Open Access
Effect of the long-term application of sewage sludge to a calcareous soil on its total and bioavailable content in trace elements, and their transfer to the crop
(MDPI, 2021-03-30) Zaragüeta, Armelle; Enrique Martín, Alberto; Virto Quecedo, Íñigo; Antón Sobejano, Rodrigo; Urmeneta Martín-Calero, Henar; Orcaray Echeverría, Luis; Ciencias; Zientziak; Institute on Innovation and Sustainable Development in Food Chain - ISFOOD; Estadística, Informática y Matemáticas; Estatistika, Informatika eta Matematika
Sewage sludge (SS) can be used as an organic amendment in agricultural soils, provided they comply with the relevant legislation. This use can incorporate traces of metals into the soil, which can cause environmental or human health problems. In the study period between 1992 and 2018 (26 years), it was observed that the use of SS as an organic fertilizer significantly increased the total concentration of Zn, Cu, Cr, Ni and Hg of this study between 55.6% (Hg) and 7.0% (Ni). The concentration of Zn, Cu, Pb, Ni and Cd extracted with DTPA, also increased between 122.2% (Zn) and 11.3% (Cd). In contrast, the Mn concentrations extracted with Diethylene Triamine Pentaacetic Acid (DTPA)were 6.5% higher in the treatments without SS. These changes in the soil had an impact on the crop, which showed a significant increase in the concentration of Zn, Cu and Cr in the grain, between 15.0% (Cr) and 4.4% (Cu), and a decrease in the concentration of Mn, Cr and Ni in the barley straw when SS was added to the soil between 32.2% (Mn) and 29.6% (Ni). However, the limits established by current legislation on soil protection and food were not exceeded. This limited transfer to the crop, is likely due to the high content of carbonates and organic matter in the soil, which limit the bioavailability of most of the trace metals (TM) in the soil. As a conclusion, we observe that the use of SS as an organic amendment increased the concentration of some TM in the soil, in its bioavailable forms, and in the crop.
Open Access
Casting activity of scherotheca gigas in no-till Mediterranean soils: role in organic matter incorporation and influence of aridity
(Hindawi / Wiley, 2010) Bescansa Miquel, Paloma; Virto Quecedo, Íñigo; Fernández Ugalde, Oihane; Imaz Gurruchaga, María José; Enrique Martín, Alberto; Ciencias del Medio Natural; Natura Ingurunearen Zientziak
The behaviour of earthworms, their role in organic matter incorporation into the soil, and the influence of aridity in such processes in arid and semiarid regions have scarcely been studied. In this study, physico-chemical analyses of the casts and the surrounding no-till agricultural soils of three experimental sites representing an aridity gradient in Navarre (NW Spain) were done. The casts were formed by the activity of the only anecic species, Scherotheca gigas (Dug`es, 1828), ubiquitous in no-till soils in this region.We observed a significant depletion of clay and higher concentration of total organic C and labile C in the form of particulate organic matter (POM) in the casts as compared to the surrounding soil, suggesting selective ingestion of soil by S. gigas. This, together with the observation of increased concentration in POM with increasing aridity, suggests a major role of this species in the observed progressive gains of organic C stocks in no-till soils in the region.
Open Access
Pedogenic, mineralogical and land-use controls on organic carbon stabilization in two contrasting soils
(Agricultural Institute of Canada, 2010) Plante, A. F.; Virto Quecedo, Íñigo; Malhi, S. S.; Ciencias del Medio Natural; Natura Ingurunearen Zientziak
Organo-mineral complexation in soils is strongly controlled by pedogenesis, but the mechanisms controlling it and its interaction with cultivation are not yet well understood. We compared the mineralogy and quality of organic carbon (C) among organo-mineral fractions from two soils with contrasting pedogenic origin. Sequential density fractionation (SDF; using 1.6, 1.8, 2.1, 2.4 and 2.6 g mL(-1) sodium polytungstate solutions) followed by thermal analysis was applied to a Chernozem from Ellerslie, Alberta, and a Luvisol from Breton, Alberta, each under native and cultivated land uses. Similar clay mineralogy suggested that pedogenic controls on organic C stabilization were related to long-term vegetation cover. In addition to large differences in total organic C quantities, bulk soil and isolated fractions showed significant differences in organic C quality. Samples under native vegetation revealed greater organo-mineral complexation at Ellerslie compared with Breton, as expressed by less solubilisation, more organic C recovered in intermediate-density fractions, and exothermic differential scanning calorimetry peak signals associated with more stable forms of organic C. Long-term cultivation resulted in an overall shift to more stable organo-mineral complexes. The proportion of soil C in the 2.1-2.4 g mL(-1) fraction increased under cultivation from 21 to 32% in Breton samples, and from 6 to 16% in Ellerslie samples. The quality of inherited pedogenic soil organic C stored in a soil thus appears to determine its response to long-term cultivation.
