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1.
Sci Total Environ ; 926: 171699, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38508250

RESUMO

Floodbank realignment is a common practice aimed at restoring salt marsh vegetation on previously embanked land. However, experiences indicate that it may take several years before salt marsh vegetation becomes fully established. Various challenges arising from ecogeomorphic feedback mechanisms could pose significant setbacks to vegetation recolonization. The widespread adoption of transplantation techniques for the restoration and rehabilitation of rewilded landscapes has indeed proven to be a valuable tool for accelerating plant development. In the Ria Formosa coastal lagoon (South of Portugal), a pilot plan was implemented, and two salt marsh pioneer species, Spartina maritima (syn. Sporobolus maritimus) and Sarcocornia perennis (syn. Salicornia perennis), were transplanted from a natural salt marsh to a rewilded marsh. Biodegradable 3D porous structures were installed to mimic transplant clumping, aid sedimentation, and enhance the plant's initial adjustment. Ecological, sediment, and hydrodynamic data were collected during the 12-month pilot restoration plan. The environmental profiles of the donor and restoration sites were compared to substantiate the success of the transplants in the rewilded salt marsh. Results show that although plant shoot density decreased after the transplanting, Spartina maritima acclimated well to the new environmental conditions of the restoration site, showing signs of growth and cover increase, whilst Sarcocornia perennis was not able to acclimatize and survive in the restoration site. The failure behind the Sarcocornia perennis acclimation might be related to the bed properties and topographic properties of the restoration site in the rewilded marsh. Major findings contribute to a more comprehensive understanding of how salt marsh pioneering vegetation successfully colonizes disturbed habitats, facilitated using 3D-biodegradable structures.


Assuntos
Chenopodiaceae , Áreas Alagadas , Sedimentos Geológicos/química , Ecossistema , Poaceae
2.
Mar Pollut Bull ; 197: 115762, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37979526

RESUMO

Seagrass meadows provide several ecological functions that improve the overall ecological health of coastal systems and therefore, it is urgent to promote the restoration of such habitats. In Ria de Aveiro, a coastal lagoon in the Atlantic Coast of Portugal, a restoration initiative was responsible for transplanting the dwarf eelgrass Zostera noltei into a highly degraded area. This eelgrass was used as a nature-based solution (NbS) to mitigate some of the impacts of historical mercury contamination. Comparisons of key-species features (density and biomass), and some community-derived indicators (total density and biomass, species richness and Shannon-Wiener index) between the transplanted seagrass patch, their bare vicinities, and their counterpart habitats on the source area, provided signs of the effectiveness of the restoration action on the benthic communities' recovery. Indicators were higher within the restored meadow, and biomass derived indicators of the restored meadow were similar to the source meadow.


Assuntos
Mercúrio , Zosteraceae , Ecossistema , Biomassa , Portugal
3.
Front Plant Sci ; 14: 1088643, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37021321

RESUMO

In the last three decades, quantitative approaches that rely on organism traits instead of taxonomy have advanced different fields of ecological research through establishing the mechanistic links between environmental drivers, functional traits, and ecosystem functions. A research subfield where trait-based approaches have been frequently used but poorly synthesized is the ecology of seagrasses; marine angiosperms that colonized the ocean 100M YA and today make up productive yet threatened coastal ecosystems globally. Here, we compiled a comprehensive trait-based response-effect framework (TBF) which builds on previous concepts and ideas, including the use of traits for the study of community assembly processes, from dispersal and response to abiotic and biotic factors, to ecosystem function and service provision. We then apply this framework to the global seagrass literature, using a systematic review to identify the strengths, gaps, and opportunities of the field. Seagrass trait research has mostly focused on the effect of environmental drivers on traits, i.e., "environmental filtering" (72%), whereas links between traits and functions are less common (26.9%). Despite the richness of trait-based data available, concepts related to TBFs are rare in the seagrass literature (15% of studies), including the relative importance of neutral and niche assembly processes, or the influence of trait dominance or complementarity in ecosystem function provision. These knowledge gaps indicate ample potential for further research, highlighting the need to understand the links between the unique traits of seagrasses and the ecosystem services they provide.

