Search

A osteoartrite de joelhos é uma doença que afeta consideravelmente a qualidade de vida. O tratamento com o uso de fármacos ou medidas invasivas causa prejuízos aos doentes, evidenciando a importância do tratamento não farmacológico e não cirúrgico. Neste cenário, a busca por melhores condutas impulsiona o crescente o número de revisões sistemáticas sobre o tema. Contudo, também é observada uma baixa qualidade destas. Sendo assim, esse trabalho busca através do instrumento AMSTAR 2 identificar os possíveis preditores de qualidade bem como descrever o desempenho das metanálises usadas na revisão guarda-chuva “Efeito dos exercícios físicos na dor e na capacidade funcional de pacientes com osteoartrite dos joelhos: uma revisão guarda-chuva”. Este estudo cross seccional foi realizado usando o instrumento AMSTAR 2 e o software MATLAB. Os estudos foram classificados em alta, moderada, baixa ou criticamente baixa qualidade de acordo com o cumprimento dos domínios críticos e não críticos do instrumento e em sequência foi construído um score de porcentagem da contemplação dos itens do mesmo. Os resultados foram decepcionantes: das 23 revisões analisadas 22 apresentaram-se como criticamente baixa e uma como baixa. Dentre os fatores preditivos constaram como relevantes as Cocrhane reviews, o acesso livre e o financiamento externo. Diante disso é notória a necessidade dos autores de dominarem com maior destreza os pontos-chaves para a elaboração de um resultado com um menor risco de viés e os domínios críticos do instrumento. Posto isso, as conclusões encontradas na revisão guarda-chuva não apresentam relevância significativa, carecendo de novos estudos na área.

Assessing soil organic carbon biogeochemical stability is critical for estimating future changes in soil carbon stocks. Several methods for the assessment of soil organic carbon (SOC) biogeochemical stability have been proposed but very few can be implemented on large sample sets. Indeed, to date, only simple physical fractionation protocols (e.g. Lavallee et al., 2020) and Rock-Eval® thermal analysis techniques (Delahaie et al., 2022, SOIL discussion) have been implemented on data sets larger than a few hundred samples. Simple fractionation techniques allow separating a particulate organic carbon fraction (POC; considered labile) and an organic fraction associated with minerals (MaOC; considered more stable). Regarding thermal analyses, Rock-Eval® results associated to the PARTYsoc machine-learning model (Cécillon et al., 2021) provide a measure of the active (mean residence time of ca. 30 years) and centennially stable SOC fractions.In this study, we present the results of physical fractionations performed on ca. 1000 samples and thermal analyses performed on ca. 2000 samples from French mainland topsoils (RMQS program). We compare the amount and the drivers of each fraction. Our results show that most of the MaOC fraction is not stable at a centennial timescale. However, we show using a Random Forest model that the MaOC content and the centennially stable SOC content are similarly influenced by a common set of drivers: clay, pH and climatic conditions (mean annual temperature and mean annual precipitation). Finally, we discuss the complementarity of these two types of relatively high-throughput fractionation protocols. ReferencesCécillon, L., Baudin, F., Chenu, C., Christensen, B. T., Franko, U., Houot, S., Kanari, E., Kätterer, T., Merbach, I., van Oort, F., Poeplau, C., Quezada, J. C., Savignac, F., Soucémarianadin, L. N., & Barré, P. (2021). Partitioning soil organic carbon into its centennially stable and active fractions with machine-learning models based on Rock-Eval® thermal analysis (PARTY SOC v2. 0 and PARTY SOC v2. 0 EU). Geoscientific Model Development, 14(6), 3879-3898. Delahaie, A. A., Barré, P., Baudin, F., Arrouays, D., Bispo, A., Boulonne, L., Chenu, C., Jolivet, C., Martin, M. P., Ratié, C., Saby, N. P. A., Savignac, F., & Cécillon, L. (2022). Elemental stoichiometry and Rock-Eval® thermal stability of organic matter in French topsoils. EGUsphere, 1-31. Lavallee, J. M., Soong, J. L., & Cotrufo, M. F. (2020). Conceptualizing soil organic matter into particulate and mineral‐associated forms to address global change in the 21st century. Global Change Biology, 26(1), 261-273.

Carbon sequestration has become a buzz word and generates large expectations on ecosystems to take up carbon (C) from the atmosphere. These so-called negative emissions could compensate greenhouse gas emissions and help to stabilise the global climate. However, the term C sequestration is often misleadingly used fostering biased conclusions and exaggerated expectations. C sequestration is defined as net uptake of C from the atmosphere. Soils have a particularly large potential to take up C yet many soils currently continuously loose C. Measures to build up soil C may only reduce soil C losses (C loss mitigation) but will not result in a net C sequestration. While checking 100 recent papers we found only 5% correctly using the term C sequestration. Even worse, 13% of the papers used C sequestration equivalent to soil C stocks. Here we call for a rigorous and concise use of the term C sequestration and discuss implications of misleading applications.

