SSS2.4

Flooding affects >300 million people each year and causes loss of life, damage to infrastructure, and long-term mental and physical health problems. Across many parts of the globe, climate change is projected to increase the magnitude, frequency, and intensity of rainfall events, thus exacerbating future flood risk and increasing the demand for flood alleviation schemes. Agricultural land covers 39% of Europe, and as such intercepts a significant fraction of precipitation. Agricultural intensification has increased soil compaction and decreased soil porosity and permeability, thus decreasing infiltration, storage and groundwater recharge. Here, we report on experiments that aim to constrain the effects of using cover crops to increase soil porosity and permeability and hence decrease runoff during rainfall events in three arable fields in East Yorkshire, UK.

Half of each field was treated with a cover crop between harvest and winter cultivation, and the organic matter of this crop was incorporated into the soil. The second half of each field was used as a control. A suite of methodologies is being used to assess the long-term influence of this extra organic matter content on soil structure, health and permeability:

• An array of soil moisture loggers (Delta-T PR2/4, DalesLandNet MKII, GroPoint Profile 2625-N-T-4) was deployed in each field to provide long term soil moisture data at high temporal resolution;
• Roaming soil moisture measurements (Campbell Scientific HydroSense II) were used to increase spatial coverage and resolution;
• Laboratory measurements of soil density, ambient soil moisture content, porosity, permeability, and nutrient content (nitrogen, phosphorous and potassium); and
• A 3D MODFLOW model parameterised with collected data was used to assess the long term impact of increased soil porosity and permeability on rainfall transmission in to surface water drainage systems.

Preliminary results suggest that enhanced organic matter – delivered through cover crops – increases soil nutrient and moisture retention and decreases the peak flow stage in adjacent drainage channels after intense rainfall events. These observations suggest soil restoration may provide an important mechanism for attenuating flood peaks under future climate scenarios.

How to cite: Thomas, R., Ahmed, J., and Johnson, J.: Cover crops as a method of enhancing soil moisture and nutrient retention on arable farmland, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-13528, https://doi.org/10.5194/egusphere-egu22-13528, 2022.

As previously foreseen, it seems like climate change effects have begun to take their toll on the environment globally, but especially in the Eastern Mediterranean-Middle East (EMME) region where a hot climate already prevails. Some of these effects include higher temperatures during summer season, greater heat stress, longer summers, lower soil moisture, greater water scarcity, more intense rainstorms, longer duration between rainstorms, reduced air quality due to greater pollution and more. Rainfall temperature is also a variable that potentially will be affected by changes in climate regime.

These alterations in climate regime might play an even greater role in soil erosion which has already become a concern on a global scale due to its impairing effects on human activity. Although, soil erosion variables have been studied extensively on various levels, very little has been researched on the effects of rainfall temperature on the soil. A few years ago, comparative research with a laboratory rainfall simulator was conducted on two soils, a clayey soil and loamy soil from Israel, in dry and wet conditions, under different rainfall temperature regimes. The researchers concluded that rainfall temperature has an impressionable effect on runoff and soil erosion that must not be ignored, and which is more pronounced in the clayey soil. Recently, and in accordance with these findings, follow-up research was conducted on two pre-wetted clayey soils, 43% and 64% clay content, respectively. The Terra Rosa soils were chosen from different locations in Israel and are similar to each other in salt concentration, organic matter content and land use (plots between olive trees in an olive grove), yet are different from one another in clay content, and possibly in clay-mineral type as well. The soils were pre-wetted and allowed to drain to field capacity state, and then were exposed to 21 mm/hr rainfall events at 3 different temperatures: 2, 20 and 35 degrees Celsius, respectively. Runoff and soil samples were collected throughout the experiments. Temperature was monitored at water tank, nozzle, soil surface and soil subsurface with thermocouples and a thermal camera. Each experiment was repeated 4 times on 2 different soils with 3 different temperatures, rendering a total of 24 experiments.

In this presentation, I will demonstrate our theory for the potential of rainfall temperature as an important variable on soil erosion and will present our initial findings based on our recent experiments.

How to cite: Shkedi, D., Sachs, E., and Pariente, S.: Effect of rainfall temperature on the erosion of clayey soils different in clay amount: experiments with a laboratory rainfall simulator, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-10427, https://doi.org/10.5194/egusphere-egu22-10427, 2022.

The Don River Delta is a unique natural structure that performs an important ecological function as a spawning ground for endangered fish species. Shipping is a source of carcinogens of the group of polycyclic aromatic hydrocarbons (PAHs), including benzo(a)pyrene (BaP) - substances of the 1st hazard class. The maximum permissible concentration (MPC) of BaP in the soil is 20 μg / kg. The accumulation of PAHs in the floodplain soils of the delta is especially dangerous since the active washout of pollutants with the soil mass during the flood period (spring) coincides with fish spawning.

