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1.
Stephen W. Potter Christar Kin Steven J. Hall John E. Sawyer Marshall D. McDaniel 《植物养料与土壤学杂志》2023,186(4):428-440
Background
Labile carbon (Clabile) limits soil microbial growth and is critical for soil functions like nitrogen (N) immobilization. Most experiments evaluating Clabile additions use laboratory incubations. We need to field-apply Clabile to fully understand its fate and effects on soils, especially at depth, but high cost and logistical difficulties hinder this approach.Aims
Here, we evaluated the impact of adding an in situ pulse of an inexpensive and 13C-depleted source of Clabile—crude glycerol carbon (Cglyc), a by-product from biodiesel production—to agricultural soils under typical crop rotations in Iowa, USA.Methods
We broadcast-applied Cglyc at three rates (0, 216, and 866 kg C ha−1) in autumn after soybean harvest, tracked its fate, and measured its impact on soil C and N dynamics to four depths (0–5, 5–15, 15–30, and 30–45 cm). Nineteen days later, we measured Cglyc in microbial biomass carbon (MBC), salt-extractable organic C, and potentially mineralizable C pools. We paired these measurements with nitrate N (NO3−–N) and potential net N mineralization to examine short-term effects on N cycling.Results
Cglyc was found to at least 45-cm depth with the majority in MBC (18%–23% of total Cglyc added). The δ13C values of the other measured C pools were too variable to accurately track the Clabile fate. NO3−–N was decreased by 13%–57% with the 216 and 866 kg C ha−1 rates, respectively, and was strongly related to greater microbial uptake of Cglyc (i.e., immobilization via microbial biomass). Crude glycerol application had minor effects on soil pH—the greatest rate decreased pH 0.18 units compared to the control.Conclusions
Overall, glycerol is an inexpensive and effective way to measure in situ, Clabile dynamics with soil depth—analogous to how mobile, dissolved organic C might behave in soils—and can be applied to rapidly immobilize NO3−–N. 相似文献2.
Jerry Celumusa Dlamini Eyob Habte Tesfamariam Robert Dunn J. Evans Jane Hawkins Martin Blackwell Adrian Collins Laura Cardenas 《植物养料与土壤学杂志》2023,186(4):406-416
Background
Riparian buffers are primarily implemented for their water quality functions in agroecosystems. Their location in the agricultural landscape allows them to intercept and process pollutants from immediately adjacent agricultural land. Vegetated riparian buffers recycle soil organic matter, which elevates soil carbon (C), which upon processing, processes and releases carbon dioxide (CO2). The elevated soil C and seasonally anoxic environments associated with riparian buffers promote denitrification and fermentation, further increasing soil CO2 production.Aim
Against this context, a replicated plot-scale experiment was established at North Wyke, UK, to measure the extent of soil CO2 emissions in permanent pasture served by grass, willow, and woodland riparian buffers, as well as a no-buffer control.Methods
Soil CO2 was measured using the static chamber technique in conjunction with soil and environmental variables between June 2018 and February 2019.Results
Cumulative soil CO2 fluxes were in the descending order: woodland riparian buffer; 11,927.8 ± 1987.9 kg CO2 ha–1 > no-buffer control; 11,101.3 ± 3700.4 kg CO2 ha–1 > grass riparian buffer; 10,826.4 ± 2551.8 kg CO2 ha–1 > upslope pasture; 10,554.6 ± 879.5 kg CO2 ha–1 > willow riparian buffer; 9294.9 ± 1549.2 5 kg CO2 ha–1. There was, however, no evidence of significant differences among all treatments of the current study.Conclusions
Despite the lack of significant differences, the results from our short-term study show that the woodland riparian buffer had relatively larger soil CO2 emissions than the remainder of the other riparian buffers and the upslope pasture it serves. Our short-term findings may be useful in developing soil CO2 mitigation strategies through careful selection of riparian buffer vegetation and may be useful in calibrating mechanistic models for simulating such emissions from similar agro systems. 相似文献3.
