Dissolved organic matter (DOM) fraction of four soils with different vegetation types (grassland, spruce, oak, agricultural) were incubated at 15 °C and the chemical changes of organic matter were monitored by synchronous fluorescence and 2D-correlation spectroscopy. Fluorescence spectroscopy revealed that at the beginning of incubation, on day 3, the proportion of low molecular weight readily biodegradable compounds increases, and from day 8 onwards, the initiated microbial degradation generates a large number of medium molecular weight molecules. At further samplings (days 21, 35 and 60), the proportion of compounds of microbial origin decreases systematically, due to a decrease in microbial activity caused by the lack of substrate. In 2D correlation measurements, we found that the temporal change in spectral ranges was as follows: 250 → 290 → 360 nm. This provides spectroscopic evidence that microorganisms start to consume low molecular weight peptide or sugar-like substances and then release organic matter into the environment through their death and metabolism. At a later stage of incubation, they start to break down the higher molecular weight fulvic acid-like molecules.

We concluded that (i) similar patterns emerged in the spectral features of degradation for the four different soils: the dynamics of organic molecules with different size ranges were the same, (ii) a general scheme was found during the decomposition: microorganisms begin to break down the low-molecular-weight organic substances, and then, through their death and metabolism, release organic substances into their environment; finally, in the later stages of mineralization, the higher molecular weight, fulvic acid-like molecules are degraded and (iii) 2D-correlation spectroscopy has proven to be an effective tool for monitoring chemical changes in dissolved organic matter, revealing both simultaneous and sequential chemical events.

This work was supported by the Development and Innovation Fund of Hungary [grant No. NKFIH 132191].

How to cite: Filep, T., Zacháry, D., Ringer, M., Jakab, G., and Szalai, Z.: Investigation of the decay of DOM fraction in soils with different vegetation types by fluorescence and 2D-correlation spectroscopy, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-5437, https://doi.org/10.5194/egusphere-egu23-5437, 2023.

The different environmental conditions (temperature, oxygen and water availabilities), microbial composition, availability of fresh organic inputs and textural and mineralogical properties of soil layers with the depth result differences between the origin, composition, C/N ratio and stability of the dissolved organic matter (DOM) of topsoils and subsoils.

This research examines the content and chemical composition of the DOM of topsoil and subsoil layers of a silty Luvisol and a sandy Arenosol. Both soils are derived from oak forests from Hungary. The soils were collected as composite samples (10 random subsamples within a 20 m × 20 m area) from the 0–20 and 30–50 cm layers.

The DOM was extracted with ultrapure water for 12 h at room temperature with a tumbling shaker. The sample was centrifuged for 35 min (1400 × g) and the supernatant was decanted and passed through a 250 µm-sieve. The fraction that passed through the sieve was filtrated through a 0.45 μm membrane filter to obtain the DOM samples. The filtered samples were acidified to pH 2 with HCl, passed through a solid phase extraction cartridge using a styrene divinyl benzene polymer sorbent (Agilent Mega Bond Elut PPL), eluted with methanol and dried.

The dried DOM samples were analyzed with a Bruker Vertex 70 FT-IR spectrometer. For each sample a spectral range of 4000–400 cm^–1, a resolution of 4 cm^–1, 128 scans, and three replicates were recorded. Relative absorbances were calculated for six peaks (2920, 2850, 1730, 1640, 1515, or 1420 cm^–1) representing characteristic organic matter compounds.

The dried DOM samples were dissolved in 0.05 M NaHCO₃ solution in order to determine the C and N content and the fluorescence and UV-VIS-NIR spectroscopical properties. The total organic carbon and nitrogen content of the DOM samples were analysed using a TOC/TN analyser (Shimadzu TOC-L). The chemical composition of the DOM samples was determined using fluorescence (Shimadzu RF6000) and UV-VIS-NIR (Shimadzu UV3600) spectrometry. Excitation-emission matrices were obtained by measuring fluorescence intensity excitation wavelengths ranging from 230–450 nm and emission wavelengths ranging from 260–600 nm with 2 nm increments. Fluorescence, humification and biological indices were determined from the fluorescence spectra in order to determine the sources, structural complexity and humification degree of the DOM samples. Synchronous fluorescence spectra were recorded with a fixed wavelength difference (Δλ=18) to separate SOM components with different molecular weights. Specific UV absorption (SUVA₂₅₄ and SUVA₂₈₀, L mg^-1 m^-1) was calculated by dividing the absorption at 254 and 280 nm by the DOC concentration.

