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2.
Environ Manage ; 73(4): 753-768, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38063877

RESUMEN

Land cover change scenarios hold far-reaching implications for ecosystem services (ES), highlighting the need for understanding the trade-offs and synergies underlying the provision of multiple ES. The insufficient knowledge of the mechanisms governing the relationships among multiple ES, along with the lack of information on trade-offs among ES under different scenarios, restricts the ability to provide effective information for decision-makers. To fill this gap, we assessed the interplay among six ES: climate regulation, habitat creating and maintaining species diversity, cultivated crops, regulation of the chemical condition of freshwaters by living processes (water quality), water yield, and control of erosion rates, within three river basins in northwest Portugal. We employed the InVEST to map the state of these ES in 2018, along with three projected land cover scenarios for 2050: business-as-usual, farmland return, and afforestation. Our findings indicated the business-as-usual scenario could lead to detrimental impacts on climate regulation, habitat creating and maintaining species diversity, and control of erosion rates. In contrast, the farmland return scenario showed less drastic decreases in habitat-creating and maintaining species diversity and control of erosion rates compared to the business-as-usual scenario. Afforestation emerged as the most favorable scenario, with a 13.6% increase in climate regulation and a 1.3% improvement in habitat-creating and maintaining species diversity. Cluster analysis allowed the identification of six levels of spatial synergies between ES, with regions of high forest cover showing extreme synergy and populated areas exhibiting the lowest levels of synergy, suggesting that a well-planned combination of these practices could yield substantial benefits for future ES provision. These results provide crucial insights for decision-makers to enhance ecosystem management and promote societal well-being. Importantly, our findings underscore the significance of considering multiple ES and their interrelationships in land use planning to achieve sustainable development objectives.


Asunto(s)
Ecosistema , Ríos , Conservación de los Recursos Naturales/métodos , Bosques , Desarrollo Sostenible , China
3.
Environ Res ; 216(Pt 1): 114473, 2023 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-36195158

RESUMEN

Persistent organic pollutants (POPs) were analyzed in 136 blubber samples of Franciscana dolphins from Brazil (Pontoporia blainvillei), which is the most threatened dolphin in the Southwestern Atlantic. The dolphins were caught by the fishery fleet and collected from 2000 to 2018 in three regions of São Paulo state: northern São Paulo (SPN), central São Paulo (SPC), and southern São Paulo (SPS). The POPs analyzed in this study were polychlorinated biphenyls (PCBs), dichlorodiphenyltrichloroethane (DDTs), Mirex, hexachlorobenzene (HCB), chlordane compounds (CHLs), hexachlorocyclohexane isomers (HCHs), and polybrominated diphenyl ethers (PBDEs). The concentrations ranged from 36 to 7200 ng g-1 lipid weight (lw) and 113-42200 ng g-1 lw for predominant compounds DDTs and PCBs, respectively. Similar profiles of PCB congeners were observed with a predominance of hexachlorinated compounds, representing approximately 50% of the total PCB amount; the highest PCB concentrations were observed from Baixada Santista (SPC) proximate to a highly urbanized and industrial coastal area. Significant differences were observed between the sexes and maturity of dolphins, mainly for PCBs, DDTs, and Mirex. In general, POPs other than HCB in Franciscana dolphins showed downward temporal trends, matching the regulatory periods for restricting and/or banning these compounds. Although POP concentrations are declining, PCB levels remain high in small dolphins, suggesting adverse health effects on Franciscanas. As organic contaminants are one of the numerous threats Franciscanas have been vulnerable to along the Brazilian coast, we recommend monitoring POPs levels every five years to check for declining (or stabilizing) trends.


Asunto(s)
Delfines , Contaminantes Ambientales , Bifenilos Policlorados , Contaminantes Químicos del Agua , Animales , Bifenilos Policlorados/análisis , Hexaclorobenceno , Contaminantes Orgánicos Persistentes , Mírex , Monitoreo del Ambiente , Contaminantes Químicos del Agua/análisis , Brasil , Éteres Difenilos Halogenados/análisis , DDT
4.
Environ Res ; 214(Pt 4): 114157, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36027956

