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This paper focuses on collating legacy soil profile data and on the production of an updated national soil type map of Ethiopia, EthioSoilGrids version 1.0, using legacy data and a machine-learning approach. Given its quantitative digital representation, the map and the associated data make tremendous contributions to agricultural development planning and digital agricultural solutions, as well as improving the accuracy of global predictive soil mapping efforts.

Soil C saturation has been tested in several recent studies and led to a debate about its existence. We argue that, to test C saturation, one should pay attention to six fundamental principles: the right measures, the right units, the right dispersive energy and application, the right soil type, the right clay type, and the right saturation level. Once we take care of those six rights across studies, we find support for a maximum of C stabilized by minerals and thus soil C saturation.

The concept of soil aggregates is hotly debated, leading to confusion about their function or relevancy to soil processes. We propose that the use of conceptual figures showing detached and isolated aggregates can be misleading and has contributed to this skepticism. Here, we conceptually illustrate how aggregates can form and dissipate within the context of undisturbed soils, highlighting the fact that aggregates do not necessarily need to have distinct physical boundaries.

Our long-term modelling study examines the effects of multiple soil redistribution processes on carbon dynamics in a 200 km² catchment converted from natural forest to agriculture about 1000 years ago. The modelling results stress the importance of including tillage erosion processes and long-term land use and land management changes to understand current soil-redistribution-induced carbon fluxes at the landscape scale.

Earthworm invasion in North American forests can alter soil functioning. We investigated how the presence of invasive earthworms affected microbial communities, key drivers of soil biogeochemistry, across the major soil types of the Canadian boreal forest, which is a region largely understudied. Although total microbial biomass did not change, community composition shifted in earthworm-invaded mineral soils, where we also found higher fungal biomass and greater microbial species diversity.

Our paper presents a new web-based software tool to support soil process research. It is designed to categorize publications in this field according to site and soil characteristics, as well as experimental conditions, which is of critical importance for the interpretation of the research results. The software tool is provided open access for the soil science community such that anyone can contribute to improve the contents of the literature data base.

Twelve years after the nuclear accident that occurred in Fukushima in March 2011, radioactive contamination remains a major concern in north-eastern Japan. The Japanese authorities completed an unprecedented decontamination programme. The central objective was to not expose local inhabitants to excessive radioactive doses. At the onset of the full reopening of the Difficult-to-Return Zone in 2023, the current review provides an update of a previous synthesis published in 2019.

Conservation agriculture (CA), combining reduced or no tillage, permanent soil cover, and improved rotations, is often promoted as a climate-smart practice. However, our knowledge of the impact of CA on top- and subsoil soil organic carbon (SOC) stocks in the low-input cropping systems of sub-Saharan Africa is rather limited. Using two long-term experimental sites with different soil types, we found that mulch could increase top SOC stocks, but no tillage alone had a slightly negative impact.

This study investigated how land use, through its impact on soil geochemistry, might indirectly control soil organic carbon (SOC) content in tropical volcanic soils in Indonesia. We analyzed SOC fractions, substrate-specific mineralization, and net priming of SOC. Our results indicated that the enhanced formation of aluminum (hydr)oxides promoted aggregation and physical occlusion of OC, which is consistent with the lesser degradability of SOC in agricultural soils.

This work addresses air–ground temperature coupling and propagation into the subsurface in a mountainous area in central Spain using surface and subsurface data from six meteorological stations. Heat transfer of temperature changes at the ground surface occurs mainly by conduction controlled by thermal diffusivity of the subsurface, which varies with depth and time. A new methodology shows that near-surface diffusivity and soil moisture content changes with time are closely related.

Cover crops have substantial impacts on soil properties, but so far it is not clear how long a legacy effect of cover cropping will remain in the soil. We found that cover crops attenuate negative effects on soil structure that come from soil cultivation. The combination of plants with different litter qualities and rhizodeposits in biodiverse cover crop mixtures can improve the positive effects of cover cropping on soil structure amelioration.

We analyzed intensification of Uruguayan grasslands in a country-wide survey on fertility proxies, pH and trace metals in topsoils. We observed a loss of nutrients, trace metals and organic matter in grasslands, croplands and timber plantations and accumulation in riverine forests. This raises questions about the carrying capacity of Uruguayan soils with regard to currently implemented intensification strategies and supports more conservative forms of extensive grassland management.

Sediment source fingerprinting is a relevant tool to support soil conservation and watershed management in the context of accelerated soil erosion. To quantify sediment source contribution, it requires the selection of relevant tracers. We compared the three-step method and the consensus method and found very contrasted trends. The divergences between virtual mixtures and sample prediction ranges highlight that virtual mixture statistics are not directly transferable to actual samples.

The study was performed using continuous measurement of temporal variations in soil saturation and of the concentration of pesticides along the vadose zone profile and underlying alluvial aquifers at sugarcane fields in the Wet Tropics of Australia. A vadose zone monitoring system was set up to enable the characterization of pesticide (non-PS II herbicides) migration with respect to pesticide application, sugarcane growing period, and, finally, rainwater infiltration.

