia showed optimal growth in substrates with higher peat content, while basil produced satisfactory biomass across a pH range of 5–7 regardless of substrate type. Optimal petunia cultivation in 100% wood fiber required a significant dose of start fertilizer without lime. Monitoring pH and EC using pour-through and press methods revealed a pH decrease in substrates with added start fertilizer, while substrates with higher wood fiber content were less acidic. Substrates with over 50% (v/v) wood fiber without lime showed a rapid pH increase over five weeks. The pour-through method generally underestimated EC values compared to the press method. These findings contribute to optimizing the wood fiber/peat blends for sustainable horticulture. [ABSTRACT FROM AUTHOR]

The rapid growth of the horticultural industry has increased demand for soilless cultivation substrates. Peat, valued for its physical and chemical properties, is widely used in soilless cultivation. However, peat is non-renewable, and over-extraction poses serious ecological risks. Therefore, sustainable alternatives are urgently needed. Ammonium incubation, a novel method to reduce phytotoxicity, offers the potential for green waste, a significant organic solid waste resource, to substitute peat. This study optimized the ammonium incubation process to reduce green waste phytotoxicity. It systematically examined different nitrogen salts (type and amount) and environmental conditions (temperature, aeration, duration) affecting detoxification efficiency. Results show a significant reduction in phytotoxicity with ammonium bicarbonate, carbonate, and sulfate, especially carbonate, at 1.5%. Optimal conditions were 30 °C for 5 days with regular aeration. Under these conditions, ammonium salt-treated green waste significantly reduced total phenolic content and stabilized germination index (GI) at a non-phytotoxic level (127%). Using treated green waste as a partial peat substitute in lettuce cultivation showed promising results. This low-cost, low-energy method effectively converts green waste into sustainable peat alternatives, promoting eco-friendly horticulture and environmental conservation. [ABSTRACT FROM AUTHOR]

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The paper considers the possibility of determining the age and correlating peat sections by solving the inverse problem of magnetostratigraphy based on the findings of comprehensive (palaeomagnetic, petromagnetic, microprobe, and radiocarbon) studies on peats of the «Tyapka» and «Chlya» peat sections in the Lower Amur region. For this purpose, we used the values of relative paleointensity calculated following the technique described by Bagina-Petrova. There is no difference in the rate of magnetization fixation among studied peat samples, and the age of magnetization is comparable to the age of the peat deposits itself. The solution of the inverse problem of magnetostratigraphy using the values of relative paleointensity can be used to correlate peat sections among themselves and to estimate the rate of peat accumulation in different periods of the Holocene, even in the absence of radiocarbon dating for one of the correlated sections.

The paper presents the results of a comparative assessment of the sorption characteristics of regional natural raw materials of organic origin: sphagnum moss (Sphаgnum palustre L.), fucus algae (Fucus vesiclousus), a composite based on them and peat in comparison with the synthetic sorbent OilSorb used in the practice of emergency rescue units to eliminate accidental oil spills. Experimental data have been obtained on potential pollutants in the Barents Sea (oil ARCO and diesel fuel) and the water capacity of sorbents for standard conditions at temperatures of 21–23 °C according to GOST 33627-2015 and in the temperature range of 10–12 °C typical for the summer period on the Kola Peninsula. The sorption characteristics of the materials under study have been evaluated in the "sea water – petroleum product" system, which simulates a real oil spill in the marine area. Tests in a model system simulating real conditions demonstrate significant changes in the efficiency of using sorption materials shown by them under standard conditions. The study has established the dynamics of the distribution of sorbed oil products and water in the materials under consideration, as well as residual oil products in the water of the "sea water – ARCO oil" and "sea water – diesel fuel" systems at different exposure times. During an exposure time of 30, 60, 90 minutes under the conditions of a system simulating a real oil spill in the water area, the material based on sphagnum moss has the most effective and time-stable indicators of sorption of oil products.

Peat is an organic mineral resource. Peat contains a large amount of humic acid, and extracting humic acid from peat is a way to efficiently utilize peat. This article mainly studies the effects of using woody, herbaceous, and mossy peat as raw materials on the yield, content, and especially molecular structure of humic acid extraction, including that the oxygen-containing functional groups of humic acids, aromatic carbon content, microcrystalline structure, carbon chain structure, and degree of aromatization. The results showed that the highest yield of humic acid in woody peat was 54.33%, the yield of humic acid in herbaceous peat and mossy peat are relatively low, at 44.67% and 15.00%, respectively. while the woody peat humic acid has the lowest content, that is 38.38%. The content of humic acid in herbaceous peat was 77.33%. and the content of humic acid in mossy peat is 57.85%. Through comprehensive consider, herbaceous peat is more suitable for extracting humic acid. At the same time, this article studies the molecular structures of three peat humic acids and concludes as follows. Woody peat humic acid has the highest degree of aromatization, the highest content of benzene ring, and more functional groups such as methyl, phenol, aromatic ether, carbonyl, and hydroxyl groups. The content of methoxy and methylene groups in herbaceous peat humic acid is relatively high. Through XPS characterization analysis, it was found that the main forms of oxygen element in humic acid are C = O, C-O, and -COOH, without inorganic oxygen. The humic acid extracted from different types of peat has significant differences in yield, purity, and functional group content. Compared to woody peat and mossy peat, herbaceous peat is the most suitable raw material for extracting humic acid from peat. [ABSTRACT FROM AUTHOR]