Carbon dynamics in subtropical forest soil: effects of atmospheric carbon dioxide enrichment and nitrogen addition 总被引:1,自引:0,他引:1
Juxiu X. Liu Guoyi Y. Zhou Deqiang Q. Zhang Zhihong H. Xu Honglang L. Duan Qi Deng Liang Zhao 《Journal of Soils and Sediments》2010,10(4):730-738
Purpose
The levels of atmospheric carbon dioxide concentration ([CO2]) are rapidly increasing. Understanding carbon (C) dynamics in soil is important for assessing the soil C sequestration potential under elevated [CO2]. Nitrogen (N) is often regarded as a limiting factor in the soil C sequestration under future CO2 enrichment environment. However, few studies have been carried out to examine what would happen in the subtropical or tropical areas where the ambient N deposition is high. In this study, we used open-top chambers to study the effect of elevated atmospheric [CO2] alone and together with N addition on the soil C dynamics in the first 4 years of the treatments applied in southern China. 相似文献4.
Background
Evidence of trivalent manganese (Mn3+) in the aqueous phase of soils is unknown so far although this strong oxidant has large environmental implications.Aims
We aimed to modify a spectrophotometric protocol (porphyrin method) and to discriminate between Mn2+ and Mn3+ in the aqueous phase of forest soils based on kinetic modeling.Methods
We investigated manganese speciation in 12 forest floor solutions and 41 soil solutions from an acidic forest site by adjusting pH and correcting for absorbance.Results
The solutions showed broad ranges in pH (3.4−6.3), dissolved organic carbon (DOC, 1.78−77.1 mg C L−1), and total Mn (MnT, 23.9−908 µg L−1). For acidic solutions, a pH-buffer was added to increase the pH of the solutions to 7.5−8.0, and background absorption was corrected for colored solutions, that is, solutions high in DOC. This was done to accelerate the reaction kinetics and avoid overestimation of MnT concentrations. After the pH and color adjustments, the comparison of MnT concentrations between the porphyrin method and optical emission spectrometry showed good agreement. Trivalent Mn, which is stabilized by organic ligands, constitutes significant proportions in both forest floor solutions (10−87%) and soil solutions (0.5−74%).Conclusions
The dissolved Mn3+ is present in acidic forest soils. Thus, we revise the paradigm that this species is not stable and encourage to apply the revised method to other soils. 相似文献5.
Georg Waldner Wolfgang Friesl-Hanl Georg Haberhauer Martin H. Gerzabek 《Journal of Soils and Sediments》2012,12(8):1292-1298
Purpose
The sorption behavior of the herbicide 4-chloro-2-methylphenoxyacetic acid (MCPA) to three different artificial soil mixtures was investigated. Artificial soils serve as model systems for improving understanding of sorption phenomena.Materials and methods
The soils consisted of quartz, ferrihydrite, illite, montmorillonite, and charcoal. In a previous study, several selected mixtures had been inoculated with organic matter, and microbial aging (incubation) had been performed for different periods of time (3, 12, and 18?months) before conducting the sorption experiments. The effect of this pre-incubation time on the sorption behavior was determined. Interaction of MCPA with soil surfaces was monitored by aqueous phase sorption experiments, using high-performance liquid chromatography/ultraviolet and in selected cases Fourier-transformed infrared spectroscopy.Results and discussion
The sorption behavior showed large differences between differently aged soils; Freundlich and linear sorption model fits (with sorption constants K f , 1/n exponents, and K d values, respectively) were given for pH?=?3 and the unbuffered pH of ??7. The largest extent of sorption from diluted solutions was found on the surfaces with a pre-incubation time of 3?months. Sorption increased at acidic pH values.Conclusions
Regarding the influence of aging of artificial soils, the following conclusions were drawn: young artificial soils exhibit stronger sorption at lower concentrations, with a larger K f value than aged soils. A correlation with organic carbon content was not confirmed. Thus, the sorption characteristics of the soils are more influenced by the aging of the organic carbon than by the organic carbon content itself. 相似文献6.
