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Bio-based carbon dioxide removal encompasses a range of (1) natural sink enhancement concepts in agriculture and on organic soils including peatlands, and in forestry, (2) bio-based building materials, and (3) bioenergy production with CO2 capture and storage (BECCS). A common database on these concepts is crucial for their consideration in strategies and implementation. In this study, we analyse standardised factsheets on these concepts. We find different dynamics of deployment until 2045: for CO2 removal rates from the atmosphere, natural sink enhancement concepts are characterised by gradually increasing rates, followed by a saturation and potentially a decrease after few decades; forest-related measures ramp up slowly and for construction projects and bioenergy plants, annually constant removal rates are assumed during operation which drop to zero afterwards. The expenses for removing 1 t CO2 from the atmosphere were found to be between 8 and 520 € t CO2−1, which arises from high divergence both in capital and operational expenditures among the concepts. This high variability of expenses seems to suggest the more cost-effective concepts should be implemented first. However, aspects from economics, resource base and environmental impacts to social and political implications for Germany need to be considered for developing implementation strategies. All concepts investigated could be deployed on scales to significantly contribute to the German climate neutrality target. [ABSTRACT FROM AUTHOR]

Soil classification methods currently rely on soil borings or cone/piezocone penetrometer tests (CPT/CPTu). Literature provides several methods that classify soils based on two parameters (typically tip resistance and friction sleeve/porewater pressure) obtained from CPTu data, defining a soil behavior type. However, these methods face challenges in reliably classifying certain soils, such as organic soils. Robust and complex analyses are required to classify organic soils accurately. In this study, a random forest (RF) based method is developed to predict the presence and depth of organic soils. The RF model utilized features from CPTu soundings including tip resistance, sleeve friction, and pore pressure. The true location of organic soils, derived from index properties obtained from soil borings, served as the model's outputs. Unseen CPTu data was used to predict organic soils throughout the entire project alignment, serving as validation for the model. The model achieved an F1 score of 0.89. Settlement analyses were conducted to evaluate the practical implications of the model's predictions on levee fill costs. The RF-based model yielded settlement predictions that closely matched those obtained through boring predictions. In contrast, traditional classification methods underestimated settlements, resulting in lower estimates for levee fill costs. [ABSTRACT FROM AUTHOR]

Globally, annual emissions from managed organic soils accounts for up to 5% of all anthropogenic greenhouse gas (GHG) emissions. Climate-wise management and restoration of degraded organic soils could reduce GHG emissions quickly and at relatively low costs. The European Union (EU) Member States that have large areas of organic soils with high GHG emissions are Sweden, Finland, Germany, Ireland, Poland, Netherlands, and the Baltic countries. To meet the climate targets and objectives of the Paris Agreement the land-use sector is indispensable and mitigation policies targeting organic soils will be needed. The international regulatory framework is broad and quite unspecific. In contrast, the European Union has initiated binding regulation for the land-use sector through the EU Climate Law, the EU LULUCF regulation, and the proposed EU Nature Restoration Law. However, even this regulatory approach is not on track to deliver on its binding ambitions, indicating the need for more effective implementation measures also on organic soils in the EU and its member states. Furthermore, we argue that appropriate policy selection should consider current knowledge regarding the climate impacts of management options of organic soils. Lastly, we need more studies on GHG emissions, and standardized methods for GHG inventories, to resolve uncertainties surrounding the impacts of management to GHG emissions. Successful policy implementation requires more efforts but also improved scientific justification through continuous consideration of climate policy integrity and strengthening of the reliability of GHG inventories. [ABSTRACT FROM AUTHOR]

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.)

Tree lines in high latitudes and high altitudes are considered sentinels of global change. This manifests in accelerated encroachment of trees and shrubs and enhanced plant productivity, with currently unknown implications for the carbon balance of these biomes. Given the large soil organic carbon stocks in many tree line soils, we here wondered whether introducing highly productive plants would accelerate carbon cycling through rhizosphere priming effects and if certain soils would be more vulnerable to carbon loss from positive priming than others. To test this, organic and mineral soils were sampled above and below tree lines in the Swedish sub‐arctic and the Peruvian Andes. A greenhouse experiment was then performed to quantify plant‐induced changes in soil mineralisation rates (rhizosphere priming effect) and new C formation using natural abundance labelling and the C4‐species Cynodon dactylon. Several environmental, plant, soil and microbial parameter were monitored during the experiment to complement the observations on soil C cycling. Priming was predominantly positive at the beginning of the experiment, then systematically decreased in all soils during the plant growth season to be mostly negative at the end of the experiment at plant senescence. Independent of direction of priming, the magnitude of priming was always greater in organic than in corresponding mineral soils, which was best explained by the higher C contents of these soils. Integrated over the entire study period, the overall impact of priming (positive and negative) on the soil C balance was mostly negligible. Though net soil C loss was observed in organic soils from the sub‐arctic tundra in Sweden. Most notably, positive and negative priming effects were not mutually exclusive, rather omnipresent across ecosystems, depending on sampling time. The direction of priming seems to be fluctuating with plant productivity, rhizosphere carbon inputs and nutrient uptake. This highlights the need for integrative long‐term studies if we aim to understand priming effects at ecosystem scale and greenhouse and laboratory studies must be validated in situ to enable reliable ecological upscaling. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