Balneology is one of the oldest fields of medicine related to the use of natural raw materials (medicinal waters, medicinal gases, peloids, climatic values) in the treatment, prevention, and rehabilitation of many diseases but also increasingly in cosmetology. Currently, balneotherapy (spa therapy) combines tradition and modernity. The interest in spa treatments, the popularity of a healthy lifestyle, as well as the constant search for active substances of a natural origin for cosmetics make peloids, medicinal, and mineral waters very popular in the cosmetics industry. The main aim of this review was to present current, scientifically proven knowledge about the potential use of peat, huic substances, and sulfurous water in cosmetology. The work describes the potential possibilities of using medicinal waters, especially sulfurous waters, as well as peats and humic compounds, which are the source of active substances with biological activity e.g., antibacterial, anti-inflammatory, and antioxidant, and possess a positive effect on psoriasis, atopic dermatitis, or acne. The therapeutic effects of these substances have been well documented in the literature; however, the validity of their use in cosmetology requires further confirmation. [ABSTRACT FROM AUTHOR]

Excess CO2 accumulated in soils is typically transported to the atmosphere through molecular diffusion along a concentration gradient. Because of the slow and constant nature of this process, a steady state between peat CO2 production and emissions is often established. However, in peatland ecosystems, high peat porosity could foster additional non-diffusive transport processes, whose dynamics may become important to peat CO2 storage, transport and emission. Based on a continuous record of in situ peat pore CO2 concentration within the unsaturated zone of a raised bog in southern Canada, we show that changes in wind speed create large diel fluctuations in peat pore CO2 store. Peat CO2 builds up overnight and is regularly flushed out the following morning. Persistently high wind speed during the day maintains the peat CO2 with concentrations close to that of the ambient air. At night, wind speed decreases and CO2 production overtakes the transport rate leading to the accumulation of CO2 in the peat. Our results indicate that the effective diffusion coefficient fluctuates based on wind speed and generally exceeds the estimated molecular diffusion coefficient. The balance between peat CO2 accumulation and transport is most dynamic within the range of 0–2 m s−1 wind speeds, which occurs over 75% of the growing season and dominates night-time measurements. Wind therefore drives considerable temporal dynamics in peat CO2 transport and storage, particularly over sub-daily timescales, such that peat CO2 emissions can only be directly related to biological production over longer timescales. [ABSTRACT FROM AUTHOR]

Effective planning and management strategies for restoring and conserving tropical peat swamp ecosystems require accurate and timely estimates of aboveground biomass (AGB), especially when monitoring the impacts of restoration interventions. The aim of this research is to assess changes in AGB and evaluate the effectiveness of restoration efforts in the North Selangor Peat Swamp Forest (NSPSF), one of the largest remaining peat swamp forests in Peninsular Malaysia, using advanced remote sensing techniques. A Random Forest machine learning method was employed to upscale AGB estimates, derived from a 'LiDAR AGB model', to larger landscape-scale areas with Sentinel-2 spectral and textural variables. The time period under investigation (2015–2018) marked a concentrated phase of restoration and regeneration efforts in NSPSF. The results demonstrate an overall increase in tropical peat swamp AGB during these years, where the total amount of estimated AGB stored in NSPSF increased from 19.3 Tg in 2015 to an estimated 19.8 Tg in 2018. The research found that a tailored variable selection approach improved predictions of AGB, with optimised input variables (n = 62) and parameter adjustments producing a good plausible result (R2 = 0.80; RMSE = 55.2 Mg/ha). This paper concludes by emphasizing the importance of long-term studies (>5 years) for analyzing the success of tropical peat swamp restoration methods, with a potential for integrating remote sensing technology. [ABSTRACT FROM AUTHOR]