RESUMEN

In this study, we investigated factors that influence the differences in exposure of perfluoroalkyl acids (PFAAs) from eight species of Antarctic seabirds, including Pygoscelis penguins, Stercorarius maccormicki, and Macronectes giganteus. We analyzed the relationship between foraging ecology (based on δ13C, δ15N, and δ34S values) and PFAAs accumulated in eggs and breast feathers. Ten out of 15 targeted PFAAs were detected in eggs compared to eight in feathers. Mean ∑PFAA concentrations in feathers ranged from 0.47 in P. antarcticus to 17.4 ng/g dry weight (dw) in S. maccormicki. In eggs, ∑PFAA concentrations ranged from 3.51 in P. adeliae to 117 ng/g dw in S. maccormicki. The highest concentrations of most PFAAs were found in trans-equatorial migrators such as S. maccormicki, probably due their high trophic position and higher concentrations of PFAAs in the Northern Hemisphere compared to the Southern Hemisphere. Based on stable isotopes correlations, our results suggest that the trophic position (δ15N) and the foraging area (δ13C and δ34S) influence PFAAs concentrations in Antarctic seabirds. Our results point to the possibility that long-distance migratory birds may have as bio-vectors in the transport of pollutants, including PFCAs, in Antarctic environments, although this must be further confirmed in future studies using a mass balanced approach, such as extractable organofluorine (EOF).


Asunto(s)
Contaminantes Ambientales , Fluorocarburos , Spheniscidae , Animales , Regiones Antárticas , Monitoreo del Ambiente/métodos , Plumas/química , Fluorocarburos/análisis
5.
Environ Res ; 206: 112421, 2022 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-34838759

RESUMEN

Trace metals bioaccumulate in aquatic organisms and some of them biomagnify through food webs, posing a threat to the organisms or their human consumers. Although the trophodynamics of many trace metals is well known in the northern hemisphere, much less is known about metals in aquatic food webs from cold and remote coastal zones of the southern hemisphere. To fill this gap, we investigated the trophodynamics of Al, Co, Cr, Li, Mo, Ni, Sr, and V, which were measured in marine macroinvertebrates and fishes from inshore and offshore locations in each of the Chilean Patagonia and the Antarctic Peninsula area. In Patagonia, there was biodilution of these metals across the whole food web, while biomagnification of Li and Ni was significantly found across the lower food web at the offshore site. In Antarctica, significant biodilution of Al, Li, Ni, Mo, Sr and V occurred through the whole food web for the inshore site, but no tendency (biodilution or biomagnification) was found (p > 0.05) across the organisms at lower trophic levels for the offshore site. Our data suggest that the geographic location and species influences the trophodynamics of these trace elements and expand our understanding of metal fate in remote locations of the southern hemisphere.


Asunto(s)
Oligoelementos , Contaminantes Químicos del Agua , Animales , Organismos Acuáticos , Monitoreo del Ambiente , Peces , Cadena Alimentaria , Oligoelementos/análisis , Contaminantes Químicos del Agua/análisis
6.
Sci Total Environ ; 770: 145259, 2021 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-33517007

RESUMEN

Long-finned pilot whales (LFPW) are cetaceans with strong social groups often involved in mass strandings worldwide. However, these beachings occur for reasons that are not fully understood. In 2016, 124 LFPW were stranded on the Chilean Patagonian islands, offering a unique opportunity to obtain crucial information on the ecology, biology, and genetics of this population. In addition, we examined whether persistent organic pollutants (POPs) and trace elements (TEs) were responsible for this mass mortality. Stable isotopes (δ13C & δ15N) and genetic analyses were used to reconstruct the trophic ecology, social structure, and kinship of LFPW and compared to POPs and TEs levels found in LFPW. Mitochondrial DNA analyses on 71 individuals identified four maternal lineages within the stranded LFPW. Of these animals, 32 individuals were analyzed for a suite of POPs, TEs, and lipid content in blubber. The highest levels were found for ΣDDXs (6 isomers) (542.46 ± 433.46 ng/g, lw) and for total Hg (2.79 ± 1.91 mg/kg, dw). However, concentrations found in these LFPW were lower than toxicity thresholds and those reported for LFPW stranded in other regions. Evidence was found of ΣDDX, Σ7PCBs, and Cd bioaccumulation and maternal transfer of POPs in mother/offspring groups. Nevertheless, no clear relationship between contaminant concentrations and LFPW mortality was established. Further research is still needed to assess LFPW populations including conservations status and exposure to chemicals in remote areas such as Patagonia.