The object of the study was saturated alluvial meadow soils. Soil properties vary within the following ranges: pH - 7.3-7.5, organic carbon content - 1.2-2.0%, physical clay - 14.9-19.4%, silt - 4.9-8.9 %. Sampling was carried out to a depth of 0-20 cm. PAHs were extracted from the soil with hexane. Quantitative analysis of PAHs in the extract was carried out using an Agilent 1260 chromatograph. In this work, the content of 16 PAHs included in the list of priority pollutants of the US EPA was determined: naphthalene, anthracene, acenaphthene, acenaphthylene, phenanthrene, fluorene, fluoranthene, pyrene, chrysene, benzo(a)anthracene, BaP, benzo(b)- and benzo(k)fluoranthene, dibenzo(ah)anthracene, benzo(g,h,i)perylene, indeno(1,2,3-cd)pyrene.

This study presents the main patterns of PAHs accumulation in the floodplain soils of the Don River delta used by the shipping channel. The purpose of the study was to establish the influence of the technogenic factor on the accumulation of PAHs in the floodplain soils of the Don River delta. As a result of the study, it was found that, according to the content of PAHs, the soils form the following row: No. 1 - 400 μg / kg> No. 2 - 1729 μg / kg> No. 3 - 9376 μg / kg. A similar series is observed for the amount of BaP in the soil: No. 1 - 22 μg / kg> No. 2 - 201 μg / kg> No. 3 - 2013 μg / kg, which corresponds to an excess of MPC by 1.1, 18 and 100 times.

Thus, the PAHs content in soils increases downstream of the shipping channel. The maximum technogenic load falls on the soil of the monitoring site No. 3, located in the mixing zone of the waters of the Taganrog Bay and the delta of the Don.

The research was financially supported by the Ministry of Science and Higher Education of the Russian Federation project on the development of the Young Scientist Laboratory (no. LabNOTs-21-01AB).

How to cite: Dudnikova, T., Barbashev, A., Sushkova, S., Antonenko, E., Deryabkina, I., Shuvaev, E., Bakoeva, G., Elgendy, H., Johar, J., Bren, D., Yakovlenko, A., and Maltseva, T.: The technogenic factor of PAH accumulation in floodplain soils of the Don River Delta, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-9822, https://doi.org/10.5194/egusphere-egu22-9822, 2022.

How to cite: Mehmandoost Kotlar, A., Everaer, B., Blanchy, G., Huits, D., and Garré, S.: The potential of adaptive drainage to control salinization in Polder context, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-8643, https://doi.org/10.5194/egusphere-egu22-8643, 2022.

Carbon sequestration in agricultural soils is an important strategy to mitigate climate change which gained renewed attention in the EU soil strategy for 2030. Stimulation of soil organic carbon (SOC) sequestration can be achieved via soil management strategies. However, these strategies may stimulate greenhouse gas (GHG) emissions such as nitrous oxide (N₂O) and methane (CH₄) and cause nitrogen (N) losses via leaching. While these trade-offs can offset the intended climate change mitigation via SOC sequestration, synergistic (positive) effects of certain soil management strategies may positively affect the mitigation potential as well. Despite the major importance of these trade-offs and synergies for the selection of sustainable and climate-proof soil management strategies, knowledge on the understanding of these effects remains limited.

In the Framework of Horizon 2020 – European Joint Programme SOIL, the ∑OMMIT-project aims to investigate the trade-offs and synergies for the most relevant soil management strategies applied in European agricultural systems. A dedicated literature study was made by eight agricultural research institutes across Europe, summarizing the results of reviews, meta-analyses, reports and original articles. The most important soil management strategies were identified and grouped into four categories: tillage management, cropping systems, water management, and fertilization and organic matter (OM) inputs (crop residues, cover crop, livestock manure, slurry, compost, biochar, liming). Search criteria including literature and land use type, time-period, and geographic origin resulted in a unique selection of 110 references (31 reviews, 46 meta-analyses, and 33 original papers). Meta-data, extracted knowledge gaps, research recommendations and main conclusions were compiled in a knowledge gap review which allows for better insight in existing trade-offs and synergies and provides guidance to future research.

This review highlights that the increase of both SOC stock change and the microbial biomass C and N, as well as the reduction in N leaching are positively affected by conservation tillage, crop rotation, permanent cropping, more efficient water management as well as using fertilization and OM inputs (e.g., cover crops, organic amendments, biochar, and liming). The effects on the N₂O and CH₄ emission mitigation are dependent on the specific soil management strategy (e.g., water management, fertilization and OM inputs) and require more research to allow to define (uniform) conclusions.