The soil nematode communities in typical tundra soils of southern Chukotka have been analyzed. Five types of shrub and grass-shrub biotopes on Cryosols, Fluvisols, Histosols, Gleysols, and Cambisols were examined. The animals were extracted from the soil by the Baermann technique with subsequent determination of taxonomic diversity, total and relative abundance, and trophic groups. The highest number (7044 individuals/100 g of soil) and biomass (12.15 mg) of nematodes were found in the Histosol, and the minimum one (1000 individuals/100 g of soil; 1.96 mg) of nematodes in the Cryosol. Bacterivorous nematodes dominated in all soil types. The maximum percentage of bacterivorous nematodes (94%) were found in the Cambisol. The percentages of fungivorous nematodes in the studied soils ranged from 1 to 42%. Predatory and omnivorous nematodes were present in all soils except for the litter of the Cambisol. Their percentage ranged from 2 to 32%. Phytonematodes were few, their highest number was found in the Gleysol (18%). The nematode fauna of the soils under analysis differed significantly. The greatest diversity of nematodes was found in the peat horizon of the Fluvisol, and the smallest diversity of nematodes was recorded in the litter of the Cambisol. The values of Sigma Maturity Index ranged between 2 and 3. The Enrichment Index had low and moderate (1.40–41.02) values, and the Structure Index had high values (59.51–84.07). The Eudorylaimus and Plectus genera were eudominants in all soil types. The soil food webs formed in the biocenoses under consideration can be characterized as stable and structured except for the alder biocenosis. [ABSTRACT FROM AUTHOR]

Organic fertilizers, such as spent mushroom substrate (SMS), improve soil fertility, but studies comparing their effects on different agricultural soils are limited. In this study, the effects of standard, SMS and composed fertilizers on soils from conventional–integrated, organic and biodynamic farming were investigated. Soil samples were analyzed for microorganisms and the activity of β-glucosidase (β-GLU), β-1,4-N-acetylglucosaminidase (NAG), urease (URE), arylamidase (ARN), phosphatase (PHOS), acid phosphatase (PAC), alkaline phosphatase (PAH) and arylsulphatase (ARS). Biodynamic soil showed the highest microbial counts and enzyme activities, followed by organic and conventional soils. SMS significantly increased the number of microorganisms and enzyme activities, especially in biodynamic and organic soils. Seasonal variations affected all microorganisms and most enzymes in all soils, except NAG in conventional and organic soils. Biodynamic soil showed stable activity of enzymes and microorganisms throughout the year, indicating greater stability. This study concludes that soil microorganisms and enzyme activities respond differently to fertilization depending on the soil type, with SMS demonstrating beneficial effects in all tested soils. [ABSTRACT FROM AUTHOR]

Finnish agricultural soil conditions are regularly monitored both through national and European Union (EU)‐wide LUCAS Soil sampling. In this study, we compare temporal trends and variability in organic carbon content (OC), pH, phosphorus (P) and potassium (K) in 2009–2018 across the two datasets. The national monitoring programme encompasses more monitoring plots (620 vs. 134 in 2018), while LUCAS sampling is repeated more frequently and in addition to 2009 and 2018, it also includes data from 2015. The temporal variability in all examined indicators was substantially higher in the LUCAS dataset compared to the national monitoring data. In mineral soils, Spearman's rank correlation coefficient between element contents measured in 2009 and 2018 ranged between 0.82 and 0.94 in the national dataset, and between 0.52 and 0.67 in the LUCAS dataset. The results for organic soils mirrored those of mineral soils. The higher variability in the LUCAS dataset may be attributed to less precise geolocation of sampling plots and/or variations in the sampling protocol such as greater sampling depth and the use of a spade instead of a core auger. The greater temporal variability, coupled with a smaller number of sampling plots in the LUCAS dataset, resulted in lower statistical power making the detection of trends with a realistic magnitude more challenging. Further, in LUCAS data, the confidence intervals of trends were of the same magnitude, regardless of whether the data from the year 2015 was included or not. The national dataset was found to be sufficient for detecting nationwide trends in element contents. Our results indicate that refining sampling protocols and improving the location accuracy of sampling plots are more cost‐effective approaches to enhance the precision of temporal trend estimation than increasing the number of sampling plots. [ABSTRACT FROM AUTHOR]

The current study investigated the efficacy of a protein-based biopolymer called casein for the modification of the primary and secondary compressibility characteristics and ability to resist sustained moisture attack in organic soils. The dry mixing method was adopted for the tests with dosages of 0.5%, 1%, 2%, and 4% added as a percentage of the dry weight of the soil. Incremental consolidation tests indicated that the compressibility reduced with the inclusion of casein, leading to lower void ratios with an increase in consolidation pressure and casein concentration. The primary compression index (Cc) and secondary compression index (Cα) were reduced by 85% and 67%, respectively, for a 2% casein-soil mix at a consolidation pressure of 100 kPa. The compression ratio (Cα/Cc) for the 2% treated soil fell outside the range of 0.01, similar to organic soils with fibrous materials. The permeability was reduced with an increase in casein concentration up to 2% (10−10 m/s) but exhibited a rise at 4% due to the formation of effective flow paths by the formation of inter-aggregate voids. At extended curing periods, the fiber formations contributed to the strength gain in amended soils. However, the successive wetting and drying (w-d) cycles led to fiber detachment and reduced the resistance to moisture attack leading to collapse. The 2%-amended casein-soil mix proved to be most suitable in terms of reduced compressibility and sustained the highest number of w-d cycles. The findings from the current study support the inclusion of casein for short-term applications. The use of this novel material in the ground improvement industry will aid in waste management and recycling, and it can act as a replacement for unsustainable chemical stabilizers such as cement and lime. [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]

As soil microbial respiration is the major component of land CO2 emissions, differences in the functional dependence of respiration on soil moisture among Earth system models (ESMs) contributes significantly to the uncertainties in their projections. Using soil organic C (SOC) stocks and CO2 data from a boreal forest–mire ecotone in Finland and Bayesian data assimilation, we revised the original precipitation-based monotonic saturation dependency of the Yasso07 soil carbon model using the non-monotonic Ricker function based on soil volumetric water content. We fit the revised functional dependency of moisture to the observed microbial respiration and SOC stocks and compared its performance against the original Yasso07 model and the version used in the JSBACH land surface model with a reduction constant for decomposition rates in wetlands. The Yasso07 soil C model coupled with the calibrated unimodal Ricker moisture function with an optimum in well-drained soils accurately reconstructed observed SOC stocks and soil CO2 emissions and clearly outperformed previous model versions on paludified organo-mineral soils in forested peatlands and water-saturated organic soils in mires. The best estimate of the posterior moisture response of decomposition used both measurements of SOC stocks and CO2 data from the full range of moisture conditions (from dry and xeric to wet and water-saturated soils). We observed unbiased residuals of SOC and CO2 data modelled with the moisture optimum in well-drained soils, suggesting that this modified function accounts more precisely for the long-term SOC change dependency according to ecosystem properties as well as the contribution of short-term CO2 responses including extreme events. The optimum moisture for decomposition in boreal forests was found in well-drained soils instead of the mid-range between dry and water-saturated conditions as is commonly assumed among soil C and ESMs. Although the unimodal moisture modifier with an optimum in well-drained soils implicitly incorporates robust biogeochemical mechanisms of SOC accumulation and CO2 emissions, it needs further evaluation with large-scale data to determine if its use in land surface models will decrease the uncertainty in projections. [ABSTRACT FROM AUTHOR]

Copyright of Jurnal Tanah dan Sumberdaya Lahan is the property of Brawijaya University 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.)