Nongma Zongo Juliane Dao Désiré Jean-Pascal Lompo Kathrin Stenchly Christoph Steiner Delphine Manka'abusi Michel Papaoba Sedogo Andreas Buerkert Rainer Georg Joergensen 《植物养料与土壤学杂志》2023,186(2):188-195
Background
Little is known about the effects of gypsum application to remediate saline–sodic soils in the tropics and the role of microbial indicators in soil reclamation.Aims
Our study aimed at (1) remediating a highly weathered, irrigated sodic Lixisol under prolonged urban crop production by clean water and gypsum application and (2) to determine the remediation effects on soil microbial indices.Methods
A three-factorial on-farm experiment with maize (Zea mays L.) was used to study effects on soil microbial biomass of (1) soil degradation at two levels of salinity, (2) irrigation with clean water and wastewater, and (3) the impact of added gypsum during a typical growing season.Results
At the high-degradation site, the 0.5 M K2SO4 extractable carbon (C) content was 40% higher than at the low-degradation site. In addition, microbial biomass carbon (MBC) and microbial biomass nitrogen (MBN) were 20% lower than at the low-degradation site, while fungal ergosterol was even 40% lower, leading to a 33% lower ergosterol/MBC ratio. Wastewater irrigation increased MBN but decreased ergosterol content at the low-degradation site while having no effect at the high-degradation site. Gypsum amendment led to higher MBN at the low-degradation site but to lower MBN at the high-degradation site. Gypsum amendment always increased the ergosterol content whereby this increase was stronger at the low-degradation site, especially in combination with wastewater irrigation.Conclusions
From a microbial perspective, high soil degradation levels should be avoided by treatment of a saline–sodic wastewater prior to its use for irrigation rather than relying on future remediation strategies of affected field sites. 相似文献7.
Irineu BianchiniJr Marcela Bianchessi da Cunha-Santino 《Journal of Soils and Sediments》2018,18(4):1232-1241
Purpose
We evaluated the decay of humic (HA) and fulvic acids (FA) in order to discuss the contribution of these substances as a sink and source of carbon in a tropical lagoon.Materials and methods
Experiments were conducted under aerobic and anaerobic conditions using FA and HA isolated from decomposition of Oxycaryum cubense submitted to 10 and 60 days of degradation. HA and FA were added to water samples from a tropical floodplain oxbow system, the Infernão Lagoon. The mineralization chambers were incubated in the dark at 21.0 °C. The carbon balance, electrical conductivity, pH, and optical density were measured over 95 days.Results and discussion
The results from the carbon budget were fitted with a first-order kinetics model. The mineralization of refractory fractions predominated for both FA and HA. Overall, although the mineralization pathway yields varied according to the type of resource and oxygen availability, the mineralization half-lives were quite similar (49 to 64 days), suggesting a similar microbial catabolism efficiency during the decay of humic substances. The short-term routes are represented by biochemical oxidations, and the immobilization and labile fractions (varying from 0 to 30%) of FA and HA supported these processes. A yield varying from 61.0 to 91.3% represents a carbon source degradation in the middle term (ca. 2 months) considering the ecosystem.Conclusions
In tropical floodplain lagoons, there are three carbon routes: (i) the IN1, representing a short-term pathway (hours to days) in the carbon transformation and (ii) IN3, a middle-term carbon source from HA and FA mineralization to the water column and subsequently to the atmosphere. A third route (IN2) supported the heterotrophic metabolism of the lagoon acting as a transitory sink of carbon.8.
Reducing CH<Subscript>4</Subscript> and CO<Subscript>2</Subscript> emissions from waterlogged paddy soil with biochar 总被引:1,自引:0,他引:1
Yuxue Liu Min Yang Yimin Wu Hailong Wang Yingxu Chen Weixiang Wu 《Journal of Soils and Sediments》2011,11(6):930-939
Purpose
A potential means to diminish increasing levels of CO2 in the atmosphere is the use of pyrolysis to convert biomass into biochar, which stabilizes the carbon (C) that is then applied to soil. Before biochar can be used on a large scale, especially in agricultural soils, its effects on the soil system need to be assessed. This is especially important in rice paddy soils that release large amounts of greenhouse gases to the atmosphere. 相似文献9.
A critical assessment of soil amendments (slaked lime/acidic fertilizer) for the phytomanagement of moderately contaminated shooting range soils 总被引:1,自引:1,他引:0
Hector M. Conesa Mirjam Wieser Björn Studer Maria N. González-Alcaraz Rainer Schulin 《Journal of Soils and Sediments》2012,12(4):565-575
Purpose
The effects of the addition of an acidic fertilizer solution and/or slaked lime (5.5 g Ca(OH)2 kg−1) on a slightly acidic shooting range soil (pH 6.1, % organic carbon 5.4) with moderate metal (e.g., 620 mg kg−1 Pb) and metalloid (17 mg kg−1 Sb) concentrations on metal and Sb solubility and plant accumulation were investigated. 相似文献10.