The study aimed to assess the differences between the sources and the structural and chemical variability of the DOM samples from varying soil depths with different textural properties.

This work was supported by the Development and Innovation Fund of Hungary [grant No. NKFIH 142936] and the Eötvös Loránd Research Network [grant No. SA41/2021].

How to cite: Zacháry, D., Filep, T., Sziklai, Á., Király, C., Jakab, G., Ringer, M., and Szalai, Z.: Origin and chemical composition of DOM fractions from topsoil and subsoil layers of a silty and a sandy forest soil using FT-IR and fluorescence spectroscopy, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-6965, https://doi.org/10.5194/egusphere-egu23-6965, 2023.

Agriculture is a massive production with intensive practices, like large variety of agro-chemicals, heavy machinery etc., that support food security. However, recently more and more attention is given to food safety in relation to human, environment and soil health. An alternative strategy is organic agriculture that avoids the use of synthetic chemicals and maintain the sustainable food production. But organic farming cannot completely support the worlds foods demand, so adaptation is needed to reach a sustainable productivity while protecting the environment.

Soil nitrogen (N) pool consists of inorganic and organic fractions. Inorganic and a part of labile organic N is a primary nutrient source for plants and microbes. Different nitrogen fractions play various roles in soil ecosystems and can be strongly influenced by the site management. Soil nitrogen transformations are directly relatable to plant health, thus strongly influence healthy functioning of soil ecosystem. Knowledge about the soil nitrogen pools is necessary to assess the proper and sustainable fertilization approaches under various management practices. To evaluate various N fractions, fresh soil samples were sampled (20 cm depth, row and near tree) at 8 conventional and 8 organic apple farms (Germany: states of Brandenburg, Saxsony and Saxony-Anhalt), with various age, locations and management practices. Soil samples were analyzed using CNS, Kjeldhal digestion, spectrophotometer and chloroform fumigation. The aim of this study is to compare the total and labile (particulate organic, microbial biomass and water extractable organic) N fractions in soil samples considering various site management approaches, topography and climate.

How to cite: Sut-Lohmann, M., Grimm, M., Heinrich, M., Baig, S., and Raab, T.: Soil nitrogen pool and its fractions in German apple orchards under organic vs conventional management, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-3208, https://doi.org/10.5194/egusphere-egu23-3208, 2023.

In the framework of the EU Green Deal, the reduction of chemical fertilization is promoted to enhance sustainable agriculture. An ecological option is to utilize the potential of soil microorganisms to improve plant growth and secure crop production. Past studies focused mainly on Rhizobia and their specific plant-growth promoting effects on target plant hosts (N-fixing). Recently, Lactobacilli (Firmicutes) gained increasing appreciation as soil nutrient regulators, besides their known plant protecting properties, for a broad range of plant hosts.

In this pot experiment, we studied the short-term effects of a Lactobacillus soil inoculant (LB) on tomato plants (Solanum lycopersicum L. var. extasi) and nitrogen kinetics, in two different soils (sandy (S), loamy (L)), with chemical (U; urea; 460 N mg/kg) and organic (DC; digestate compost; 22 g/kg) treatment. An unfertilized control (C) treatment for each soil was also included. The experiment lasted 115 days and two experimental setups run in parallel; soil containers a) without and b) with plants. During the experiment soil concentrations of NH₄+, NO₃-, NO₂-, CO₂ and N₂O were measured. At the end of the experiment, additional agronomic traits (total biomass, total N) and soil N mineralization potential (AMN) were measured. 