Phosphorus (P) retention in soils in the presence of organic matter (OM) has been, for years, a topic with no clear conclusions. Considering the important ecological functions of peatlands, the objective of this study is to examine the role of OM transformation in relation to P status in Histosols in the Oder Valley (Poland). Basic physical and chemical properties and the following P forms were determined in the organic horizons of 5 soil profiles from two habitats (eutrophic and dystrophic): total (Pt) and organic P (Po), available P (PM3), easily soluble P (PCaCl2), water-soluble P (PW), and fraction of Po in humic (Po_HA) and fulvic (Po_FA) acids after extraction with 0.5 mol L−1 NaOH. The results were statistically verified in both examined habitat groups separately. The higher values of mobile P forms were found in the upper organic horizons released from OM constituents as a result of their decomposition. The role of OM in P retention was strongly related to the activity of humic substances (HS): a higher Po percentage (6.9–99.4% of Po) was observed in dystrophic, whereas a lower (9.3–28.6% of Po) was observed in eutrophic Histosols. Humic acids played a dominant role in P retention compared to fulvic acids in most peat horizons, especially at pH < 5. The role of HA and FA in P retention was clearly dependent on forms found only in eutrophic Histosols. The important role of FA in P retention during OM transformation was confirmed by negative correlations between Po_FA and macronutrient ratios in both soil groups. The results confirm the variable role of OM in P retention, depending on soil environmental conditions and OM type (peat and moorsh). This may have important applications not only in areas of natural importance, for which the release of mobile P forms may be a threat, but also in agricultural areas where, for a change, we struggle to increase P availability. [ABSTRACT FROM AUTHOR]

Peatlands store large amounts of carbon (C), a function potentially threatened by climate change. Peatlands composed of vascular cushion plants are widespread in the northern and central high Andes (páramo, wet and dry puna), but their C dynamics are hardly known. To understand the interplay of the main drivers of peatland C dynamics and to infer geographic patterns across the Andean regions, we addressed the following question: How do topography, hydrology, temperature, past climate variability, and vegetation influence the C dynamics of these peatlands? We summarize the available information on observed spatial and inferred temporal patterns of cushion peatland development in the tropical and subtropical Andes. Based on this, we recognize the following emerging patterns, which all need testing in further studies addressing spatial and temporal patterns of C accumulation: (1) Peatlands in dry climates and those in larger catchments receive higher sediment inputs than peatlands from wet puna and páramo and in small catchments. This results in peat stratigraphies intercalated with mineral layers and affects C accumulation by triggering vegetation changes. (2) High and constant water tables favor C accumulation. Seasonal water level fluctuations are higher in wet and dry puna, in comparison with páramo, leading to more frequent episodes of C loss in puna. (3) Higher temperatures favor C gain under high and constant water availability but also increase C loss under low and fluctuating water levels. (4) C accumulation has been variable through the Holocene, but several peatlands show a recent increase in C accumulation rates. (5) Vegetation affects C dynamics through species‐specific differences in productivity and decomposition rate. Because of predicted regional differences in global climate change manifestations (seasonality, permafrost behavior, temperature, precipitation regimes), cushion peatlands from the páramo are expected to mostly continue as C sinks for now, whereas those of the dry puna are more likely to turn to C sources as a consequence of increasing aridification. [ABSTRACT FROM AUTHOR]

The paper presents the results of comprehensive (microprobe, paleomagnetic and magnetic) studies on peats from the Tyapka peat section (Russian Far East). Radiocarbon dating placed the start of peat formation at ∼11.7 ky B.P. The principle carriers of magnetization were found to be magnetite, to a lesser extent hematite and, possibly, greigite. The relative paleointensity values obtained through calculations are in good agreement with the literature data. Intervals with negative inclinations of the magnetization vector were identified in peats, which most likely correspond to geomagnetic excursions in the Holocene. The research constrained the duration of the geomagnetic excursions, as well as the geomagnetic field intensity behavior not typical for such variations. [ABSTRACT FROM AUTHOR]

Measurements of net primary productivity (NPP) and litter decomposition from tropical peatlands are severely lacking, limiting our ability to parameterise and validate models of tropical peatland development and thereby make robust predictions of how these systems will respond to future environmental and climatic change. Here, we present total NPP (i.e., above‐ and below‐ground) and decomposition data from two floristically and structurally distinct forested peatland sites within the Pastaza Marañón Foreland Basin, northern Peru, the largest tropical peatland area in Amazonia: (1) a palm (largely Mauritia flexuosa) dominated swamp forest and (2) a hardwood dominated swamp forest (known as 'pole forest', due to the abundance of thin‐stemmed trees). Total NPP in the palm forest and hardwood‐dominated forest (9.83 ± 1.43 and 7.34 ± 0.84 Mg C ha−1 year−1, respectively) was low compared with values reported for terra firme forest in the region (14.21–15.01 Mg C ha−1 year−1) and for tropical peatlands elsewhere (11.06 and 13.20 Mg C ha−1 year−1). Despite the similar total NPP of the two forest types, there were considerable differences in the distribution of NPP. Fine root NPP was seven times higher in the palm forest (4.56 ± 1.05 Mg C ha−1 year−1) than in the hardwood forest (0.61 ± 0.22 Mg C ha−1 year−1). Above‐ground palm NPP, a frequently overlooked component, made large contributions to total NPP in the palm‐dominated forest, accounting for 41% (14% in the hardwood‐dominated forest). Conversely, Mauritia flexuosa litter decomposition rates were the same in both plots: highest for leaf material, followed by root and then stem material (21%, 77% and 86% of mass remaining after 1 year respectively for both plots). Our results suggest potential differences in these two peatland types' responses to climate and other environmental changes and will assist in future modelling studies of these systems. [ABSTRACT FROM AUTHOR]