Juxiu Liu Guoyi Zhou Zhihong Xu Honglang Duan Yuelin Li Deqiang Zhang 《Journal of Soils and Sediments》2011,11(7):1155-1164
Purpose
Up to date, most studies about the plant photosynthetic acclimation responses to elevated carbon dioxide (CO2) concentration have been performed in temperate areas, which are often N limited under natural conditions and with low ambient N deposition. It is unclear whether photosynthetic downregulation is alleviated with increased N availability, for example, from increased N deposition due to fossil fuel combustion in the tropics and subtropics. Awareness of plant photosynthetic responses to elevated CO2 concentration will contribute to the better understanding and prediction of future forest productivity under global change. 相似文献11.
Weichun Yang David Lampert Na Zhao Danny Reible Wei Chen 《Journal of Soils and Sediments》2012,12(5):713-723
Purpose
The effects of black carbon (BC) on resistant desorption of organic pollutants in soil and sediment were evaluated to further understand the mechanisms for the resistant desorption and to find a more accurate desorption model which can improve risk assessment and management of ubiquitous soil/sediment contamination. 相似文献12.
Purpose
Genetic modification of Bt rice may affect straw decomposition and soil carbon pool under flood conditions. This study aims to assess the effects of cry gene transformation in rice on the residue decomposition and fate of C from residues under flooded conditions.Materials and methods
A decomposition experiment was set up using 13C-enriched rice straws from transgenic and nontransgenic Bt rice to evaluate the soil C dynamics and CH4 or CO2 emission rates in the root and non-root zones. The concentrations and stable carbon isotope compositions of the soil organic carbon (SOC), dissolved organic carbon (DOC), microbial biomass carbon (MBC), CH4, and CO2 of the root and non-root zones were determined from 7 to 110 days after rice straw incorporation.Results and discussion
Rice straw incorporation into soil significantly increased the SOC, DOC, and MBC concentrations and the CH4 and CO2 emission rates. The percentage of 13C-SOC remaining in the root zone was significantly lower than that in the non-root zone with rice straw decomposition. The DOC and MBC concentrations significantly increased in both the root and non-root zones between 0 and 80 days after rice straw incorporation. However, no significant differences were found after Bts (Bt rice straw added into soil) and Cks (nontransgenic Bt rice straw added into soil) incorporation in the root and non-root zones. This result may be attributed to the priming effects of sufficient oxygen and nutrients on straw degradation in the root zone.Conclusions
Bt gene insertion did not affect the SOC, DOC, and MBC concentrations and the CH4 and CO2 emission rates in both the root and non-root zones. However, rice straw incorporation and root exudation significantly increased the SOC, DOC, and MBC concentrations and the CH4 and CO2 emission rates. 相似文献13.
Xiaoyu Liu Yongcun Zhao Xuezheng Shi Yang Liu Shihang Wang Dongsheng Yu 《Journal of Soils and Sediments》2017,17(1):85-96
Purpose
Process-based models such as CENTURY have been extensively validated for simulating soil organic carbon (SOC) dynamics at the homogeneous plot scale. However, considerable uncertainty may exist when upscaling a simulation from the plot scale to a larger scale because of variation in the model inputs. The objectives of this study were to assess the uncertainty of CENTURY-modeled SOC and to identify the most influential model inputs in various upland regions of China.Materials and methods
Global sensitivity analysis was used to explore the sensitivity of CENTURY-modeled SOC to seven key model inputs. The uncertainties of the SOC simulated using various model inputs and climate-soil-management conditions were evaluated at 21 long-term monitoring sites located across upland areas in China.Results and discussion
The identified sensitive model inputs differed among regions and periods due to diverse climate-soil-management conditions; nevertheless, initial SOC content (SOCi), soil clay content, and crop residue removal rate (Residuerr) were the most influential inputs. The site-to-region upscaling uncertainties remained moderately large (±42.7, ±49.4, and ±69.3 % at the 90, 95, and 100 % confidence levels, respectively) when currently available observation data were used. Therefore, the collection of detailed information on soil properties and crop residue removal, particularly legacy soil data such as the SOCi and clay content, is important for reducing the uncertainties in SOC modeling.Conclusions
Data on SOCi, Residuerr, and clay content need to be collected prior to other input data to reduce input-related uncertainty and thus to provide more reliable SOC assessment at the regional or national scale in China.14.