Heterogeneity (spatial, temporal chemical and biological) is a fundamental property of soils. Although it is rarely explicitly accounted for in models of soil microbial functioning, it is a determinant of microbial access to substrate and therefore of microbial activity. Microbial adaptation to heterogeneity is also likely to play a significant role in determining microbial activity and therefore C persistence in soil. A more developed understanding of heterogeneity and how microbial communities interact with their heterogenous environment can help us better understand the mechanisms that regulate microbial activity and soil C dynamics, as well as offer potential avenues for upscaling. In this presentation I will show how microbial communities have adapted to spatial and molecular heterogeneity at the microbial scale and, through the use of a spatial explicit model, how spatial and molecular heterogeneity interact to reduce decomposition. Pore scale heterogeneity affects the distribution of both decomposers and organic matter. Using a stable isotope approach, I will show that, although there does not appear to be a clear relationship between microbial decomposer composition and pore size, a simple relationship emerges between pore size and microbial decomposition of organic substrate. As the pore size distribution of soils can be deduced from pedo-transfer functions, this relationship may provide a more mechanistic basis for the representation of moisture effects on C dynamics in larger scale models.

The implementation of agroecological practices can lead to an additional soil organic carbon (SOC) storage. The carbon sink effect will be more effective, even in the short and medium term, if the additional storage is realized in the form of persistent organic carbon (OC) and not in labile OC. The objective of this study was to evaluate the biogeochemical stability of additionally C stored by agroecological practices. Biogeochemical stability was assessed using particles size and density fractionation and Rock-Eval (RE) thermal analyses with PARTYsoc machine learning model. Samples were collected from the QualiAgro experiment, where organic wastes products (OWPs) including biowaste compost (BIOW), residual municipal solid waste compost (MSW) and farmyard manure (FYM) were applied, and from the La Cage experiment, where conservation (CA) and organic (ORG) agriculture had been established for 20 years. The plots that received the OWPs showed that 60-66% of the additional C was stored in mineral-associated organic matter (MAOM-C) and 29 - 39% in particulate organic matter (POM-C), whereas in CA and ORG, 77 - 84% of the additional C was stored in MAOM-C versus 15 - 23% in POM-C. While leading to additional C stocks of similar sizes, MSW and FYM exhibited higher proportions of the additionally stored C as POM-C (39 and 29% respectively) compared to CA (15%). This suggests a recalcitrance of POM under OWPs management compared to CA. The PARTYSOC model using RE thermal analysis parameters allows to predict the active (30 - 40 years) and stable (>100 years) carbon pools as defined in the AMG model. The results revealed that most, if not all, of the additional C belonged to the active C pool. These findings suggest that although additional SOC is mainly associated with MAOM-C, it is probably not stored in a form with a mean residence time exceeding ~30 years. The agroecological practices implemented in both long-term field experiments have resulted in substantial short-term additional C storage, but this storage will only be maintained at a high level if these storing practices are continued.

Over the last decade, the joint development of soil imaging tools and microscale models has made possible to start quantifying the role of soil architecture on soil functions and in particular on soil microbial activity. Microscale heterogeneity of soils have been considered to explain the microbial response, developing the concept of ‘hot-spots'. A major result highlighted from these studies is that spatial accessibility between the trophic resource and soil microorganisms is a key factor (Dungait et al., 2012). Under conditions of limited access, the decomposition of soil organic matter can be drastically reduced, whereas under conditions of optimal access the physiological traits of the microorganisms control the decomposition rate (Vogel et al., 2018). Interactions between soil architecture and microbial dynamics can also be indirect through the degree of soil pore aeration. For instance, the spatial accessibility between particulate organic matter and aerated soil pores can be related to the N2O production of soil samples (Ortega et al., 2023). New indicators quantifying the spatial accessibility are now emerging (Mbé et al., 2021 ; Rohe et al., 2021). Such spatial indicators of soil heterogeneity could feed the pedotransfer functions used to modulate organic matter decomposition rate in macroscale models of soil carbon dynamics. However the relevance and the robustness of these indicators to explain microbial activity remain to be evaluated (Schlüter et al., 2022). They have been established for static environmental conditions while soil architecture is highly dynamical, continuously changing under biotic and abiotic factors. Due to the complexity of obtaining sequential imaging datasets, few studies have imaged the 3D dynamics of soil architecture (Bottinelli et al., 2016). Mathematical models simulating the deformation of the 3D arrangement of solid particles using geomechanics laws for granular media (Duriez & Galusinski, 2021) or using fractal approaches for simplified soils (Perrier, 1995) have been developed. Other microscale modelling studies have attempted to simulate soil architecture dynamics through the action of microbes or physico-chemical processes using simplified rules (Crawford et al., 2012 ; Rupp et al., 2019). These incentive models have yet to be used to simulate microbial soil functions. We discuss these approaches and how they could be used to investigate to what extent the dynamics of soil architecture modifies the spatial accessibility between organic matter and microorganisms and in fine the soil organic matter decomposition rate. References:Bottinelli et al., 2016. Geoderma 65, 78-86.Crawford et al., 2012. J R Soc Interface 9, 1302-1310. Dungait et al., 2012. Global Change Biology 18, 1781-1796. Duriez & Galusinski, 2021. Computers & Geosciences 15, 104936.Mbé et al., 2021. Eur J Soil Sci., 13144Ortega et al., 2023. Geoderma, 116224. Perrier , 1995. PhD Thesis.Rupp et al., 2019. Front Environ Sci. 7, 170.Schlüter et al., 2022. Soil, 8, 253–267.Vogel et al., 2018. Ecological Modelling 383, 10-22.

