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
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
Irrigation and SOC sequestration in the region of Navarre in Spain
(FAO, 2021) Virto Quecedo, Íñigo; Antón Sobejano, Rodrigo; Enrique Martín, Alberto; Orcaray Echeverría, Luis; Arias Fariñas, Nerea; Ciencias; Zientziak
The project REGADIOX, funded by the European Commission LIFE Program was based on the establishment of a regional-scale network of representative agricultural plots in three irrigation districts in Navarre (NE Spain). The project allowed for a rational evaluation of soil organic C (SOC) sequestration and greenhouse gases (GHG) emissions balances by using paired comparisons in terms of soil characteristics in irrigated vs rainfed plots. The results showed a clear influence of irrigation in soil condition, arising from greater SOC storage. The net effect was however modulated by soil characteristics and management practices, in so far as the different agricultural strategies did have different potential to sequester SOC and/or reduce GHG emissions. While permanent crops with green cover (which was possible thanks to irrigation) or semi-permanent crops as alfalfa were win-win strategies with positive C balances, intensive systems with two crops per year, although they also contributed to SOC gains, represented increased GHG emissions. The observed changes in SOC associated to irrigation with different managements also showed that irrigation adoption can alter the soils’ capacity to provide key ecosystem services beyond biomass production, as changes in soils properties related to SOC, such as water-holding capacity or soil erodibility were also observed. These changes were, however, not straightforward and varied depending on soil type, climate and time under irrigation.
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 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
Oinez Basoa: using school-managed afforested land for soil education in Navarre, Spain
(Universia España, 2019) Virto Quecedo, Íñigo; Imbert Rodríguez, Bosco; Peralta de Andrés, Francisco Javier; De Soto García, Isabel Sonsoles; González Tejedor, Iñaki; Antón Sobejano, Rodrigo; López Goñi, Irene; Martínez, Maite; Arias, Isabel; Enrique Martín, Alberto; Ciencias; Zientziak; Gobierno de Navarra / Nafarroako Gobernua
El estudio del suelo en la educación secundaria es un tema de debate ya que, a pesar de la creciente preocupación por el suelo en las ciencias ambientales, sigue siendo poco considerado en los planes de estudio y programas oficiales de educación preuniversitaria. En este trabajo presentamos los resultados de un estudio de caso realizado con una clase de 4º grado de educación secundaria obligatoria, donde se utilizó una secuencia didáctica que incluye datos reales obtenidos en una cronosecuencia de reforestación. La repoblación forestal formó parte de las actividades realizadas por la red de escuelas a las que pertenecía la escuela, con el objetivo de mitigar las emisiones de gases de efecto invernadero resultantes de su actividad anual de recaudación de fondos. En un primer paso, se determinaron una serie de indicadores edáficos y de la vegetación en el suelo reforestado, utilizando un enfoque de espacio por tiempo con un suelo cultivado cercano (correspondiente a la situación original del suelo reforestado) y un bosque maduro (similar a la situación objetivo de la reforestación). Se observó que los índices de biodiversidad de plantas, carbono de la biomasa microbiana y C orgánico total, y los de descomposición de la materia orgánica en el suelo reforestado se encontraron en una situación intermedia entre el suelo cultivado y el bosque maduro. En particular, se verificó un secuestro efectivo de C atmosférico a partir de una diferencia de 12,41 ± 1,06 Mg de C orgánico por hectárea en el suelo reforestado en comparación con el control cultivado. Los datos emitidos a partir de este análisis se utilizaron para preparar una actividad de aprendizaje cooperativo de tipo puzzle, que se integró en la secuencia didáctica diseñada para introducir los conceptos de sucesiones ecológicas y el ciclo del carbono. Esta propuesta se centró especialmente en el papel del suelo como omponente del ecosistema y dentro del ciclo del C. El éxito de la implementación de esta secuencia se probó utilizando test de conocimientos previos y finales. Los resultados de estas pruebas mostraron una mejora general (42,8 puntos en la prueba final frente a 23,3 en la prueba inicial) en relación con los conceptos evaluados. Sin embargo, se observaron diferencias en relación a la progresión realizada por los estudiantes, que fue mejor en las preguntas relacionadas con los ecosistemas que en las directamente relacionadas con el suelo como consecuencia del peor conocimiento previo sobre el suelo. A partir de estos resultados, llegamos a la conclusión de que el desarrollo de herramientas educativas que permitan a los estudiantes de secundaria abordar casos reales en las que el suelo se considera un componente clave del ecosistema, puede ser eficaz para avanzar hacia un aprendizaje significativo sobre los suelos y las propiedades del suelo, que parecen no suficientemente entendidos por los alumnos de educación secundaria.