The Late Viséan (mid-Mississippian) anatomically preserved flora from Pettycur, Fife, Scotland is one of the most significant plant assemblages (lagerstätte) from this period anywhere in the world. It has been known from the later 19th century, mainly from loose limestone blocks found on the beach. Thin sections of limestones showing outstanding permineralised plants offered a number of the most eminent British palaeobotanists of their day to describe many of the plants. Most of the thin sections were made commercially so that an understanding of the formation of the deposit as a whole proved difficult. The peel technique developed in the 1950s allowed large slices of limestone to be peeled but only small pieces of the peels were ever mounted and studied by the new authors. Large collections (more than 100) of loose blocks on the beach and from in situ from within basaltic lava flows by the author and colleagues from the late 1970s onwards have been slabbed and peeled and provide the opportunity for new studies and an assessment of the plant assemblages and possible communities present. At least 25 plant organ species are present representing more than 13 whole plant species. Of particular significance is the occurrence of the four main lycopsid tree types that dominate later Pennsylvanian peats and the occurrence of five ferns. It is shown also that a number of the plants may also be preserved as charcoal, especially zygopterid ferns such as Metaclepsydropsis. Of particular importance is the occurrence of true permineralised peats that provide evidence of the botanical composition of the earliest peat-forming mire at a time of rapid global change with a sudden fall of atmospheric CO 2 and rise in O 2 that would have also had an effect upon wildfire systems. [ABSTRACT FROM AUTHOR]

The article investigates the effect of different media compositions on culantro, or Eryngium foetidum, under pot cultivation in Sikkim, India. The experiment observes the outcomes of media combinations of cocopeat, vermiculite, vermicompost and organic manure with soil as potting media, measured by plant height, leaf area, fresh weight, flower stalk length and diameter, as well as water holding capacity, aeration, uptake of nutrients, shelf of leaves, and organoleptic scores.

A comprehensive paleoecological study of permafrost peat deposits from three locations in the middle reaches of the Yuribei River in the subzone of modern subarctic shrub tundra of the Yamal Peninsula has been performed. Based on the results of palynological and carpological methods and of radiocarbon dating, the changes in regional and local vegetation and climatic conditions of Central Yamal in the Late Glacial and the Postglacial periods are reconstructed. It is found that shrubby tundra with Betula nana was widespread in this area under climatic conditions close to modern ones in the Younger Dryas about 12.6–11.7 cal ka BP. The penetration of tree species (Betula sect. Betula, Picea obovata, and Larix sibirica) and accompanying boreal herbaceous plants began due to more favorable climatic conditions during the Early Holocene warming about 10.2–9.7 cal ka BP. The most favorable conditions for the growth of birch tree, larch, and spruce existed in Central Yamal in the Early and the Middle Holocene in the range of 10.2–4.4 cal ka BP. At that time, open woodlands or even closed forests were common, and the climate was much warmer than the modern one. Forest vegetation degraded and open landscapes with tundra communities were formed at the end of the Middle Holocene (4.5–4.4 cal ka BP). The climatic conditions became similar to modern ones. [ABSTRACT FROM AUTHOR]

The growing demand for grapevine planting materials, due to growing global viticulture, is promoting research studies to improve vineyard sustainability. In greenhouse nurseries, peat is the most common growing medium component used although is an expensive and non-renewable material. Indeed, the reduction of peat exploitation is receiving great attention, and currently, several materials are being investigated as peat substitutes for composing the cultivation substrates. Biochar, a carbon-rich, recalcitrant charred organic co-product of the pyrolysis or gasification process, has emerged as a potentially promising replacement for soilless substrates in nursery plant material propagation. Although several studies carried out at greenhouse nurseries have shown that biochar, can improve plant growth, only a few studies have focused on the production of grapevine plant material. To fulfil this knowledge gap and push forward the sustainability of the nursery sector, we evaluated above and below-ground morpho-physiological traits of one-year-old potted grapevine cuttings growing with 30% volume of four different biochar types (i.e., from pyrolysis and gasification) mixed with commercial peat. The present study shows that biochar can be used in growing media mixes without adverse effects on roots, improves soil water retention and leaf water potential, and improves the effects on soil microbiology. [ABSTRACT FROM AUTHOR]

