European Coasts Research Articles

Facultative endosymbionts of aphid populations from coastal dunes of the North Sea

Aphids establish symbiotic associations with a diverse assemblage of mutualistic bacteria. Some of them are not required for the host’s survival but still have a crucial impact on the biology and ecology of their host. Facultative symbionts may modify important host-life-history traits and affect the interactions of aphids with other members of the community. So far several species of aphid have been reported to occur in coastal dunes. Given the extreme environmental conditions of this type of habitat and the wide distribution along the European coast of some aphid species, these aphids would be expected to show variation in their facultative endosymbionts. However, there is currently no information available for these species. To address this question, we collected specimens from different populations of aphids (i.e. Schizaphis rufula, Laingia psammae and Rhopalosiphum padi) associated with the dune grass Ammophila arenaria in several locations of the North and the Irish Sea. By means of specific diagnostic PCR’s we checked for the presence of facultative bacterial endosymbionts in these populations. Results of this explorative assessment showed variation in the endosymbiont community according to species and location. All populations sampled along the North Sea coast were associated with the facultative endosymbiont Serratia symbiotica. Hamiltonella defensa was only detected in some specimens coming from the population in Het Zwin, Belgium. Regiella insecticola and the γ-protobacteria X-type were only found associated with the population of Schizaphis rufula in De Panne, Belgium. Although further experiments are necessary to characterize the nature of these symbiotic relationships, our correlation analyses showed a significant co-occurrence of S. symbiotica with H. defensa and R. insecticola with X-type protobacteria suggesting reciprocal regulatory functions. No significant correlation was detected between the number of mummies (i.e. carcasses of aphids parasitized by wasps) and the occurrence of bacterial symbionts. The potential role of these symbionts in coastal dune ecosystems is discussed.

Speciation history of European (Anguilla anguilla) and American eel (A.rostrata), analysed using genomic data.

Speciation in the ocean could differ from terrestrial environments due to fewer barriers to gene flow. Hence, sympatric speciation might be common, with American and European eel being candidates for exemplifying this. They show disjunct continental distributions on both sides of the Atlantic, but spawn in overlapping regions of the Sargasso Sea from where juveniles are advected to North American, European and North African coasts. Hybridization and introgression are known to occur, with hybrids almost exclusively observed in Iceland. Different speciation scenarios have been suggested, involving either vicariance or sympatric ecological speciation. Using RAD sequencing and whole-genome sequencing data from parental species and F1 hybrids, we analysed speciation history based on the joint allele frequency spectrum (JAFS) and pairwise sequentially Markovian coalescent (PSMC) plots. JAFS supported a model involving a split without gene flow 150,000-160,000 generations ago, followed by secondary contact 87,000-92,000 generations ago, with 64% of the genome experiencing restricted gene flow. This supports vicariance rather than sympatric speciation, likely associated with Pleistocene glaciation cycles and ocean current changes. Whole-genome PSMC analysis of F1 hybrids from Iceland suggested divergence 200,000 generations ago and indicated subsequent gene flow rather than strict isolation. Finally, simulations showed that results from both approaches (JAFS and PSMC) were congruent. Hence, there is strong evidence against sympatric speciation in North Atlantic eels. These results reiterate the need for careful consideration of cases of possible sympatric speciation, as even in seemingly barrier-free oceanic environments palaeoceanographic factors may have promoted vicariance and allopatric speciation.

EU Operational Powers and Legal Protection. A Legal Theory Perspective on the Operational Powers of the European Border and Coast Guard

For the first time in its history the EU is in the process of acquiring significant and genuine permanent operational powers. A new Regulation on the European Border and Coast Guard provides Frontex with a permanent corps of 10,000 border guards of which 3,000 will be EU agents, its own equipment and its own competences to intervene along the borders of the EU and beyond. The operational powers will allow the EU to directly intervene physically in tangible reality. This article argues that the conferral of operational powers on the EU poses a risk to individual legal protection. Because once authorities have acquired operational powers of a certain extent and quality, they can afford to act against or without the law by simply overpowering or eluding the legal mechanisms that normally constrain the exercise of public power. So far Members of the European Parliament and academics critical of Frontex and the new Regulation have overlooked this issue and concentrated exclusively on how to legally constrain the exercise of operational powers. The article addresses this blind spot by examining whether and how public law should place legal constraints not only on the exercise but also on the build-up of operational powers.