4.
Curr Biol ; 32(7): 1641-1649.e3, 2022 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-35196506

RESUMO

There is an urgent need to halt and reverse loss of mangroves and seagrass to protect and increase the ecosystem services they provide to coastal communities, such as enhancing coastal resilience and contributing to climate stability.1,2 Ambitious targets for their recovery can inspire public and private investment in conservation,3 but the expected outcomes of different protection and restoration strategies are unclear. We estimated potential recovery of mangroves and seagrass through gains in ecosystem extent to the year 2070 under a range of protection and restoration strategies implemented until the year 2050. Under a protection-only scenario, the current trajectories of net mangrove loss slowed, and a minor net gain in global seagrass extent (∼1%) was estimated. Protection alone is therefore unlikely to drive sufficient recovery. However, if action is taken to both protect and restore, net gains of up to 5% and 35% of mangroves and seagrasses, respectively, could be achieved by 2050. Further, protection and restoration can be complementary, as protection prevents losses that would otherwise occur post-2050, highlighting the importance of implementing protection measures. Our findings provide the scientific evidence required for setting strategic and ambitious targets to inspire significant global investment and effort in mangrove and seagrass conservation.


Assuntos
Ecossistema , Áreas Alagadas , Clima , Conservação dos Recursos Naturais
5.
J Environ Manage ; 302(Pt A): 113969, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34715611

RESUMO

Seagrass meadows provide important and valuable ecosystem services. They are affected by several natural and human-induced stressors, but a combination of natural recovery and management actions have recently inverted the worldwide reduction. The main objectives of this study were to provide science-based knowledge on ecology and restoration, framed on environmental-related policies. By coupling the general guidelines with practical experience, obtained from sequential in situ experiments carried out for several months in a show-case study area, this study provides guidelines useful for restoration practitioners. A decision-making approach is proposed to answer the following questions: 1) What is the best Zostera noltei transplanting method? 2) What is the best technique to reduce the bioturbation activity of Arenicola spp.?, 3) Do bioturbation reduction techniques affect the survival rate of Z. noltei transplants?, and finally, 4) What are the key steps to maximize the success of a Z. noltei transplant and increase the species' resilience? Having a Portuguese coastal lagoon as show-case (Mira Channel, Ria de Aveiro), different transplant and restoration methodologies were tested (i.e. metal frames, nails, bamboo sticks, shoots inserted unanchored into the sediment, and intact units of sediment with seagrasses, named as SODs) to assure low environmental impact on donor meadows, high survival rate of transplanted shoots and the recovery of fragmented or lost meadows. Moreover, to potentially reverse a degraded Arenicola spp. colonized seagrass habitat, different types of natural membranes were tested. Results showed that the best transplanting method is the use of SODs as the self-facilitation process of Z. noltei is enhanced, while being the least invasive for the donor population. The use of a natural membrane can significantly decrease the bioturbation stress caused by Arenicola spp., with jute membrane being the best option, given its cost-handling-benefit trade-offs. Enhancing the success of seagrass restoration requires the implementation of effective measures by environmental restoration practitioners. We defined a three-step process to improve the resilience of Z. noltei. This stepwise approach consists on 1) Characterization of the donor population, 2) Identification of the constraints and implementation of measures to prevent them, and 3) Scale-up the restoration plan. The application of this stepwise approach in intertidal coastal and estuarine systems management will, therefore, facilitate the success of Z. noltei restoration plans.