The fungal kingdom has been diversifying for more than 800 million years by colonizing a large number of habitats on Earth. Based on a unique dataset (18S rDNA meta-barcoding), we described the spatial distribution of fungal diversity at the scale of France and the environmental drivers by tackling biogeographical patterns. We also explored the fungal network interactions across land uses and climate types.

The present study used several different datasets, conducted a field survey, and paired the data with three different machine learning algorithms to construct spatial maps for areas at risk of land degradation for the Lut watershed in Iran. According to the land degradation map, almost the entire study region is at risk. A large fraction of 43 % of the area is prone to both high wind-driven and water-driven soil erosion.

We examined physical soil organic matter fractions to understand their relationship to temporal variability in crop yield at field scale. We found that interactions between crop productivity, topography, and climate led to variability in soil organic matter stocks among different yield stability zones. Our results imply that linkages between soil organic matter and yield stability may be scale-dependent and that particulate organic matter may be an indicator of unstable areas within croplands.

We added organic and inorganic nitrogen amendments to two soil types in a laboratory incubation study in order to understand how that would impact biodegradable plastic mulch (BDM) decomposition. We found that nitrogen amendments, particularly urea and inorganic nitrogen, suppressed BDM degradation in both soil types. However, we found limited impact of BDM addition on soil nitrification, suggesting that overall microbial processes were not compromised due to the addition of BDMs.

Structural stability is critical for sustainable agricultural soil management. We invented a simple test to measure soil structural stability. The QuantiSlakeTest consists of a dynamic weighting of a dried soil sample in water. The test is rapid, does not require expensive equipment and provides a high density of information on soil structural properties. With an open-access programme for data management under development, the test has strong potential for adoption by a large community of users.

Little effort has been made to develop methods to calculate the application rates of lime combined with organic amendments (OAs) needed to neutralise soil acidity and achieve the desired pH for plant growth. The previous approach of estimating appropriate lime and OA combinations based on field trials is time-consuming and costly. Hence, we developed and successfully validated a new method to calculate the amount of lime or OAs in combined applications required to ameliorate acidity.

Soil organic carbon (SOC) is key player in the global carbon cycle. Afforestation on pastures potentially alters organic matter input and SOC sequestration. We investigated the effects of a Picea abies L. afforestation sequence (0 to 130 years) on a former subalpine pasture on SOC stocks and dynamics. We found no difference in the SOC stock after 130 years of afforestation and thus no additional SOC sequestration. SOC composition was altered due to a modified SOC input following afforestation.

Sorption of mercury in soils, aquifer materials, and sediments is primarily linked to organic matter. Using column experiments, mercury concentration, speciation, and stable isotope analyses, we show that large quantities of mercury in soil water and groundwater can be sorbed to inorganic minerals; sorption to the solid phase favours lighter isotopes. Data provide important insights on the transport and fate of mercury in soil–groundwater systems and particularly in low-organic-matter systems.

This study investigated how the deposition of mineral dust delivered by the wind influences soil development in mountain environments. At six mountain locations in the southwestern United States, modern dust was collected along with samples of soil and local bedrock. Analysis indicates that at all sites the properties of dust and soil are very similar and are very different from underlying rock. This result indicates that soils are predominantly composed of dust delivered by the wind over time.

Tree cover has increased in grasslands worldwide, with juniper and oak trees expanding in the southern Great Plains, USA. Here, we examine how these changes interact with geology to affect soil C, N, and P storage. Soil concentrations of these elements were significantly higher under trees than grasslands but increased more under trees growing on Edwards soils. Our results suggest that geology and vegetation change should be considered when predicting soil storage in dryland ecosystems globally.

In this study, we systematically evaluated prospective crop transpiration benefits of sequestering soil organic carbon (SOC) under current and future climatic conditions based on the model SWAP. We found that adding at least 2% SOC down to at least 65 cm depth could increase transpiration annually by almost 40 mm, which can play a role in mitigating drought impacts in rain-fed cropping. Beyond this threshold, additional crop transpiration benefits of sequestering SOC are only marginal.

A carbon transport model was adjusted to study the importance of water and tillage erosion processes for particular microplastic (MP) transport across a mesoscale landscape. The MP mass delivered into the stream network represented a serious amount of MP input in the same range as potential MP inputs from wastewater treatment plants. In addition, most of the MP applied to arable soils remains in the topsoil (0–20 cm) for decades. The MP sink function of soil results in a long-term MP source.

Quantifying soil redistribution rates is a global challenge. Radiogenic tracers such as plutonium, namely ^239+240Pu, released to the atmosphere by atmospheric bomb testing in the 1960s are promising tools to quantify soil redistribution. Direct validation of ^239+240Pu as soil redistribution is, however, still missing. Here, we used a unique sediment yield time series in southern Italy, reaching back to the initial fallout of ^239+240Pu to verify ^239+240Pu as a soil redistribution tracer.