Purpose
Light is a major driver of primary productivity in most ecosystems on Earth. Phototrophic microorganisms harvest light to synthesize organic biomass for sustaining the global energy and carbon flow. However, the bottom-up model of phototrophic microorganisms as primary production and food source for higher trophic levels remains unclear in the terrestrial environment. 相似文献15.
Background
In practical farming, there is often a need for short-term availability of information on the soil nutrient status.Aims
To develop a new express method for the extraction of major plant-available nutrients and measurement of soil nutrients. In future, this method shall serve for in-field measurements of soil samples with an ion-sensitive field-effect transistor (ISFET).Methods
Various extraction conditions such as type of extractant, soil-to-solution ratio, time, and intensity were investigated on a broad selection of dried soil samples in the laboratory. Based on 83 field-moist soil samples with varying clay contents, these conditions were compared to standard laboratory methods.Results
With increasing extraction time, the nutrient concentrations increased. When the soil-to-solution ratio was reduced, a greater share of nutrients was extracted, independent of soil type. H2O and 0.01 M CaCl2 and standard calcium-acetate-lactate (CAL) solution proved to be too weak in the short period to reach the ISFET sensor measurement range. Higher concentrated CAL solutions performed much better. Finally, a 5-min CaCl2 extraction followed by the removal of an aliquot for the determination of soil pH and NO3− was found to be effective. The remaining solution was then mixed with 0.20 M CAL solution for the analysis of H2PO4− and K+ at 10 min of extra extraction time. This extraction method showed very good correlations with the values based on the German laboratory reference methods for pH (R2 = 0.91) and for nitrate (R2 = 0.95). For phosphorus and potassium, we obtained an R2 of 0.70 and 0.81, respectively, for all soils. When soils were grouped according to clay content higher correlations were found.Conclusions
A new express method based on a wet-chemical approach with a soil preparation procedure was successfully developed and validated. This seems to be a valuable basis for future in-field measurements via ISFET. 相似文献16.
Fabien Leroy Sébastien Gogo Alexandre Buttler Luca Bragazza Fatima Laggoun-Défarge 《Journal of Soils and Sediments》2018,18(3):739-749
Purpose
The carbon sink function of peatlands is primarily driven by a higher production than decomposition of the litter Sphagnum mosses. The observed increase of vascular plants in peatlands could alter the decomposition rate and the carbon (C) cycle through a litter mixing effect, which is still poorly studied. Here, we examine the litter mixing effect of a peat moss (Sphagnum fallax) and two vascular plants (Pinus uncinata and Eriophorum vaginatum) in the field and laboratory-based experiment.Materials and methods
During the laboratory incubation, mass loss, CO2 production, and dissolved organic carbon concentration were periodically monitored during 51 days. The collected data were then processed in a C dynamics model. The calculated enzymatic activity was correlated to the measured β-glucosidase activity in the litter. In the field experiment, mass loss and CO2 production from litter bags were annually measured for 3 years.Results and discussion
Both laboratory and field experiments clearly show that the litter mixture, i.e., Sphagnum-Pinus-Eriophorum, had a synergistic effect on decomposition by enhancing the mass loss. Such enhanced mass loss increased the water extractable C and CO2 production in the litter mixture during the laboratory experiment. The synergistic effect was mainly controlled by the Sphagnum-Eriophorum mixture that significantly enhanced both mass loss and CO2 production. Although the β-glucosidase activity is often considered as a major driver of decomposition, mixing the litters did not cause any increase of the activity of this exo-enzyme in the laboratory experiment suggesting that other enzymes can play an important role in the observed effect.Conclusions
Mixing litters of graminoid and Sphagnum species led to a synergistic effect on litter decomposition. In a context of vegetation dynamics in response to environmental change, such a mixing effect could alter the C dynamics at a larger scale. Identifying the key mechanisms responsible for the synergistic effect on litter decomposition, with a specific focus on the enzymatic activities, is crucial to better predict the capacity of peatlands to act as C sinks.17.