The addition of LB in C and DC treatments increased soil NH₄+ that ranged 1.5 – 28% relative to the treatments without LB, for both soils. When LB was added in the U treatment we observed a negative effect, -3% and -54% for L and S soil, respectively. A contradicting pattern was observed for soil NO₃-, when LB was added in all treatments, soil NO3- increased and decreased in L and S soil, respectively. Soil NO₂-, CO₂ and N₂O emissions increased in DC and U treatments for both soils, relative to C. Interestingly, when LB was added we observed a consistent decrease in soil NO₂- and N₂O emissions but a consistent increase in CO₂ emissions for both soils was observed, relative to those treatments without LB. The addition of LB had a positive effect on plant biomass and total plant N for all treatments and for both soils, except U+LB treatment in S soil. As for AMN rates, there was not a consistent pattern.

In conclusion, our preliminary results indicate a positive effect of non-N-fixing lactobacilli inoculant on plant attributes for soils amended with compost. Furthermore, we documented a microbial approach to mitigate potential N₂O emissions from organic amendments for the first time.

The BSc research work by Katerina Bouzaki was partly supported by the Hellenic Foundation for Research and Innovation (H.F.R.I.) under the 2nd Call for H.F.R.I. Postdoctoral Research Projects (#1053) awarded to Principal Investigator Dr. Georgios Giannopoulos.

This project was co-implemented with industrial partner Corteva Agriscience Hellas SA.     

How to cite: Bouzaki, A. (., Elsgaard, L., Menexes, G., Zanakis, G., and Giannopoulos, G.: Effects of Lactobacilli inoculum on tomato plants, soil nitrogen transformations and greenhouse gass emissions., EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-9903, https://doi.org/10.5194/egusphere-egu23-9903, 2023.

Nitrogen (N) availability is one of the critical limiting factors regulating plant growth, microbial activity, and the interactions between plants and soil microorganisms. The competition between plants and microorganisms, represented by the ratio of microbial N immobilization and plant N uptake (measured as Nim: PNU ratio), generally reflects the degree of N limitation in a terrestrial ecosystem. However, the key factors driving the pattern of Nim: PNU ratio across global ecosystems remain little understood. Here, using a global data set of 1022 observations from 184 studies, we examined the relative importance of mycorrhizal associations, N availability, climate, plant, and soil properties on the Nim: PNU ratio. Our results show that mycorrhizal fungi type (arbuscular mycorrhizal (AM) vs. ectomycorrhizal (EM) fungi) in combination with soil N availability explain the variation in the Nim: PNU across terrestrial ecosystems. In AM fungi-associated ecosystems, the relation between Nim and PNU displayed a weaker negative correlation (r =-0.06, p < 0.001), whereas there was a stronger positive correlation (r = 0.25, p < 0.001) in EM fungi-associated ecosystems. Those results indicated that the AM-associated plants display a weak interaction with soil microorganisms for N absorption, while EM-associated plants cooperate with soil microorganisms. Further, we found that the Nim: PNU ratio for both AM- and EM-associated ecosystems gradually converge at a stable value (14.7 vs. 13.5, p > 0.05) with greater N availability. Our study thus highlights that plant-microbial interaction for N absorption both equalize and stabilize at increased N supply, and both these mechanisms primarily depend on the mycorrhizal association of plants in terrestrial ecosystems.

How to cite: Du, Z. and Zhou, X.: Plant-microbial interactions for nitrogen absorption converge between arbuscular- and ectomycorrhizal-dominated ecosystems at high nitrogen availability, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-4095, https://doi.org/10.5194/egusphere-egu23-4095, 2023.

Phosphorus (P) is limiting plant nutrient in natural and agriculturally used soils. P is presented in soil composition of various inorganic (mineral) and organic compounds.  Organic P compounds are very strongly adsorbed on the mineral surfaces and are therefore not available to the plants. Desorption of P from mineral surfaces into soil solution would be more limited for organic P compounds compared to inorganic P compounds. It is suggested that organic P availability is limited mainly by the solubility of organic P compounds. Due to very few works on soil organic P there is not enough information about potential contribution to P availability in the soil–plant system.
The goal of this research was to investigate the correlation between soil organic phosphorus and fraction of organic phosphorus extracted by Mehlich 3 method. Also the impact of soil pH, organic carbon content and texture to this correlation is under interest. 

How to cite: Tõnutare, T., Tõnutare, T., Kõlli, R., Krebstein, K., and Vennik, K.: Organic P in soil and its extraction by Mehlich 3 method., EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-10043, https://doi.org/10.5194/egusphere-egu23-10043, 2023.

