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This work analyzes the evolution of the large shifting dune included in the Corrubedo Natural Park from 1956 until the present day. The analysis was carried out using aerial images, orthophotographs, topographic surveys and LiDAR (Light Detection and Ranging) data. Variations were analyzed in terms of four different aspects: evolution of pathways in each period, changes in the position of the mobile dune front and the degree of vegetation cover, all between 1956 and 2017; and variations in elevation and volume of the dune system between 2001 and 2015. To analyze these aspects, geospatial and geostatistical techniques were employed, which revealed that the dune front had undergone two different phases: one until the 1980s, with a mean seaward advance of 32 m and another one between the 1980 s and 2017, when the front prograded to the continent, with an approximate mean advance of 82 m. Loss of volume, related to the expansion of the mobile dune towards the north, was confirmed in this sector. It is evident that these changes are closely linked to anthropic influence, due to sand extraction until the early 1990s and, more recently, due to an increase in the number of visitors to the Natural Park. The results obtained highlight the need to carry out detailed studies to understand the evolution of this system and to prevent further damage in the future. Moreover, based on these analyses, a strategy to improve coastal and environmental management in the Corrubedo Natural Park could be designed. [ABSTRACT FROM AUTHOR]

The Natura 2000 network is an ambitious European project aimed at nature conservation. Nevertheless, the identification and delimitation of habitats is a complex task and simultaneously essential for correct ecosystem management. In this study we compared the current habitat delimitation and designation and the results produced by Geographic Information Systems (GIS) and geochemical proxies for the categorization of four coastal lakes in Galicia (NW Iberian Peninsula). The findings reveal important errors in the delimitation/designation. The first error is the designation of all four lakes as Coastal lagoons (habitat 1150), when geochemical data indicate that two of these lakes were always freshwater lakes and should consequently be classified as Natural eutrophic lakes (habitat 3150). Another error is of conceptual origin, because the lakes comprise a unique functional system composing of different environmental units (e.g., open water or aquatic vegetation). Subdivision into different habitats is therefore meaningless for units of negligible surface area. In addition, the designation of some habitats is very dubious according to the available data. Finally, notable changes in relation to the temporal changes of wetlands were observed. Thus, the area occupied by aquatic macrophytes increased greatly at the expense of open waters, and the increase was also reflected in the alluvial forest. This last finding indicates the importance of updating the state of Natura 2000 network in Galicia to improve habitat management. [ABSTRACT FROM AUTHOR]

Due to the limited number of studies on phytoremediation using native tree species in tropical soils, the aim was to identify new phytoremediator species from tropical climate with the purpose of promoting an increase in the diversity of tropical native trees used in phytoremediation projects. Seven native tree species from Brazil were selected: Cedrela fissilis, Handroanthus serratifolius, Copaifera langsdorffii, Hymenaea courbaril, Mimosa caesalpiniifolia, Cecropia sp. and Myracrodruon urundeuva. Seedlings of these species were planted in pots with an unpolluted Arenosol, and then spiked with 60, 100 and 500 mg kg−1 Cu. Height and stem diameters were measured over 60 days. Biomass and total Cu concentration were determined in leaves, stem and roots. Copper in bulk soils and rhizospheres was analyzed by a sequential extraction method. All species accumulated high concentration of Cu in roots (>300 mg kg−1), so they could be used as phytostabilizators for this metal. Copper mobilization increased in the rhizospheres, but it was mostly absorbed by roots. Cecropia sp., M. urundeuva and C. langsdorffii are hyperaccumulators of Cu (>300 mg kg−1 in shoots), so they are potential phytoextractor species. This study evidence the potential of seven tree species native from tropical regions for phytostabilizing copper-polluted soils. [ABSTRACT FROM AUTHOR]