Open Access
Organic carbon storage and dynamics as affected by the adoption of irrigation in a cultivated calcareous mediterranean soil
(Frontiers Media, 2022) Antón Sobejano, Rodrigo; Derrien, Delphine; Urmeneta Martín-Calero, Henar; Van der Heijden, Gregory; Enrique Martín, Alberto; Virto Quecedo, Íñigo; Zientziak; Estatistika, Informatika eta Matematika; Institute on Innovation and Sustainable Development in Food Chain - ISFOOD; Ciencias; Estadística, Informática y Matemáticas; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa
Irrigation is in the spotlight of land-use planning in semi-arid and sub-humid regions. It can be a promising practice to promote soil organic C storage (SOC), although it may also involve an increase in soil GHG emissions. Assessing the impact of its adoption on SOC storage is crucial to better understand its potential role in terms of agricultural sustainability and climate policies. In this study, we measured and modeled the changes in soil organic C storage and dynamics in the tilled soil layer (0-30 cm) of an experimental field on a calcareous soil with two different crops (maize, a C4 plant, and wheat, a C3 plant), cultivated with and without irrigation for 7 years. We hypothesized that changes in SOC storage occur when introducing irrigation and/or different crops in an agrosystem, and that they would be related to changes in the incorporation of crop residues, their partitioning between the labile and the stable fraction, and C losses bymineralization. Our results validated theses hypotheses only partially. Over the 7-year study period, irrigation significantly increased total (TOC) and sand-size (50-2,000 µm) particulate organic C (POC50-2,000) stocks in the tilled layer (0-30 cm): +7.1%TOC and +12.1%POC50-2,000 for maize, and +7.0 and +12.3% for wheat. A parallel two-pool SOC model based on TOC and POC50-2,000 fractions and the C3-C4 plant shift allowed understanding that the observed changes in SOC storage were most likely related to an increase in C inputs from crop residues, and to a more efficient incorporation of these residues with irrigation. The mean residence time of SOC in the two modeled pools did not allow to support our hypothesis of changes in SOC mineralization with irrigation. The limitations of SOC fractionation, which implied that some labile fractions might have been lost from POC50-2,000 and recovered in the fraction identified as slow-turning, together with the interaction of the carbonate-rich mineral phase of this soil can explain at least partially this observation. We conclude that irrigation can contribute to effectively increase SOC storage in themid-term, but its effectmight be dependent upon the type of crops and soil.
Open Access
Multi-modelling predictions show high uncertainty of required carbon input changes to reach a 4‰ target
(Wiley, 2022) Bruni, Elisa; Chenu, Claire; Abramoff, Rose Z.; Baldoni, Guido; Barkusky, Dietmar; Clivot, Hugues; Huang, Yuanyuan; Kätterer, Thomas; Pikula, Dorota; Spiegel, Heide; Virto Quecedo, Íñigo; Guenet, Bertrand; Ciencias; Zientziak
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.
Open Access
XXXIII Reunión Nacional de Suelos: libro de resúmenes
(2023) Arricibita Videgain, Javier; Valle de Lersundi, Jokin del; Enrique Martín, Alberto; Eslava Lecumberri, Javier; Lasarte Arangoa, Mikel; Ruiz Sagaseta de Ilurdoz, Alberto; Sanz Morales, Francisco Javier; Senar Mozo, Ainara; Virto Quecedo, Íñigo; Ciencias; Zientziak; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa
La XXXIII Reunión Nacional de Suelos (RENS) de la SECS, celebrada en Pamplona/Iruña del 12 al 15 de septiembre de 2023, pretende ser un foro para la comunidad científica vinculada a la Ciencia del Suelo que permita reflexionar acerca de los retos que enfrenta la disciplina en un ambiente de encuentro y de trabajo en campo. Al mismo tiempo, es una ocasión para el conocimiento de los suelos de Navarra y sus usos más relevantes, y que permite compartir trabajos de investigación recientes. En este libro de actas se recogen las comunicaciones presentadas a la XXXIII RENS, organizada por el área de Edafología y Química Agrícola de la Universidad Pública de Navarra (UPNA), el Departamento de Desarrollo Rural y Medio Ambiente del Gobierno de Navarra y la empresa pública Tracasa Instrumental.