Coastal wetlands experience acute and chronic disturbances which can affect rates of surface elevation change and vertical accretion of surface sediments. Disturbance can either amplify or impair the ability of wetlands to maintain their position within the tidal frame, with implications for their long-term persistence. Using an 8-year dataset collected from coupled surface elevation table-marker horizon (SET-MH) stations spanning riverine, bayside, and barrier island settings in the Apalachicola Bay region of north Florida, USA, this study investigated decadal-scale surface elevation change and vertical accretion rates to assess wetland vulnerability to acute (Hurricane Michael) and chronic (relative sea-level rise; RSLR) disturbance in different geomorphic settings. All sites had long-term accretion rates that exceeded rates of surface elevation change (pre-Michael), indicating that surface accretion was not a good indicator of changes in surface elevation for any of these coastal geomorphic settings. Hurricane Michael increased surface elevation change rates at bayside and riverine sites; barrier island sites consistently displayed the lowest surface elevation change rates, which did not differ between pre- and post-Michael periods. Accretion rates were greatest in the riverine sites, which were characterized by highly organic soils. Barrier island and bayside sites demonstrated elevation and accretion deficits relative to the rate of RSLR for Apalachicola Bay between 2010 and 2022, indicating high vulnerability of these sites to chronic increases in sea level. These estimates of marsh resilience relied exclusively on rates of vertical change and neglecting to account for lateral erosion failed to predict that each of the three barrier island sites experienced rapid loss of the seaward SET-MH stations during the observation period. These results provide evidence of different vertical change responses among coastal wetlands of three geomorphic settings exposed to hurricanes and RSLR in the same region and suggest different timelines for long-term persistence of these sites. [ABSTRACT FROM AUTHOR]

Efficient and sustainable food production is crucial in global agricultural development. Overuse of chemical fertilizers leads to soil acidification, destruction of soil properties, and harm to soil micro-organisms. Plant growth-promoting rhizobacteria (PGPR) have emerged as a solution, enhancing soil fertility and crop yields while reducing chemical fertilizer dependency and disease occurrence. In this study, Bacillus strains KHC2, KHH5, and KHH13, isolated from organic rice field soils in Taiwan, were identified through molecular techniques as B. velezensis (KHC2, KHH13) and B. amyloliquefaciens (KHH5). The strains exhibited various hydrolytic enzymes (including protease, cellulase, amylase, and lecithinase), with KHH13 showing the highest phosphate solubilization (2186.1 µg mL−1 day−1) and indole-3-acetic acid (IAA) production (63.067 ± 0.595 ppm mL−1). These properties indicate KHH13's potential as a bio-enhancer for plant growth. Therefore, we hypothesized that KHH13 can enhance plant growth and control soil-borne diseases. A greenhouse experiment demonstrated that KHH13, KHC2, and KHH5 effectively promoted the growth of red lettuce, with KHH13 showing superior efficacy. The study also found KHH13's treatment enhanced the growth of various vegetables, including tomato, cucumber, and red lettuce. In terms of disease control, KHH13 significantly reduced Fusarium wilt in cucumbers, as evidenced by the reduction in disease index from 74.33% to 41.67% after KHH13 treatment. The treatment group displayed better plant growth, including plant height and fresh weight, compared to the control group in the greenhouse experiment. Furthermore, oral and pulmonary acute toxicity analysis in rats showed no adverse effects on rat weight or mortality, indicating KHH13's safety for mammalian use. These findings suggest B. velezensis KHH13 as a safe, effective, and sustainable biological agent for enhancing vegetable growth and controlling soil-borne diseases, with potential applications in sustainable agriculture. [ABSTRACT FROM AUTHOR]

Fifty-five sugarcane genotypes from around the world were collected and evaluated for potential use as parental material in the USDA ARS Canal Point (CP) sugarcane breeding program in Florida, USA. The genotypes were planted in a trial with four check cultivars on organic soils with four replications, and data were collected for two years [i.e., plant cane (PC) and first ratoon (FR) crops] to assess sucrose-yield-related traits and the cane-yield-related traits in PC. Using a multivariate analysis, variation was observed in all cane—[i.e., stalk weight, stalk population and cane yield] and sugar-yield-related traits [i.e., Brix, Pol, sucrose content and commercial recoverable sucrose (CRS)]. The mean CRS content was greater in the FR crop than the PC crop. Significant variations were attributed to genotype (G), crop cycles (C) and G × C effects. Variations between crop cycles were highly significant for all sucrose yield components, which could complicate the downstream selection of genotypes for sucrose yield. Based on CRS content, genotypes could be grouped into six distinct clusters. Based on plant cane data, cane yield traits (stalk weight, stalk population and cane yield) were used to estimate the breeding values of parents. Of the 55 genotypes, 8 had significantly greater t-BLUP values for cane yield, along with CP 00-1101. Combined sucrose yield traits, (Brix, Pol and sucrose content) from the two crops were used to estimate the breeding values of parents. Of the 55 genotypes, 10 genotypes had significantly greater t-BLUP values for CRS, along with CP 00-1101, CP 96-1252 and CP 01-2390, and can be considered as elite parents in future breeding efforts. These results provide a foundation for the efficient integration of genetic diversity in developing commercial cultivars, with improved sucrose yields, into the CP sugarcane breeding program. [ABSTRACT FROM AUTHOR]