The mobilisation of potentially harmful chemical constituents in wildfire ash can be a major consequence of wildfires, posing widespread societal risks. Knowledge of wildfire ash chemical composition is crucial to anticipate and mitigate these risks. Here we present a comprehensive dataset on the chemical characteristics of a wide range of wildfire ashes (42 types and a total of 148 samples) from wildfires across the globe and examine their potential societal and environmental implications. An extensive review of studies analysing chemical composition in ash was also performed to complement and compare our ash dataset. Most ashes in our dataset had an alkaline reaction (mean pH 8.8, ranging between 6 and 11.2). Important constituents of wildfire ash were organic carbon (mean: 204 g kg -1 ), calcium, aluminium, and iron (mean: 47.9, 17.9 and 17.1 g kg -1 ). Mean nitrogen and phosphorus ranged between 1 and 25 g kg -1 , and between 0.2 and 9.9 g kg -1 , respectively. The largest concentrations of metals of concern for human and ecosystem health were observed for manganese (mean: 1488 mg kg -1 ; three ecosystems > 1000 mg kg -1 ), zinc (mean: 181 mg kg -1 ; two ecosystems > 500 mg kg -1 ) and lead (mean: 66.9 mg kg -1 ; two ecosystems > 200 mg kg -1 ). Burn severity and sampling timing were key factors influencing ash chemical characteristics like pH, carbon and nitrogen concentrations. The highest readily dissolvable fractions (as a % of ash dry weight) in water were observed for sodium (18 %) and magnesium (11.4 %). Although concentrations of elements of concern were very close to, or exceeded international contamination standards in some ashes, the actual effect of ash will depend on factors like ash loads and the dilution into environmental matrices such as water, soil and sediment. Our approach can serve as an initial methodological standardisation of wildfire ash sampling and chemical analysis protocols., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Seabird colonies exert a strong influence on coastal ecosystems, increasing soil nitrogen bioavailability and modifying plant communities. Previous studies have evidenced that increased N in soils leads to changes in plant cell wall composition; however, this effect has not been assessed in seabird colonies. The main objective of this study was to determine the influence of seabird colonies on nitrogen, cellulose and lignin content in cell walls. For this purpose, analyses were performed on droppings, soils and three native plant species (Armeria pubigera, Armeria pungens and Corema album) growing in yellow-legged gull colonies. The results showed that N excreted by yellow-legged gull is assimilated by plants, increases N content in plant tissues and reduces cellulose and lignin synthesis, therefore potentially altering plant resistance against phytoparasites., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Seabirds form large colonies during the reproductive period, producing substantial changes in coastal ecosystems. The present study quantifies the amount of N and P deposited in colonies of yellow-legged gull (Larus michahellis) in the Atlantic Islands of Galicia National Park (AINP). Based on the composition of droppings, the amount of total N (TN), total P (TP) and bioavailable P (Pbio) deposited directly on the area occupied by the colony was determined. In addition, the amount of NH 3 released into the atmosphere was also estimated by applying a bioenergetic model. The results indicated that 5.35 t total N, 3.35 t total P and 1.24 t bioavailable P are deposited in the colony annually. The archipelagos that received the greatest amount of nutrients were the Cíes Islands (2.37 t TN y -1 , 1.48 t TP y -1 , 0.55 t Pbio y -1 ), Sálvora (1.94 t TN y -1 , 1.22 t TP y -1 , 0.55 t Pbio y -1 ) and Ons (1.04 t TN y -1 , 0.65 TP y -1 , 0.24 t Pbio y -1 ). Rainwater from the colonies showed higher values of nutrients than in the control plot, possibly also due to gull influence. Therefore, the yellow-legged gull colony seems to be the most important source of nutrients at a local level, exerting a clear influence on the N and P cycles in this National Park. Another aspect worth taking into consideration is that increased N and P bioavailability may have a negative effect on the conservation of rare or threatened habitats and species by promoting the expansion of non-native ruderal species., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