Marianna Jagercikova Sophie Cornu Didier Bourlès Olivier Evrard Christine Hatté Jérôme Balesdent 《Journal of Soils and Sediments》2017,17(2):408-422
Purpose
Vertical transfer of solid matter in soils (bioturbation and translocation) is responsible for changes in soil properties over time through the redistribution of most of the soil constituents with depth. Such transfers are, however, still poorly quantified.Materials and methods
In this study, we examine matter transfer in four eutric Luvisols through an isotopic approach based on 137Cs, 210Pb(xs), and meteoric 10Be. These isotopes differ with respect to chemical behavior, input histories, and half-lives, which allows us to explore a large time range. Their vertical distributions were modeled by a diffusion-advection equation with depth-dependent parameters. We estimated a set of advection and diffusion coefficients able to simulate all isotope depth distributions and validated the resulting model by comparing the depth distribution of organic carbon (including 12/13C and 14C isotopes) and of the 0–2-μm particles with the data.Results and discussion
We showed that (i) the model satisfactorily reproduces the organic carbon, 13C, and 14C depth distributions, indicating that organic carbon content and age can be explained by transport without invoking depth-dependent decay rates; (ii) translocation partly explains the 0–2-μm particle accumulation in the Bt horizon; and (iii) estimates of diffusion coefficients that quantify the soil mixing rate by bioturbation are significantly higher for the studied plots than those obtained by ecological studies.Conclusions
This study presents a model capable of satisfactorily reproducing the isotopic profiles of several tracers and simulating the distribution of organic carbon and the translocation of 0–2-μm particles.18.
Temporal dynamics of iron-rich, tropical soil organic carbon pools after land-use change from forest to sugarcane 总被引:1,自引:0,他引:1
Wangang Deng Weidong Wu Hailong Wang Wei Luo Mark O. Kimberley 《Journal of Soils and Sediments》2009,9(2):112-120
Background, aim, and scope
Land-use change can significantly influence carbon (C) storage and fluxes in terrestrial ecosystems. Soil–plant systems can act as sinks or sources of atmospheric CO2 depending on formation and decomposition rates of soil organic matter. Therefore, changes in tropical soil C pools could have significant impacts on the global C cycle. This study aims to evaluate the impacts of long-term sugarcane cultivation on soil aggregation and organic matter, and to quantify temporal dynamics of soil organic matter in cultivated sugarcane plantation soils previously under a tropical natural secondary forest. 相似文献19.
Björn Kemmann Thorsten Ruf Reinhard Well Christoph Emmerling Roland Fuß 《植物养料与土壤学杂志》2023,186(1):79-94
Background
The sustainability of bioenergy is strongly affected by direct field-derived greenhouse gas (GHG) emissions and indirect emissions form land-use change. Marginal land in low mountain ranges is suitable for feedstock production due to small impact on indirect land-use change. However, these sites are vulnerable to high N2O emissions because of their fine soil texture and hydrology.Aims
The perennial cup plant (Silphium perfoliatum L.) might outperform silage maize (Zea mays L.) on cold, wet low mountain ranges sites regarding yield and ecosystem services. The aim of this study was to assess whether the cultivation of cup plant also provides GHG mitigation potential compared to the cultivation of maize.Methods
A t-year field experiment was conducted in a low mountain range region in western Germany to compare area and yield-scaled GHG emissions from cup plant and maize fields. GHG emissions were quantified using the closed chamber method.Results
Cup plant fields emitted an average of 3.6 ± 4.3 kg N2O-N ha–1 year–1 (–85%) less than maize fields. This corresponded to 74.0 ± 94.1 g CO2-eq kWh–1 (–78%) less emissions per produced electrical power. However, cup plant had a significantly lower productivity per hectare (–34%) and per unit of applied nitrogen (–32%) than maize.Conclusion
Cup plant as a feedstock reduces direct field-derived GHG emissions compared to maize but, due to lower yields cup plant, likely increases emissions associated with land-use changes. Therefore, the increased sustainability of bioenergy from biogas by replacing maize with cup plant is heavily dependent on the performance of maize at these sites and on the ecosystem services of cup plant in addition to GHG savings. 相似文献20.