During the last century multiple methods have been developed for the determination of the amount of plant available nutrient elements in the soil. One of the critical nutrient elements in soil is phosphorus. Most of the phosphorus exists in soil in the form of insoluble inorganic and organic compounds. Therefore the amount of plant available P is limited as soluble P. The goal in the development of methods is to find an extraction solution, which can extract the nutrients from soil in a similar amount as plant roots. Due to large variations in soil properties and plants abilities it is a very complicated task. 
Several methods for determination of plant available P in soils are P specific (Bray P1, Olsen, CAL). Many methods are developed using the same extractant for two (DL, Joret-Hebert) and three (AL, AAC-EDTA) element extraction simultaneously. To minimize the time of analysis and laboratory costs the focus of the research is directed to the development of multielement methods, which is usable for macro and micro nutrients analysis from the same extract.
One widely used multielement method is Mehlich 3, developed in 1983. This method is useful for determination of macro elements (P, K, Ca, Mg) and microelements (Zn, Fe, Cu, Mn, B) in soil. As used extractant (0,2M CH₃COOH, 0,25M NH₄NO₃, 0,015M NH₄F, 0,013M HNO₃, 0,001M EDTA) consists of nitrate (NO₃^-) ions, this method can not be  used to determine nitrate in soil. The modified multielement method was proposed by Yanai et al. in 2000, where the composition of the extraction solution is: 0,2M CH₃COOH, 0,25M NH₄Cl, 0,005M citric acid, and 0,05M HCl. As there are no nitrate ions in the composition of the solution, it could be used beside macro and micro nutrient elements also for nitrate content determination in soils. 
In our research soil sample sets with different pH, texture and carbon content were analyzed by Mehlich 3 and modified Mehlich 3 method. Correlations of analyzed P contents between methods and impact of soil properties to the correlations were investigated. 

How to cite: Tonutare, T., Tõnutare, T., Kõlli, R., Krebstein, K., and Vennik, K.: Soil phosphorus content determined by Mehlich 3 and modified Mehlich 3 methods, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-4568, https://doi.org/10.5194/egusphere-egu23-4568, 2023.

The regulation of N and P input on microbial communities is related to the bottom-up effects of soil resources (i.e., nutrients), and the top-down effects of predators (i.e., protists). However, it is not clear how exogenous N, P, and NP inputs effect on the bottom-up (pH, soil nutrients, and eco-stoichiometry ratio of C: N: P), and top-down (abundance and diversity of protist community) factors to estimate soil microbial community involved in C-, N-, and P- mineralization. In this study, we explored the effects of a 7-years N, P, and NP inputs on the bottom-up and top-down controls on the abundance and diversity of functional microbial communities in the subtropical Chinese fir plantations using metagenomic sequencing. The results showed that N and NP inputs decreased soil pH and soil acidifying cause a reduction in the alpha diversity of microbial function. Exacerbated soil microbial C limitation under N, P, and NP inputs was negatively correlated with the alpha diversity of metagenomic function. The alpha diversity of bacteria was negatively correlated with the ratios of soil total and available N: P, due to increasing available P content. Regarding top-down effects of protists on the abundance and diversity of microbial C-, N-, and P- mineralization community, P and NP inputs increased alpha diversity of protist, thus, selectively increased the relative abundances of Calditrichaeota involved in C-mineralization, and decreased the relative abundances of Elusimicrobia and Marinimicrobia involved in N-mineralization. Although protozoa feed on both bacteria and fungi, changes in protists under N, P, and NP inputs mainly affected bacterial diversity and abundance, with no significant changes in fungi. Overall, the present results provide important knowledge on bottom-up (pH, soil nutrients, and eco-stoichiometry ratio of C: N: P), and top-down (abundance and diversity of protist community) factors of the abundance and diversity of the microbial community involved in C, N and P mineralization in the context of elevated N and P input.

How to cite: Liu, S., Zhang, X., Wang, H., Pan, J., Tang, Y., and Chen, F.: Effects of nitrogen and phosphorus inputs on the diversity of carbon-, nitrogen-, and phosphorus- mineralization microbial communities in subtropical Chinese fir plantations, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-2731, https://doi.org/10.5194/egusphere-egu23-2731, 2023.