Assuntos
Recuperação e Remediação Ambiental , Zosteraceae , Ecossistema , Humanos
6.
J Ophthalmol ; 2020: 8067657, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32318285

RESUMO

Bifocal and multifocal optical devices are intended to get images into focus from objects placed at different distances from the observer. Spectacles, contact lenses, and intraocular lenses can meet the requirements to provide such a solution. Contact lenses provide unique characteristics as a platform for implementing bifocality and multifocality. Compared to spectacles, they are closer to the eye, providing a wider field of view, less distortion, and their use is more consistent as they are not so easily removed along the day. In addition, contact lenses are also minimally invasive, can be easily exchangeable, and, therefore, suitable for conditions in which surgical procedures are not indicated. Contact lenses can remain centered with the eye despite eye movements, providing the possibility for simultaneous imaging from different object distances. The main current indications for bifocal and multifocal contact lenses include presbyopia correction in adult population and myopia control in children. Considering the large numbers of potential candidates for optical correction of presbyopia and the demographic trends in myopia, the potential impact of contact lenses for presbyopia and myopia applications is undoubtedly tremendous. However, the ocular characteristics and expectations vary significantly between young and older candidates and impose different challenges in fitting bifocal and multifocal contact lenses for the correction of presbyopia and myopia control. This review presents the recent developments in material platforms, optical designs, simulated visual performance, and the clinical performance assessment of bifocal and multifocal contact lenses for presbyopia correction and/or myopia progression control.

7.
Sci Rep ; 9(1): 14387, 2019 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-31591415

RESUMO

This work assessed the Blue Carbon (C) stock in the seagrass meadows (Zostera noltei) of Ria de Aveiro coastal lagoon (Portugal), and evaluated its spatio-temporal trend over the 2003-2005 to 2013-2014 period. Zostera noltei spatial distribution, restricted to intertidal areas in 2014, was mapped by remote sensing using an unmanned aerial vehicle (UAV) and aerial photography. Zostera noltei biomass was also monitored in situ over a year and its Blue C stock was estimated. By 2014, intertidal meadows covered an area of 226 ± 4 ha and their Blue C stock ranged from 227 ± 6 to 453 ± 13 Mg C. Overall, Ria de Aveiro Z. noltei intertidal meadows increased in extent over the 2003-2005 to 2013-2014 period, corroborating the recent declining trend reversal observed in Europe and contrary to the global decline trend. This spatio-temporal shift might be related to a natural adjustment of the intertidal meadows to past human intervention in Ria de Aveiro, namely large-scale dredging activities, particularly in the 1996-1998 period, combined with the more accurate assessment performed in 2014 using the UAV. This recovery contributes to the effective increase of the Blue C stock in Ria de Aveiro and, ultimately, to supporting climate regulation and improving ecosystem health. However, major dredging activities are foreseen in the system's management plan, which can again endanger the recovery trend of Z. noltei intertidal meadows in Ria de Aveiro.

8.
Food Chem ; 283: 596-603, 2019 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-30722917

RESUMO

The spice made from the fruits of Piper nigrum L. (Piperaceae) has high economic value since the beginnings of international trade. Because its price has been increasing, adulterations with papaya seeds, cayenne pepper and maize flour were reported. These have been screened by methodologies dedicated to the detection of single adulterants lacking sensitivity and specificity. Herein we propose a specific, highly-sensitive, high-throughput and affordable qPCR-based methodology for the detection of P. nigrum contaminants (Carica papaya, Zea mays and Capsicum annuum) using plant DNA barcodes trnL and psbA-trnH. The method enables the specific detection of contaminants in a short time with low limits of detection (LOD6 values of 1, 2 and 10 Haploid Genome Equivalents). A market survey (29 samples) revealed 41% of samples contaminated, though about ¾ at very low levels indicating accidental contamination. The proposed tool will contribute to the improvement of quality of this much traded spice.