Frontex: From Coordinating Controls to Combating Crime

The last few years have seen the European Border and Coast Guard Agency (“Frontex”) grow ever more central to European efforts to control the external borders. The Agency moved from a merely coordinating and supporting role to a much more operational one. Frontex now engages in tasks running the gamut from surveying the borders and returning irregular migrants to combating criminal activity. To make this possible, the financial and personnel resources at the disposal of the Agency were increased substantially. This article first sheds some light on the historical background of the Agency. It then traces the successive mandate revisions and the growth in power they entailed. The article then examines how crime fighting was introduced into Frontex’ mandate, before analysing the Agency’s contribution to combating criminal activity and its implications.

LEGAL NATURE OF THE WORKING ARRANGEMENTS OF THE EUROPEAN BORDER AND COAST GUARD AGENCY

The article analyzes the content and the procedure for concluding working arrangements of the European Border and Coast Guard Agency (FRONTEX). It is noted that, taking into account its legal personality, the Agency's partners may be third countries and international organizations with which it has the right to enter into the relevant arrangements on its own. The author draws attention to the fact that in FRONTEX’s enforcement practices there are different names of concluded agreements, but in form and content they are all working arrangements. The procedure for the negotiation and conclusion of working arrangements is analyzed and it is concluded that the EU pays serious attention to the legal instrument under consideration for cooperation with international partners. In particular, it is noted that the Commission and the Member States play a significant role in the harmonization of the text of the agreement. It is proposed to empower the European Parliament by granting it the right of prior approval of the final text of the document. The content of working arrangements concluded with third countries and international organizations is analyzed in detail and the following features are established: 1) since 2012, there is a trend to consolidate the principle of respect for human rights in agreements with third countries; 2) the agreements may contain provisions on the financial aspects of cooperation between the parties; 3) for the first time in the working arrangement with Kosovo, the provision on the exchange of personal data is enshrined; 4) certain working arrangements provide for the possibility of suspend of the agreement until the dispute is settled between the parties. It is concluded that the working arrangements are not international public treaties, because: 1) agreements with third countries directly establish that such documents do not create international obligations; 2) the agency is not endowed with the international legal personality to conclude agreements on behalf of the Union under the procedure provided for in Art. 218 TFEU; 3) the text of the document mainly contains non-binding wording. The author proposes to consider working arrangements as acts of soft law, the implementation of which leads to legal consequences. Cooperation between FRONTEX and third countries and international organizations is not limited by working arrangements and may be expanded by additional agreements.

Wind Farms and Climate Change in Eurasia and America

The study of the natural phenomenon - global warming in the northern hemisphere of the planet was carried out on the basis of the definition of American climatologist Wallace Broker, which implies an increase in the average temperature of the lower layers of the atmosphere and seas associated with the industrialization of the economy. That is, these are climatic changes that have arisen under the influence of anthropogenic factors. GISMETEO RF weather data and weather maps of Eurasia and North America were also used. The main and determining factor is the massive use of wind power on the paths of cyclones. The interaction of wind farms installed on the Atlantic coast of Europe and Atlantic cyclones is simulated. The results are presented as a synoptic map for Europe.

К вопросу о датировке ранних крепостных стен боспорского города Тиритака

According to the results of the latest author’s research, Bosporan city Tyritake was one of early and relatively big centres of the European coast of the Cimmerian Bosporus. At the turn of the last two decades of the 6th century BC after the fire associated with a war cataclysm had broken out, the city was surrounded by a relatively solid fortification walls on an area of at least 5 hectares.

A Pacific oyster invasion transforms shellfish reef structure by changing the development of associated seaweeds

Biological invasions are reshaping coastal ecosystems across the world. However, understanding the significance of such invasions is often hampered by the lack of process-based research, resulting in a limited mechanistic comprehension of novel ecological interactions and their consequences. The Pacific oyster (Crassostrea gigas) has invaded European coasts, resulting in an astonishing transformation of the intertidal shellfish reef communities in the Wadden Sea; from reefs constructed by blue mussels only (Mytilus edulis) to mixed reefs dominated by oysters. Shellfish reefs structure the marine vegetation on soft bottoms by accumulating seaweeds. Nevertheless, assessments of the consequences of the oyster take-over have almost exclusively focused on effects on associated fauna. By constructing small-scale reefs dominated by blue mussels or oysters and following the development of seaweeds over summer, we demonstrated that oysters promoted bloom-forming green algae communities with low primary biomass and low habitat complexity. In contrast, blue mussels promoted the development of meadow-like communities dominated by habitat forming brown seaweeds of the genus Fucus, with high primary biomass and high habitat complexity. An additional field survey showed that increasing numbers of Pacific oysters on a recently invaded natural blue mussel reef significantly decreased the development of the Fucus meadow in spring. Our results indicate that the invasion of oysters may have effects on the structure and function of intertidal reef-communities by changing energy flow and habitat-function.