The impacts of land use on organic carbon (OC) and nitrogen (N) in different ecosystems have been widely studied. However, less attention has been paid to its influence on the change of total phosphorus (P_t) and its two fractions, inorganic P (P_i) and organic P (P_o), along slopes. In addition, since N and P are the main factors causing the eutrophication of aquatic ecosystems, it is essential to link the terrestrial and aquatic ecosystems.

Two slope-floodplain-creek catenas were chosen in the low mountain region of the eastern Bavarian Forest. The slopes of the two catenas have been extensively managed for grassland and cropland use, respectively. The floodplain was under grassland use. They were fertilized with sludge, occasionally with farmyard manure, under the same regime. Additional carbonic magnesium lime was applied annually at the cropland. Soil profiles at the top, middle and bottom slope, as well as the floodplain area, were sampled according to their horizons and replicated with three soil cores in each catena. Liquid-nitrogen freeze-cores of the aquatic sediments were sampled to extend each catena into the below-slope creek.

We found the grassland slope had higher OC and N content in the topsoil (0-10 cm) and higher P_t and P_o content in both the topsoil (0-40 cm) and subsoil (40-60 cm). The P content in the topsoil (0-40cm) of the grassland slope was dominated by P_o, while the cropland slope was P_i -dominated. The OC and N stocks on the grassland slope were significantly higher than at the corresponding position on the cropland slope. Except for the lowest P stock found on the top slope of grassland, the P_t stock in topsoil (0-20 cm) was not land-use affected while the P_o stock was significantly higher on the grassland slope. An accumulation of OC, N and P_o in topsoil (0-20 cm) from top to bottom of the slope was observed. In the floodplain, upslope cropland use decreased the OC, N, P_t content and stocks, but reversely for P_o. The upslope land use effect on OC, N and P content in the creek sediment was limited.

In conclusion, this study provides a field-based observation on the change of OC, N and P (P_t and P_o) under different land use upslope from terrestrial to aquatic systems through two slope-floodplain-creek catenas.

How to cite: Lei, K., Bucka, F., van Grinsven, S., Völkel, J., and Kögel-Knabner, I.: Changes in soil carbon, nitrogen, phosphorus along two temperate slope-floodplain-creek catenas under different land use - A case study in Southeast Germany, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-1544, https://doi.org/10.5194/egusphere-egu23-1544, 2023.

Dissolved organic matter (DOM), the most active functional component of soil organic matter (SOM), plays a vital role in regulating soil biogeochemical processes and accumulation and decomposition of SOM and their responses to global change. Although the quantity and fluxes of soil DOM has been inventoried across diverse spatio-temporal scales, the underlying mechanisms accounting for the variability in DOM dynamics remain unclear especially in upland ecosystems.

Mollisols is famous for its high fertility and is vital for global crop production. Northeast China is one of the three Mollisols regions in the world, contributing to 1/4 of Chinese grain production. However, a loss of SOM has occurred in this area over the past decades, both in its content and activity. Understanding the processes involved in DOM transformations is of critical importance for SOM management. Here, a gradient of SOM storage across twelve Mollisols uplands with various cultivation years in northeast China were used to understand links between DOM dynamics, microbial metabolism, and abiotic conditions. We assessed the composition, biodegradability and key biodegradable components of DOM. In addition, SOM and mineral-associated organic matter (MAOM) composition, soil enzyme activities, oxygen availability, soil texture, and iron (Fe), Fe-bound organic matter and nutrient concentrations were quantified to clarify the drivers of DOM quality.

Changes in concentrations of DOM and SOM were tightly coupled across various croplands. The proportion of biodegradable DOM increased exponentially with decreasing DOM concentration. Spectral analyses showed that larger fractions of small-molecular phenols and proteinaceous components mainly contributed to the greater biodegradability of DOM. Unexpectedly, the composition of DOM was decoupled from that of SOM or MAOM, but significantly related to enzymatic properties. Further analyses indicated that soil oxygen availability exhibited a dominant role in DOM generation. As DOM concentration declined, increased soil oxygen availability regulated DOM composition and enhanced its biodegradability mainly through three ways: 1) stimulated oxidase-catalyzed depolymerization of humic substances into small aromatic molecules; 2) promoted production of protein-like DOM components due to lower enzymatic C/N acquisition ratio; and 3) oxygen-induced oxidation of Fe(II) to Fe(III) removed complex DOM compounds with large molecular weight. Therefore, along with aggregates fragmentation during the decline of SOM in Mollisols with longer cultivation history, the increased oxygen availability improved the biodegradability of DOM and accelerated the turnover and loss of active SOM pool.