Integrated geo- and environmental monitoring in mining represents a high-dimensional challenge (location, altitude/depth, time and sensors). This is challenging for experts but poses great problems for a multitude of participants and stakeholders in building up a complete process understanding. The Epe research cooperation aims to elucidate the ground movement at the Epe cavern storage facility with a public participation process. The research cooperation was founded by the city of Gronau, the citizens' initiative cavern field Epe, the company EFTAS, Münster, and the Research Center of Post-Mining at the Technische Hochschule Georg Agricola, Bochum. This research cooperation is the first in Germany to involve direct collaboration between science and the public. In the cavern field, which has been in operation since the 1970s, brine is extracted, and at the same time natural gas, crude oil and helium, as well as hydrogen in the future, are stored in the subsurface. The technical focus of this work was the development of a high-resolution spatiotemporal analysis of ground movements. The area is monitored annually by the mining company's mine surveyor. The complexity of the monitoring issue lies in the fact that the western part is a bog area and a former bog area. Furthermore, the soils in the eastern part are very humus-rich and show strong fluctuations in the groundwater and therefore complex hydraulic conditions. At the same time, there are few fixed scatterers or prominent points in the area that allow high-resolution spatiotemporal monitoring using simple radar interferometry methods. Therefore, the SBAS method (Small Baseline Subset), which is based on an aerial method, was used to analyze the radar interferometric datasets. Using an SBAS analysis, it was possible to evaluate a time series of 760 scenes over the period from 2015 to 2023. The results were integrated with the mine survey maps on the ground movement and other open geodata on the surface, the soil layers and the overburden. The results show complex forms of ground movement. The main influence is that of mining. Nevertheless, the influence of organic soils with drying out due to drought years and uplift in wet years is great. Thus, in dry years, ground subsidence accelerates, and in wet years, ground subsidence not only slows down but in some cases also causes uplift. This complexity of ground movements and the necessary understanding of the processes involved has been communicated to the interested public at several public information events as part of the research cooperation. In this way, an understanding of the mining process was built up, and transparency was created in the subsurface use, also as a part of the energy transition. In technical terms, the research cooperation also provides a workflow for developing the annual mine survey maps into an integrated geo- and environmental monitoring system with the development of a transparent participatory geomonitoring process to provide resilience management to a mining location. [ABSTRACT FROM AUTHOR]

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]

This article discusses the use of spatial and temporal visualization techniques to understand the production and transport of dissolved organic carbon (DOC) in a high-elevation Andean catchment. The authors introduce a new model called STARR-DOC, which simulates the dynamics of DOC alongside water movement. The study focuses on the Zhurucay catchment and provides visualizations of water movement and DOC production in different soil types. The findings suggest that the production of DOC is influenced by soil water content, with the valley bottom areas exhibiting faster response times compared to the hillslopes. The visualization helps to identify areas within the catchment that have higher or lower DOC production and transport under different meteorological conditions. [Extracted from the article]

Disappearance of lakes is one of the most dangerous processes affecting the entire natural environment, including soil. This phenomenon is considered natural, resulting from climate change, however in recent decades, a significant acceleration of this process has been observed due to the direct impact of human activity. In areas directly adjacent to lakes, organic soils usually predominate. Unfortunately, wetlands are increasingly being drained and used for agricultural purposes. Under such circumstances, changes in the physical and chemical properties of these soils are often irreversible, causing their degradation. As an effect of increased mineralization, a number of typical modifications occur in soils, such as carbon loss, increased degree of peat decomposition, and changes in soil structure. Long-term dehydration has led to muck formation. Additionally, lowering of lake water uncovers previously flooded areas and increases the intensity of soil-forming processes. However, the presence of the Subaquatic qualifier in the World Reference Base for Soil Resources (WRB) suggests that sediments in shallow water bodies no more than 200 cm deep can also be classified as soils. The progressive disappearance of lakes observed all over the world is therefore a process affecting not only the reduction of water bodies, but also changes in the properties and typology of soils and vegetation cover. [ABSTRACT FROM AUTHOR]

'CP 15‐2516' (Reg. no. CV‐215, PI 703029) sugarcane cultivar, a complex hybrid of Saccharum spp., was developed jointly by USDA‐ARS, the University of Florida, and the Florida Sugar Cane League. CP 15‐2516 was released in June 2022 for commercial cultivation on the Florida organic (muck) soils due to its high cane and sucrose yields, commercial recoverable sucrose (CRS), and economic index (EI). CP 15‐2516 originated from CPX13‐1630, a cross between a female parent (CP 95‐1039) and a male parent ('CP 06‐2400'). CP 15‐2516 is resistant to brown rust, orange rust, and Sugarcane mosaic virus strain E. CP 15‐2516 harbors the Bru1 marker associated with brown rust resistance. CP 15‐2516 is moderately resistant to leaf scald and ratoon stunt disease, smut, and yellow leaf. Based on the results of three harvest cycles over five locations in Stage 4 on muck soils, cane and sucrose yields of CP 15‐2516 were 10.48% (181.31 Mg ha−1) and 11.49% (18.62 Mg ha−1) respectively, higher (P <.05) than those of the reference cultivar 'CP 96‐1252'. Compared with CP 96‐1252, the EI of CP 15‐2516 was significantly (P <.05) higher by 15% (3233 ha−1). The mean cane fiber content of CP 15‐2516 was 138.7 kg Mg−1 and was 1% to 8% higher than the reference cultivars ('CP 00‐1101', CP 96‐1252, and 'CPCL 05‐1201'). CP 15‐2516 flowers intermittently during January in Florida's climate. CP 15‐2516 has a better freeze tolerance than commercial reference cultivars CP 00‐1101 and CP 96‐1252. CP 15‐2516 is expected to positively contribute to the profitability and sustainability of the Florida sugarcane industry. Core Ideas: CP 15‐2516 sugarcane cultivar was released for commercial production on organic soils in Florida.Sucrose and cane yields of CP 15‐2516 were equivalent to or higher than those of reference cultivars.CP 15‐2516 was resistant and moderately resistant to economically significant diseases.CP 15‐2516 showed better cold tolerance than reference cultivars. [ABSTRACT FROM AUTHOR]