Open Access
Soil quality evaluation following the implementation of permanent cover crops in semi-arid vineyards. Organic matter, physical and biological soil properties
(Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), 2012) Virto Quecedo, Íñigo; Imaz Gurruchaga, María José; Fernández Ugalde, Oihane; Urrutia Larrachea, Idoia; Enrique Martín, Alberto; Bescansa Miquel, Paloma; Ciencias del Medio Natural; Natura Ingurunearen Zientziak
El establecimiento de cubiertas vegetales permanentes (PGC) en viñedos de zonas semiáridas, con manejo tradicional de suelo desnudo mediante laboreo y aplicación de herbicidas, es controvertido, porque tiene ventajas agronómicas y ambientales, pero puede inducir cambios negativos en la calidad física del suelo. Los objetivos de este trabajo fueron: (i) avanzar en el conocimiento del efecto de la implantación de PGC en la calidad física y biológica del suelo, e (ii) identificar los indicadores de calidad del suelo más apropiados para suelos calizos de viñedo en una zona semiárida. Se determinaron propiedades físicas y biológicas clave en un Calcisol Cámbico con PGC de diferente edad (1 y 5 años), con un control manejado convencionalmente. El análisis de correlaciones mostró una relación directa entre la estabilidad estructural (WSA), la capacidad de retención de agua útil (AWC), la biomasa microbiana y las actividades enzimáticas del suelo bajo PGC. El contenido de C orgánico total (SOC) y lábil (POM-C) estuvo también correlacionado con los parámetros microbianos. Los indicadores de calidad del suelo más sensibles se identificaron mediante análisis factorial por componentes principales (PCA). La actividad de lombrices, AWC, WSA, SOC y POM-C mostraron el mayor peso en los dos factores obtenidos con PCA, por lo que estas propiedades pueden considerarse indicadores adecuados de la calidad del suelo en este agrosistema. Estos resultados indican que tanto los atributos físicos como biológicos del suelo son diferentes bajo PGC, y necesitan ser evaluados al estudiar las consecuencias de su introducción en suelos de viñedo.
Open Access
Changes in the soil inorganic carbon dynamics in the tilled layer of a semi-arid Mediterranean soil due to irrigation and a change in crop: uncertainties in the calculation of pedogenic carbonates
(Elsevier, 2024) De Soto García, Isabel Sonsoles; Barré, Pierre; Zamanian, Kazem; Urmeneta Martín-Calero, Henar; Antón Sobejano, Rodrigo; Enrique Martín, Alberto; Virto Quecedo, Íñigo; Ciencias; Zientziak; Institute on Innovation and Sustainable Development in Food Chain - ISFOOD; Estadística, Informática y Matemáticas; Estatistika, Informatika eta Matematika; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa
Soil inorganic carbon (SIC) accounts for more than one-third of the total soil carbon pool, but the effect of agricultural management on carbonates dynamics in Mediterranean semi-arid calcareous soils has largely been ignored and remains unclear. However, SIC plays a key role in physical, chemical and, biological properties of soils, which in turn can affect plant growth and productivity. Based on a 7-year field experiment in a paired irrigated and non-irrigated trial, with two different crops (maize and wheat), we investigated the effects of the land use change (from non-irrigated wheat to irrigated maize) on the SIC dynamics in the topsoil (0¿30 cm) of a carbonate-rich soil in Navarre, northern Spain. The results obtained using the accepted equation for determining carbonate type showed that during the 7-year study period, irrigation application and the crop change modified the carbonate typology (lithogenic and pedogenic) in a very short period, without affecting the total SIC content. The main drivers of pedogenic carbonate formation in this case appear to be the water volume and the type of organic matter entering the soil (from C3 plants or C4 plants). However, the equation seems to be strongly dependent on the type of soil organic carbon, which can introduce uncertainties when used to determine the proportion of pedogenic carbonates in soils experiencing a crop change from C3 to C4 plants.
