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Land abandonment in the Mediterranean mountains since the 20th century has led to a reduction of ecosystem services, due to revegetation and homogenization of the landscape. To counteract these effects, the regional administration of La Rioja in Spain initiated a Plan for Shrub Clearing (PSC) combined with extensive livestock grazing in 1986, which is still in action today. This study analyses the effects of pairing clearing with grazing in an experimental area of the Leza valley (Iberian System) on: (i) the landscape structure and structural diversity; (ii) the production of pasture; (iii) fire control; (iv) soil organic carbon sequestration (also considering soil environmental types); (v) surface water resources. The results show that: (i) a more fragmented landscape with greater diversity is created; (ii) grazing land is almost doubled in alkaline soils and four-fold in siliceous soils; (iii) fires are considerably reduced, with the mean surface fire spread falling from 34.1 ha/year from 1968 to 1985, to 1.2 ha/year between 1986 and 2022; (iv) regenerated post-clearance grazing soils sequester more organic carbon than that of shrublands, especially older clearings on alkaline soils (55.3 % more); (v) clearing increases hydrological connectivity and water resources. The conclusion is that managing the Mediterranean mid-mountains could be a very effective strategy to improve the supply of certain ecosystem services and improve the current socio-economic perspective of these marginal areas in a context of Global Change. The PSC also contributes to local development by increasing livestock numbers.

Forest expansion in Mediterranean mountain areas is a widespread phenomenon resulting from the abandonment of agricultural and pastoral activities during the last century. Therefore, knowledge of the long-term storage capacity of soil organic carbon (SOC) in Mediterranean forests is of great interest in the context of global change. However, the effects of these land uses and covers (natural secondary forest, afforestation with conifers and silvo-pastoral ecosystems (dehesas)) on SOC dynamics are still uncertain. The main objectives of this study were to evaluate physico-chemical soil properties, SOC and nitrogen stocks, and SOC fractions in Mediterranean forests and to assess the effects of tree species, the soil environment (acidic and alkaline), and land management. We selected five land uses and land covers: managed and non-managed afforestation and dehesa (except for alkaline dehesa) and a stage of succession when tree species begin to become established after abandonment. This study concludes that although total SOC stocks are higher in afforested systems with conifers, SOC is stored in less stable carbon pools than in broadleaf forests. In addition, this study confirms that there are marked differences in the results between acidic and alkaline environments. Finally, the management system is also a significant factor, particularly for afforested sites.

[Context] The Mediterranean mountains have witnessed the revegetation of former pasture and cultivated fields since the mid-20th century. The process started when the mountains joined a dynamic and competitive market, which led to depopulation, abandoning cultivated fields, and a reduction in extensive livestock farming., [Objectives] We investigate changes in land use and land cover (LULC) and landscape structure in a valley of the Central Pyrenees in 1956, 1981 and 2017, and we discuss the implications for land management within a multidisciplinary context., [Methods] Aerial photographs are used to map the LULC in 1956, 1981 and 2017, followed by landscape ecology metrics and indices to analyse the structure of the landscape., [Results] The results show: (i) a reduction in cultivated area (-42%) and pastures (-63%) in the montane belt between 1956 and 2017, while forests doubled in area; (ii) changes in LULC are more significant in the montane belt than in subalpine and alpine areas; (iii) based on the Kappa index, it was found that the 29% of the area had undergone changes in LULC between 1956 and 2017, with the changes being greater in the first period (1956–1981) than in the second (1981–2017); (iv) the structure and heterogeneity of the landscape shows an increase between 1956 and 1981, and a change in trend from 1981 to 2017, so that the landscape is more homogeneous in 2017 than in 1956., [Conclusion] The discussion suggests the need to maintain and recover mosaic landscapes, since their structure is akin to traditional cultural ones, to increase biodiversity and sustainability, and provide ecosystem services to the population.