In conclusion, more dedicated research is needed for the soil management strategies that simultaneously examines SOC stocks, GHG emissions, and N leaching losses. Furthermore, we identified a lack of information on the impact of pedoclimatic conditions, specifically on the longer-term, on trade-offs and synergies. A more concerted use and installation of new long-term field experiments in different pedo-climatic European regions, seems essential for a comprehensive understanding of the impact of soil management strategies at the European level. Further, since soil management strategies are often combined and their interaction may affect the trade-offs and synergies, the impact of different soil management practices should be assessed simultaneously. Overall, the review provides a unique framework to aid the (re)design of dedicated field experiments and targeted measurements as well as simulations to improve our understanding of the identified knowledge gaps.

How to cite: Maenhout, P., Di Bene, C., Cayuela, M. L., Govednik, A., Keuper, F., Mavsar, S., Mihelic, R., O'Toole, A., Schwarzmann, A., Suhadolc, M., Syp, A., and Valkama, E.: Trade-offs between soil carbon sequestration and greenhouse gas emissions, and nitrogen leaching losses: addressing knowledge gaps, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-4712, https://doi.org/10.5194/egusphere-egu22-4712, 2022.

Soil carbon sequestration in croplands has tremendous potential to help mitigate climate change; however, it is challenging to develop the optimal management practices for maximization of the sequestered carbon as well as the crop yield. We aim to develop an intelligent agricultural management system using deep reinforcement learning (RL) and large-scale soil and crop simulations. To achieve this, we build a simulator to model and simulate the complex soil-water-plant-atmosphere interaction, which will run on high-performance computing platforms. Massive simulations using such platforms allow the evaluation of the effects of various management practices under different weather and soil conditions in a timely and cost effective manner. By formulating the management decision as an RL problem, we can leverage the state-of-the-art algorithms to train management policies through extensive interactions with the simulated environment. The trained policies are expected to maximize the stored organic carbon while maximizing the crop yield in the presence of uncertain weather conditions. The whole system is tested using data of soil and crops in both mid-west of the United States and the central region of Portugal. Our study has great potential for impact on climate change and food security, two of the most significant challenges currently facing humanity.

How to cite: Kalantari, Z.: Optimization of Agricultural Management for Soil Carbon Sequestration UsingDeep Reinforcement Learning and Large-Scale Simulations, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-13307, https://doi.org/10.5194/egusphere-egu22-13307, 2022.

Leveraging soil carbon sequestration in croplands can support climate change mitigation; however, it is challenging to develop optimal management practices to maximize both sequestered carbon and crop yield. In intelligent agricultural management systems, large-scale crop models can provide an understanding of the complex soil-water-plant-atmosphere interactions and allow the evaluation of the effects of various management practices on carbon sequestration. This study aims to investigate soil carbon dynamics in maize cropland under different management practices, and discuss their potential to leverage the carbon sink capacity of agricultural soils. The Agricultural Production Systems sIMulator (APSIM) is used to investigate soil carbon dynamics in maize cropland of Baixo Mondego, an agricultural region in central mainland Portugal, under Mediterranean climate. The model was set up using soil properties retrieved from the INFOSOIL national database and run with daily climate data from 2001 to 2020 provided by local weather stations (i.e., solar radiation, maximum and minimum temperature, and rainfall). The maize yields’ records from an agricultural farm were used for model calibration (2017 - 2019) and validation (2020 - 2021). The model was then used to investigate the impact of different scenarios focusing on distinct fertilization management practices (i.e. fertilization rates, timing, and type of fertilizer) on soil carbon and crop yields. This study is part of a larger research project funded by C3.AI Digital Transformation Institute to develop an intelligent agricultural management system using deep reinforcement learning (RL) for agriculture sustainability and climate change mitigation. This project has great potential for impact on climate change and food security, two of the most significant challenges currently facing humanity.

How to cite: S.S. Ferreira, C., Kalantari, Z., Martin, N., Marcillo, G., Zhao, P., Wu, J., and Hovakimyan, N.: Agricultural Management and Soil Carbon Sequestration: the potential of APSIM model to support climate change mitigation, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-8874, https://doi.org/10.5194/egusphere-egu22-8874, 2022.