Likely and High-End Impacts of Regional Sea-Level Rise on the Shoreline Change of European Sandy Coasts Under a High Greenhouse Gas Emissions Scenario

Sea-level rise (SLR) is a major concern for coastal hazards such as flooding and erosion in the decades to come. Lately, the value of high-end sea-level scenarios (HESs) to inform stakeholders with low-uncertainty tolerance has been increasingly recognized. Here, we provide high-end projections of SLR-induced sandy shoreline retreats for Europe by the end of the 21st century based on the conservative Bruun rule. Our HESs rely on the upper bound of the RCP8.5 scenario “likely-range” and on high-end estimates of the different components of sea-level projections provided in recent literature. For both HESs, SLR is projected to be higher than 1 m by 2100 for most European coasts. For the strongest HES, the maximum coastal sea-level change of 1.9 m is projected in the North Sea and Mediterranean areas. This translates into a median pan-European coastline retreat of 140 m for the moderate HES and into more than 200 m for the strongest HES. The magnitude and regional distribution of SLR-induced shoreline change projections, however, utterly depend on the local nearshore slope characteristics and the regional distribution of sea-level changes. For some countries, especially in Northern Europe, the impacts of high-end sea-level scenarios are disproportionally high compared to those of likely scenarios.

Prey size selection in invasive (Hemigrapsus sanguineus and H. takanoi) compared with native (Carcinus maenas) marine crabs

AbstractIntroductions of predators can have strong effects on native ecosystems and knowledge of the prey size selection of invasive predators is pivotal to understand their impact on native prey and intraguild competitors. Here, we investigated the prey size selection of two invasive crabs (Hemigrapsus sanguineus and Hemigrapsus takanoi) recently invading European coasts and compared them with native shore crabs (Carcinus maenas) which are known to feed on similar prey species. In laboratory experiments, we offered different size classes of native blue mussels (Mytilus edulis) to different size classes of the crab species in an effort to identify the respective prey size preferences and potential overlap in prey size range of native and invasive crabs. In all three species, the preferred prey size increased with crab size reflecting general predator–prey size relationships. Prey size preference did not differ among the crab species, i.e. crabs showed similar mussel size preference in relation to carapace width. Given that additional morphological measurements showed that both of the invasive crab species have much larger claws relative to their body size compared with the native species, this finding was surprising and may relate to differential claw morphologies or structural strength. These results suggest that the invasive crabs exert predation pressure on the same size classes of native mussels as the native crabs, with potential effects on mussel population dynamics due to the high densities of the invaders. In addition, the overlap in prey size range is likely to result in resource competition between invasive and native crabs.

Differential response of biomarkers in the native European flat oyster Ostrea edulis and the non-indigenous Pacific oyster Crassostrea gigas co-exposed to cadmium and copper

Marine pollution favours the invasion and spreading of non-indigenous species in their new habitats. Comparative advantages of introduced and potentially invasive bivalves over their native counterparts might be reflected in better ability to cope with chemical stressors.The objective of the present study was to investigate differences in the biochemical stress response to Cd and Cu between the flat oyster Ostrea edulis (Linnaeus, 1758), native to European coasts, and its non-indigenous congener, the Pacific oyster Crassostrea gigas (Thunberg, 1793), recently detected in the eastern Adriatic. Oysters were co-exposed in vivo to sub lethal concentrations of metals. The stress response of two oyster species was evaluated using biomarkers of neurotoxicity (acetylcholinesterase, AChE), detoxification (metallothioneins, MTs) and oxidative stress (glutathione S-transferase, GST; lipid peroxidation, LPO). Biomarkers related to oxidative stress response were the most informative and suggested comparably lower capability of the non-indigenous C. gigas for handling pro-oxidant conditions after Cu exposure.Overall, the species-specific biomarker alterations displayed by oysters exposed simultaneously to the same experimental conditions represent the first evidence of differences between these two bivalves in the ability to overcome the chemically induced stress. The present research highlights the need for monitoring of biochemical features that might determine the behaviour of oysters in newly colonised habitats under environmental challenges foreseen in the upcoming years.