Peat is a highly soft soil that possesses low shear strength due to the presence of organic content and a high amount of moisture content. In the present study, the peat is stabilized to enhance the strength with fly ash with different percentages of 3, 6, 9, 12, and 15% and reinforced with nylon fiber with 0.5, 1.0 and 1.5% to investigate the performance of peat. The strength of fly ash and fiber-treated peat is compared with cement-treated peat. The Compaction, California bearing ratio (CBR), Unconfined compressive strength (UCS) and Unconsolidated Undrained Triaxial (UU Triaxial), Freezing & Thawing (F&T) tests were used for evaluating the strength properties of peat. The UCS value increases to 280 kPa from 60 kPa at 12% of fly ash content, but at 15% cement content it was increased up to 370 kPa. The UCS value of peat stabilized with 12% of fly ash and reinforced with 1% of fiber obtained as 360 kPa. The CBR also increased to 9.3 from 2.5% for stabilized peat (12% fly ash) and reinforced fiber (1%) in soaked condition whereas the CBR value increases up to 9.7% for the case of 15% cement content. It is observed from the freezing and thawing tests, the strength of fly ash stabilized peat-reinforced fiber is decreased by 50%. Whereas the cement-stabilized peat is reducing its strength by 30%. Therefore, 15% of cement can be replaced with 12% of fly ash and 1% of nylon fiber together to make the stabilization effective in normal conditions, but not durable for weathering actions compared to cement-treated peat. The pavement thickness is evaluated from CBR value and observed that the stabilized peat-reinforced fiber significantly affects the thickness of the pavement. [ABSTRACT FROM AUTHOR]

This article presents the results of research on the use of a new granular organomineral fertilizer for growing plants of half-highbush cultivars of the lowbush blueberry (Vaccinium angustifolium Ait.). The purpose of the research is studying the effect of a new granular organomineral fertilizer on the agrobiological characteristics of V. angustifolium plants on a peatland in the conditions of the north of the European part of Russia. The developed composition of organomineral fertilizer (NPK 8:8:8, Fe 0.5%, Zn 0.2%, Cu 0.4%) differs from existing fertilizers in a more balanced ratio of micro- and macroelements and the content of vermicompost containing spore forms of bacteria Bacillus subtilis H-13, B. mucilaginosus, and Azotobacter chroococcum. The use of a new organomineral fertilizer on high-moor peat (pH 2.9) contributed to the highest yield of V. angustifolium fruits (190.2 g/bush), which is 1.2 times more than other mineral fertilizers (NPK, etc.). The best morphophysiological indicators of V. angustifolium plants (leaf area, total and working surface of the roots, root weight) when using the developed organomineral fertilizer were noted in September. An increase of 1.2–1.3 times in the collection of dry matter and sugars in fruits was revealed, compared with other fertilizer options, while the vitamin C content practically did not change. New organomineral fertilizer contributes to the optimal supply of the necessary micro- and macroelements throughout the growing season and increases the productivity of V. angustifolium plants when growing depleted peat deposits in the natural and climatic conditions of the European part of Russia. [ABSTRACT FROM AUTHOR]

The area of land dedicated to growing maize for bioenergy in the United Kingdom is rapidly expanding. To understand how maize production influences soil carbon (C) dynamics, and whether this is influenced by soil type, we measured net ecosystem exchange (NEE) using the eddy covariance technique over the 2021 growing season. We combined the NEE data with C imports and exports to calculate the net ecosystem productivity (NEP) of two maize crops grown for bioenergy in the United Kingdom, one site on mineral soil and the other on lowland agricultural peat. Maize was similarly productive at both sites—gross primary productivity was 1107 g C m−2 at the site with mineral soil and 1407 g C m−2 at the peat site. However, total ecosystem respiration was considerably higher from the peat site (1198 g C m−2) compared with the mineral soil site (678 g C m−2). After accounting for the removal of C in harvested biomass, both sites were net C sources, but C losses were over two times greater from the peat site (NEP = 290 g C m−2) than the mineral site (NEP = 136 g C m−2). While annual crops may be needed to produce bioenergy in the short term, growing maize for bioenergy in the United Kingdom does not appear to be a viable option for C sequestration over the long term, as it leads to high carbon losses from agroecosystems, especially those on organic soils. Instead, growing perennial bioenergy crops on mineral soils with a low organic C content is a more appropriate option. [ABSTRACT FROM AUTHOR]