[EN] Wine production consistently exceeds wine consumption on a global scale, which explains why the wine market is highly demanding, competitive and increasingly international. This paper quantifies the changes (between 1995 and 2019) in wine consumption, production and the international wine market. Traditionally, the international wine sector was managed from Europe, mainly by a group of countries (Spain, France, Italy and Portugal) that concentrated most of the vineyards, production and international trade. Since the end of the 20th century, several countries (USA, Canada, Chile, Argentina, South Africa, Australia and New Zealand) have made strong inroads into the sector, increasing their vineyard surface area and having a significant and growing presence in international markets. On the other hand, other countries (China, Russia, Brazil, India, the Netherlands, Japan, etc.) are emerging in wine consumption. All this has changed the geographical distribution of vineyards and wine production, moving progressively from the "Old World" to the "New World". In 1961, Europe accounted for almost 69% of the world's vineyards, whereas in 2019 it will account for only 50%. On the other hand, wine imports and exports doubled between 1995 and 2019, while the number of wine-producing and wine-consuming countries is increasing. The globalisation of the wine market has driven changes in wine production and winemaking systems, as well as the regulation of international trade to take into account competition from non-EU wines, issues that simply discussed in this paper., [ES] La producción de vino supera su consumo de manera sistemática a escala mundial, lo que explica que el mercado del vino sea muy exigente, competitivo y cada vez más internacional. En este trabajo se cuantifican los cambios (entre 1995 y 2019) en el consumo, producción y mercado internacional del vino. Tradicionalmente, el sector vitivinícola internacional se gestionaba desde Europa, principalmente por un grupo de países (España, Francia, Italia y Portugal) que concentraban la mayor parte del viñedo, la producción y el comercio internacional. Desde finales del siglo XX, acceden con fuerza al sector varios países (EE.UU., Canadá, Chile, Argentina, Sudáfrica, Australia y Nueva Zelanda) que incrementan su superficie de viñedo y tienen una presencia relevante y creciente en los mercados internacionales. Por otro lado, otros países (China, Rusia, Brasil, India, Países Bajos, Japón...) emergen en el consumo de vino. Todo ello ha cambiado la distribución geográfica del viñedo y de la producción de vino, trasladándose progresivamente del “Viejo Mundo” al “Nuevo Mundo”. En 1961, Europa concentraba casi el 69% del viñedo mundial, mientras que en 2019 tan sólo la mitad. Por otro lado, entre 1995 y 2019 se duplicaron las importaciones y exportaciones de vino, a la vez que aumenta el número de países productores y consumidores de vino. La globalización del mercado del vino ha impulsado cambios en los sistemas de producción y elaboración de vino, así como la regulación del comercio internacional para tener en cuenta la competencia de los vinos de fuera de la UE, cuestiones que en este trabajo simplemente se apuntan.

Climate variables including temperature, rainfall intensity, rainfall acidity, and lithological properties are among the most important factors affecting rock weathering. However, the relative contribution of these four factors on rock weathering, especially on chemical weathering, is still unclear. In this study, we carried out a series of weathering-leaching rainfall simulations on four types of badland sediments under controlled conditions of two levels of temperature, rainfall intensity, and rainfall acidity based on the real field data from representative weather scenarios. The main objectives are 1) to explore the progressive change of sample surface and leachate characteristics and 2) to reveal the independent effects of temperature, rainfall intensity, rainfall acidity, and lithology and their relative contribution as well, on both mechanical and chemical weathering. Qualitative analysis on crack development and fragmentation of sample surface and quantitative analysis on the leachate volume, pH, electrical conductivity, and total cation and anion releases of sample leachate together demonstrated that for the investigated sediments, under the conditions of temperature, intensity, and acidity of rain that can be achieved in nature, high drying temperature obviously increases mechanical disintegration by promoting the rate and magnitude of moisture variations (wetting–drying alterations), while high rainfall intensity and acid rain have no obvious effect. Impact and importance of the drying process caused by high temperature between wetting events need more attention, rather than high rainfall intensity. Low temperature, high rainfall intensity, and acid rain contributing more hydrogen ions required for cation exchanges, rock type with more soluble minerals, all promote chemical weathering, and the influence of climatic and lithological factors on chemical weathering decreases in the following order: mineral composition> rainfall intensity > temperature > rain

Abandoned cropland areas have the potential to contribute to climate change mitigation through natural revegetation and afforestation programs. These programs increase above and belowground carbon sequestration by expanding forest cover. However, this potential to mitigate climate change often involves tradeoffs between carbon sequestration and water availability. Particularly in a water limited environments such as the Mediterranean region, any loss of recharge to groundwater or streamflow can have critical societal consequences. In this study, we used an ecohydrologic model, Regional Hydro-Ecological Simulation System (RHESSys), to quantify these tradeoffs for land management plans in abandoned cropland areas in Mediterranean mountains. Changes to Net Ecosystem Production (NEP), water yield and Water-Use Efficiency (WUE) under different land management and climate scenarios were estimated for Arnás, a catchment with similar geology, vegetation and climate to many of the locations targeted for land abandonment restoration in the Spanish Pyrenees. Results showed significant changes to both carbon and water fluxes related to land management, while changes related to a warming scenario were not significant. Afforestation scenarios showed the highest average annual carbon sequestration rates (112 g C·m−2·yr−1) but were also associated with the lowest water yield (runoff coefficient of 26%) and water use efficiency (1.4 g C·mm−1) compared to natural revegetation (−27 g C·m−2·yr−1, 50%, 1.7 g C·mm−1 respectively). Under both restoration scenarios, results showed that the catchment ecosystem is a carbon sink during mid-February to July, coinciding with peak monthly transpiration and WUE, while during the rest of the year the catchment ecosystem is a carbon source. These results contribute to understanding carbon and water tradeoffs in Mediterranean mountains and can help adapt restoration plans to address both carbon sequestration and water management objectives.

