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... Methodologies based on ¹³C‐enrichment (E), ¹³C‐depletion (D) and ¹³C‐natural abundance (NA) to estimate the stability of biochar in soil were critically examined. The stability of ¹³C‐enriched biochar can be estimated by the quantitative recovery of excess ¹³C, either in the soil or in evolved CO₂. Both approaches have advantages and disadvantages. Recovery in the soil is a measure of both residua ...
... Digital soil mapping (DSM) approaches provide soil information by utilising the relationship between soil properties and environmental variables. Calibration of DSM models requires measurements that may often have substantial measurement errors which propagate to the DSM outputs and need to be accounted for. This study applied a geostatistical‐based DSM approach that incorporates measurement error ...
... Macroscopic models of soil organic matter (SOM) turnover have faced difficulties in reproducing SOM dynamics or in predicting the spatial distribution of carbon stocks. These models are based on a largely inadequate linear response of soil microorganisms to bulk concentrations of nutrients and it is clear that a new approach to SOM modelling is required. Introducing explicit microbial activity and ...
... There is increasing evidence that the accessibility of soil organic matter (SOM) to microbial decomposers is more important than chemical recalcitrance for regulating SOM stability. We show that the rapid reduction in SOM decomposition following the addition of sorptive mineral phases to soils in laboratory conditions leads to decreased accessibility of SOM to microbial decomposers due to the form ...
... Na⁺, K⁺, Cs⁺ and Ca²⁺ are common exogenous cations that could be introduced into soils either via long‐term tillage with inorganic fertilizers or the leakage of nuclear waste. However, the manner in which they co‐adsorb and compete with the intrinsic potassium ions in illite, the response of intrinsic potassium (K′⁺), as well as the underlying mechanisms of these interactions, remain unclear. Thes ...
... Combatting subsoil acidity is a challenge as the incorporation of lime in subsurface layers may not be economically feasible. The use of nitrate to facilitate plant excess anion uptake has shown the potential to increase soil pH. A column experiment was carried out to demonstrate this root‐induced alkalization in various depths in an acid soil with pH 4.28 (0.01 M CaCl₂). It consisted of two types ...
... Copper (Cu) is an essential element for plants and microorganisms and at larger concentrations a toxic pollutant. A number of factors controlling Cu dynamics have been reported, but information on quantitative relationships is scarce. We aimed to (i) quantitatively describe and predict soil Cu concentrations (CuAR) in aqua regia considering site‐specific effects and effects of pH, soil organic car ...
... Long‐term field experiments (LTEs) are invaluable in improving understanding of soil organic matter (SOM) turnover, as some of the involved processes have proceeded over centuries. Prediction of such slow carbon fluxes depends especially on the initialization of slow‐reacting model pools and requires monitoring for a very long time for evaluation. This study reports soil organic matter (SOM) model ...
... Increasing the diversity of crops grown in arable soils delivers multiple ecological functions. Whether mixtures of residues from different crops grown in polyculture contribute to microbial assimilation of carbon (C) to a greater extent than would be expected from applying individual residues is currently unknown. In this study, we used ¹³C isotope labelled cover crop residues (buckwheat, clover, ...
European Union; arid lands; biodiversity; climate; climate change; dry environmental conditions; ecotoxicology; food availability; food production; human nutrition; organic matter; pH; Europe
Abstract:
... Dryland soils provide different societal and environmental services, such as food supply and biodiversity support. In Europe, most of the dryland areas are devoted to agriculture. In the next decades, both European and worldwide drylands are expected to suffer with increased intensity due to the expected climate change‐derived rise in aridity. Many studies have focussed on aridity‐induced changes ...
... Methanotrophs contribute significantly to methane consumption in paddy ecosystems. Currently, the biogeographical distribution and regulation of methanotrophs in Chinese paddy soils remain poorly understood. Here, we investigated the activity, abundance and community structure of methanotrophs in paddy soils from different geographical regions and three climate zones across China, with a total of ...