'CP 13‐1954' (Reg. no. CV‐218, PI 704104) sugarcane (Saccharum spp. hybrid) was developed through cooperative research conducted by the USDA–ARS, the University of Florida, and the Florida Sugar Cane League, Inc., and released to growers for organic (muck) soils in Florida in June 2020. The parentage of CP 13‐1954 is 'CP 85‐1491' × Poly 09‐24. Based on the results of three crops (plant cane, first ratoon, and second ratoon) in field trials conducted at five locations, CP 13‐1954 had higher cane yield (16.2%), sucrose yield (15.6%), and economic index (29.7%) at P <.05 compared with the reference cultivar, 'CP 96‐1252'. CP 13‐1954 stalks are usually taller than the reference cultivar, 'CP 00‐1101', with small‐to‐medium diameter, and exhibits resistance to ratoon stunting disease, Sugarcane mosaic virus strain E, brown rust, orange rust, and smut and moderate resistance to leaf scald on muck soils in Florida. CP 13‐1954 has Bru1 locus that provides resistance against brown rust. CP 13‐1954 showed moderate cold tolerance among all the tested cultivars. Core Ideas: CP 13‐1954 is a new sugarcane cultivar released for organic soils in Florida.CP 13‐1954 yields higher than commercial checks in organic soils in Florida.CP 13‐1954 is resistant to most of the common sugarcane diseases in Florida.CP 13‐1954 has moderate level of freeze tolerance. [ABSTRACT FROM AUTHOR]

Salinity control, nutrient additions, and sediment supply were directly or indirectly the rationale for a $220 million coastal wetland restoration project (Davis Pond River Diversion) that began in 2002. We sampled Mississippi River water going in and out of the receiving basin from 1999 to 2018 to understand why wetland loss increased after it began. There was a reduction in inorganic sediments, nitrogen (N), and phosphorus (P) concentrations within the ponding area of 77%, 39% and 34%, respectively, which is similar to that in other wetlands. But the average sediment accumulation of 0.6 mm year−1 inadequately balances the present-day 5.6 mm year−1 sea level rise or the 7.9 ± 0.13 mm year−1 accretion rates in these organic soils. Nutrients added likely reduced live belowground biomass and soil strength, and increased decomposition of the organic matter necessary to sustain elevations. The eutrophication of the downstream aquatic system from the diversion, principally by P additions, increased Chl a concentrations to a category of 'poor' water quality. We conclude that this diversion, if continued, will be a negative influence on wetland area and will eutrophy the estuary. It is a case history example for understanding the potential effects arising from proposed river diversions. [ABSTRACT FROM AUTHOR]

Information on the capacity of organic soils to capture and store carbon in old‐growth forests in the hemiboreal forest zone is scarce and fragmented. However, fine‐root data can provide valuable insights into soil carbon fluxes. Thus, the aim of the current study was to provide estimates of the fine‐root biomass (FRB), fine‐root production (FRP), and fine‐root turnover (FRT) rate by tree species and other functional groups in old‐growth (stand age 131–179 years) forests on mesotrophic organic soils dominated by Scots pine (Pinus sylvestris L.), with and without the effects of forest drainage. The sequential soil coring method was used to estimate the FRB and FRP. The total FRB was significantly higher in the undrained sites (6.8 ± 0.3 t ha−1) than in the drained sites (3.97 ± 0.1 t ha−1). The FRB of Scots pine in the undrained forest was significantly higher (1.7 ± 0.1 t ha−1) than in the drained forest (0.5 ± 0.1 t ha−1), supporting an extensive foraging strategy. The significantly higher mean FRB of Norway spruce (Picea abies [L.] Karst.) (1.4 ± 0.1 t ha−1) in the drained sites than the undrained sites (0.7 ± 0.2 t ha−1) can be explained by there being a higher proportion of spruce in the stand compositions, thus a higher standing volume of this species and an increased FRB. The FRB of dwarf shrubs (2.43 ± 0.2 t ha−1) formed the largest part of the total FRB in the undrained sites and the second largest (1.16 ± 0.1 t ha−1), following Norway spruce, in the drained sites. The total FRP was similar between the undrained (2.05 ± 0.31 t ha−1 year−1) and drained (1.82 ± 0.26 t ha−1 year−1) stands. However, considerable variability in the FRP was observed between different sites of the same forest site type. The FRT rate of Scots pine was twice as high in the drained sites than the undrained sites, suggesting faster nutrient and carbon input into the drained soil compared with the undrained soil. Estimates of FRB, FRP, and FRT rates for different functional groups can be used in carbon‐cycle modeling and in further calculations to estimate the carbon budget (balance) in forests on organic soils. [ABSTRACT FROM AUTHOR]

The current N and P fertilization practices for vegetable crops grown in organic soils are inaccurate and and may potentially damage the environment. New fertilization models are needed. Machine learning (ML) methods can combine numerous features to predict crop response to N and P fertilization. Our objective was to evaluate machine learning predictions for marketable yields, N and P offtakes, and the N/P ratio of vegetable crops. We assembled 157 multi-environmental fertilizer trials on lettuce (Lactuca sativa), celery (Apium graveolens), onion (Allium cepa), and potato (Solanum tuberosum) and documented 22 easy-to-collect soil, managerial, and meteorological features. The random forest models returned moderate to substantial strength (R2 = 0.73–0.80). Soil and managerial features were the most important. There was no response to added P and null to moderate response to added N in independent universality tests. The N and P offtakes were most impacted by P-related features, indicating N–P interactions. The N/P mass ratios of harvested products were generally lower than 10, suggesting P excess that would trigger plant N acquisition and possibly alter soil N and C cycles through microbial processes. Crop response prediction by ML models and ex post N/P ratio diagnosis and N and P offtakes proved to be useful tools to guide N and P management decisions in organic soils. [ABSTRACT FROM AUTHOR]