The Ría de Ortigueira is an environmentally well conserved; however, the sediments show high concentrations of toxic elements. In some zones, the concentrations of Ni (60-1080 mg kg -1 ) and Cr (9-567 mg kg -1 ) were extremely high, while the concentrations of other toxic elements were within normal ranges. PCA revealed that metal enrichment was due to dumping of waste sludge from a peridotite mine. The study of marine currents showed that the exit of the contaminated waste towards the external zone is restricted by the low energy of the residual currents, and the sludge therefore remains trapped in the internal zones. The potential ecological risk was moderate for all areas of the ría, reaching high values close to the mouth of the river Landoi. Finally, geochemical fractioning showed that most of the metals are associated with Fe oxyhydroxides which can become unstable and release adsorbed or coprecipitated metals, especially Ni., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Technosols created to reclaim degraded soils is a promising solution that needs further research. The objectives of the study were: i) to create a Technosol with a very high capacity to immobilize copper from mining, ii) to assess the capacity of the Technosol to immobilize copper after planting two tropical native tree species, and iii) to analyse the capacity of the native trees for extracting copper from polluted soils. Myracrodruon urundeuva (aroeira) and Cedrela fissilis (pink cedar) were planted in pots with Technosol spiked with copper at concentrations of 125, 1525 and 3050 mg Cu kg -1 . Height and stem diameter were measured over 90 days. Biomass and Cu concentration in leaves, stem and roots were determined. Copper was analysed in soils by sequential extraction, as well as in leached water. The Technosol showed a very high capacity to immobilize copper, since 60-80% of the added copper was strongly retained in the soil, mainly by bentonite and carbonates. The Technosol with trees showed the same capacity to immobilize copper as the control, since concentration in shoots was higher than 300 mg Cu kg -1 and concentration in roots was even higher. These results show that Technosol and both species are useful tools to immobilize copper in polluted soils. Further studies are necessary to determine the total capacity of these trees to immobilize and/or extract copper in the long term and under field conditions., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Marine-derived nutrients are known accumulate in seabird breeding colonies due to the deposition of nutrient-rich biological materials, thus greatly altering the functioning and dynamics of these terrestrial ecosystems. Here we present the results of a sampling survey carried out during three years in yellow-legged gull colonies in the Atlantic Islands of Galicia National Park (NW Spain) with the aim of evaluating the influence of the colonies on the accumulation of trace elements, including micronutrients (Cu, Zn, Se, Co, Mo, Ni) and toxic elements (Cr, Cd, Hg, Pb, As, Ag), in the surrounding environments. For this purpose, we analysed samples of biological materials produced by the seabirds (pellets, excrement, feathers, eggs) and of soil, plants and inland water from several different subcolonies and control zones without seabirds. The concentrations of most of the elements were higher in excrement and pellets (mean values: Zn: 152, As: 50 mg kg -1 , Cd: 6, Co: 5 mg kg -1 ) than in feathers and eggs. The flow of trace elements into the breeding colonies, considering only the excrement, revealed a very high level of trace element deposition for a supposedly pristine environment (Zn: 2667, Cd: 70, Cu: 315, As: 64 g ha -1 ). The total concentrations of trace elements in soil were consistent with the long-term impact of the seabirds. Thus, the values in areas which this impact was greatest were significantly higher than in the control zones, particularly considering the most labile geochemical fractions of the soil. The concentrations of some elements (i.e. Co, As, Cd) were also higher in the inland waters in the colonies than in control zones. Finally, the concentration of trace elements in plants varied depending on the species and element considered., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Seabird colonies drastically transform the sites that they inhabit. Although the influence of seabirds on nutrient cycling has been investigated in numerous studies, the effects on trace elements has scarcely been considered. In this study, we determined the total contents of 9 trace elements in biomaterials (excrement, pellets, feathers and eggs) and soils in relation to the presence the Yellow-legged gull Larus michahellis. The concentrations of Zn, Cu and As were particularly high in the pellets and excrement. The total contents of the trace elements were significantly higher in the soils in the sub-colonies in which Yellow-legged gulls predominate than in soil from the control zone (with no gulls). The difference was even higher for the most reactive geochemical fractions. We observed that the oxidizable fraction was the most relevant fraction for almost all trace elements, indicating the importance of organic matter in trace element retention in sandy