Asunto(s)
Contaminantes Ambientales , Ballena de Aleta , Contaminantes Químicos del Agua , Calderón , Animales , Bioacumulación , Chile , Monitoreo del Ambiente , Contaminantes Químicos del Agua/análisis
7.
Biol Trace Elem Res ; 197(1): 285-293, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31828723

RESUMEN

Patagonia and Antarctica are biodiverse regions in the Southern Hemisphere, but little is known about the levels of trace elements in marine organisms from these remote coastal ecosystems. In this study, selenium (Se), copper (Cu), zinc (Zn), and stable isotopes of nitrogen (δ15N; relative trophic level) were measured in 36 marine species collected from two locations of the Chilean Patagonia and two locations of the Antarctic Peninsula area to determine whether biomagnification of these trace elements occurs in the food webs. Results indicated that Cu, Se, and Zn levels were slightly lower than those in similar species from elsewhere, and the highest metal levels were found in marine macroinvertebrates compared with fishes. There was evidence of Cu, Se, and Zn biomagnification but only within the lower-trophic-level organisms. When assessing whole food webs, levels of these elements typically decreased from macroinvertebrates to fishes or birds, suggesting lower risks of metal toxicity to higher-level consumers.


Asunto(s)
Selenio , Contaminantes Químicos del Agua , Animales , Regiones Antárticas , Cobre , Ecosistema , Monitoreo del Ambiente , Peces , Cadena Alimentaria , Contaminantes Químicos del Agua/análisis , Zinc
8.
Mar Pollut Bull ; 151: 110822, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31868594

RESUMEN

The use of trace metals and rare-earth elements (REEs) is increasing in the mining, metallurgic, electronic, and automobile industries due to their magnetic, heat-resistant, and phosphorescent properties. While large amounts of these metals are released to the environment, the toxic consequences in marine organisms are poorly understood. In Chile a mass stranding event of long-finned pilot whales (LFPW) (Globicephala melas) occurred in 2016 due to unknown consequences. Al, Ce, Cr, Cu, Tl, and Zn concentrations were analyzed in LFPW blubber tissue and correlated with body size and age class of individuals. While Al and Zn were higher in juvenile individuals, Ce, Cu, Cr, and Tl were higher in adults. This study provides the first base line of trace metals and REE in LFPW from the southern hemisphere and demonstrates the existence and persistence of trace elements in marine top predators from remote ecosystems like the Chilean Patagonia.


Asunto(s)
Oligoelementos/análisis , Calderón , Animales , Chile
9.
Mar Pollut Bull ; 140: 60-64, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30803682

RESUMEN

Environmental concentrations of Pb have been increased due to anthropogenic activities, which have provoked the released of this element to the environment in large amounts. To understand how Pb behaves in remote southern marine ecosystems, we measured Pb concentrations and isotope ratios in biota from coastal marine ecosystems of the Chilean Patagonia and the Antarctic Peninsula area. Lead concentrations in the aquatic organisms ranged from 0.02 to 1.19 mg kg-1 d.w. In Patagonia, higher Pb levels were found in fish than in invertebrates (crab, shrimp, porifera, limpet and shellfish). In comparison with the baseline reference values from other parts of the world, fishes exhibited lower Pb levels. The results of Pb isotopic compositions indicated that the bioaccumulation of Pb in marine organisms come from different anthropogenic sources. These Pb levels might be useful for further studies that allow a deeper evaluation of sources for Pb contamination in these remote ecosystems.


Asunto(s)
Peces , Invertebrados/química , Plomo/análisis , Contaminantes Químicos del Agua/análisis , Animales , Regiones Antárticas , Organismos Acuáticos , Braquiuros/química , Chile , Monitoreo del Ambiente , Isótopos/análisis , Plomo/farmacocinética , Poríferos/química , Contaminantes Químicos del Agua/farmacocinética
10.
Mar Pollut Bull ; 137: 246-251, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30503432

RESUMEN

In aquatic environments, Cd contamination is a great concern because this non-essential metal presents risks both for wildlife and human health. Data about the concentration and transfer of Cd in Patagonian and Antarctic aquatic food webs are crucial for assessing the impacts of this element in pristine ecosystems. Consequently, the concentration of Cd was measured in thirty-two species collected in the 2014 austral summer from two locations of the Western Patagonia and two locations of the Antarctic Peninsula. The main objective of this work was to assess the relationship between Cd concentration and trophic level determined by δ15N. In the studied trophic positions, Cd showed a positive relationship between concentration and trophic level, which suggests biomagnification of this element in macroinvertebrates. However, there was a significant dilution when higher trophic organisms were considered.


Asunto(s)
Cadmio/análisis , Cadena Alimentaria , Contaminantes Químicos del Agua/análisis , Regiones Antárticas , Chile , Ecosistema
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