Assuntos
Código de Barras de DNA Taxonômico/métodos , DNA de Plantas/análise , Piper nigrum/genética , Capsicum/genética , Carica/genética , Primers do DNA/metabolismo , DNA de Plantas/genética , DNA de Plantas/metabolismo , Frutas/genética , Limite de Detecção , Hibridização de Ácido Nucleico , Proteínas de Plantas/genética , Reação em Cadeia da Polimerase em Tempo Real , Zea mays/genética
9.
Sci Total Environ ; 652: 1113-1128, 2019 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-30586798

RESUMO

The Baixo Vouga Lagunar (BVL) is part of Ria de Aveiro coastal lagoon in Portugal, which is classified as a Special Protection Area under the European Habitats and Birds Directives. This part of the system, corresponding to the confluence of the Vouga River with the lagoon, is very important culturally and socioeconomically for the local communities, taking place several human activities, especially agriculture. To prevent salt water intrusion from the Ria de Aveiro into agriculture fields, a floodbank was initiated in the 90's. In frame of ongoing changes in Ria de Aveiro hydrodynamics, the existing floodbank will be now extended, introducing further changes in the ecological dynamics of the BVL and its adjacent area. As a consequence, the water level in the floodbank downstream side is expected to rise, increasing the submersion period in tidal wetlands, and leading to coastal squeeze. The aim of this study is to apply an ecosystem based-management approach to mitigate the impacts on biodiversity resulting from the management plan. To do so, we have modelled the implications of the changes in several hydrological and environmental variables on four saltmarsh species and habitats distribution, as well as on their associated ecosystem services, both upstream and downstream of the floodbank. The ecosystem services of interest were prioritized by stakeholders' elicitation, which were then used as an input to a spatial multi-criteria analysis aimed to find the best management actions to compensate for the unintended loss of biodiversity and ecosystem services in the BVL. According to our results, the main areas to be preserved in the BVL were the traditional agricultural mosaic fields; the freshwater courses and the subtidal estuarine channels. By combining ecology with the analysis of social preferences, this study shows how co-developed solutions can support adaptive management and the conservation of coastal ecosystems.

10.
Sci Rep ; 7(1): 1336, 2017 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-28465595

RESUMO

The present study aims to assess the plastic response of Zostera noltei meadows traits under spatio-temporal shifts in salinity combined with sediment environmental variables (temperature; pH; loss-on-ignition (LOI); carbon (C) and nitrogen (N) pools (top 5 cm)). Z. noltei biomass, C and N pools, leaf photosynthetic performance and esterified fatty acid (FA) profile were assessed within a temperate coastal lagoon during winter and late spring, along sites spatially distributed. None of the surveyed traits for Z. noltei displayed a clear spatial trend. Z. noltei proved to be euryhaline, whose biology was only slightly affected within this salinity range, in each season (14-39 in winter; 33-41 in late spring). Seasonal differences in salinity and environmental parameters explain the differences recorded in Z. noltei traits (aboveground biomass, N and C pools; photosynthetic performance). Spatio-temporal salinity shifts did not significantly affect the pool of FA present in Z. noltei. Overall, within the salinity range surveyed, the ecological processes studied and regulating Z. noltei meadows do not appear to be at risk. This work reinforces the plasticity of Z. noltei to salinity shifts within the studied range, with this finding being particularly relevant in the context of extreme weather events (e.g., winter freshwater floods, summer droughts).


Assuntos
Ecossistema , Pradaria , Salinidade , Zosteraceae/fisiologia , Biomassa , Carbono/metabolismo , Ácidos Graxos/análise , Sedimentos Geológicos , Nitrogênio/metabolismo , Fotossíntese , Estações do Ano
11.
Sci Rep ; 7: 41225, 2017 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-28120885

RESUMO

Ria de Aveiro is a mesotidal coastal lagoon with one of the largest continuous salt marshes in Europe. The objective of this work was to assess C, N and P stocks of Spartina maritima (low marsh pioneer halophyte) and Juncus maritimus (representative of mid-high marsh halophytes) combined with the contribution of Halimione portulacoides, Sarcocornia perennis, and Bolbochenous maritimus to the lagoon ≈4400 ha marsh area. A multivariate analysis (PCO), taking into account environmental variables and the annual biomass and nutrient dynamics, showed that there are no clear seasonal or spatial differences within low or mid-high marshes, but clearly separates J. maritimus and S. maritima marshes. Calculations of C, N and P stocks in the biomass of the five most representative halophytes plus the respective rhizosediment (25 cm depth), and taking into account their relative coverage, represents 252053 Mg C, 38100 Mg N and 7563 Mg P. Over 90% of the stocks are found within mid-high marshes. This work shows the importance of this lagoon's salt marshes on climate and nutrients regulation, and defines the current condition concerning the 'blue carbon' and nutrient stocks, as a basis for prospective future scenarios of salt marsh degradation or loss, namely under SLR context.