This research aims to compare the methods of bulk density measurements in peat soils. The methods are ring sample, peat auger, and syringe. The research was conducted in peat soils in Pontianak City. The research was carried out from June to December 2023. Peat samples were the surface peat (0-10 cm). The samples were collected from five plots, and five replications. On average, the value of bulk density measured by the ring sample was 0.27 g cm-3, which is significantly different from bulk density values measured by the peat auger and syringe: 0.11 g cm-3 and 0.09 g cm-3, respectively. Bulk densities of peat auger and syringe are statistically indifferent. Soil compaction during sampling causes the ring sample's high bulk density value. Accordingly, carbon stock calculation based on ring sample bulk density is significantly higher than carbon stocks calculated by bulk densities of auger and syringe. The bulk density measurement with a peat auger took longer because a water displacement approach must measure the sample volume. Collecting bulk-density samples with a syringe is the easiest and fastest. The volume of the syringe sample is only 10 cm3, and the sample can be taken until the mineral substratum. The number of sample collected by syringe can be significantly increased at 5 cm sampling interval, or equals to 10 sub-samples per 50 cm peat core. Pearson linear correlations of these three methods are sufficiently strong.

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.

Cultivated peatland (Histosol) in Southern Québec (Canada) is a rapidly declining non‐renewable resource used to grow most Canadian lettuce (Lactuca sativa L., Asteraceae). Rolled‐rye (Secale cereale L., Poaceae) cover crop is one of the conservation practices proposed to reach a more sustainable lettuce production, but the overall impact on the agroecosystem remains poorly studied in Histosols. We assessed multiple effects of rolled‐rye cover crop on the trophic chain associated with the lettuce aphid, Nasonovia ribisnigri (Mosley) (Hemiptera: Aphididae), a major pest of lettuce. During one growing season and through two consecutive lettuce crops, we monitored in situ the impacts of rolled‐rye cover crop on insect fauna and lettuce quality. We used visual scouting and yellow pan traps to assess plant colonization by N. ribisnigri, its natural enemies, and alternative prey. Exclusion cage experiments were also conducted to measure aphid fitness and population growth. Under greenhouse conditions, following cover crop removal, we examined potential lingering effects of rye within the soil on lettuce plants and N. ribisnigri. In situ experiments showed that rolled‐rye cover crop has the potential to inhibit N. ribisnigri field colonization and recruit natural enemies and alternative prey in the first lettuce crop. Rye also reduced aphid fitness as well as lettuce foliar amino acid concentration and weight. For the second lettuce crop, an almost 50% reduction in N. ribisnigri abundance was observed with the use of rolled‐rye cover crop. In greenhouse experiments, no persistent effect of rye was observed on the quality of lettuce grown with soil collected under a cover crop, nor on the fitness of aphids inoculated on these lettuces. This study highlights the diversity of trophic effects rolled‐rye cover crop may have on lettuce production in Histosols and the potential of rolled‐rye cover crop as a cultural practice to reduce aphid populations. Mechanisms at play while underlining agronomic challenges regarding proper rye termination must be further explored to maintain high‐performing lettuce yields. [ABSTRACT FROM AUTHOR]

Numerous studies focus on investigating organic soils with high organic content. However, only a limited amount of literature discusses the properties and behaviour of low organic content soils. Sri Lankan organic soil is an excellent example of a low organic content soil, demonstrating different behaviour from highly organic fibrous soil. Scanning electron microscope (SEM) images of Sri Lankan organic soil were studied to determine the reasons for these observed variations. Sri Lankan organic soils were observed to consist of highly decomposed organic matter in an amorphous state with higher proportions of mineral matter. The microstructure characteristics observed through SEM images mostly explained the variation of properties and behaviour of the Sri Lankan organic soil in contrast to highly organic fibrous soil. Correlations were also derived between properties of Sri Lankan organic soil and compared with similar relationships derived from other geological conditions. While some correlations derived in this study closely follow the relationships for other organic soils with similar microstructure characteristics, the acidity of the deposit resulted in different behaviour of a few correlations. This study improves the current knowledge of the effect of microstructure characteristics on the properties and behaviour of Sri Lankan low-organic clayey soils, which otherwise primarily depend on theories for highly organic peaty soils. Furthermore, the correlations derived and validated for low organic soils can be utilized in any organic clay deposit with similar microstructure characteristics. [ABSTRACT FROM AUTHOR]

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Drained organic soils in agricultural land are considered significant contributors to total greenhouse gas (GHG) emissions, although the temporal and spatial variation of GHG emissions is high. Here, we present results of the study on soil-to-atmosphere fluxes of carbon dioxide (CO2), nitrous oxide (N2O) and methane (CH4) from drained organic (fen) soils in grassland. A two-year study (from July 2021 to June 2023) was conducted in three research sites in Latvia (Europe's hemiboreal zone). Soil total respiration (Rtot), CH4 and N2O fluxes were determined using a manual opaque chamber technique in combination with gas chromatography, while soil heterotrophic respiration (Rhet) was measured with a portable spectrometer. Among research sites, the thickness of the soil organic layer ranged from 10 to 70 cm and mean groundwater level ranged from 27 to 99 cm below the soil surface. Drained organic soil in all research sites was a net source of CO2 emissions (mean 3.48 ± 0.33 t CO2-C ha−1 yr−1). No evidence was obtained that the thickness of the soil organic layer (ranging from 10 to 70 cm) and OC stock in soil can be considered one of the main affecting factors of magnitude of net CO2 emissions from drained organic soil. Drained organic soil in grassland was mostly a source of N2O emissions (mean 2.39 ± 0.70 kg N2O-N ha−1 yr−1), while the soil both emitted and consumed atmospheric CH4 depending on the thickness of the soil organic layer (ranging from −3.26 ± 1.33 to 0.96 ± 0.10 kg CH4-C ha−1 yr−1). [ABSTRACT FROM AUTHOR]

Background: 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. New information: 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. [ABSTRACT FROM AUTHOR]