In slopes of Mediterranean mid-mountain areas, land use and land cover changes linked to the abandonment of cropland activity affect soil quality and degradation and soil redistribution; however, limited attention has been paid to this issue at catchment scale. This paper evaluates the effects of cropland abandonment and post-land abandonment management (through natural revegetation and afforestation) on soil redistribution rates using fallout 137Cs measurements in the Araguás catchment (0.45 km2, Central Spanish Pyrenees). A total of 52 soil core samples, distributed in a regular grid, from the first 30–40 cm and 9 sectioned reference samples were collected across the catchment and soil properties were analysed. Fallout 137Cs was measured in a 5 cm sectioned references samples and in bulk grid samples. 137Cs inventories were used to estimate soil erosion and deposition rates across the catchment. Results show that the highest erosion rates were recorded under sparsely vegetated sites in the badland area, while the lowest rates were found in the afforested area, but no significant differences were observed between the different uses and covers in soil redistribution rates likely due to a long history of human intervention through cultivation in steep slopes and afforestation practices. However, the recovery of the soil organic matter in afforested areas suggest that afforestation can reduce soil degradation at long-term scale. The information gained achieve a better understanding of soil redistribution dynamics and provide knowledge for effective land management after cropland abandonment of agroecosystems in Mediterranean mountain areas.

Mediterranean mountains are sensitive agroecosystems that have suffered intense land use and land cover changes (LULCC) during the last century. From the middle of the twentieth century, most of the cultivated lands in Mediterranean mountains were abandoned, allowing the recovery of vegetation (through natural revegetation and afforestation programmes). To examine the effects of farmland abandonment, secondary succession (natural revegetation) and afforestation, an intensive soil sampling was carried out in the Araguás catchment (Central Spanish Pyrenees) including sparsely vegetated areas (badlands), grasslands, shrublands and afforested sites. LULCC were mapped, and soil physico-chemical properties were analysed in reference sites (unaltered areas during the last centuries) and in the different land uses. Likewise, the soil organic carbon (SOC) content in the bulk soils and in the fractions separated by density fractionation have been studied. This study evidenced that farmland abandonment led to a mosaic landscape with different land use and land covers. Results show that LULCC significantly affect soil physico-chemical properties (soil texture, stoniness, pH, SOC, total carbon, CorgN ratio, bulk density and field capacity). Significant differences were observed between secondary and afforested sites following farmland abandonment. Afforestation triggered higher SOC than shrubland sites (natural revegetation) (1.4 and 1.1% respectively), suggesting a slower process of organic matter accumulation after farmland abandonment in the natural revegetation compared to afforestation. The significant role of grassland sites for enhancing the accumulation of SOC has been also confirmed. The results showed also significant differences in the relative contribution of each organic fraction to the bulk SOC: the amount of labile fraction (free and occluded labile fractions) is significantly higher in afforested and shrubland sites (58.1 and 51.2% respectively) than in grassland

Farmland abandonment has become one of the most important land use and land cover (LULC) changes threatening mountain areas in the Mediterranean. The concomitant natural revegetation process brings with it a series of ecosystem services and disservices for these marginal areas. Secondary succession can improve soil environment properties; however, its effects can be influenced by the specific characteristics of the site (topography, climate, vegetation, etc.). Thus, the main objective of this research was to study how soil quality and carbon sequestration are affected by post-abandonment secondary succession depending on the environment (delimited from the bedrock and the typical vegetation communities of the area. Soil sampling was carried out in a representative area of the Mediterranean mid-mountains (Leza Valley, Spain) for two soil environments (acid and alkaline), at different depths (0–40 cm) and in 5 stages of the abandonment process: cropland (CRL); shrubland (SH); bushland (BS); young forest (YF); and old forest (OF). Soil physico-chemical parameters were analysed and data analysis carried out with the following results: (i) significant differences were detected between environments for most LULCs; (ii) LULC, depth and soil environment significantly affected most of the soil variables studied; (iii) alkaline soil environments showed a progressive increase of soil organic carbon (SOC) and total nitrogen (N) stocks as the revegetation process and age of abandonment advanced (from 101.16 Mg ha−1 SOC (CRL) to 181.68 Mg ha−1 SOC (OF); (iv) in acid soil environments, the highest stocks were observed in the YF (161.56 Mg ha−1 SOC) with an irregular evolution pattern. Our study showed that secondary succession can improve soil quality and SOC sequestration. However, factors such as soil environment may be of great importance in selecting the best post-abandonment management strategy in a bid to gain recovery of ecosystem services and mitigate the effects of Global