Open Access
Soil carbon change (in mineral soils, organic soils and inorganic carbon)
(European Environment Agency, 2024) Arias-Navarro, Cristina; Rosa, Daniele de; Virto Quecedo, Íñigo; Poeplau, Christopher; Buttafuoco, Gabriele; Panagos, Panos; Jones, Arwyn; Ballabio, Cristiano; Lugato, Emanuele; Frank, Stefan; Chevallier, Tiphaine; Poch, Rosa María; Ciencias; Zientziak; Institute on Innovation and Sustainable Development in Food Chain - ISFOOD
Soil hosts the largest carbon pool in the terrestrial ecosystem, playing an essential role in the global carbon cycle and the regulation of climate change. Soil carbon is solid carbon stored in soils, existing in organic and inorganic forms. An important distinction between these two forms is that inorganic carbon has a much higher potential for permanence in soils than organic carbon. Soils are characterised as mineral or organic based on their organic matter content. Mineral soils form most of the world¿s cultivated land and may contain a trace of or up to 20 % organic matter. Organic soils are naturally rich in organic matter, principally due to vegetation and climate, and are distinguished from mineral soils by meeting specific criteria outlined in the IPCC guidelines for national GHG inventories (Drösler et al., 2014) and Food and Agriculture Organization (FAO) guidelines (FAO, 2006). These criteria include a thick organic horizon, a high organic carbon content, and the possibility of water saturation episodes.
Open Access
Effects of long-term sewage sludge addition to a calcareous soil on soil organic C fractions and soil functions
(Elsevier, 2024) Simoes da Mota, Ana Claudia; Barré, Pierre; Baudin, François; Poch, Rosa María; Bruni, Elisa; Antón Sobejano, Rodrigo; Enrique Martín, Alberto; Virto Quecedo, Íñigo; Ciencias; Zientziak; Institute on Innovation and Sustainable Development in Food Chain - ISFOOD
Soil organic matter (SOM) is a recognized carbon reservoir and paramount in soil functioning and agrosystems productivity. Different management strategies have been established to enhance SOM in arable soils, and one is the application of exogenous organic matter (EOM). Despite significant efforts in recent years, the consequences of EOM addition on increasing soil organic C (SOC) storage and stability in different pedoclimatic contexts remain incompletely understood. In this study, we evaluated the effect of long-term (28 y) sewage sludge (SS) addition to a calcareous soil supporting rainfed extensive crops in a Mediterranean sub-humid area in terms of SOC stabilization and distribution among functional fractions. To that end, we studied total SOM storage and soil fractions in a long-term experiment comparing 4 different doses of SS with mineral fertilization and no-fertilization controls. We compared the concentration, storage and distribution of C using two different fractionation methods (particulate vs. mineral-associated, defined by granulodensimetric fractionation, and active C vs. stable C defined by Rock-Eval® thermal analysis coupled to the machine learning PARTYsoc v2.0 model) on the tilled layer (0–30 cm). Three soil functioning indicators (crops yield, soil microbial biomass C and aggregate stability) were also quantified. We found that SS application, which slightly increased SOC concentration when SS was added, resulted in a net SOC stock gain only with the highest dose used (80 tons/ha), compared to mineral fertilization, suggesting that most of the C added was mineralized. An uneven response of soil fractions was however detected. The coarsest heavy physical fractions > 250 μm and 50–250 μm in size were the most enriched in their C concentration with SS addition, whereas SOC was mostly accumulated as mineral-associated C in the silt-size (2–50 μm) and the 50–250 μm fractions. Regarding thermal fractionation, SS treatments showed C gains between 57 % and 35 % in the active C pool, compared to mineral fertilization. This can be explained considering that the accumulated SOM in mineral-associated fractions corresponded to mean-residence times in the order of 20–40 years. The consequences on soil functioning indicators were not directly related to the amount of SOC stored in the soil, as the highest SOC gains corresponded to the highest dose, but not the highest yields, and some negative correlations were observed between SOC fractions and soil structural stability and microbial biomass. This can be related to some deleterious effects of excessive SS application reducing yields, the soil biological activity and soil structure, and represents an example of the need to decouple the assessment of soil health from that of SOC storage for certain soil management practices. The overall evaluation of the net consequences of long-term SS application indicated that low doses (10 tons/ha) seem a better choice, as they resulted in the highest efficiency in C incorporation, and in a slightly greater increase in SOC concentration than intermediate doses, and equal yields than mineral fertilization, but did not have the negative effects observed in soil functioning with higher doses.