Purpose: A study was carried out to understand the carbon sequestration potential of the coastal acid sulfate soils of wetland agroecosystems Kari and Kayal of Kuttanad, Kerala. Methods: Soil profiles excavated in these lands were studied for their physico-chemical and morphological properties and classified according to USDA based soil taxonomy. Results: The soils were very deep with moderately deep (97 cm) and moderately shallow (75 cm) solum thickness and both the soils were acidic,sulfuric and/or sulfidic and saline.The BaCl2 acidity,exchangeable Al,total exchangeable bases and cation exchange capacity were higher in Kari soils.Both the soils recorded high sulfate S,which was higher in Kari soils.Based on the USDA soil taxonomy, Kari soils were classified to ferrihumic, euic, isohyperthermic, Typic Sulfohemists and Kayal soils to loamy, mixed, super-active, isohyperthermic, Salidic Sulfaquepts at the family level. Conclusion: The organic carbon stock was higher in the sub-surface layer (30-100 cm) which recorded 2769.63 and 645.45 Mgha− 1 in Kari and Kayal lands respectively. The soil carbon sequestration potential was higher in Kari soils and the highest rate of C sequestration was at the depth 30–60 cm(656.09 kgm− 3) and soil layer was proved to have the capacity to hold 20.40 TgC with a total of 58.86 TgC in 11,250 ha of Kari lands for a thickness of 150 cm, while Kayal soils recorded the maximum at the depth 60-90 cm (163.43 kgm− 3) with a capacity to hold 3.29 TgC with a total of 21.02 TgC in 13,000 ha of Kayal lands for a thickness of 150 cm in 13,000 ha of Kayal lands. [ABSTRACT FROM AUTHOR]

The model test investigations on the soft soils are usually carried out on samples prepared in the laboratory and assuming site conditions. However, such soils that are prepared in the laboratory only partially reflect the site conditions. Considering this gap in the literature, this study mainly focuses on the bearing capacity and settlement behavior of the undisturbed organic soil obtained by a novel block sampling technique. The disturbed organic soil prepared in the laboratory was investigated with large-scale model experiments for two different footing types (square and rectangular). Vane Shear testing (VST), Dynamic Cone Penetration (DCP) tests, and finite-element analysis (FEA) were performed. The average bearing capacity values of disturbed and undisturbed soil were 60.98 kPa–68.71 kPa and 108.18 kPa–110.89 kPa for square and strip footings, respectively. Bearing capacity reductions of up to 40% were determined on laboratory-prepared soils. The cone reached the required depth (450 mm) with three blows for disturbed soil, while it was reached with four blows for undisturbed soil. Likewise, the undrained shear strength obtained by the VST was determined as 22.16 kPa and 16.60 kPa for undisturbed and disturbed soils, respectively. Shear strength losses of up to 25% for disturbed soils were observed. The bearing capacity values obtained from FEA were comparable to those obtained with the model tests. It was concluded that the degree of degradation of organic soils in the laboratory significantly affects the bearing capacity of the soil. [ABSTRACT FROM AUTHOR]

Free radicals (FRs) are intermediate participants in the transformation process of soil organic matter, and free radical activity is a fundamental property of humic substances. The aim of this work was to conduct a comparative study of the paramagnetic properties of humic acids (HAs) isolated from Histosols by electron paramagnetic resonance (EPR) spectroscopy. The studied Histosols are found in permafrost peatlands in four natural geographic subzones of the European Arctic (from forest tundra to northern tundra). The results obtained showed that in anaerobic conditions on the peatlands in the tundra zone, the formation of semiquinone-type radicals occurs through the reduction of quinone fragments of HAs and leads to an increase in the concentration of paramagnetic centres within HAs. PCA analysis allowed us to reveal relationships between the properties of the initial raw peat samples, the molecular composition of the isolated HAs, and their paramagnetic parameters. It was found that FR localization occurs predominantly on aromatic fragments of lignin nature, which are confined to the low molecular weight fraction of HAs. The g-factor values of the EPR spectra of HAs indicate the presence of carbon- and oxygen-centred FRs in the HA structure, with a predominance of the latter. [ABSTRACT FROM AUTHOR]

The paper presents the methods of determining the characteristic value on the basis of the standards: PN-B-03020:1981, PN-EN 1997-1:2008, prEN 1997-1:2022-09 and Schneider formula. Determination of the characteristic value of the undrained shear strength τfu was carried out using statistical method on the basis of the prEN 1997-1:2022-09 standard and Schneider formula. The statistical calculations were based on the results of field vane tests carried out in organic subsoil of test embankment in Antoniny test site before loading and after the 2nd embankment stage. In order to determine the undrained shear strength τfu of organic soils from field vane tests, the measured values of shear strength τfv were corrected using the average values of correction factors µ = µ(lab) determined on the basis of triaxial compression, simple shear and triaxial extension tests. The analysis of the calculation results shows that with relatively numerous data sets, large values of the coefficient of variation Vx result in significantly lower characteristic values of τfu obtained according to prEN 1997-1:2022-09, compared to the values obtained according to the Schneider formula. In the case of few data sets, for which high values of the coefficient kn are obtained, with high values of the coefficient of variation Vx, the comparison of the values according to prEN 1997-1:2022-09 with the values obtained according to the Schneider formula shows the greatest differences. [ABSTRACT FROM AUTHOR]

Soil stabilization using additives is considered as one of the sustainable alternative techniques to deal with acute material shortages. Critically reviewing the contemporary works on soil stabilization would help practitioners and researchers to comprehend the merits and demerits of each stabilization method, influential parameters, and associated constraints. Furthermore, the critical analysis might aid the authorities to develop standard protocols about the use of various additives for soil stabilization, which would persuade the industry personnel to adopt sustainable practices. This paper presents a methodical review of the present soil stabilization methods under five key areas namely, underlying chemistry, the influential factors, performance indicators, economic and environmental aspects, and industrial perspectives. Findings of the review indicate that cement-based stabilizers perform well irrespective of soil type and curing conditions, on the contrary, lime-based stabilizers require appropriate temperature and pH for strength development. The degree of stabilization depends mainly on soil type, compaction level, and curing type and condition. Most of the soils treated with different additives exhibited a reduction in plasticity index, and maximum dry density against stabilizer dosage irrespective of soil type. The typical values of unconfined compressive strength and California bearing ratio of inorganic and organic soils except for peat, treated with a 5% dosage of all common types of stabilizers, fall in between 700 and 1,500 kPa and 30–60%, respectively. Cement and cementitious blends exhibited better cost-to-strength, energy-to-strength, and CO2 emission-to-strength ratios for soils with low plasticity whereas lime-blended stabilizers seemed effective for high-plastic soils. [ABSTRACT FROM AUTHOR]