Over‑reliance and indiscriminate use of mineral fertilisers have contributed towards declining soil health. Further, mineral fertiliser production contributes close to 1% of UK’s greenhouse gas emissions. Organo-mineral fertilisers (OMFs) are currently being investigated as a more environmentally sustainable alternative to conventional mineral fertilisers as they reduce the amount of mineral fertilisers needed by combining them with organic materials that would otherwise be destined for landfill or incineration, promoting a circular economy by returning recycled nutrients to the soil. Here, we evaluated the efficacy of a novel OMF that incorporates carbon captured from gaseous point sources into their production. This product demonstrates a potential tool for combating both climate change and soil fertility by promoting soil carbon sequestration. To assess the efficacy of these new fertilisers we conducted a field experiment consisting of three batches of OMF (5, 10 and 15%N) and compared them to a conventional mineral fertiliser and an unfertilised control in two soil types with two crops (winter barley and winter wheat).

We found that all fertilisers produced significantly more yield than the control (p < 0.05) but that there was no significant or consistent difference between the fertilisers. There was no significant or consistent differences between the stimulated root growth for any treatments (p = 0.60) and the same for organic matter, microbial biomass, pH, available nutrients (N, P, K), total nutrients (N, C, P), and metals. This leads to the conclusion that organo-mineral fertilisers can perform at least as well as conventional fertiliser. Though more seasons are needed to evaluate the benefits to the soil.

How to cite: Burak, E. and Sakrabani, R.: Evaluating the efficacy of novel green fertilisers derived from combining carbon capture technology and organic waste materials , EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-9258, https://doi.org/10.5194/egusphere-egu22-9258, 2022.

Land abandonment is outstanding as one of the main causes of soil degradation in Mediterranean mid-mountains. This process is closely linked to the rural exodus that took place in the middle of the last century, that led to the activation of natural revegetation mechanisms and massive shrub encroachment. Consequently, several ecosystem disservices have been identified, such as homogenization of landscape, loss of biological and cultural diversity, decrease in water-human-consume resources, reduction of agropastoral resources and higher wildfire risk. However, the effects on soil environment are multiple and controversial. Thus, a case study in the Leza Valley (La Rioja, Spain) has been selected to analyse the effects of post-land abandonment management through shrub clearing practices in soil quality, carbon dynamics and carbon sequestration, in order to give a second chance to these marginalised areas while fighting against Global Change.

For the soil sampling, 5 land uses have been selected: control pasture, 3 shrub clearing sites of different ages; and shrubland after cropland abandonment (6 replicates at different depths, 0-40 cm, have been collected at each study site). Physico-chemical and biological properties of the soil have been analysed in the laboratory, distinguishing between basic and acid soils. Furthermore, a theoretical map of hypothetical future shrub-cleared areas and its potential to sequester carbon has been created.

Preliminary results showed  significant differences between post-land abandonment practices. Time since intervention has resulted a key factor in carbon dynamic evolution, and an increase in carbon storage and concentration with management has been recorded.

To sum up, management through shrub clearing has demonstrated to be an adequate strategy to offset carbon emissions to the atmosphere in soils of abandoned areas in the Mediterranean mid-mountains, offering socio-economic and ecological benefices while becoming an important tool against Global Change.

This research is part of the MANMOUNT project (PID2019-105983RB-100/AEI/ 10.13039/501100011033) funded by the MICINN. Melani Cortijos-López is working with an FPI contract (PRE2020-094509) from the Spanish Ministry of Economy and Competitiveness associated to the ESPAS project.

How to cite: Cortijos-López, M., Sánchez-Navarrete, P., Errea, P., Lasanta, T., and Nadal-Romero, E.: Post-land abandonment management through shrub clearing practices as a tool for enhancing soil quality and carbon storage., EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-4808, https://doi.org/10.5194/egusphere-egu22-4808, 2022.

Temperate forest ecosystems store significant amounts of organic carbon. Site conditions, species composition, and age of stands largely influenced the amount of stored carbon. International and Hungarian studies have shown that nearly half of the carbon stored in the soil in organic matter forms in forest ecosystems. The main goal was to determine the amount of carbon stored in loess soil. Our preliminary studies have shown that climatic conditions (and the forest composition determined) have a huge effect on the carbon stock of soils. To demonstrate this effect, forest stands on loess bedrock under different climatic conditions were selected for the study. Soil drilling was performed in 40 stands and soil samples were taken by 10 cm layers from 0-110 cm depth. In addition to the soil samples, we also determined the litter mass and composition of the forest stand.
Results showed that the loess soil was leached under the forest stands, so its pH was 5.8 on average (min: 3.9; max.: 8.5). Only deeper levels contained 13% CaCO₃ (min: 1.1%; max.: 37%) in the profiles. The texture of the soils was loam or clayey loam with good water holding capacity; therefore, the soil types were Luvisol and Cambisol soils. The average amount of carbon stored in the soils was 1.04 % (min.: 0.02%; max.: 7.3%)  In the future, we will try to clarify the relationship between soil organic carbon stocks and weather conditions.