Driving effectively soil research towards practice and towards policy solutions requires that the involved stakeholders, i.e researchers, practitioners and both national and regional policy makers interact and share information and views. However, these communities rather function in isolation. The European Joint Co-fund programme, EJP SOIL (Towards climate-smart and sustainable agricultural soil management) developed an innovative instrument to this end in each of its 24 participating countries.EJP SOIL National Hubs are committees of soil stakeholders (farmers, farmers advisors and farmers organisations, industry and agrobusiness, NGOs, local or national governance and policy implementing representatives, scientists), that were set either de-novo for the EJP SOIL or based on existing committees. Their mission is to (i) provide feedback to the EJP SOIL activities and outputs, (ii) voice national position and needs, (iii) contribute to and learn from the work done in research and iv) support in the dissemination of EJP SOIL outcomesThese entities appeared as precious assets for developing a science-policy-practice interface. As an example, the EJP SOIL National Hubs contributed to elaborating the roadmap of the programme and more recently were informed and provided feedback on the programme outputs on soil data harmonization and sharing and on soil monitoring in the perspective of the future European soil health law.We performed an analysis of their composition and functioning gives insights on how to effectively create and use these entities, which is forecasted by the EU Mission “A Soil Deal for Europe” for all land uses.

Climate-smart sustainable management of agricultural soil is critical to improve soil health, enhance food and water security, contribute to climate change mitigation and adaptation, biodiversity preservation, and improve human health and wellbeing. The European Joint Programme for Soil (EJP SOIL) started in 2020 with the aim to significantly improve soil management knowledge and create a sustainable and integrated European soil research system. EJP SOIL involves more than 350 scientists across 24 Countries and has been addressing multiple aspects associated with soil management across different European agroecosystems. This study summarizes the key findings of stakeholder consultations conducted at the national level across 20 countries with the aim to identify important barriers and challenges currently affecting soil knowledge but also assess opportunities to overcome these obstacles. Our findings demonstrate that there is significant room for improvement in terms of knowledge production, dissemination and adoption. Among the most important barriers identified by consulted stakeholders are technical, political, social and economic obstacles, which strongly limit the development and full exploitation of the outcomes of soil research. The main soil challenge across consulted member states remains to improve soil organic matter and peat soil conservation while soil water storage capacity is a key challenge in Southern Europe. Findings from this study clearly suggest that going forward climate-smart sustainable soil management will benefit from (1) increases in research funding, (2) the maintenance and valorisation of long-term (field) experiments, (3) the creation of knowledge sharing networks and interlinked national and European infrastructures, and (4) the development of regionally-tailored soil management strategies. All the above-mentioned interventions can contribute to the creation of healthy, resilient and sustainable soil ecosystems across Europe.

Soils store vast amounts of carbon (C) on land, and increasing soil organic carbon (SOC) stocks in already managed soils such as croplands may be one way to remove C from the atmosphere, thereby limiting subsequent warming. The main objective of this study was to estimate the amount of additional C input needed to annually increase SOC stocks by 4‰ at 16 long-term agricultural experiments in Europe, including exogenous organic matter (EOM) additions. We used an ensemble of six SOC models and ran them under two configurations: (1) with default parametrization and (2) with parameters calibrated site-by-site to fit the evolution of SOC stocks in the control treatments (without EOM). We compared model simulations and analysed the factors generating variability across models. The calibrated ensemble was able to reproduce the SOC stock evolution in the unfertilised control treatments. We found that, on average, the experimental sites needed an additional 1.5 ± 1.2 Mg C ha−1 year−1 to increase SOC stocks by 4‰ per year over 30 years, compared to the C input in the control treatments (multi-model median ± median standard deviation across sites). That is, a 119% increase compared to the control. While mean annual temperature, initial SOC stocks and initial C input had a significant effect on the variability of the predicted C input in the default configuration (i.e., the relative standard deviation of the predicted C input from the mean), only water-related variables (i.e., mean annual precipitation and potential evapotranspiration) explained the divergence between models when calibrated. Our work highlights the challenge of increasing SOC stocks in agriculture and accentuates the need to increasingly lean on multi-model ensembles when predicting SOC stock trends and related processes. To increase the reliability of SOC models under future climate change, we suggest model developers to better constrain the effect of water-related variables on SOC decomposition. This work benefited from the French state aid managed by the ANR under the “Investissements d'avenir” programme with the reference ANR-16-CONV-0003 (CLAND project). EB, RZA and BG are supported by the European Union's Horizon 2020 research and innovation program under grant agreement No 101000289 (Holisoils project). RZA was also supported by the United States Department of Energy, Office of Science, and Office of Biological and Environmental Research. Oak Ridge National Laboratory is managed by UT-Battelle, LLC, for the United States Department of Energy under contract DE-AC05-00OR22725.

Global warming is leading to increased temperatures, accentuated evaporation of terrestrial water and increased the atmosphere moisture content, resulting in frequent droughts and heavy precipitation events. It necessary to assess the sensitivity of soil organic carbon (SOC) under storing practices in response to increasing soil moisture, temperature and frequent dry-wet cycles in order to anticipate future soil carbon losses. We evaluated the impact of these climatic events through an incubation experiment on temperate luvisols from conservation agriculture, organic agriculture, organic waste products applications, i.e. biowaste, residual municipal solid waste and farmyard manure composts compared with conventionally managemed soils. The alternative management options all have led to increased SOC stocks. Soil samples were incubated in the lab under different temperatures (20, 28 and 35°C), different moisture conditions (pF1.5; 2.5 and 4.2) and under dry(pF4.2)-wet (pF1.5) cycles. Dry-wet cycles caused CO2 flushes but overall did not stimulate soil carbon mineralization relative to wet controls (pF1.5 and pF2.5). Overall the additional SOC stored under alternative management options was not more sensitive to climate change (temperature, moisture, dry-wet cycles) than the existing SOC.

