Intensive agricultural management‐induced subsurface accumulation of labile phosphorus in Midwestern agricultural soils dominated by tile lines

Soil organic carbon (SOC) is essential for soil fertility and further represents a global carbon stock with potential to control atmospheric CO2 concentrations. Due to intense agricultural management, SOC is decreasing in many parts of the world, meaning that the soils act as CO2 sources rather than CO2 sinks, which they could have the capacity to be. Therefore, it is important to identify pertinent agricultural management practices that allow for high productivity, but at the same time allow for carbon sequestration and increase in SOC.In order to document changes in SOC, it is necessary to monitor SOC over decadal time scales, since changes occur slowly and are small as compared with existing stocks. The SOC content in Danish agricultural soils has been monitored at approx. 10-yr intervals (1986, 1997, 2009) since the first systematic national observations in 1986, where soils were sampled from a national 7 km x 7 km grid.In 2018, a new sampling campaign was conducted from the national 7 km x 7 km grid and soils were analysed for SOC to 1 m depth. The procedures applied in 2018 allowed for more precise relocation of the sampling points from 2009 as compared to precision obtained during the period from 1986-2009. Further, measurements in 2018 included assessment of soil bulk density and stone content in the upper 0-50 cm, which was not measured previously. Thus, one of the aims of the study was to evaluate how more precise point-specific information on bulk density and stone fractions affected the calculated SOC stocks across different soil types and management practices.The point-specific bulk density measured in 2018 were on average lower than the bulk densities used previously, which were retrieved from a database of texture-based soil classes. The volumetric stone fraction in the upper 0-50 cm was found to be <5% for roughly 90% of the soils, whereas <3% of the soils had stone fractions of >10%. On average, the inclusion of point-specific bulk density and stone fractions lead to approx. 5% lower SOC estimation, with equal approximmately contribution from the two variables.

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Soil organic carbon as an indicator of environmental quality at the national scale: Inventory monitoring methods and policy relevance

Canadian Journal of Soil Science ◽

10.4141/s04-087 ◽

2005 ◽

Vol 85 (Special Issue) ◽

pp. 531-540 ◽

Cited By ~ 28

Author(s):

Stephen M. Ogle ◽

Keith Paustian

Keyword(s):

Organic Carbon ◽

Soil Organic Carbon ◽

Environmental Quality ◽

New Technologies ◽

Agricultural Soils ◽

Agricultural Management ◽

Model Verification ◽

Monitoring Methods ◽

National Inventory ◽

Index Value

Soil organic carbon (SOC) storage is an indicator of environmental quality for mineral soils because of the influence that organic matter has on key functional properties, such as fertility, soil structure and water relations. Historically, agricultural management has caused large losses of SOC relative to native ecosystems, leading to degradation. However, new technologies and conservation practices have been developed during the past few decades that can enhance SOC storage, and thus improve environmental quality. Our objective was to describe a national inventory procedure to estimate SOC storage for purposes of monitoring environmental quality. The major steps in this procedure include: (1) model selection/development, (2) model verification, (3) identification of model input data, (4) uncertainty assessment, (5) model implementation, and (6) validation of results. Applying this approach with a simple C accounting method, the upper 30 cm of US agricultural soils were estimated to have accumulated 10.8 Tg C yr-1 between 1982 and 1997, with an uncertainty of ± 40%. A simple index was developed to relate estimated SOC stocks to the potential amounts under native conditions and conventional agricultural management. An index value of 0% on the proposed scale would be equivalent to the SOC under conventional a gricultural use, while an index value of 100% would be equivalent to native levels. With an estimated 1997 stock of 22 400 Tg C, the index value for US agricultural soils was about 60%. Using this inventory procedure, environmental issues related to soil, water and air quality could be informed by SOC in combination with other key indicators, in addition to using the inventory for evaluating sustainability of agricultural lands for food and fiber production. Key words: Natural resource inventory, environmental quality indicators, soil organic carbon, land use and management, national inventory, Organization for Economic Co-operation and Develop

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Resilience of agricultural soils to antibiotic resistance genes introduced by agricultural management practices

The Science of The Total Environment ◽

10.1016/j.scitotenv.2020.143699 ◽

2021 ◽

Vol 756 ◽

pp. 143699

Author(s):

Elena Radu ◽

Markus Woegerbauer ◽

Gerhard Rab ◽

Matthias Oismüller ◽

Peter Strauss ◽

...