Project no. 141603 has been implemented with the support provided by the Ministry of Innovation and Technology of Hungary from the National Research, Development and Innovation Fund, financed under the MEC_R_21 funding scheme.

How to cite: Bidló, A., Végh, P., and Horváth, A.: A large-scale study of the carbon stock of Hungarian forest soils, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-7762, https://doi.org/10.5194/egusphere-egu22-7762, 2022.

Soils are by definition important carbon sinks, in particular for non-tropical types of climates, an important part of carbon in ecosystems are located on them. Under climate change, those carbon sinks are placed under stress due to often-subtle changes that modify the conditions for their function and rend them particularly vulnerable to dereliction, reducing the capacity to act as carbon sinks at the long term.

In agricultural soils, the intensification of cropping systems and the reduced addition of organic matter results in a sharp reduction of soils’ organic content, with important impacts on soil functioning, namely in what concerns water and nutrient cycles, which will reduce soil fertility and carbon content on the long run. This will transfer slowly but steadily soil’s organic carbon to the atmosphere, reinforcing climate change.

Forest soils suffer an even more catastrophic impact from climate change, since the regions more vulnerable have a higher frequency and intensity of the big eraser, when the forest systems fail to be in equilibrium with the climate: forest files. They are responsible altogether by the emissions of various compounds to the atmosphere, comparable to the anthropic emissions in a bad forest fire year. The soils derelict by fire lose an important part of environmental services they provide, namely suffer a significant reduction of their capacity to sink carbon. This adds to the instantaneous loss of carbon to the atmosphere during the fire and downstream to aquatic ecosystems thereafter.

We explore methodologies to reduce those losses in wet Mediterranean areas, aiming to increase the carbon sinks to reduce the atmospheric concentrations.

How to cite: Ferreira, A.: Soil and climate interactions in the Mediterranean. Are we heading for disaster?, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-13285, https://doi.org/10.5194/egusphere-egu22-13285, 2022.

The air pollution with fine particulate matter (PM) of dimension 2.5 µm or less (PM_2.5) causes lung and other diseases. The problem of prevention of water and terrestrial systems pollution with PM dry deposits is multifaceted. The ionized O₂ is capable to intensify the atmosphere turbulence, PM_2.5 сoalescence, and increasing the PM dry deposition velocity. Unfortunately, outdated environmental technologies are incapable to secure this. The quality of air is linked to the pedosphere and plant kingdom. Addressing the problem of environmental quality, including the PM_2.5 content reduction in the atmosphere, the Biogeosystem Technique (BGT*) transcendental (nonstandard and not a direct imitation of Nature) methodology has been developed. The BGT* focus is an enrichment of the Earth's biogeochemical cycle. The heuristic approach to land use and air cleaning is a new niche for development to improve the soil system and ensure a high rate of air cleaning. BGT* ingredients are the intra-soil processing, which provides the soil multilevel architecture; intra-soil pulse continuously discrete watering for optimal soil water regime and freshwater saving up to 10-20 times; intra-soil dispersed environmentally safe recycling of the PM sediments and other pollutants; controlled microbial community and biofilm-mediated interactions in the soil. BGT* enriches the biogeochemical cycle, provides a better function of the humic substances, biological preparation and microbial biofilms as a soil-biological starter, priority plant and trees nutrition. BGT* methodology is capable to increase plant resistance to phytopathogens. BGT* provides the formation of higher underground and aboveground biological products, thus increasing reversible C biological sequestration from the atmosphere in the form of additional aboveground biomass and soil organic matter. BGT* provides a higher rate photosynthetic production of light O₂ ions, a coalescence of PM_2.5, PM_0.1 to the PM₁₀ and larger particles, sedimentation of the PM, and a soil transformation of PM sediments into the nutrients. BGT* allows sustainability of the biosphere, enables a high quality of the atmosphere, stabilizes the climate system of the Earth, and is capable to promote a green circular economy.

The research was supported by the Strategic Academic Leadership Program of the Southern Federal University ("Priority 2030").

How to cite: Fedorenko, E., Glinushkin, A., Kalinitchenko, V., Swidsinski, A., Meshalkin, V., Gudkov, S., Minkina, T., Chernenko, V., Rajput, V., Mandzhieva, S., Sushkova, S., Kashcheev, A., and Aysuvakova, T. P.: New approach to soil health management and air quality: One Earth One Life, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-9961, https://doi.org/10.5194/egusphere-egu22-9961, 2022.