Soil carbon is the major active pool of terrestrial carbon, and as such, soil organic carbon (SOC) targets, policies and measures will be pivotal to achieving global climate targets. SOC sequestrat...

Partitioning soil organic carbon (SOC) into two kinetically different fractions that are stable or active on a century scale is key for an improved monitoring of soil health and for more accurate models of the carbon cycle. However, all existing SOC fractionation methods isolate SOC fractions that are mixtures of centennially stable and active SOC. If the stable SOC fraction cannot be isolated, it has specific chemical and thermal characteristics that are quickly (ca. 1 h per sample) measurable using Rock-Eval® thermal analysis. An alternative would thus be to (1) train a machine-learning model on the Rock-Eval® thermal analysis data for soil samples from long-term experiments for which the size of the centennially stable and active SOC fractions can be estimated and (2) apply this model to the Rock-Eval® data for unknown soils to partition SOC into its centennially stable and active fractions. Here, we significantly extend the validity range of a previously published machine-learning model (Cécillon et al., 2018) that is built upon this strategy. The second version of this model, which we propose to name PARTYSOC, uses six European long-term agricultural sites including a bare fallow treatment and one South American vegetation change (C4 to C3 plants) site as reference sites. The European version of the model (PARTYSOCv2.0EU) predicts the proportion of the centennially stable SOC fraction with a root mean square error of 0.15 (relative root mean square error of 0.27) at six independent validation sites. More specifically, our results show that PARTYSOCv2.0EU reliably partitions SOC kinetic fractions at its northwestern European validation sites on Cambisols and Luvisols, which are the two dominant soil groups in this region. We plan future developments of the PARTYSOC global model using additional reference soils developed under diverse pedoclimates and ecosystems to further expand its domain of application while reducing its prediction error.

The influence of dry-wet cycles (DWC) on soil organic carbon (SOC) decomposition is still debated given the somehow controversial results observed in the literature. The objective of this study was to evaluate the effects of DWC on SOC mineralization relative to various moisture controls in 7 treatments from two long-term French field experiments presenting contrasted SOC concentrations. We conducted a laboratory incubation to quantify CO2 emissions upon four soil moisture scenarios: continuously wet (WET), continuously moderately wet (MWET), continuously dry (DRY) and dry-wet cycles (DWC). We also calculated the SOC mineralization that would correspond to the average water content in DWC (mean_DWC). Our results showed that across all treatments the daily carbon mineralization rate increased with soil moisture (WET>MWET>DRY). In DWC scenario, mineralization rates fluctuated with the changes in soil moisture. As soils dried, daily mineralization rates decreased and the subsequent soil rewetting, to pF 1.5, caused a rapid mineralization flush or "Birch effect". However, these flushes did not compensate for the low mineralization rates in the drying phase as the cumulative mineralization was not higher in the DWC scenario compared to the mean_DWC which was the scenario with equivalent water content as the DWC. We also observed that not accounting the CO2 emissions in the drying phase could lead to an overestimation of the effect of DWC. We recommend to measure continuously the soil respiration during dry-wet experiments and to compare the CO2 emitted in DWC with a control that has a water content equivalent to the average water content in DWC. In addition, we questioned the importance of the effect of dry-wet cycles on overall soil respiration.

There is growing international interest in better managing soils to increase soil organic carbon (SOC) content to contribute to climate change mitigation, to enhance resilience to climate change and to underpin food security, through initiatives such as international ‘4p1000’ initiative and the FAO's Global assessment of SOC sequestration potential (GSOCseq) programme. Since SOC content of soils cannot be easily measured, a key barrier to implementing programmes to increase SOC at large scale, is the need for credible and reliable measurement/monitoring, reporting and verification (MRV) platforms, both for national reporting and for emissions trading. Without such platforms, investments could be considered risky. In this paper, we review methods and challenges of measuring SOC change directly in soils, before examining some recent novel developments that show promise for quantifying SOC. We describe how repeat soil surveys are used to estimate changes in SOC over time, and how long‐term experiments and space‐for‐time substitution sites can serve as sources of knowledge and can be used to test models, and as potential benchmark sites in global frameworks to estimate SOC change. We briefly consider models that can be used to simulate and project change in SOC and examine the MRV platforms for SOC change already in use in various countries/regions. In the final section, we bring together the various components described in this review, to describe a new vision for a global framework for MRV of SOC change, to support national and international initiatives seeking to effect change in the way we manage our soils., Since soil organic carbon (SOC) changes are difficult to measure, a key barrier to implementing programmes to increase SOC is the need for credible and reliable measurement/monitoring, reporting and verification (MRV) platforms. We review methods for measuring SOC change directly in soils, examine novel developments for quantifying SOC change and describe how surveys, long‐term experiments and chronosequences can be used for testing models and as benchmark sites in global frameworks to estimate SOC change. We review MRV platforms for soil organic carbon change already in use and describe a new vision for a global framework for MRV of SOC change.