Keyword(s):

Antibiotic Resistance ◽

Resistance Genes ◽

Management Practices ◽

Agricultural Soils ◽

Antibiotic Resistance Genes ◽

Agricultural Management

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Assessing the ability of soil tests to estimate labile phosphorus in agricultural soils: Evidence from isotopic exchange

Geoderma ◽

10.1016/j.geoderma.2018.09.048 ◽

2019 ◽

Vol 337 ◽

pp. 350-358 ◽

Cited By ~ 4

Author(s):

Sabina Braun ◽

Ruben Warrinnier ◽

Gunnar Börjesson ◽

Barbro Ulén ◽

Erik Smolders ◽

...

Keyword(s):

Isotopic Exchange ◽

Agricultural Soils ◽

Soil Tests ◽

Labile Phosphorus

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Subsoil Microbial Diversity and Stability in Rotational Cotton Systems

Soil Systems ◽

10.3390/soilsystems4030044 ◽

2020 ◽

Vol 4 (3) ◽

pp. 44 ◽

Cited By ~ 1

Author(s):

Katherine Polain ◽

Oliver Knox ◽

Brian Wilson ◽

Lily Pereg

Keyword(s):

Microbial Diversity ◽

Root System ◽

Beta Diversity ◽

Agricultural Soils ◽

Soil Depth ◽

Alpha Diversity ◽

Agricultural Management ◽

Illumina Platform ◽

Evenness Indices ◽

Sample Time

Microbial diversity has been well documented for the top 0–0.30 m of agricultural soils. However, spatio-temporal research into subsoil microbial diversity and the effects of agricultural management remains limited. Soil type may influence subsoil microbial diversity, particularly Vertosols. These soils lack distinct horizons and are known to facilitate the downward movement of organic matter, potentially supporting subsoil microbiota, removed from the crop root system (i.e., bulk soils). Our research used the MiSeq Illumina Platform to investigate microbial diversity down the profile of an agricultural Australian Vertosol to 1.0 m in bulk soils, as influenced by crop system (continuous cotton and cotton–maize) and sample time (pre- and in-crop samples collected over two seasons). Overall, both alpha- (Chao1, Gini–Simpson Diversity and Evenness indices) and beta-diversity (nMDS and Sørensen’s Index of Similarity) metrics indicated that both bacterial (16S) diversity and fungal (ITS) diversity decreased with increasing soil depth. The addition of a maize rotation did not significantly influence alpha-diversity metrics until 0.70–1.0 m depth in the soil, where bacterial diversity was significantly higher in this system, with beta-diversity measures indicating this is likely due to root system differences influencing dissolved organic carbon. Sample time did not significantly affect bacterial or fungal diversity over the two seasons, regardless of the crop type and status (i.e., crop in ground and post crop). The relatively stable subsoil fungal and overall microbial diversity in bulk soils over two crop seasons suggests that these microbiota have developed a tolerance to prolonged agricultural management.

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Regional characterization of N2O isotopic composition emitted from soils in view of land cover, agricultural management and annual cycles based on measurements and modeling

10.5194/egusphere-egu2020-15250 ◽

2020 ◽

Author(s):

Benjamin Wolf ◽

Edwin Haas ◽

David Kraus ◽

Ralf Kiese ◽

Klaus Butterbach-Bahl

Keyword(s):