CSOs and EU Border Management: Cooperation or Resistance? The Case of Frontex Consultative Forum

The so-called European migrant or refugee crisis, started in 2015, has marked the climax of an increasing European tension on the management of the external borders, tension that had been building up since the turn of the century. In this particularly turbulent period, civil society organizations (CSOs) lobbying for human and migrant rights have expanded their presence not only operatively at the land and sea borders of the European Union (EU) but also at the EU governance level. With the growing importance of agencies in the EU executive space in terms of competences and resources (i.e., agencification), advocacy groups have started to direct their advocacy efforts toward EU agencies, particularly in the Area of Freedom Security and Justice. The most controversial EU agency in this scenario is the 13-year-old agency Frontex, now called European Border and Coast Guard Agency, which is also where the presence of CSOs has become more substantial in terms of competences and ability to access information on the operational and strategic activity of the agency. The aim of this article is to establish how this relationship between Frontex and CSOs has developed over time and what has been the impact of this relationship on the agency on fundamental rights matters. This study addresses these two issues by, first, analyzing the CSOs represented within Frontex Consultative Forum (CF) on fundamental rights, their aims and lobbying strategies vis-à-vis Frontex; second, the evolution of their relationship with the agency and the rationale of their permanence within the CF; and, last, their impact on Frontex’s understanding of fundamental rights. Considerations on advocacy activity outside of the CF are also presented by stressing the difference in ideology between organizations that decided to advocate for fundamental rights from within or outside Frontex.

The new European border and coast guard agency: pooling sovereignty or giving it up?

ABSTRACTIn 2016, the European Parliament and the Council adopted a legislative act creating and regulating a new European Border and Coast Guard Agency. Its Article 19 states that – should a Member State’s failure to control its own borders jeopardize the collective effort to monitor the external borders of the Schengen Area – the new Agency could take over the management of border control operations in that Member-State. This transfer of power begs a crucial question regarding EU’s conflict of sovereignties. First, this article identifies three paradigmatic conceptions of sovereignty (traditional, post-sovereignist, and post-traditional), and, second, it applies them to our case study to assess which conception provides the best explanatory model. We eventually argue that the post-traditional perspective proves the fittest to capture the current integration of the EU’s external border management, best described as an institutional bricolage (by contrast with a grand architectonic design).

The relationship between the moon cycle and the orientation of glass eels (Anguilla anguilla) at sea.

Links between the lunar cycle and the life cycle (migration patterns, locomotor activity, pulses in recruitment) of the European eel (Anguilla anguilla) are well documented. In this study, we hypothesized that the orientation of glass eels at sea is related to the lunar cycle. The European eel hatches in the Sargasso Sea and migrates across the Atlantic Ocean towards Europe. Upon reaching the continental shelf, the larvae metamorphose into glass eels and migrate up the estuaries, where some individuals colonize freshwater habitats. How glass eels navigate pelagic waters is still an open question. We tested the orientation of 203 glass eels in a transparent circular arena that was drifting in situ during the daytime, in the coastal Norwegian North Sea, during different lunar phases. The glass eels swimming at sea oriented towards the azimuth of the moon at new moon, when the moon rose above the horizon and was invisible but not during the other moon phases. These results suggest that glass eels could use the moon position for orientation at sea and that the detection mechanism involved is not visual. We hypothesize a possible detection mechanism based on global-scale lunar disturbances in electrical fields and discuss the implications of lunar-related orientation for the recruitment of glass eels to estuaries. This behaviour could help glass eels to reach the European coasts during their marine migration.