... Reduced use of fossil energy by removing cereal straw for bioenergy potentially threatens soil organic carbon (SOC) storage. Straw incorporation plays a key role for SOC storage in cereal‐based cropping systems, but the use of cover crops (CCs) may compensate for straw removal. However, assessing the SOC sequestration potential of management changes requires field experiments with long continued t ...
... Glyphosate is the most widely used herbicide in Argentina. The strong sorption of glyphosate to the mineral fraction of the soil can be affected by environmental conditions and agricultural management, such as the application of fertilisers. This work aimed to study the effect of pH and the presence of inorganic phosphate on the affinity of glyphosate for nine different surface soils of Argentina. ...
... In the present paper, the authors attempt to explain the importance of pH in soil environment studies and show what mistakes to avoid when measuring pH and interpreting the results obtained. The tests conducted (i.e., extraction in aqua regia, buffer capacity determination, and the impact of acidification on the amount of heavy metals extracted from soils) demonstrated how soil pollution and buffe ...
... Humans influence desert ecosystem structure and function by transforming native vegetation into agricultural and non‐agricultural land. However, how different land uses in desert grasslands affect soil phosphorus (P) fractions with varying lability by creating distinct soil physicochemical and microbial properties remains poorly understood. To address this question, a field study was conducted in ...
age of soil; allophane; aluminum; imogolite; soil organic carbon; soil profiles; volcanic soils
Abstract:
... The objective of the present study was to investigate the formation, accumulation and potential role of charred plant fragment (CPF)–aluminium (Al) complexes in several buried A (Ab) horizons of a cumulative volcanic soil profile, focusing on CPFs, active Al components and soil age. Nineteen soil samples were collected from four buried humic horizons (2A–5A, from 7.3 cal ka BP to AD 1471), and the ...
Amanda M. Tadini; Ladislau Martin‐Neto; Aleksandar I. Goranov; Débora M. B. P. Milori; Alberto C. C. Bernardi; Patricia P. A. Oliveira; José R. M. Pezzopane; Luiz A. Colnago; Patrick G. Hatcher
... Soil organic matter (SOM) plays an essential role in agronomic systems and is of great importance to environmental sustainability and carbon sequestration. This study evaluates the accumulation of carbon in soils from integrated agricultural systems (S) that include crop (C), livestock (L), and forest (F) components (in different combinations: CLFS, LFS and CLS) and an undisturbed native forest (N ...
community structure; magnetism; soil; soil ecosystems; soil fertility
Abstract:
... Microbial morphology fundamentally constrains how species interact with their environment, and hence ultimately affects their niche. However, the methodology of functional microbes in the soil ecosystem is still poorly studied since it is difficult to capture and identify the active monospecific community from the complicated environment and enormous number of microbial species in soils. To compre ...
... Soil particle aggregation is closely related to soil quality and pollutant migration in the environment. Soil is a naturally complex system with multi‐components, including different organic and inorganic particles. However, current studies with respect to particle aggregation by dynamic light scattering (DLS) have centred on single‐component particles. Therefore, the application of DLS to mixture ...
Actinobacteria; Firmicutes; Nitrospirae; Zygomycota; fungi; grasslands; mountains; nitrate nitrogen; organic carbon; phosphorus; soil pH; species richness; surveys; temperature; total nitrogen
Abstract:
... Plants often show remarkable elevational distribution patterns in arid‐montane ecosystems. However, it is not clear if soil microbes follow elevational diversity patterns, even though they represent the majority of biodiversity and drive varieties of ecological processes. Here, we conducted a survey of fungal and bacterial communities across an elevational gradient from 2350 to 3850 m in a typical ...
biodiesel; byproducts; carbon; clay loam soils; financial economics; glycerol; loamy sand soils; microbial biomass; mineralization; nitrate nitrogen; nitrates; nitrogen; soil amendments; water quality; Midwestern United States
Abstract:
... Loss of nitrate‐nitrogen (NO₃⁻–N) from Midwestern U.S. agricultural fields can impair water quality and be an economic loss to farmers. Winter cover crops have shown promise as a remedy, but low adoption illustrates the need for alternatives. Here, we tested whether adding a carbon (C)‐rich soil amendment (i.e., crude glycerol, a biodiesel byproduct) can increase soil microbial biomass (MB) and pr ...