Overall, this study demonstrated the cascading effects of oxygen on soil Fe oxidation-reduction, microbial metabolism and the dynamics of DOM, which would help understand the processes of labile SOM transformations and interactions among various drivers and improve the SOM managements in upland ecosystems and the predictions of responses of soil carbon to climate change.

How to cite: Chen, Z., Li, Y., and Ding, W.: Oxygen availability regulates the persistence of soil dissolved organic matter by mediating microbial metabolism and iron oxidation, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-4294, https://doi.org/10.5194/egusphere-egu23-4294, 2023.

Alternate wetting and drying (AWD) is considered as an effective water-saving practice for rice cultivation widely applied across the world. Although AWD can reduce global warming potential compared to continuous flooding (CF), it may have negative effects on N availability for crop by promoting N losses (nitrification-denitrification, leaching) and immobilization, due to the frequent soil redox cycling. By means of a growth chamber pot experiment and a ¹⁵N stable isotope approach we investigated the interactions between water, crop residue and fertilizer N management on the contribution of different N sources (i.e. fertilizer, rice straw, soil) to rice plant N uptake. We hypothesized that with respect to CF, AWD will decrease plant uptake of fertilizer (FDN), straw (StDN), and soil (SDN) derived N due to greater losses, greater microbial N immobilization during residue turnover under oxic conditions, and less N supply from soil organic matter (OM) desorbed under reducing conditions. Moreover, we hypothesized that the underlying processes will be influence by the timing of straw addition with respect to flooding and the temporal distribution of mineral N application.

Rice was grown for 60 d in a factorial setup including: (i) two water regimes: CF for 60 d vs. AWD (30 d of flooding followed by 30 d of alternating conditions involving 3 drain-flood cycles), and (ii) three straw and fertilizer managements that involved a combination of straw addition (10 Mg ha^-1) 30 or 60 d before seeding (S30 and S60, respectively), and N fertilization (ammonium sulfate) split between pre-seeding and tillering in 60+60 or 80+40 kg N ha^-1, such that treatments compared were S30-N60-N60, S30-N80-N40 and S60-N60‑N60. ¹⁵N-enriched fertilizer and straw were used in separate replicated setups to quantify the relative contribution of FDN, StDN and SDN to plant N uptake, as well as fertilizer use efficiency (FUE).

Plant N was mainly soil and fertilizer-derived (≈ 58 and 40%, respectively), while straw only contribute a minor amount (< 3%). Although AWD reduced total N uptake by about 10-13% with respect to CF, FDN and FUE were only slightly affected by water management, suggesting that differences in N nutrition did not depend exclusively on fertilizer N losses. SDN contributed more to plant nutrition in CF than in AWD, particularly when straw was incorporated in proximity to flooding. The combination of a fresh OM supply and reducing conditions under CF favoured the reductive dissolution of Fe oxides and desorption of soil OM that increase soil N supply via mineralization. StDN contributed less to plant nutrition in AWD than in CF albeit the higher mineralization rates we expected with more frequent oxic conditions. We attributed this to a higher microbial N demand under aerobic conditions that leads to a greater immobilization SDN during decomposition. The higher SDN and StDn for N60-N60 treatment with respect to N80-N40 suggested that an equilibrated splitting of N fertilizer between pre‑seeding and tillering stages could favor microbial activity under AWD improving straw degradation and soil N release.

This research was funded by the Lombardy Region through the project RISWAGEST

How to cite: Vitali, A., Russo, F., Vidotto, F., Miniotti, E. F., Celi, L., Romani, M., and Pullicino, D. S.: Interaction between water, crop residue and fertilization management on the source-differentiated nitrogen uptake by rice, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-17165, https://doi.org/10.5194/egusphere-egu23-17165, 2023.