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
Soil degradation and soil quality in Western Europe: current situation and future perspectives
(MDPI, 2015) Virto Quecedo, Íñigo; Imaz Gurruchaga, María José; Fernández Ugalde, Oihane; Gartzia Bengoetxea, Nahia; Enrique Martín, Alberto; Bescansa Miquel, Paloma; Ciencias del Medio Natural; Natura Ingurunearen Zientziak
The extent and causes of chemical, physical and biological degradation of soil, and of soil loss, vary greatly in different countries in Western Europe. The objective of this review paper is to examine these issues and also strategies for soil protection and future perspectives for soil quality evaluation, in light of present legislation aimed at soil protection. Agriculture and forestry are the main causes of many of the above problems, especially physical degradation, erosion and organic matter loss. Land take and soil sealing have increased in recent decades, further enhancing the problems. In agricultural land, conservation farming, organic farming and other soil-friendly practices have been seen to have site-specific effects, depending on the soil characteristics and the particular types of land use and land users. No single soil management strategy is suitable for all regions, soil types and soil uses. Except for soil contamination, specific legislation for soil protection is lacking in Western Europe. The Thematic Strategy for Soil Protection in the European Union has produced valuable information and has encouraged the development of networks and databases. However, soil degradation is addressed only indirectly in environmental policies and through the Common Agricultural Policy of the European Union, which promotes farming practices that support soil conservation. Despite these efforts, there remains a need for soil monitoring networks and decision-support systems aimed at optimization of soil quality in the region. The pressure on European soils will continue in the future, and a clearly defined regulatory framework is needed.
Open Access
Tillage effects on soil quality after three years of irrigation in Northern Spain
(MDPI, 2017) Apesteguía Barberena, Marcos; Virto Quecedo, Íñigo; Orcaray Echeverría, Luis; Bescansa Miquel, Paloma; Enrique Martín, Alberto; Imaz Gurruchaga, María José; Karlen, Douglas; Ciencias del Medio Natural; Natura Ingurunearen Zientziak
Irrigation is being initiated on large areas of traditionally rainfed land to meet increasing global demand for food, feed, fiber and fuel. However, the consequences of this transition on soil quality (SQ) have scarcely been studied. Therefore, after previously identifying the most tillage-sensitive SQ indicators under long-term rainfed conditions, conversion of a research site on a Haplic Calcisol in Navarre, in northeast Spain provided an ideal location to reevaluate those SQ indicators after three years of irrigated management. The Soil Management Assessment Framework (SMAF) was used to test our hypothesis that adopting irrigation could change the sensitivity and importance of non-irrigated SQ indicators. Several soil physical, chemical, and biological indicators along with crop yields were used to evaluate SQ three years after initiating irrigation on a long-term conventional tillage (CT), minimum tillage (MT) and no-tillage (NT) study where either barley (Hordeum vulgare L.) or wheat (Triticum aestivum L.) was being grown. The results confirmed our hypothesis that irrigation would change the relative importance of various SQ indicators and suggested that some SMAF algorithms, such as those used to assess bulk density, needed to be recalibrated for these Mediterranean soils.
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.