... Understanding the dynamics of decomposition and release of nutrients from plant residues of different covers, in association or succession, is essential to define more sustainable management strategies in tropical soils. The objective of this study was to estimate the decomposition rates and the release of nutrients during the decomposition of different crop residues with different chemical compos ...
... Soil structure and organic carbon are key factors that reflect soil quality in sustainable agricultural production. Many studies have concentrated on soil aeration under intensive anthropogenic agricultural practices, but the relationship between soil aggregate stability and soil organic carbon (SOC) functional groups is poorly understood, particularly in degraded greenhouse vegetable fields conve ...
Picea; biomass; carbon dioxide; forest litter; humus; mineral soils; mineralization; mor; mull; nitrogen; soil organic carbon; species diversity; temperate forests; topsoil; total nitrogen; trees; vesicular arbuscular mycorrhizae; Norway
Abstract:
... Temperate forest soils are often considered as an important sink for atmospheric carbon (C), thereby buffering anthropogenic CO₂ emissions. However, the effect of tree species composition on the magnitude of this sink is unclear. We resampled a tree species common garden experiment (six sites) a decade after initial sampling to evaluate whether forest floor (FF) and topsoil organic carbon (Cₒᵣg) a ...
... Microbial residues are essential for soil organic carbon (SOC) accumulation and stability. However, the interactive effects of cropping system and fertilisation on microbial residues and their contributions to SOC have not been addressed. Herein, we used amino sugars as tracers for microbial residues and analysed the dynamics of microbial residues in a 31‐year‐long experiment in a highland agroeco ...
... The effect of reaction between soil and phosphate on pH has not previously been explored or explained. We incubated samples of a soil with calcium carbonate to give a range of pHCaCl2 from 4.2 to 7.2, and then measured the change in pH when these samples were reacted with phosphate solutions. These solutions were at the same pH as the soil to which they were added. We also measured exchangeable ca ...
Bárbara Fuentes; Francisco Gómez; Catalina Valdez; Anael Videla; Juan Castro‐Severyn; Sergio Barahona; Roland Bol; Rodrigo Riquelme; Javier Quispe; Francisco Remonsellez
... Rare Pacific coast fog ecosystems are under threat from climate change and local factors. Although coastal fog is known to affect soil properties and microbial diversity, few studies on the Pacific coast have examined the specific microbiomes associated with these ecosystems. We evaluated the effects of coastal fog on the physicochemical, mineralogical, and microbiological properties of bare soils ...
Cambisols; climate; grasslands; manganese; microbial biomass; organic matter; phosphorus; redox potential; soil fertility; surface water; water content; water quality
Abstract:
... Flooding is known to mobilise soil phosphorus (P). However, it is still not clear how climate change‐driven extended periods of soil drying followed by flooding will affect soil‐P dynamics. We tested the hypothesis under laboratory conditions that soil antecedent conditions (moist/dry) determine the amount of P mobilised upon flooding. A series of controlled laboratory experiments were carried out ...
... The incorporation of straw into soil has been encouraged as an alternative straw‐disposal strategy to the on‐site burning that occurs in many paddy regions. However, this practice may lead to changes in the colloidal properties of soil clays that potentially intensify clay and nutrient losses. This study aimed to demonstrate the effect of engineered microsized straw powder on the colloidal propert ...
Betula pendula; Pinus pinaster; Podzols; Quercus robur; biomass; forest litter; forest management; irrigation; mineral soils; plant available water; primary productivity; rhizodeposition; soil depth; soil organic carbon; trees; water shortages; France
Abstract:
... Mixing tree species is a forest management strategy put forward to increase and stabilize primary productivity. Yet, little is known about soil organic carbon (SOC) storage in mixed species forests, particularly under water shortage. In this study, we used a tree diversity experiment in southwestern France to assess the interactive effects of water availability (via irrigation) and mixing tree spe ...