Assuntos
Carbono/metabolismo , Magnoliopsida/metabolismo , Plantas Tolerantes a Sal/metabolismo , Áreas Alagadas , Biomassa , Magnoliopsida/crescimento & desenvolvimento , Nitrogênio/metabolismo , Fósforo/metabolismo , Portugal , Plantas Tolerantes a Sal/crescimento & desenvolvimento , Estações do Ano
12.
Integr Environ Assess Manag ; 12(4): 726-34, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27064511

RESUMO

This article shares the experiences, observations, and discussions that occurred during the completing of an ecosystem services (ES) indicator framework to be used at European Union (EU) and Member States' level. The experience base was drawn from 3 European research projects and 14 associated case study sites that include 13 transitional-water bodies (specifically 8 coastal lagoons, 4 riverine estuaries, and 1 fjord) and 1 coastal-water ecosystem. The ES pertinent to each case study site were identified along with indicators of these ES and data sources that could be used for mapping. During the process, several questions and uncertainties arose, followed by discussion, leading to these main lessons learned: 1) ES identification: Some ES that do not seem important at the European scale emerge as relevant at regional or local scales; 2) ES indicators: When direct indicators are not available, proxies for indicators (indirect indicators) might be used, including combined data on monitoring requirements imposed by EU legislation and international agreements; 3) ES mapping: Boundaries and appropriate data spatial resolution must be established because ES can be mapped at different temporal and spatial scales. We also acknowledge that mapping and assessment of ES supports the dialogue between human well-being and ecological status. From an evidence-based marine planning-process point of view, mapping and assessment of marine ES are of paramount importance to sustainable use of marine natural capital and to halt the loss of marine biodiversity. Integr Environ Assess Manag 2016;12:726-734. © 2016 SETAC.


Assuntos
Conservação dos Recursos Naturais/métodos , Ecossistema , Monitoramento Ambiental/métodos , Estuários , Biodiversidade , Política Ambiental , União Europeia
13.
Sci Rep ; 6: 22782, 2016 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-26964892

RESUMO

A variety of ecosystem services classification systems and mapping approaches are available in the scientific and technical literature, which needs to be selected and adapted when applied to complex territories (e.g. in the interface between water and land, estuary and sea). This paper provides a framework for addressing ecosystem services in complex coastal regions. The roadmap comprises the definition of the exact geographic boundaries of the study area; the use of CICES (Common International Classification of Ecosystem Services) for ecosystem services identification and classification; and the definition of qualitative indicators that will serve as basis to map the ecosystem services. Due to its complexity, the Ria de Aveiro coastal region was selected as case study, presenting an opportunity to explore the application of such approaches at a regional scale. The main challenges of implementing the proposed roadmap, together with its advantages are discussed in this research. The results highlight the importance of considering both the connectivity of natural systems and the complexity of the governance framework; the flexibility and robustness, but also the challenges when applying CICES at regional scale; and the challenges regarding ecosystem services mapping.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Mapeamento Geográfico , Portugal , Análise Espacial
14.
Mar Pollut Bull ; 62(7): 1584-7, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21592533

RESUMO

Due to increasing global population, salt marshes have been subjected to multiple stressors such as increasing nutrient loadings and historical contamination. In order to better understand how does the salt marsh plants auto-remediation capacity (phytoaccumulation of metals) is affected by cultural eutrophication, an experiment was performed under controlled conditions. Plants were exposure to equal metal concentrations (Zn, Cu, and Ni - micronutrients, and Cd - class B metal) simulating historical contamination and three different concentrations of nitrogen (nitrate) simulating steps of cultural eutrophication. According to our study, under the tested concentrations, cultural eutrophication does not seem to affect Zn, Cu and Ni phytoremediation of H. portulacoides, but the ecosystem service of Cd phytoremediation seems to be promoted. Nevertheless, Cd high toxicity and bioaccumulation should be taken into account, as well as the vulnerability of salt marsh ecosystems, whose reduction will have drastic consequences to the ecosystem health.