The nickel hyperaccumulator Bornmuellera tymphaea has been evaluated for use in agromining in Greece with very promising results. This study examines propagation of this species based on cuttings, which provides rapid multiplication and clonal propagation of genotypes with useful genetic traits and offers obvious advantages over propagation by seed. Apical cuttings, 10 cm long, obtained from plants in the field, were propagated on mist benches under greenhouse conditions. Four treatments based on the rooting medium were evaluated: (a) perlite, (b) perlite + peat 1:1 (v/v), (c) ultramafic soil, and (d) ultramafic soil + perlite 1:1 (v/v). Completely randomized blocks were used in a 4 × 2 factorial design, using 4 different propagation rooting media and 2 levels of auxins (with or without the use of indole‐3‐butyric acid [IBA]), with 3 replicates of 28 cuttings. The response to perlite medium was best in terms of rooting: 75% without IBA and 71.33% with IBA, and the dry weight of roots was 0.18 g and of shoots 0.34 g. Perlite + peat 1:1 (v/v) medium also resulted in rooting in more than 55% of cuttings whereas cuttings grown in ultramafic soil showed very low rooting (<27%). Based on the findings, B. tymphaea has an aptitude for vegetative propagation by cuttings with survival values and rooting greater than 70%. Perlite combined with the application of auxin (ΙΒΑ) is recommended. [ABSTRACT FROM AUTHOR]

Humic substances are a type of biostimulant used in greenhouse production to promote plant growth and health. Our goal was to evaluate the effect of three commercially available biostimulants containing humic and/or fulvic acids (HumaPro, FulviPro, and Micromate) on the performance and tissue nutrient concentration of Solanum lycopersicum L. 'Bush Beefsteak' grown in a peat-based substrate. We conducted four experiments testing application rate and fertility level (50 and 100 mg⋅L–1 N) (Exp. 1), application rate and frequency (Exp. 2), direct Micromate incorporation into the substrate (Exp. 3), and FulviPro application method (drench vs. foliar spray) (Exp. 4). Plants were fertilized with 20N-1.3P-15.7K. Experiments 2, 3, and 4 were conducted under low fertility (50 mg⋅L–1 N). Micromate promoted growth when applied as a weekly drench at 40 g·L−1 or when incorporated into the substrate (20 g in 1 L of the substrate). Micromate-treated plants showed high P, S, and Si in the shoot and root tissues. FulviPro showed a negative effect when applied as a drench at higher rates, but foliar application increased greenness (Green Leaf Index). The negative effects of FulviPro might be due to the over-accumulation of Fe and Mn when applied as a drench. [ABSTRACT FROM AUTHOR]

This study presents a method that could be used to assess the in‐situ saturated vertical hydraulic conductivity of deeper and more decomposed peat layers. Deeper peat layers may exhibit very low permeability comparable to clayey sediments, where measurements and sediment sample collection are very difficult. More traditional measurement methods, such as slug‐tests and permeameter tests, have proven difficult to carry out in these conditions, necessitating an alternative method. For surpassing these possible constraints, this paper introduces a field method to quantify vertical hydraulic diffusivity, capitalizing on naturally occurring hydraulic pressure fluctuations measured with buried pressure sensors. The determined diffusivity values are used to calculate vertical hydraulic conductivity of peat using separately measured compressibility and specific storage values. Our research demonstrates the feasibility of using this method to evaluate vertical hydraulic diffusivity in lower peat layers. Calculated diffusivity values, combined with peat compressibility measurements, yield reasonable estimates of vertical hydraulic conductivity for dense fen peat comparable with more widely used in‐situ and laboratory methods. It also shows potential for vertical hydraulic characteristics parametrization in the upper less decomposed and compacted peat layers; however, further research is needed to understand the method's limitations in such conditions. Our approach provides a potential method for measuring in‐situ vertical hydraulic properties of less accessible peat layers, often overlooked, while also providing a way to surpass the scale‐dependency constraints inherent in peatlands' heterogeneous structure. Such information is necessary when studying the hydraulic interactions between groundwater aquifers and peatlands. [ABSTRACT FROM AUTHOR]

Specific yield affects how much the water table rises and falls in response to rainfall, to evaporation and to seepage gains and losses. It also affects the aeration of the soil above the water table. Although widely measured in peat soils, the effect of wetting history on its value has not been investigated. Specific yield has been estimated in many studies by cutting peat cores into layers, and measuring how much water drains from the individual layers after they have been wetted. Specific yield, however, is a phenomenon of the soil profile and not subsections, so this method may not provide a reliable estimate of its value. Few studies have reported on the effect of botanical composition on specific yield, or at least have not controlled for the effect by keeping other peat properties like degree of humification constant. We addressed these questions by measuring specific yield in intact cores of peat in a series of laboratory experiments. Two common but contrasting types of Sphagnum peat were investigated that had similar degrees of humification: Sphagnum medium peat and Sphagnum pulchrum peat. We found that specific yield was highly variable, ranging between 0.16 and 0.62. Specific yield was not affected by wetting history, but was significantly different between the peat types, being on average 0.21 higher in the S. pulchrum cores. Specific yield did not vary with depth in the S. medium cores but declined linearly with depth at a rate of 0.018 per cm in the Sphagnum pulchrum cores. Finally, we found that drainage from the peat profile above the zone through which the water table falls is an important component of specific yield, contributing more than 66%–91% of its value in the S. pulchrum peat. Our results show that wetting history probably does not need to be accounted for when estimating specific yield, although further work on this potential effect is recommended. Our work highlights the importance of measuring specific yield using intact cores (field methods may also be appropriate) and suggests that many previous peatland studies may have underestimated its value. [ABSTRACT FROM AUTHOR]