Isotopic Composition ◽

Annual Cycle ◽

Agricultural Soils ◽

Temporal Trends ◽

Agricultural Management ◽

Biogeochemical Model ◽

High Temporal Resolution ◽

Global Budget ◽

Model Based ◽

Regional Estimates

While the global budget of nitrous oxide (N2O) is rather well constrained from a &#8220;top-down&#8221; perspective considering the change in the atmospheric burden and stratospheric N2O destruction, estimates of the various sources such as natural/agricultural soils, coastal areas or fossil fuel burning and industry remain uncertain. The isotopic composition of N2O, i.e., the relative abundances of the four most abundant isotopic species (14N14N16O, 15N14N16O, 14N15N16O, and 14N14N18O) have been identified as instrumental tools for attributing emissions to the corresponding production-consumption processes and to estimate the global budget. During the past two decades, N2O isotopic composition of individual sources has been investigated, and temporal trends in the isotopic composition of atmospheric N2O have been studied using and firn air and archived air samples collected in Antarctica. With regard to 15N and 18O in atmospheric N2O, a decreasing trend was consistently observed across studies, but contradictory results have been obtained for site preference (SP), i.e., the difference in the abundances of 15N14N16O and 14N15N16O relative to 14N14N16O. In addition, N2O isotopic composition for natural or agricultural soils rely on a limited amount of studies and usually cover only parts of the annual cycle.Since instruments used for optical isotope ratio spectroscopy (OIRS) can be deployed in the field, OIRS offers the opportunity to better characterize individual sources through long-term data in high temporal resolution. However, application of OIRS is challenging and, thus, remains scarce with regard to spatial resolution. For this reason, model-based regional estimates are pertinent to overcome the lack of regional estimates of N2O isotopic composition, to analyze trends, and to provide data for a refinement of the global budget.To obtain regional-scale (Switzerland) model-based estimates of N2O isotopic composition, we used data sets of measured N2O isotopic composition of two sites that are based on OIRS, and applied the Stable Isotope MOdel for Nutrient cyclEs, SIMONE in conjunction with the biogeochemical model LandscapeDNDC. Our results show that SIMONE/LandscapeDNDC was capable of reflecting especially SP, but also 15N-N2O at sites with different soil properties. For agricultural soils, our simulations revealed an annual cycle in SP, with higher values during the growing season, but not for 15N-N2O. We will also discuss effects of agricultural management on N2O emissions as well as temporal trends.

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Development of a Soil Quality Index for Soils under Different Agricultural Management Conditions in the Central Lowlands of Mexico: Physicochemical, Biological and Ecophysiological Indicators

Sustainability ◽

10.3390/su12229754 ◽

2020 ◽

Vol 12 (22) ◽

pp. 9754

Author(s):

Héctor Iván Bedolla-Rivera ◽

María de la Luz Xochilt Negrete-Rodríguez ◽

Miriam del Rocío Medina-Herrera ◽

Francisco Paúl Gámez-Vázquez ◽

Dioselina Álvarez-Bernal ◽

...

Keyword(s):

Soil Quality ◽

Quality Index ◽

Agricultural Soils ◽

Agricultural Practices ◽

Principal Component ◽

Agricultural Management ◽

Soil Quality Index ◽

Agricultural Industry ◽

Data Variability

The Bajío—Mexico’s central lowlands—is a region of economic importance because of its agricultural industry. Over time, agricultural practices have led to soil deterioration, loss of fertility, and abandonment. In this study, six agricultural soils were analyzed: AGQ, CTH, CTJ, JRM, CRC, and CYI, and used to develop a soil quality index (SQI) that includes the use of physicochemical, biological, and ecophysiological indicators to differentiate soil quality. Principal component analysis (PCA) was used, reducing the indicators from 46 to 4, which represents 80.4% of data variability. It was implemented the equation of additive weights using the variance of the principal components as a weight factor for the SQI. The developed SQI was according to the indicators WHC, SLT, N-NO3−, and qCO2, differentiating the quality of soils from the agricultural management in low quality (JRM < CYI < AGQ) and moderate quality (CTJ < CRC < CTH). The use of biological and ecophysiological indicators added to the PCA and the equation of additive weights allowed establishing an SQI with a minimum of indicators, sensitive to agricultural management, facilitating its interpretation and implementation for the Mexican Bajío region and soils in similar conditions around the world.

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