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.
Open Access
Soil organic carbon monitoring to assess agricultural climate change adaptation practices in Navarre, Spain
(Springer, 2021) Antón Sobejano, Rodrigo; Arricibita Bidegáin, Francisco Javier; Ruiz Sagaseta de Ilurdoz, Alberto; Enrique Martín, Alberto; De Soto García, Isabel Sonsoles; Orcaray Echeverría, Luis; Zaragüeta, Armelle; Virto Quecedo, Íñigo; Zientziak; Institute on Innovation and Sustainable Development in Food Chain - ISFOOD; Ciencias; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa
Climate change adaptation strategies are needed for agriculture, one of the most vulnerable human activities. In Navarre, North of Spain, ongoing adaptive management practices were identified and promoted in the framework of a regional adaptation strategy. Most include practices aiming to increase topsoil organic carbon (SOC) in agricultural land. In this work, the effectiveness of these practices (conservation agriculture, crop rotations, additions of organic matter, irrigation, and controlled grazing management) was assessed by means of monitoring SOC in a network of 159 agricultural fields across the region. These fields were selected across bioclimatic zones, where soil vulnerabilities and land-uses were previously assessed, to represent the most widespread conditions in the region. A sampling protocol designed to compare SOC stocks in plots with equal soil conditions within each zone, and with or without adaptive practices, allowed the determination of their effect size (measured as response ratios, RR). Exogenous organic matter addition was the most effective practice for SOC storage (RR 95% confidence interval (CI) [1.25–1.37]) across the region. Controlled grazing also resulted in net SOC gains (RR CI [1.13–1.42]) in temperate and semiarid grasslands. Conservation agriculture seemed to be more effective in the driest zone (RR CI [1.30–1.53]) than in the more humid ones (RR CI [0.98–1.21]). Irrigation also displayed a net positive effect (RR CI [1.17–1.34]), modulated by irrigated crop management, whereas crop rotations had an overall negative impact vs. monoculture (RR CI [0.84–0.96]), likely by their interaction with irrigation. These results confirm the variability in SOC responses to changes in management, and SOC as an indicator for assessing regional adaptation practices, although other biophysical, agronomic, and socio-economic factors also need to be accounted for.
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
XXXIII Reunión Nacional de Suelos: libro de resúmenes
(2023) Arricibita Bidegáin, Francisco 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 assessment after 25 years of sewage sludge vs. mineral fertilization in a calcareous soil
(MDPI, 2021) Simoes da Mota, Ana Claudia; Poch, Rosa María; Enrique Martín, Alberto; Orcaray Echeverría, Luis; Virto Quecedo, Íñigo; Institute on Innovation and Sustainable Development in Food Chain - ISFOOD
The aim of this work was to identify the most sensitive soil quality indicators and assess soil quality after long-term application of sewage sludge (SS) and conventional mineral fertilization for rainfed cereal production in a sub-humid Mediterranean calcareous soil. The treatments included six combinations of SS at different doses (40 t ha−1 and 80 ha−1) and frequencies (every 1, 2 and 4 years), plus a control with mineral fertilization, and a baseline control without fertilization. Twenty-five years after the onset of the experiment, 37 pre-selected physical, chemical and biological soil parameters were measured, and a minimum data set was determined. Among these indicators, those significantly affected by treatment and depth were selected as sensitive. A principal component analysis (PCA) was then performed for each studied depth. At 0–15 cm, PCA identified three factors (F1, F2 and F3), and at 15–30 cm, two factors (F4 and F5) that explained 71.5% and 67.4% of the variation, respectively, in the soil parameters. The most sensitive indicators (those with the highest correlation within each factor) were related to nutrients (P and N), organic matter, and trace metals (F1 and F4), microporosity (F2), earthworm activity (F3), and exchangeable cations (F5). Only F3 correlated significantly (and negatively) with yield. From these results, we concluded that soil quality can be affected in opposite directions by SS application, and that a holistic approach is needed to better assess soil functioning under SS fertilization in this type of agrosystem.
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
Effect of irrigation on carbonate dynamics in a calcareous soil using isotopic determinations
(Universia, 2019) De Soto García, Isabel Sonsoles; Virto Quecedo, Íñigo; Barré, Pierre; Enrique Martín, Alberto; Zientziak; Institute on Innovation and Sustainable Development in Food Chain - ISFOOD; Ciencias
Este artículo evalúa el efecto del regadío en la dinámica de los carbonatos en suelos agrícolas. Se ha estudiado la proporción y distribución de carbonatos pedogénicos en las fracciones granulométricas de un suelo en regadío y en secano, usando la firma isotópica de C de los carbonatos. El regadío puede alterar la distribución de los carbonatos del suelo y producir una acumulación preferencial de carbonatos pedogénicos (87% al 92% con riego frente a 61% al 74% sin riego) en las fracciones más finas.
Open Access
Soil water retention and soil compaction assessment in a regional-scale strategy to improve climate change adaptation of agriculture in Navarre, Spain
(MDPI, 2021) Antón Sobejano, Rodrigo; Ruiz Sagaseta de Ilurdoz, Alberto; Orcaray Echeverría, Luis; Arricibita Bidegáin, Francisco Javier; Enrique Martín, Alberto; De Soto García, Isabel Sonsoles; Virto Quecedo, Íñigo; Zientziak; Institute on Innovation and Sustainable Development in Food Chain - ISFOOD; Ciencias; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa
The aim of this study was to evaluate the effectiveness of the different agricultural management adaptive strategies considered in the framework of a regional climate change adaptation roadmap in Navarre (Spain), from the point of view of soil physical indicators associated to soil compaction and water retention. These indicators were chosen as representative of the potential of these strategies to improve the soil physical condition. That for, the effectiveness of conservation agriculture (CA), crop rotations (ROT), additions of organic matter (ExO), irrigation (IRR) and innovative grassland management (GSS) was assessed by monitoring soil bulk density (BD) and soil available water holding capacity (AWHC) in a network of 159 agricultural fields across homogeneous agro-climatic zones in the region. A sampling protocol designed to compare groups of plots with or without adaptive practices, and with equal soil characteristics within each zone, allowed to determine the effect size of each strategy (measured as response ratios, RR, calculated as the relative value of BD and AWHC in fields with adaptive management vs. without). Both parameters responded to soil and crop management, although the observed effect was highly variable. Only the ExO strategy showed an overall positive effect on BD. ROT, IRR and GSS displayed no effect and, in the case of CA, the effect was negative. In terms of AWHC, although the results within the zones were heterogeneous, the overall effect associated to the strategies ROT, ExO, IRR and GSS was neutral, and only CA resulted in an overall negative effect. The observed variability in terms of the effectiveness of the five strategies tested in this region highlights the need to understand the complexity of interrelationships between management and dynamic soil properties at the regional scale.
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
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.