Histosols cover about 8–10% of Lithuania's territory and most of this area is covered with nutrient-rich organic soils (Terric Histosols). Greenhouse gas (GHG) emissions from drained Histosols contribute more than 25% of emissions from the Land Use, Land Use Change and Forestry (LULUCF) sector. In this study, as the first step of examining the carbon dioxide (CO2) fluxes in these soils, total soil CO2 efflux and several environmental parameters (temperature of air and topsoil, soil chemical composition, soil moisture, and water table level) were measured in drained Terric Histosols under three native forest stands and perennial grasslands in the growing seasons of 2020 and 2021. The drained nutrient-rich organic soils differed in terms of concentrations of soil organic carbon and total nitrogen, as well as soil organic carbon and total nitrogen ratio. The highest rate of total soil CO2 efflux was found in the summer months. Overall, the rate was statistically significant and strongly correlated only with soil and air temperature. A trend emerged that total soil CO2 efflux was 30% higher in perennial grassland than in forested land. Additional work is still needed to estimate the net CO2 balance of these soils. [ABSTRACT FROM AUTHOR]

Copyright of Revista de Ciencias Agricolas is the property of University of Narino, Faculty of Agricultural Sciences 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.)

Arctic warming increases the degradation of permafrost soils but little is known about floodplain soils in the permafrost region. This study quantifies soil organic carbon (SOC) and soil nitrogen stocks, and the potential CH4 and CO2 production from seven cores in the active floodplains in the Lena River Delta, Russia. The soils were sandy but highly heterogeneous, containing deep, organic rich deposits with >60% SOC stored below 30 cm. The mean SOC stocks in the top 1 m were 12.9 ± 6.0 kg C m−2. Grain size analysis and radiocarbon ages indicated highly dynamic environments with sediment re‐working. Potential CH4 and CO2 production from active floodplains was assessed using a 1‐year incubation at 20°C under aerobic and anaerobic conditions. Cumulative aerobic CO2 production mineralized a mean 4.6 ± 2.8% of initial SOC. The mean cumulative aerobic:anaerobic C production ratio was 2.3 ± 0.9. Anaerobic CH4 production comprised 50 ± 9% of anaerobic C mineralization; rates were comparable or exceeded those for permafrost region organic soils. Potential C production from the incubations was correlated with total organic carbon and varied strongly over space (among cores) and depth (active layer vs. permafrost). This study provides valuable information on the carbon cycle dynamics from active floodplains in the Lena River Delta and highlights the key spatial variability, both among sites and with depth, and the need to include these dynamic permafrost environments in future estimates of the permafrost carbon‐climate feedback. Plain Language Summary: Floodplain soil development results from both geological processes, such as sediment erosion and deposition, and biological processes such as vegetation growth. In the Arctic, these processes interact with permafrost to form deep soils, but the carbon stocks and potential decomposition and greenhouse gas emissions from Arctic floodplain soils are relatively unknown. In this study, we investigate carbon stocks and potential decomposition from Arctic floodplain soils to depths of 1 m from a large river delta in Siberia. We show that it is difficult to predict what soil types, carbon stocks, and potential decomposition and emissions are found beneath the surface because the sites vary strongly despite having similar vegetation at the surface owing to the depositional processes that occur in floodplains. Key Points: Active floodplains in the Lena River Delta contain sandy permafrost soils with strongly varying C stocks despite similar surface vegetationCarbon stocks in active floodplains were relatively low but only 40% was found in surface soils indicating the importance of deep soilsPotential carbon loss from incubations showed average aerobic carbon production but very active anaerobic carbon and methane production [ABSTRACT FROM AUTHOR]

Peatland degradation might affect peatland functions. Sustainable agriculture practice, i.e., nutrient management, is one of the efforts that could be made to delay the degradation. Therefore, this research aimed to identify the best nutrient management practice for shallot production in degraded peatlands. A split-plot experimental design was performed in a greenhouse environment, with cultivars (Sembrani and Trisula) as the main plot and eleven combinations of NPK fertilizer as the subplot. All treatments received 4.4 t ha-1 dolomite to increase the soil pH. Results showed that Sembrani produced a higher bulb yield than Trisula. Trisula was sensitive to acidic soils and failed to yield a high bulb. The NPK recommended dose for Sembrani was 150 kg N ha-1, 100 kg P2O5 ha-1, and 100 kg K2O ha-1, producing 57.50 g plant-1 equal to 14.4 t ha-1 or 53% higher than the control (without NPK). Meanwhile, growing Trisula was not recommended for peatlands. [ABSTRACT FROM AUTHOR]

A dielectric model based on the refractive dielectric model of the mixture of thawed and frozen forest organic soils in the root zone for a frequency of 435 MHz has been developed. The model is created on the basis of dielectric measurements of four soils whose organic matter content varies in the range from 15 to 31%. The dielectric measurements are carried out in the range of the gravimetric moisture from 0 to 0.6 g/g and temperature range from –30 to 25°C. The coefficient of determination (R2) between values calculated by the model and measured values of the real (ε') and imaginary (ε'') parts of complex dielectric permittivity is 0.97. The normalized root-mean-square error is 16 and 21% for the real and imaginary parts of the complex dielectric permittivity, respectively. This dielectric model may be applied in remote sensing algorithms when retrieving the value of forest soil moisture in the root zone from radar and radiometric data. [ABSTRACT FROM AUTHOR]