• Energy Research

This article enhances some ideas and opinions related with the challenges that women across the world face nowadays to pursue a professional career. The route they take has frequent obstacles of a distinct nature, which are not always comparable with those faced by men. The starting point of this work is the conclusions of the workshop “Women empowerment and gender equality, responsible research and innovation”—Research Project “SOILdarity”. This workshop revealed a diversified view about the subject, evidencing its connection with the social sustainability, with a special focus on academia and research management. This document introduces the topic in the context of the workshop, revises key aspects of women’s empowerment in a society still dominated by men’s opinions and organization (gender balance, obstacles and strategies), highlights the situation of women in academia and in research management, and gives the authors’ opinions about some questions related to gender and equality. We conclude that all societal actors must acknowledge women as key actors in contributing to social sustainability, working together towards creating an environment where they can have leadership roles.

AbstractClimate change and atmospheric nitrogen (N) deposition are two of the most important global change drivers. However, the interactions of these drivers have not been well studied. We aimed to assess how the combined effect of soil N additions and more frequent soil drying–rewetting events affects carbon (C) and N cycling, soil:atmosphere greenhouse gas (GHG) exchange, and functional microbial diversity. We manipulated the frequency of soil drying–rewetting events in soils from ambient and N‐treated plots in a temperate forest and calculated the Orwin & Wardle Resistance index to compare the response of the different treatments. Increases in drying–rewetting cycles led to reductions in soil levels, potential net nitrification rate, and soil : atmosphere GHG exchange, and increases in and total soil inorganic N levels. N‐treated soils were more resistant to changes in the frequency of drying–rewetting cycles, and this resistance was stronger for C‐ than for N‐related variables. Both the long‐term N addition and the drying–rewetting treatment altered the functionality of the soil microbial population and its functional diversity. Our results suggest that increasing the frequency of drying–rewetting cycles can affect the ability of soil to cycle C and N and soil : atmosphere GHG exchange and that the response to this increase is modulated by soil N enrichment.

Increased atmospheric nitrogen (N) deposition is known to alter ecosystem carbon source-sink dynamics through changes in soil CO2 fluxes. However, a limited number of experiments have been conducted to assess the effects of realistic N deposition in the Mediterranean Basin, and none of them have explored the effects of N addition on soil respiration (R s ). To fill this gap, we assessed the effects of N supply on R s dynamics in the following two Mediterranean sites: Capo Caccia (Italy), where 30 kg ha-1 year-1 was supplied for 3 years, and El Regajal (Spain), where plots were treated with 10, 20, or 50 kg N ha-1 year-1 for 8 years. Results show a complex, non-linear response of soil respiration (R s ) to N additions with R s overall increasing at Capo Caccia and decreasing at El Regajal. This suggests that the response of R s to N addition depends on dose and duration of N supply, and the existence of a threshold above which the N introduced in the ecosystem can affect the ecosystem's functioning. Soil cover and seasonality of precipitations also play a key role in determining the effects of N on R s as shown by the different responses observed across seasons and in bare soil vs. the soil under canopy of the dominant species. These results show how increasing rates of N addition may influence soil C dynamics in semiarid ecosystems in the Mediterranean Basin and represent a valuable contribution for the understanding and the protection of Mediterranean ecosystems.

Rationale: Increased aridity has led to drought-induced mortality or loss of health for many tree species. Of particular interest is to explore the response of the Mediterranean tree species cork oak (Quercus suber) to this declining phenomenon due to its severity and its large implications for the local economy and the provision of highly relevant ecosystem services. Approach: To assess geographical variations in the response to water stress, we analyzed under controlled conditions the effects of four watering levels and the resistance to a terminal drought on seedlings collected from nine populations covering the complete latitudinal distribution of the species. We explored the response of a number of physiological traits and markers of oxidative stress potentially related with drought-resistance. Findings: We found a highly plastic phenotypic response of most variables to water availability and a large influence of seedlings provenance in the drought-resistance strategies. Although the oxidative stress enzymes ruled out differential water stress throughout the distribution range, we found that seedlings from the southern limit are less vulnerable to drought than other populations. Southern seedlings adapted to xeric conditions displayed a larger sensitivity of stomata to changes in soil humidity and a higher water use efficiency. These physiological local adaptations coupled with larger acorn size in the southern populations, resulted in larger aboveground biomass and higher drought resistance at the southern distribution edge. Conclusions: Our data suggest that this evergreen tree species relies on its physiological plasticity to develop adaptative features that allows it to overcome water shortage and that southern populations hold genetic diversity that could improve the specie´s adaptation in the forecasted drought context with relevant implications for conservation programs. Ministerio de Ciencia, Innovación y Universidades PID2019-108288R y CNS2022-135560 Consejo Andaluz de Economía, Conocimiento y Universidades FEDER US-1380871