As a network of researchers we release an open-access database (EUSEDcollab) of water discharge and suspended sediment yield time series records collected in small to medium sized catchments in Europe. EUSEDcollab is compiled to overcome the scarcity of open-access data at relevant spatial scales for studies on runoff, soil loss by water erosion and sediment delivery. Multi-source measurement data from numerous researchers and institutions were harmonised into a common time series and metadata structure. Data reuse is facilitated through accompanying metadata descriptors providing background technical information for each monitoring station setup. Across ten European countries, EUSEDcollab covers over 1600 catchment years of data from 245 catchments at event (11 catchments), daily (22 catchments) and monthly (212 catchments) temporal resolution, and is unique in its focus on small to medium catchment drainage areas (median = 43 km2, min = 0.04 km2, max = 817 km2) with applicability for soil erosion research. We release this database with the aim of uniting people, knowledge and data through the European Union Soil Observatory (EUSO).

Management policies after abandonment in Mediterranean mid-mountains have encouraged the establishment of afforestations being considered as an NBS. Related to the implication on soil afforestation can (i) accelerate the recovery of some soil properties but it is necessary for long time periods, (ii) change above- and belowground litter quality and quantity producing a constant SOC accumulation, (iii) improve aggregate stability, and (iv) increase the presence of macro-aggregates and the water holding capacity of the soil. Likewise, afforestation threatens water resources: (i) reduces the number of floods; (ii) decreases annual water yield; (iii) delays peak flows but increases the duration of floods; (iv) increases interception of rainfall, and (iv) typically reduces the erosion risk and the volume of sediment, but not during the first years due to high geomorphic activity. However, there is still considerable scientific uncertainty and research on the impacts of afforestation in soil and water conservation is still needed.

Soil piping is a widespread, although often overlooked land degradation process. So far, subsurface soil erosion studies have been focused on the importance of soil piping in hydrological and geomorphological processes, and factors controlling piping processes. Nowadays, the environmental changes being caused by the Anthropocene have clearly demonstrated that society depends on soil more than ever before, so the traditional studies of soil erosion processes need to be redefined. In that sense, geomorphologists face to overcome new piping-related problems. In this article we identify new possible areas of research: (i) soil pipes and pipe collapses (PCs) as natural hazards, (ii) role of soil piping in carbon cycle, (iii) soil pipes and PCs and their relationships with biodiversity, and (iv) piping-affected areas as geodiversity sites. Only better recognition of natural hazards driven by soil piping, such as land subsidence and degradation, landslides, flooding and off-site sediment effects may result in better prevention and control measures in piping-affected areas. Moreover, in the context of Global Change the role of soil piping in carbon cycle should be raised. Land-use and land-cover changes, as well as climate change may affect piping dynamics in different morphoclimatic regions and soil loss due to piping may lead to carbon loss. Soil pipes and PCs are closely interlinked with biodiversity, both positively and negatively. Piping erosion may directly and indirectly destroy vegetation and animals, although in some cases piping erosion may create new habitats and provide favourable conditions for some species. However, soil piping is not only an environmental and societal problem, but it may also contribute to the world geodiversity, which is clearly observed in badland sites. Piping erosion may have a significant impact on environment and society, thus further research with new questions is essential to provide knowledge for sustainable development.

[EN] The XVI National Meeting of Geomorphology will be held in Zaragoza next September. The meeting will be organized by members of the research team recognized by the Government of Aragón Geoenvironmental Processes and Global Change (E02_23R) belonging to both the University of Zaragoza and the Consejo Superior de Investigaciones Científicas. Around 100 people were expected to participate and a total of 91 abstracts were received., [ES] El próximo mes de septiembre se celebrará en Zaragoza la XVI Reunión Nacional de Geomorfología. La organización de la reunión correrá a cuenta de los miembros del equipo de investigación reconocido por el Gobierno de Aragón Procesos Geoambientales y Cambio Global (E02_23R) pertenecientes tanto a la Universidad de Zaragoza como al Consejo Superior de Investigaciones Científicas. Se ha previsto una participación en torno a 100 personas y se han recibido un total de 91 resúmenes.