Salvia hispanica; compressibility; energy; mucilages; rhizosphere; root growth; sand; sandy soils; soil water; water content
Abstract:
... Mucilage released by plant roots affects hydrological and mechanical properties of the rhizosphere. The aim of this study was to disentangle the effects of the factors mucilage and soil moisture on a range of soil mechanical parameters in a sand and a loam. Both substrates were homogenised and filled into cylinders at bulk densities (ρb) of 1.26 and 1.47 g cm⁻³ for loam and sand, respectively. Chi ...
... Fast on‐site detection of potentially toxic metals in soils is crucial for soil remediation and contamination monitoring. The moisture in soils is a challenge for quantitative analysis of potentially toxic metals. Here, we used laser‐induced breakdown spectroscopy (LIBS) and partial least squares regression (PLSR) for fast on‐site quantitative analysis of potentially toxic metals in wet soil sampl ...
... Diffuse reflectance spectroscopy in the visible and near‐infrared (VNIR) spectral range has increasingly been utilised in recent years to measure soil properties, including organic carbon and macronutrient content, cation exchange capacity, pH, and even trace metal concentration. Proponents have even suggested that conventional laboratory soil testing methods can ultimately be replaced by these le ...
... Permanent grassland soils can act as a sink for carbon and may therefore positively contribute to climate change mitigation and adaptation. We compared young (5–15 years since latest grassland renewal) with old (>20 years since latest grassland renewal) permanent grassland soils in terms of carbon stock, carbon sequestration, drought tolerance and flood resistance. The research was carried out on ...
community structure; exchangeable potassium; grasslands; microbial communities; phospholipid fatty acids; potassium; soil water
Abstract:
... Fairy rings promoting circular greening belts in the vegetation can shape soil microbial communities by altering soil conditions. Knowledge about soil variables involved in this process is incomplete. We characterised the soil microbial communities of six fairy rings in a montane grassland using phospholipid fatty acid (PLFA) profiling, and studied if changes in soil properties corresponded to cha ...
... Cover crop use is a well‐established soil conservation technique and has been proven effective for erosion control and soil remediation in many arable systems. Whereas the obvious protection mechanism of cover crops occurs through the canopy, plant roots perform multiple functions. It is important to consider the soil functions delivered by different root systems in order to increase the uptake of ...
algorithms; carbon; chemometrics; data collection; hydrolysis; loess; model validation; monsoon season; principal component analysis; soil formation; summer
Abstract:
... Pedogenic weathering of aeolian materials plays an essential role in global nutrient and carbon cycling. A quick and effective approach for temporally high‐resolution and spatially large‐scale pedogenic investigations has long been needed. Here, we used visible and near‐infrared, mid‐infrared and sensor‐fused data to predict pedogenesis‐related soil properties (i.e., grain‐size distribution, clay‐ ...
... Soil liming to lower cadmium (Cd) bioavailability is challenged in perennial cacao orchards by the low penetration of lime in soils, not reaching deeper roots. Some studies suggest that gypsum (CaSO₄) could reduce Cd uptake by enhanced Ca²⁺:Cd²⁺ competition at the root surface. A pot experiment was conducted to identify soil conditions affecting gypsum efficacy in cacao plantlets (5‐month‐old CCN‐ ...
antibiotic resistance; antibiotic resistance genes; antibiotics; bacterial communities; community structure; metal tolerance; multiple drug resistance; phyllosphere; rhizoplane; rice; soil; soil microorganisms; tillering
Abstract:
... The soil antibiotic resistome is considered to be primarily determined by bacterial community composition. However, the antibiotic resistance of plant microbiota and its association with the soil microbiome in soil–plant systems remain largely unknown. Here, we studied the connections between bacteria and resistance genes (RGs) (mainly antibiotic resistance genes, ARGs) and mobile genetic elements ...
... Agricultural grass cultivars bred for increased forage yield commonly have extensive root systems. As roots are an important input of organic matter into the soil, it follows that such cultivars could lead to important increases in soil organic carbon (SOC), but this, and the mechanisms involved, are poorly understood with little empirical field evidence. We assessed the effect of two cultivars, L ...