К вопросу о видовой принадлежности Spio (Annelida, Spionidae) из Азово-Черноморского бассейна

Для Чёрного моря указано три вида полихет рода Spio Fabricius, 1785 ― Spio decorata Bobretzky, 1870; Spio filicornis (Müller, 1776); Spio multioculata (Rioja, 1918); для Азовского ― один [Spio filicornis (Müller, 1776)]. S. multioculata известен лишь для Прибосфорского района и берегов Румынии. Вид S. decorata описан в 1870 г. Н. В. Бобрецким из материалов, собранных в районе Севастополя. S. filicornis впервые отмечен у берегов Крыма в районе Карадага К. А. Виноградовым в 1931 г. В дальнейшем полихет рода Spio, найденных в северо-западной части Чёрного моря, у берегов Крыма и Кавказа, у берегов Болгарии, а также в Азовском море, определяли как Spio filicornis. Вид S. decorata был забыт, несмотря на то, что его регистрировали и в Средиземном море, и у побережья Европы. Для уточнения видовой принадлежности Spio использованы полихеты из сборов макрозообентоса в Чёрном и Азовском морях в рейсах НИС «Профессор Водяницкий», а также из б. Севастопольская, являющейся типовым местонахождением Spio decorata. Отбор донных осадков осуществляли с помощью дночерпателя «Океан-25» (S = 0,25 м²). Грунт промывали через сита с наименьшим диаметром 1 мм. В б. Севастопольская сбор макрозообентоса проводили ручным водолазным дночерпателем (S = 0,1 м²). Личинок полихет отбирали ежемесячно в б. Севастопольская сетью Джеди. Обработку живого материала проводили под микроскопом МБС-9; личинок Spio отсаживали и подращивали до появления характерных видовых признаков. В работе дано морфологическое описание собранных Spio, приведены фотографии и рисунки их характерных признаков. Установлено, что морфологические характеристики рассмотренных полихет рода Spio как из Чёрного, так и из Азовского морей соответствуют описанному в 1870 г. виду Spio decorata Bobretzky, 1870. Отмечено, что S. decorata широко распространён в северо-западной части Чёрного моря, где зарегистрирован на глубине до 38 м. Вид встречается на различных грунтах, но предпочитает слегка заиленный ракушечник с песком. Наибольшая встречаемость S. decorata (38 %) отмечена на глубине 20–30 м, а плотность ― на глубине менее 20 м. Максимальная плотность S. decorata (556 экз.·м−2) зарегистрирована в 2010 г. в северо-западной части Чёрного моря на глубине 19 м. Личинки S. decorata в планктоне встречались с марта по октябрь при температуре воды от +8 до +26 °C. То, что размножение данного вида в Чёрном море происходит в весенне-летний сезон, а также его экологические особенности свидетельствуют о его теплолюбивости, что отличает S. decorata от S. filicornis, обитающего в арктических водах. Можно предположить, что предыдущие указания о нахождении полихеты S. filicornis в Азово-Черноморском бассейне на самом деле относятся к виду S. decorata.

Higher probability of compound flooding from precipitation and storm surge in Europe under anthropogenic climate change.

In low-lying coastal areas, the co-occurrence of high sea level and precipitation resulting in large runoff may cause compound flooding (CF). When the two hazards interact, the resulting impact can be worse than when they occur individually. Both storm surges and heavy precipitation, as well as their interplay, are likely to change in response to global warming. Despite the CF relevance, a comprehensive hazard assessment beyond individual locations is missing, and no studies have examined CF in the future. Analyzing co-occurring high sea level and heavy precipitation in Europe, we show that the Mediterranean coasts are experiencing the highest CF probability in the present. However, future climate projections show emerging high CF probability along parts of the northern European coast. In several European regions, CF should be considered as a potential hazard aggravating the risk caused by mean sea level rise in the future.

Development and validation of eDNA markers for the detection of Crepidula fornicata in environmental samples

The invasive Crepidula fornicata caused major problems along the European Atlantic coast, especially in France and Netherlands where high densities leads on changes in the habitat, disturb native marine wildlife as well as it originates competition for space and food. Despite its dangerous invasive nature, regular monitoring to alert about its presence in risk areas, like the south Bay of Biscay (Spain and south France), is not done yet. Here, we developed a species-specific marker to detect the presence of C. fornicata in environmental samples (eDNA) of seawater. The novel C. fornicata specific primers amplified a region of 239 bp within the COI gen. We employed this tool to check its presence in 6 estuaries of the Cantabrian Sea, an area comprised between the Spanish and French limits of the previously reported presence of this limpet in the south Bay of Biscay. The presence of C. fornicata was confirmed in A Coruña (Galicia, Spain), Eo and Villaviciosa estuaries (Asturias, Spain) while it was not detected in Santander, Bilbao (Spain), and Bayonne (France). This new method to detect C. fornicata could be easily implemented in regular monitoring to prevent and manage future invasions of this species.