Soil organic matter (SOM) is widely recognized as of critical importance for both soil quality and climatic mitigation. The quality and quantity of SOM are key to assess the characteristics of soils, and thus must be accurately monitored in order to protect the integrity of soils. In the last few years, a thermal analysis technique called Rock-Eval® that provides insights on bulk SOM chemistry and thermal stability has been recognized as a powerful method for SOM characterization. It can moreover be applied on large sets of samples.The RMQS is the French monitoring network of soil quality. The first sampling campaign took place from 2000 to 2015 and resulted – among others – in about 2200 composite surface (0-30 cm) samples taken all over France. It represents an unprecedented collection of precise and complete data on French soils.We observed significant effects of land cover on both SOM thermal stability and bulk chemistry. The mean values of hydrogen index (HI, which is a proxy for SOM H/C ratio) for arable lands (190.5 ± 43.4 mg HC per g of SOC, n=786) was lower than for grassland soils (228.4 ± 46.3 mg HC per g of SOC, n=486) and forest soils (240.4 ± 66.4 mg HC per g of SOC, n=528). Regarding the oxygen index (OIre6, which is a proxy of SOM O/C ratio), we observed significantly different values (P2 per g of SOC), grassland soils (172.4 ± 26.8 mg O2 per g of SOC) and forest soils (164.2 ± 29.6 mg O2 per g of SOC). We also observed that thermal stability of SOM was significantly higher in cropland soils compared to grassland and forest soils. Our data suggest that topsoil SOM is on average more oxidized and biogeochemically stable in croplands. Further analyses will investigate the influence of pedo-climatic conditions on SOM characteristics.The high number and even repartition of data on the French territory allow for the constitution of a national interpretative referential for these indicators. The Rock-Eval® parameters will also be used to calculate the centennially stable SOC fraction using the PARTYsocv2.0 model and map it at the scale of France.

Changes in soil organic carbon (SOC) stocks are a major source of uncertainty for the evolution of atmospheric CO2 concentration during the 21st century. They are usually simulated by models dividing SOC into conceptual pools with contrasted turnover times. The lack of reliable methods to initialize these models, by correctly distributing soil carbon amongst their kinetic pools, strongly limits the accuracy of their simulations. Here, we demonstrate that PARTYSOC, a machine-learning model based on Rock-Eval® thermal analysis, optimally partitions the active- and stable-SOC pools of AMG, a simple and well-validated SOC dynamics model, accounting for effects of soil management history. Furthermore, we found that initializing the SOC pool sizes of AMG using machine learning strongly improves its accuracy when reproducing the observed SOC dynamics in nine independent French long-term agricultural experiments. Our results indicate that multi-compartmental models of SOC dynamics combined with a robust initialization can simulate observed SOC stock changes with excellent precision. We recommend exploring their potential before a new generation of models of greater complexity becomes operational. The approach proposed here can be easily implemented on soil monitoring networks, paving the way towards precise predictions of SOC stock changes over the next decades.

Earthworm activities in soil generate biogenic aggregates (casts), the mass of which can reach up to 30 - 50t/ha. The dynamics of organic matter (OM) is strongly constrained (accessibility, O2 content, etc.) within these structures and they tend to have high OM contents. As a result of their large mass and high OM contents, these aggregates can have significant effects on OM dynamics and protection over distinct time scales: (i) over the short term, earthworms increase OM mineralization through their own metabolic processes and by stimulating soil microbial activity, the so-called priming effect; (ii) over longer terms, during cast ageing, a new equilibrium may be reached, leading to the protection of the incorporated OM. However few incubation studies have been conducted for more than three months. Consequently, the net influence of earthworm’s casts on the OM dynamics is still poorly understood and remains to be determined.Our objective was to estimate whether the incorporation of fresh OM into casts leads to its protection or to an enhanced degradation during the period of cast ageing. To do so, we compared the fate of 13C labeled fresh OM added to bulk soil to the fate of fresh OM ingested by earthworms (L. Terrestris) in mesocosms, and monitored OM mineralization during one year. The incorporation of fresh OM into casts was also determined as were the microbial communities involved in the consumption of labelled OM (via 13C-phospholipid fatty acid analysis). In addition, the OM stability was estimated as the proportion of mineral associated.The results showed that fresh OM was largely incorporated into casts, with significant differences in the mineralization rates obtained for the OM incorporated into the soil, compared with that incorporated into the casts. This difference decreased over time, as the casts aged. Fungal activity was lower when OM was incorporated in casts. In conclusion, earthworms influence the fate of fresh OM in soil by delaying its mineralization but do not lead to long-term stabilization.