... In dryland Mediterranean semi‐arid areas, the use of slurries and no‐till are encouraged to reduce costs. This paper evaluates the effect of such practices in terms of morphological changes of the topsoil porosity. The experiment had seven fertilization strategies (five of them including pig slurries applied at cereal sowing or at tillering) combined with no‐till or tillage by disc‐harrowing at so ...
... The stocks of phosphorus (P) in soil resulting from decades of over‐fertilisation can be used as a long‐term source of P provided that crop P bioavailability is ensured. This study was set up to identify to what extent soil organic matter (SOM) affects the long‐term availability of these stocks, the premise being that OM may limit irreversible P fixation in soil by blocking P sorption sites on ses ...
carbon sequestration; carbon sinks; dissolved organic carbon; field experimentation; no-tillage; soil organic carbon; soil quality; wheat; China
Abstract:
... The effect of conservation tillage on soil organic carbon (SOC) sequestration and crop production is controversial in semi‐arid areas. In addition, fertilisation is another essential factor affecting soil carbon pool and crop yields. We sought to explore the changes of SOC pool and crop productivity after optimising fertilisation and tillage. An 11‐year field experiment on the Loess Plateau in Chi ...
... Soil nitrogen (N) is controlled by several environmental factors. However, it is unclear how these factors and their interactions affect soil N fractions (SNFs) because of the lack of systematic N extraction methods. The Harbin–Dali belt, a transect more than 3,300 km long across China covering various climates, topographies, soil parent materials and vegetation types, was taken as the study area, ...
ecosystems; forest plantations; forestry development; forests; land use; nitrogen content; pH; phosphorus; sandy soils; soil texture; species richness; trees; Belgium
Abstract:
... Trees impact the chemical properties of the soil in which they grow. When planting forests, the choice of tree species and species combinations is thus expected to partly determine the spatial variation in soil properties, even in the early stages of forest development. We made use of a biodiversity‐ecosystem functioning experiment in Belgium, FORBIO (FORest BIOdiversity and Ecosystem Functioning) ...
... Local (cm) scale water loss distribution and evaporation in soil with flat and furrowed surfaces as a function of near‐surface wind speed and wind direction was investigated. Four levels of average main wind speed (10 cm above furrow ridge summits, 0, 1, 3 and 5 m·s⁻¹), three main wind directions (compared to the direction of the furrows, 0°, 45° and 90°) and two levels of relative air humidity (7 ...
... Over 50 years of the Green Revolution since the 1960s, the global population has increased by 2.5 times, cereal production by 3.3 times and the use of N, P and K fertilisers by 9.4, 4.2 and 4.3 times, respectively. Information is still limited, however, on the influence of these impacts on the fertility status of agricultural soils. Here we investigated the influence of the Green Revolution on 142 ...
biochar; bulk density; carbon; hydraulic conductivity; kilns; long term effects; porosity; sandy loam soils; silt loam soils; soil quality; soil texture; topsoil; water content; Belgium
Abstract:
... Besides its carbon (C) sequestration potential, biochar is being promoted as an amendment to improve soil quality. Burying biochar in soils is known to affect soil physical quality in the short‐term (<5 years), although the intensity of these effects depends on soil texture and biochar concentration especially. However, the long‐term effects of biochar remain largely unknown, yet are important to ...
agroecosystems; bacterial communities; carbon sequestration; carbon sinks; climate; community structure; fungal biomass; irrigation; soil microorganisms; soil organic carbon; soil water; soil water content; terrestrial ecosystems; topsoil; China
Abstract:
... Irrigation has become one of the main approaches to improve agricultural production in an arid area. The variation of soil moisture after irrigation has the potential to affect soil microbial community composition and soil organic carbon (SOC) storage, and thus, the imbalances in the terrestrial ecosystem carbon cycle. However, the impact of long‐term irrigation on the relationships between soil m ...
... Spatial soil applications frequently involve binomial variables. If relevant environmental covariates are available, using a Bayesian generalized linear model (BGLM) might be a solution for mapping such discrete soil properties. The geostatistical extension, a Bayesian generalized linear geostatistical model (BGLGM), adds spatial dependence and is thus potentially better equipped. The objective of ...