Cryptotephras in peat and sediment samples are traditionally separated for geochemical characterization using chemical or density floatation techniques following initial tephra identification and shard counting through analysis of ashed residue via light microscopy. However, these practices can be time consuming, subject to practitioner experience and material type, with a potential for sample loss. We present an alternative approach to identify cryptotephra in peat and sedimentary samples, where ashed material is mounted directly in epoxy resin and analysed through back‐scattered electron (BSE) imaging via scanning electron microscopy–energy dispersive X‐ray spectroscopy (SEM‐EDX). Semi‐quantitative, unsupervised chemical maps of epoxy mounts are created within 120 min using 'Feature Analysis' on AZtec software by Oxford Instruments. These maps locate grains of higher atomic mass and categorize phases based on geochemistry. We create a tephra identification method using an ombrotrophic peat sample doped with bimodal Vedde Ash, where recovery of the known tephra proportion in wet peat is 96%. We also propose an automated alternative to optical shard counting, whereby tephra counts identified via Feature Analysis can be ratioed to total grain counts acquired through ImageJ software and extrapolated to the inorganic fraction in wet peat. We apply the method to a minerotrophic peat from Brackloon Wood, Mayo, Ireland, where the Laki ad 1783–84 cryptotephra is successfully identified. [ABSTRACT FROM AUTHOR]

Emergent marsh and open water have been identified as alternate stable states in tidal marshes with large, relative differences in hydrogeomorphic conditions. In the Florida coastal Everglades, concern has been raised regarding the loss of non-tidal, coastal peat marsh via dieback of emergent vegetation and peat collapse. To aid in the identification of alternate stable states, our objective was to characterize the variability of hydrogeomorphic and biologic conditions using a field survey and long-term monitoring of hydrologic and geomorphic conditions across a range of vegetated (emergent, submerged) and unvegetated (open water) communities, which we refer to as "ecosystem states," in a non-tidal, brackish peat marsh of the coastal Everglades. Results show (1) linear relationships among field-surveyed geomorphic, hydrologic, and biologic variables, with a 35-cm mean difference in soil surface elevation between emergent and open water states, (2) an overall decline in soil elevation in the submerged state that was related to cumulative dry days, and (3) a 2× increase in porewater salinity during the dry season in the emergent state that was also related to the number of dry days. Coupled with findings from previous experiments, we propose a conceptual model that describes how seasonal hydrologic variability may lead to ecosystem state transitions between emergent and open water alternate states. Since vegetative states are only moderately salt tolerant, as sea-level rise pushes the saltwater front inland, the importance of continued progress on Everglades restoration projects, with an aim to increase the volume of freshwater being delivered to coastal wetlands, is the primary management intervention available to mitigate salinization and slow ecosystem state shifts in non-tidal, brackish peat marshes. [ABSTRACT FROM AUTHOR]

The aim of the presented study was to evaluate an integrated, direct procedure for the synthesis of humic‐silica composites (HSiC) by the isolation of humic substances (HS) from peat and lignite by the use of sodium silicate solution as an extractant. The obtained materials, because of the presence of humic functional groups, may potentially be used for removing contaminants from aqueous solutions. The quantitative assessment was based on experiments designed according to the Box‐Behnken plan. The statistical analysis of the results allowed to determine the optimal conditions of the process tested, for which the isolation efficiency of humic substances (HS) was greater than 50 % for both raw materials. This made it possible to synthesize humic silica composites with a high content of HS, which have been qualitatively evaluated. This step was focused on the analysis of the humic structure using elemental analysis, spectroscopic methods, and differential thermal analysis coupled with thermogravimetry. On the basis of them, the presence of structures characteristic for HS in the HSiC tested was observed. Moreover, the results of the thermal analysis pointed to the higher thermal stability of the synthesized compounds, compared to the HS isolated with the use of a traditional extractant. [ABSTRACT FROM AUTHOR]