We have read with interest an opinion paper recently published in the European Journal of Soil Science (Berthelin et al., 2022). This paper presents some interesting considerations, at least one of which is already well known to soil scientists working on soil organic carbon (SOC), that is, a large portion (80%–90%) of fresh carbon inputs to soil is subject to rapid mineralization. The short-term mineralization kinetics of organic inputs is well-known and accounted for in soil organic matter models. Thus, clearly, the long-term predictions based on these models do not overlook short-term mineralization. We point out that many agronomic practices can significantly contribute to SOC sequestration. If conducted responsibly whilst fully recognising the caveats, SOC sequestration can lead to a win-win situation where agriculture can both contribute to the mitigation of climate change and adapt to it, whilst at the same time delivering other co-benefits such as reduced soil erosion and enhanced biodiversity., European Journal of Soil Science, 73 (3), ISSN:1351-0754, ISSN:1365-2389

The importance of soils to society has gained increasing recognition over the past decade, with the potential to contribute to most of the United Nations’ Sustainable Development Goals (SDGs). With unprecedented and growing demands for food, water and energy, there is an urgent need for a global effort to address the challenges of climate change and land degradation, whilst protecting soil as a natural resource. In this paper, we identify the contribution of soil science over the past decade to addressing gaps in our knowledge regarding major environmental challenges: climate change, food security, water security, urban development, and ecosystem functioning and biodiversity. Continuing to address knowledge gaps in soil science is essential for the achievement of the SDGs. However, with limited time and budget, it is also pertinent to identify effective methods of working that ensure the research carried out leads to real-world impact. Here, we suggest three strategies for the next decade of soil science, comprising a greater implementation of research into policy, interdisciplinary partnerships to evaluate function trade-offs and synergies between soils and other environmental domains, and integrating monitoring and modelling methods to ensure soil-based policies can withstand the uncertainties of the future. Highlights: We highlight the contributions of soil science to five major environmental challenges since 2010. Researchers have contributed to recommendation reports, but work is rarely translated into policy. Interdisciplinary work should assess trade-offs and synergies between soils and other domains. Integrating monitoring and modelling is key for robust and sustainable soils-based policymaking.

Partitioning soil organic carbon (SOC) into two kinetically different fractions that are centennially stable or active is key information for an improved monitoring of soil health and for a more accurate modelling of the carbon cycle. However, all existing SOC fractionation methods isolate SOC fractions that are mixtures of centennially stable and active SOC. If the stable SOC fraction cannot be isolated, it has specific chemical and thermal characteristics that are quickly (ca. 1 h per sample) measureable using Rock-Eval® thermal analysis. An alternative would thus be to (1) train a machine-learning model on the Rock-Eval® thermal analysis data of soil samples from long-term experiments where the size of the centennially stable and active SOC fractions can be estimated, and (2) apply this model on the Rock-Eval® data of unknown soils, to partition SOC into its centennially stable and active fractions. Here, we significantly extend the validity range of the machine-learning model published by Cécillon et al. [Biogeosciences, 15, 2835–2849, 2018, https://doi.org/10.5194/bg-15-2835-2018], and built upon this strategy. The second version of this statistical model, which we propose to name PARTYSOC, uses six European long-term agricultural sites including a bare fallow treatment and one South American vegetation change (C4 to C3 plants) site as reference sites. The European version of the model (PARTYSOCv2.0EU) predicts the proportion of the centennially stable SOC fraction with a conservative root-mean-square error of 0.15 (relative root-mean-square error of 0.27) in a wide range of agricultural topsoils from Northwestern Europe. We plan future expansions of the PARTYSOC global model using additional reference soils developed under diverse pedoclimates and ecosystems, and we already recommend the application of PARTYSOCv2.0EU in European agricultural topsoils to provide accurate information on SOC kinetic pools partitioning that may improve the simulations of simple models of SOC dynamics.

The largest terrestrial organic carbon pool, carbon in soils, is regulated by the intricate connection between plant carbon inputs, microbial activity, and soil matrix. This is manifested by how microorganisms, the key players in transforming plant-derived carbon into soil organic carbon, are controlled by the physical arrangement of organic and inorganic soil particles. We studied the role of soil structure on the fate of litter-derived organic matter and we propose that the persistence of soil carbon pools is directly determined at plant–soil interfaces. We show that while microbial activity and fungal growth is controlled by soil structure, occlusion of organic matter into aggregates and formation of organo-mineral associations occur in concert on litter surfaces regardless of soil structure. These two mechanisms—the two most prominent processes contributing to the persistence of organic matter—occur directly at fresh litter that constitutes a key nucleus in the build-up of soil carbon persistence.

International audience; The operationally defined fraction of soil organic matter (SOM), glomalin-related soil protein (GRSP), has been reported to be particularly stable. This is the first study to test this hypothesis. Archived soil has been used from the long-term bare fallow trial, known as the 42-Plots, in Versailles, France. With no input from plants for 80 years, changes in GRSP must result from either turnover of SOM or net mineralization. Intrinsically, stability of protein would lead to progressive enrichment in GRSP. Soils from treatments that influenced pH, soil C:N ratio and physical stability were studied. Soil having received manure amendment was also studied to give contrasting microbial activity. Both GRSP and soil organic carbon (SOC) contents declined over the 80-year period, with the exception of the manure treatment. GRSP and SOC contents were positively correlated. SOC was continuously enriched in GRSP in the control treatment, suggesting greater stability of GRSP. The SOC in manure-amended soil was also progressively enriched in GRSP, but this can be attributed to the GRSP content of added manure. For the other treatments, the ratio GRSP:SOC fell continuously (CaCO3 amendment) or fell to a minimum value after 45 years (KCl amendment) or levelled off after a progressive increase ((NH4)2SO4 amendment). Trends are compared with measured soil properties and changes in microbial activity inferred from soil pH. No reliable independent assessment of microbial composition of these archived soils is possible. The results cannot be explained by inherent chemical or physicochemical stability of GRSP. We conclude that recycling of SOM continually produces soil protein. The net change in GRSP content is a complex function of SOM cycling and protein mineralization. These findings add to the increasing body of evidence that the operationally defined fraction of SOM known as GRSP does not predominantly originate from arbuscular mycorrhizal fungal activity. Highlights: Processes determining SOM enrichment in GRSP in C-depleted soils are not understood. GRSP decreased along with SOC, but relative rates of decline varied with amendments. Levels of GRSP appear to be due to organic matter turnover as well as mineralization. GRSP does not appear to originate from arbuscular mycorrhizal fungal activity.