Revision of the Genus Schizoretepora (Bryozoa, Cheilostomatida) from the Atlantic-Mediterranean region

We examined the type specimens and historical collections holding puzzling Atlantic and Mediterranean material belonging to the genus Schizoretepora Gregory, 1893. We performed a detailed study of the colonial characters and re-describe the resulting species and those that have rarely been found or have poor original descriptions. As a result of this revision, nine species are found in the northeast Atlantic and Mediterranean. Six of them are re-described and illustrated: S. aviculifera (Canu & Bassler, 1930), S. calveti d’Hondt, 1975, S. imperati (Busk, 1884), S. sp. nov.? (= S. imperati sensu O’Donoghue & de Watteville 1939) (in open nomenclature, specimen lacks ovicells), S. pungens (Canu & Bassler, 1928) and S. solanderia (Risso, 1826). For S. dentata (Calvet, 1931), no material remains; furthermore, S. hassi Harmelin, Bitar & Zibrowius, 2007 and S. serratimargo (Hincks, 1886) have recently been described and redescribed, respectively. This new arrangement attains a coherent geographical distribution: S. imperati seems restricted to the eastern Atlantic, S. dentata and S. calveti are deepwater species from Atlantic islands, S. pungens and S. aviculifera dwell on the African coasts of the Western Mediterranean, S. hassi and S. sp. nov.? (=S. imperati sensu O’Donogue & de Wateville 1939) are confined to the Eastern Mediterranean, and S. solanderia and S. serratimargo live on the European coasts of the Mediterranean.

Signatures of selection for bonamiosis resistance in European flat oyster (Ostrea edulis): New genomic tools for breeding programs and management of natural resources.

The European flat oyster (Ostrea edulis) is a highly appreciated mollusk with an important aquaculture production throughout the 20th century, in addition to playing an important role on coastal ecosystems. Overexploitation of natural beds, habitat degradation, introduction of non‐native species, and epidemic outbreaks have severely affected this important resource, particularly, the protozoan parasite Bonamia ostreae, which is the main concern affecting its production and conservation. In order to identify genomic regions and markers potentially associated with bonamiosis resistance, six oyster beds distributed throughout the European Atlantic coast were sampled. Three of them have been exposed to this parasite since the early 1980s and showed some degree of innate resistance (long‐term affected group, LTA), while the other three were free of B. ostreae at least until sampling date (naïve group, NV). A total of 14,065 SNPs were analyzed, including 37 markers from candidate genes and 14,028 from a medium‐density SNP array. Gene diversity was similar between LTA and NV groups suggesting no genetic erosion due to long‐term exposure to the parasite, and three population clusters were detected using the whole dataset. Tests for divergent selection between NV and LTA groups detected the presence of a very consistent set of 22 markers, located within a putative single genomic region, which suggests the presence of a major quantitative trait locus associated with B. ostreae resistance. Moreover, 324 outlier loci associated with factors other than bonamiosis were identified allowing fully discrimination of all the oyster beds. A practical tool which included the 84 highest discriminative markers for tracing O. edulis populations was developed and tested with empirical data. Results reported herein could assist the production of stocks with improved resistance to bonamiosis and facilitate the management of oyster beds for recovery production and ecosystem services provided by this species.

Afforestation reduces cyclone intensity and precipitation extremes over Europe

Extratropical cyclones are the dominant weather pattern in the midlatitudes and cause up to 80% of precipitation extremes in some regions of Europe with a large societal and economical impact. Using a regional climate model and a cyclone-tracking algorithm, we study how idealized deforestation and afforestation of Europe affect long-term changes in the number and intensity of cyclones, and their effects on precipitation. The number of cyclones over Europe is smaller for afforestation compared to deforestation, with differences starting from 10% in regions near the west European coast and increasing towards the east to reach 80%. This decrease is caused by the larger surface roughness in afforestation. The winter precipitation extremes are considerably reduced with afforestation, without a large decrease in mean precipitation because of the balancing effect of increased weak and moderate precipitation. The mean precipitation increases over central and southern Europe as a result of the summer precipitation increase caused by larger evapotranspiration and access to deeper soil moisture in the presence of trees. These different region-specific effects of afforestation are generally positive and could provide an important mitigation tool in a changing climate.