Vegetation restoration is an important method of ecological restoration that aims to control soil erosion and prevent soil degradation. Our study suggests that combinations of species such as C. korshinskii and L. bicolor are optimal for improving the soil nutrients and soil erodibility for any slope aspect. This study provides insight into the rational planning of vegetation restoration measures for slopes with various aspects in semi-arid areas of the northern agro-pastoral ecotone.

Forest soil is potentially an important source or sink of greenhouse gases (CO₂, N₂O, and CH₄), but this is affected by soil conditions. We studied how land inclination and soil/litter properties influence the flux of these gases. CO₂ and N₂O were more affected by inclination than CH₄; all were affected by soil/litter properties. This study underlines the importance of inclination and soil/litter properties in predicting greenhouse gas fluxes from forest soil and potential source–sink balance.

The aim of this study was to investigate the effects of different biopreparations on soil porosity, temperature, and CO₂ emission from the soil in northeast Europe (Lithuania) when growing food-type crops. The application of the biopreparations showed a cumulative effect on the soil properties. In the third year of the study, the total porosity of the soil was higher in all scenarios compared to the control, ranging between 51% and 74%.

We measured and modelled soil respiration, a key part of the biogenic carbon cycle, in different urban green space types to assess its dynamics in urban areas. We discovered surprisingly similar soil respiration across the green space types despite differences in some of its drivers and that irrigation of green spaces notably elevates soil respiration. Our results encourage further research on the topic and especially on the role of irrigation in controlling urban soil respiration.

The distribution of water-extractable colloids with soil profiles of 0–120 cm was investigated in a Vertisol under high-intensity agricultural management. A large number of experimental data show that colloidal phosphorus plays an important role in apatite transport throughout the profile. Thus, it is crucial to consider the impact of colloidal P when predicting surface-to-subsurface P loss in Vertisols.

We estimate the tendencies of copper (Cu) export in freshwater or accumulation in soils in Europe for the 21st century and highlight areas of importance for environmental monitoring. We develop a method combining computations of Cu partitioning coefficients between solid and solution phases with runoff data. The surfaces with potential for export or accumulation are roughly constant over the century, but the accumulation potential of Cu increases while leaching potential decreases for 2000–2095.

We evaluated the effect of soil management practices on decomposition at 29 sites (13 in Sweden and 16 in Austria) using long-term field experiments with the Tea Bag Index (TBI) approach. We found that the decomposition rate (k) and stabilization factor (S) were mainly governed by climatic conditions. In general, organic and mineral fertilization increased k and S, and reduced tillage increased S. Edaphic factors also affected k and S.

To rapidly obtain high-resolution soil pH data, pH sensors can measure the pH value directly in the field under the current soil moisture (SM) conditions. The influence of SM on pH and on its measurement quality was studied. An SM increase causes a maximum pH increase of 1.5 units. With increasing SM, the sensor pH value approached the standard pH value measured in the laboratory. Thus, at high soil moisture, calibration of the sensor pH values to the standard pH value is negligible.

This study investigated the performance of visual and near-infrared spectroscopy in six fields in Switzerland. Spectral models showed a good performance for soil properties related to organic matter at the field scale. However, spectral models performed best in fields with low mean carbonate content because high carbonate content masks spectral features for organic carbon. These findings help facilitate the establishment and implementation of new local soil spectroscopy projects.

Biological N₂ fixation helps to sustain carbon accumulation in peatlands and to remove CO₂ from the atmosphere. Changes in N₂ fixation may affect the dynamics of global change. Increasing inputs of reactive N from air pollution should lead to downregulation of N₂ fixation. Data from three N-polluted peat bogs show an interplay of N₂-fixation rates with 10 potential drivers of this process. N₂ fixation was measurable only at one site characterized by high phosphorus and low sulfate availability.

Subsoils in the tropics are not as extensively studied as those in temperate regions. In this study, the conversion of forest to agriculture in a subtropical region affected the concentration of stabilized organic carbon (OC) down to 90 cm depth, while no significant differences between 90 cm and 300 cm were detected. Our results suggest that subsoils below 90 cm are unlikely to accumulate additional stabilized OC through reforestation over decadal periods due to declining OC input with depth.

Cr pollution is a global concern. The use of methodologies specifically related to Cr toxicity is appropriate, such as the pollution-induced community tolerance (PICT) methodology. The development of PICT was determined in 10 soils after Cr addition in the laboratory. The Cr-soluble fraction and dissolved organic carbon were the main variables determining the development of PICT (R² = 95.6 %).

A new soil nitrate monitoring system that was installed in a cultivated field enabled us, for the first-time, to control nitrate concentration across the soil profile. Frequent adjustment of fertilizer and water application followed the actual dynamic variation in nitrate concentration across the soil profile. Hence, a significant reduction in fertilizer application was achieved while preserving optimal crop yield.

Changes in soil biological activity when microbial taxa interact remain little understood. To address this, we approach network analyses of ectomycorrhizal fungal communities. The study highlights how distinct fungi contribute to explaining community structure, whilst others mainly do for soil enzymatic activity. This differentiation between structural and functional roles of ectomycorrhizal fungi adds new insights to understand soil fungal community complexity and its functionality in soils.