This paper stemmed from a workshop 'Emerging challenges in large scale soil carbon sequestration' held in Paris on 8-10 October 2018; International audience; To respect the Paris agreement targeting a limitation of global warming below 2°C by 2100, and possibly below 1.5°C, drastic reductions of greenhouse gas emissions are mandatory but not sufficient. Large‐scale deployment of other climate mitigation strategies are also necessary. Among these, increasing soil organic carbon (SOC) stocks is an important lever because carbon in soils can be stored for long periods and land management options to achieve this already exist and have been widely tested. However, agricultural soils are also an important source of nitrous oxide (N$_2$O), a powerful greenhouse gas, and increasing SOC may influence N$_2$O emissions, likely causing an increase in many cases, thus tending to offset the climate change benefit from increased SOC storage. Here, we review the main agricultural management options for increasing SOC stocks. We evaluate the amount of SOC that can be stored as well as resulting changes in N$_2$O emissions to better estimate the climate benefits of these management options. Based on quantitative data obtained from published meta‐analyses and from our current level of understanding, we conclude that the climate mitigation induced by increased SOC storage is generally overestimated if associated N$_2$O emissions are not considered but, with the exception of reduced tillage, is never fully offset. Some options (e.g, biochar or non‐pyrogenic C amendment application) may even decrease N$_2$O emissions.; Pour respecter l'accord de Paris visant à limiter le réchauffement climatique à moins de 2°C d'ici 2100, et éventuellement à moins de 1,5°C, des réductions drastiques des émissions de gaz à effet de serre sont obligatoires mais pas suffisantes. Le déploiement à grande échelle d'autres stratégies d'atténuation du climat est également nécessaire. Parmi celles-ci, l'augmentation des stocks de carbone organique du sol (SOC) est un levier important car le carbone dans les sols peut être stocké pendant de longues périodes et les options de gestion des terres pour y parvenir existent déjà et ont été largement testées. Toutefois, les sols agricoles sont également une source importante d'oxyde nitreux (N$_2$O), un puissant gaz à effet de serre, et l'augmentation du SOC peut influer sur les émissions de N$_$O, provoquant probablement une augmentation dans de nombreux cas, tendant ainsi à compenser le bénéfice du changement climatique résultant du stockage accru du SOC. Nous passons ici en revue les principales options de gestion agricole pour l'augmentation des stocks de SOC. Nous évaluons la quantité de SOC qui peut être stockée ainsi que les changements qui en résultent dans les émissions de N$_2$O afin de mieux estimer les avantages climatiques de ces options de gestion. Sur la base des données quantitatives obtenues à partir de méta-analyses publiées et de notre niveau de compréhension actuel, nous concluons que l'atténuation du climat induite par un stockage accru du SOC est généralement surestimée si l'on ne tient pas compte des émissions de N$_2$O associées, mais, à l'exception du travail réduit du sol, n'est jamais totalement compensée. Certaines options (par exemple, le biochar ou l'application d'un amendement C non pyrogène) peuvent même réduire les émissions de N$_2$O.

International audience; The microscale physical characteristics of microbial habitats considerably affect the decomposition of organic matter in soils. One of the challenges is to identify microheterogeneities in soil that can explain the extent of carbon mineralization. The aim of this study was therefore to identify descriptors of mu m-scale soil heterogeneity that can explain CO2 fluxes obtained at the mm scale. A suite of methods and models that visualize soil heterogeneity at scales relevant to microorganisms has been developed over the last decade. Among the existing 3D models that simulate microbial activity in soils, Mosaic is able to simulate, within a short computation time, the microbial degradation of organic matter at the microhabitat scale in soil using real 3D images of soil porosity. Our approach was to generate scenarios of carbon mineralization for various microscale environmental conditions and determine how the descriptors of soil structure could explain CO2 evolution. First, we verified that the simulated diffusion of solutes in the soil samples obtained with Mosaic were the same as those obtained using the same parameter set from a robust 3D model based on a lattice Boltzmann approach. Then, we ran scenarios considering different soil pore architectures, water saturations and microorganism and organic matter placements. We found that the CO2 emissions simulated for the different scenarios could be explained by the distance between microorganisms and organic matter, the diffusion of the substrate and the concentration of the available substrate. For some of the scenarios, we proposed a descriptor of accessibility based on the geodesic distance between microorganisms and organic matter weighted by the amount of organic matter. This microscale descriptor is correlated to the simulated CO2 flux with a correlation coefficient of 0.69. Highlights Does the microscopic soil organisation explain the macroscopic mineralisation fluxes ? We present a new descriptor based on the geodesic distances between organic matter and microorganisms. We found a correlation between the descriptor of mu m-heterogeneity and the mineralization fluxes. Other scenarios should be carried out under wider environmental mu m-conditions to confirm our results.