As a typical biodegradable material, poly(lactic acid) (PLA) has great development potential in fields such as packaging, textiles and biomedical applications due to its high modulus and strength as well as excellent biocompatibility. However, the inherent brittleness and poor toughness of PLA significantly limit its widespread application. In this study, a biodegradable aliphatic–aromatic copolyester called poly(ethylene adipate-co-terephthalate) (PEAT) was synthesized using the industrially well-established direct esterification method. PEAT demonstrated excellent flexibility and extremely high fracture elongation. Its fracture elongation exceeded 900%, making it a highly ductile material with exceptional toughness. Given the complementary nature of PLA and PEAT, blending PLA with PEAT becomes a natural choice for improving the performance of PLA. The influence of the addition of PEAT on the mechanical properties, thermal performance, crystallization, phase morphology and rheological behavior of the blends was thoroughly investigated. With the addition of PEAT, the fracture mode changed from brittle fracture of the neat PLA to ductile fracture of the blends as illustrated by tensile test. The best toughening effect on PLA was achieved at a PEAT content of 30 wt%, with the elongation at break increasing from 6.7% for neat PLA to 359% for the binary blend, an improvement of 53 times. Additionally, the impact strength also increased from 4.4 kJ/m2 to 10.5 kJ/m2, an increase of 138%. DSC revealed that PEAT had a certain influence on the crystallization behavior of PLA. SEM showed that the PEAT toughening mechanism was primarily attributed to a shear yielding mechanism triggered by debonding cavitation. [ABSTRACT FROM AUTHOR]

In this paper, the use of vacuum consolidation to improve soft ground and increase its undrained shear strength (Su) is discussed. Since peat and organic clay have very low Su values, the construction of embankments and structures on these soils often cause ground failure. For the trial embankment conducted in this research project, soft ground composed of peat, organic clay and clay was improved by using vacuum consolidation, resulting in a significant increase in Su values, and an embankment 10.7 m high could be constructed on the improved ground without causing ground failure. It was demonstrated that the increased Su was the result of synergy of the relatively high normalised strength (Su/σ′v, where σ′v is the effective overburden stress) of peat and organic clay, and the unique loading mechanism of vacuum consolidation. It was also demonstrated that in the case of a relatively narrow embankment (e.g. road embankment and river levee), the effect of isotropic consolidation also contributes to increase the stability of the vacuum consolidated peaty ground. It was also found that if the (Su/σ′v)NC of the original ground and the overconsolidation ratio are known, the (Su/σ′v)OC of the given ground overconsolidated by vacuum consolidation can be predicted. [ABSTRACT FROM AUTHOR]

Degraded peat has a high potential for use in agricultural production, especially food crops. The water table, which impacts the production of greenhouse gases (GHGs), is the main problem concerning peat utilization. The study aimed to determine the production of greenhouse gases at various peat water levels. The study was conducted in a laboratory setting utilizing the soil column of undisturbed peat soil. The factorial experiment was arranged in randomized block design, with three replicates, with the first factor was peat cropping use: Maize (Zea mays L.), pineapple (Ananas comosus (L.) Merr.), and scrubs. The second factor was water level (0, 10, 20, 30 cm depth). Variables measured were GHG flux (CO2 and CH4), pH, redox potential, total C content, and ash content. The peat cropping use interacted significantly with the peat water level on the potential for CH4 and CO2 production and the value of global warming potential. Water table depth significantly increased CO2 flux and global warming potential (GWP) in all three peat cropping uses. The lowest GWP at a 0 cm peat water level was 944 (pineapple use), 961 (maize use), and 1097 mg CO2e m-2 d-1 (scrub use). Peat for pineapple cultivation produces the lowest CO2 production and GWP compared to maize cultivation and scrubs. The negative relationship between redox potential and GWP is significant in peat for scrub. The relationship between pH and GWP is significant in peat for pineapple and scrub. [ABSTRACT FROM AUTHOR]

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Copyright of Environmental & Social Management Journal / Revista de Gestão Social e Ambiental is the property of Environmental & Social Management Journal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Flammable vegetation in Tasmania, Australia often grows on organic soils that can burn if sufficiently dry. Aims: To develop an approach to identify a safe window for prescribed burning of vegetation on Tasmanian organic soils, when vegetation is dry enough to be combustible, yet organic soils are unlikely to burn. Methods: We compiled a dataset of when organic soils did and did not burn when exposed to vegetation fires. Focussing on moorland, we used binomial modelling to estimate the probability of organic soil burning in relation to soil dryness index (SDI) computed from climate data. Vegetation combustibility was inferred from fuel moisture content estimated from climate data and records of area burnt. Key results: Risk of soil fire varied with vegetation. In moorland, modelling predicted a 17% risk when SDI was 10, a conservative estimate because our dataset was biased towards positive records of soil fire. Using an SDI threshold of 10, the average annual number of 'safe combustible' days varied across Tasmania from 26 to 53. Conclusions: This approach can be used to refine safe burning guidelines on organic soil. Implications: This approach, when applied to an improved dataset, will assist fire management on organic soils. We propose a method to identify the climate window when prescribed burning in Tasmania, Australia is unlikely to lead to organic soil combustion, using observations of when organic soil fires occurred, and vegetation is dry enough to burn. [ABSTRACT FROM AUTHOR]