SummaryParasitic plants are important drivers of community and ecosystem properties. In this study, we identify different mechanisms by which mistletoe (Viscum albumsubsp.austriacum) can affect soil chemical and biological properties at different temporal stages of parasitism.We quantified the effect of parasitism on host growth and the number of frugivorous mutualists visiting the host canopy. Then we collected, identified, and weighed the organic matter input underneath tree canopies and analyzed its nutrient content. Simultaneously, we analyzed soil samples under tree canopies and examined the chemical properties, microbial abundance, and functional evenness of heterotrophic microbial communities.Mistletoe increased the amount, quality, and diversity of organic matter input beneath the host canopy, directly through its nutrient‐rich litter and indirectly through a reduction in host litterfall and an increase in bird‐derived debris. All these effects gave rise to enriched hotspots able to support larger and more functionally even soil microbial communities beneath parasitized hosts, the effects of which were accentuated after host death.We conclude that mistletoe, together with the biotic interactions it mediates, plays a key role in intensifying soil resource availability, regulating the functional evenness, abundance, and spatial distribution of soil microbial communities.

Climate change and atmospheric nitrogen (N) deposition on drylands are greatly threatening these especially vulnerable areas. Soil biocrust-forming lichens in drylands can provide early indicators of these disturbances and play a pivotal role, as they contribute to key ecosystem services. In this study, we explored the effects of different long-term water availability regimes simulating climate changes and their interaction with N addition on the physiological response of the soil lichen Cladonia rangiferina. Three sets of this lichen were subjected to control, reduced watering, and reduced watering and N addition (40 kg NH4NO3 ha−1 year−1) treatments for 16 months. Finally, all samples were subjected to daily hydration cycles with N-enriched water at two levels (40 and 80 kg NH4NO3 ha−1 year−1) for 23 days. We found that reduced watering significantly decreased the vitality of this lichen, whereas N addition unexpectedly helped lichens subjected to reduced watering to cope with stress produced by high temperatures. We also found that long-term exposure to N addition contributed to the acclimation to higher N availability. Overall, our data suggest that the interactions between reduced watering and increased N supply and temperature have an important potential to reduce the physiological performance of this soil lichen.

Mediterranean Basin ecosystems, their unique biodiversity, and the key services they provide are currently at risk due to air pollution and climate change, yet only a limited number of isolated and geographically-restricted studies have addressed this topic, often with contrasting results. Particularities of air pollution in this region include high O3 levels due to high air temperatures and solar radiation, the stability of air masses, and dominance of dry over wet nitrogen deposition. Moreover, the unique abiotic and biotic factors (e.g., climate, vegetation type, relevance of Saharan dust inputs) modulating the response of Mediterranean ecosystems at various spatiotemporal scales make it difficult to understand, and thus predict, the consequences of human activities that cause air pollution in the Mediterranean Basin. Therefore, there is an urgent need to implement coordinated research and experimental platforms along with wider environmental monitoring networks in the region. In particular, a robust deposition monitoring network in conjunction with modelling estimates is crucial, possibly including a set of common biomonitors (ideally cryptogams, an important component of the Mediterranean vegetation), to help refine pollutant deposition maps. Additionally, increased attention must be paid to functional diversity measures in future air pollution and climate change studies to establish the necessary link between biodiversity and the provision of ecosystem services in Mediterranean ecosystems. Through a coordinated effort, the Mediterranean scientific community can fill the above-mentioned gaps and reach a greater understanding of the mechanisms underlying the combined effects of air pollution and climate change in the Mediterranean Basin.