soils., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Mangrove forests play an important role in biogeochemical cycle of C, storing large amounts of organic carbon. However, these functions can be controlled by the high spatial heterogeneity of these intertidal environments. In this study were performed an intensive sampling characterizing mangrove soils under different type of vegetation (Rhizophora/Avicennia/dead mangrove) in the Venezuelan coast. The soils were anoxic, with a pH~7; however other soil parameters varied widely (e.g., clay, organic carbon). Dead mangrove area showed a significant lower amounts of total organic carbon (TOC) (6.8±2.2%), in comparison to the well-preserved mangrove of Avicennia or Rhizophora (TOC=17-20%). Our results indicate that 56% of the TOC was lost within a period of 10years and we estimate that 11,219kgm -2 of CO 2 was emitted as a result of the mangrove death. These results represent an average emission rate of 11.2±19.17tCO 2 ha -1 y -1 ., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Geogenic arsenic (As) can accumulate and reach high concentrations in rice grains, thus representing a potential threat to human health. Ecuador is one of the main consumers of rice in South America. However, there is no information available about the concentrations of As in rice agrosystems, although some water bodies are known to contain high levels of the element. We carried out extensive sampling of water, soil, rice plants and commercial rice (obtained from local markets). Water samples were analysed to determine physico-chemical properties and concentrations of dissolved arsenic. Soil samples were analysed to determine total organic C, texture, total Fe and amorphous Fe oxyhydroxides (Fe Ox ), total arsenic (tAs) and the bioavailable fraction (As Me ). The different plant parts were analysed separately to determine total (tAs), inorganic (iAs) and organic arsenic (oAs). Low concentrations of arsenic were found in samples of water (generally <10μgl -1 ) and soil (4.48±3mgkg -1 ). The tAs in the rice grains was within the usual range (0.042-0.125mgkg -1 dry weight, d.w.) and was significantly lower than in leaves (0.123-0.286mgkg -1 d.w.) and stems (0.091-0.201mgkg -1 d.w.). The Fe Ox and tAs and also As Me in flood water were negatively correlated with tAs in the plants. However, the concentrations of As in stems and leaves were linearly correlated with tAs in the soil and flood water. The relationship between tAs and arsenic in the grain fitted a logarithmic function, as did that between tAs in the grain and the stem. The findings seem to indicate that high concentrations of arsenic in the environment (soil or water) or in the rice stem do not necessarily imply accumulation of the element in the grain. The iAs form was dominant (>80%) in all parts of the rice plants., (Copyright © 2016 Elsevier B.V. All rights reserved.)

During the period 1980-2000, the yellow-legged gull population underwent exponential growth due to an increase in the availability of anthropogenic food resources. The aim of this study was to highlight the effect of the gull colonies on the P soil cycle and the associated effects on coastal ecosystems. Samples of soil, water and faecal material were collected in a colony of yellow-legged gulls (Cíes Islands) and in a control area. Four sampling plots were installed in the study areas, and samples were collected in summer and winter in 1997 and 2011. Sample analysis included soil characterization and determination of the total P content (TP), bioavailable-P and fractionated-P forms in the soils and faecal material. The (31)P NMR technique was also used to determine organic P forms. Clear differences between the gull colony soils and the control soil were observed. The TP was 3 times higher in the gull colony soil, and the bioavailable P was 30 times higher than in the control soil. The P forms present at highest concentrations in the faecal material (P-apatite, P-residual and P-humic acid) were also present at high concentrations in the colony soil. The absence of any seasonal or annual differences in P concentration indicates that the P has remained stable in the soil over time, regardless of the changes in the gull population density. The degree of P saturation indicated that soils are saturated with P due to the low concentration of Fe/Al-hydroxides, which is consistent with a high P concentration in the run-off from the colonies. The P output from the colony soils to coastal waters may cause eutrophication of a nearby lagoon and the disappearance of a Zostera marina seagrass meadow. Similarly, the enrichment of P concentration in dune system of Muxieiro may induce irreversible changes in the plant communities., (Copyright © 2015 Elsevier B.V. All rights reserved.)