International audience; Understanding the processes underlying carbon (C) stability in soils is of utmost importance in the context of climate change. In this setting, biochar is often studied for its persistence in soils and reported to have positive impacts on soil fertility. Whilst recent research has mostly focused on the short-term effects of biochar amendments to soil, a better understanding of its long-term persistence in soils is needed. Our study focuses on agricultural soils enriched in charcoal residues, produced in preindustrial kiln sites ca. 220 years ago, as a proxy for aged biochar. Our aim is to better understand the processes governing the long-term persistence of pyrogenic organic matter (PyOM) in cultivated soils. To achieve this, we focus on i) the effect of PyOM on soil aggregation, ii) its distribution amongst soil fractions and iii) its chemical and thermal properties. For this purpose, we combined a soil particle size-density fractionation with elemental and thermal analyses on topsoil samples collected in charcoal enriched (CHAR) and adjacent reference (REF) soils in a conventionally cropped field in Wallonia (Belgium). The presence of charcoal in soils resulted in a 91 ± 34% higher C content in CHAR soils than REF soils, of which 84 to 94% was PyOM and 6 to 16% was additional non-PyOM. In CHAR soils, macroaggregation was promoted at the expense of microaggregation (CHARMACRO = 48.9 ± 12.8; CHARMICRO = 25.5 ± 8.3 g 100 g−1 soil) whereas these were similar in REF soils (REFMACRO = 41.3 ± 9.5; REFMICRO = 36.0 ± 8.7 g 100 g−1 soil). Elemental and thermal analyses revealed that PyOM did not only occur as free light fractions but was also occluded in aggregates or sorbed onto mineral phases (56.4 ± 22.9% of total PyOM) suggesting PyOM may be further stabilized through organo-mineral associations. Century-old PyOM showed increased H:C and O:C atomic ratios compared to recently pyrolyzed OM, particularly in occluded as opposed to free light fractions, vouching for the functionalization of its surfaces. Furthermore, regardless of high C contents in CHAR soils, similar C:N ratios between studied soils in mineral dominated fractions suggested increased amounts of N-rich non-PyOM in charcoal rich soils. Our results demonstrate that, over centuries in cultivated soils, PyOM plays an active role in aggregation patterns. We conclude that century old PyOM is broken down from coarse to fine particles, and through functionalization of its surfaces contributes to organo-mineral associations. Beyond its intrinsic chemical recalcitrance, the long-term persistence of biochar is enhanced by occlusion and sorption processes.

International audience; L’initiative « 4 pour 1 000 : les sols pour la sécurité alimentaire et le climat » propose d’augmenter chaque année d’un quatre millième le stock de carbone présent dans tous les sols du monde. À la demande de l’Ademe et du ministère de l’Agriculture et de l’Alimentation, l’Inra (devenu aujourd’hui INRAE) a conduit une étude, centrée sur la France métropolitaine, visant à estimer le potentiel de stockage de carbone des sols agricoles et forestiers et, in fine, à mesurer la contribution potentielle de ce levier à l’objectif de réduction des émissions nettes de gaz à effet de serre. Diverses pratiques candidates (cultures intermédiaires, apport de nouvelles ressources organiques, gestion des prairies, agroforesterie …) ont été évaluées. Les résultats obtenus ont montré une forte variabilité du stockage additionnel de carbone. L’étude a également permis d’estimer le coût supplémentaire, pour les agriculteurs, de mise en œuvre de ces pratiques de stockage, puis une allocation de l’effort de stockage entre les pratiques et les régions a été effectuée. Ces données permettront aux différents acteurs concernés de faire les meilleurs choix pour stocker davantage de carbone dans les sols. Cet ouvrage s’adresse aux décideurs chargés de l’élaboration des politiques publiques climatiques dans le domaine agricole, aux responsables territoriaux, aux aménageurs, aux ingénieurs et techniciens, aux agriculteurs et à l’ensemble des citoyens intéressés par la problématique de l’agriculture et du changement climatique.

Introduction: Parkinson’s disease (PD) is a neurological disorder that affects the dopamine-producing neurons and affects the patient’s movements. According to the World Health Organization, about 1% of the world’s population aged 65 years or older has PD. The study aims to analyze the hospitalizations for Parkinson’s disease in Brazil and highlight the importance of primary health care (PHC) in the care of these patients. Methods: This is an integrative literature review, using articles from the Pubmed and Medline databases, as well as the DATASUS database from January 2017 to January 2021. The descriptors used were: “Parkinson’s Disease”; “Comprehensive Health Care”; “Patient-Centered Care”. Results: In the period analyzed there were 3.536 hospitalizations for PD in Brazil with spending of R$14,937,372.3 highlighting the Southeast region that represents 49% of the total of these. Regarding sex, age and self-reported color/race, the most affected are men with 60.6%, individuals between 60 and 69 years (26.3%) and whites (49.9%). A total of 218 deaths were registered, with a mortality rate of 6.1%. Discussion: The PHC is responsible for part of the diagnosis and monitoring of patients with PD, being a central part in the coordination of care. It acts through the levels of care and improves the quality of life of its users through health actions, thus improving their quality of life. Conclusion: Basic health units must improve themselves through the continuous training of the professionals involved, thus resulting in a decrease in the mortality rate.