Assuntos
Plantas/metabolismo , Poluentes Químicos da Água/metabolismo , Áreas Alagadas , Biodegradação Ambiental , Ecossistema , Monitoramento Ambiental , Metais/análise , Metais/metabolismo , Desenvolvimento Vegetal , Estresse Fisiológico , Poluentes Químicos da Água/análise
15.
Mar Pollut Bull ; 61(4-6): 215-23, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20304438

RESUMO

Salt marshes constitute highly productive systems playing an important role on ecosystem functions. The aim of this study is to compare the role of Spartina maritima salt marshes on carbon cycling. Thus, four salt marshes located in two mesotidal estuarine systems (Tagus and Mondego, two salt marshes per estuary) were studied. The S. maritima above- and belowground biomass, carbon production, decomposition rates (through a litterbag experiment) and carbon content in the sediment were estimated for a one year period in both systems and compared. In Corroios (located at the Tagus estuary) S. maritima salt marsh had the highest belowground production (1008 gC m(-2) y(-1)), slower decomposition rate (k=0.0024 d(-1)), and the highest carbon content in sediments (750 gC m(-2) y(-1)); and thus, the highest carbon retention capacity. The other three salt marshes had comparatively higher aboveground productions, higher decomposition rates and lower carbon retention capacity. Therefore, Corroios had the most important carbon cycling characteristics. As a whole, results show that differences in carbon cycling in salt marshes depend mostly on its own characteristics and maturity, rather than the system itself. The intrinsic characteristics of the salt marshes, namely the physicochemical conditions determined by the maturity of the system, are more important factors affecting the role of warm-temperate mesotidal salt marshes as carbon sinks.


Assuntos
Carbono/metabolismo , Poaceae/fisiologia , Clima Tropical , Áreas Alagadas , Biomassa , Geografia , Sedimentos Geológicos , Oceanos e Mares , Poaceae/crescimento & desenvolvimento , Portugal , Rios
16.
Adapt Phys Activ Q ; 26(3): 236-58, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19799096

RESUMO

This study reports on a comparison of how two different groups of people with an amputation view their bodies and perceive how others view them. One group has a history of sport participation, while the other has not. The analysis is based on 14 semistructured interviews with people with amputations: 7 were engaged in sport and 7 were not. The following themes emerged: Body, Prosthesis, Independence, Huma Person, and Social Barriers. One could conclude that participation in sport influences how people with an amputation perceive their body as they live with their body in a more positive way and they better accept their new body condition and their being-in-the-world. The social barriers that people with an amputation have to face daily were evident, and one of the most significant ideas was the importance of being recognized and treated as a person and not as a person with a disability.


Assuntos
Adaptação Psicológica , Amputação Cirúrgica/psicologia , Imagem Corporal , Pessoas com Deficiência/psicologia , Preconceito , Percepção Social , Adulto , Amputação Cirúrgica/estatística & dados numéricos , Membros Artificiais/psicologia , Feminino , Humanos , Masculino , Modelos Psicológicos , Atividade Motora , Autonomia Pessoal , Estresse Psicológico/etiologia , Estresse Psicológico/psicologia , Inquéritos e Questionários
17.
Environ Pollut ; 156(3): 628-35, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18684544

RESUMO

Salt marshes are among the most productive ecosystems in the world, performing important ecosystem functions, particularly nutrient recycling. In this study, a comparison is made between Mondego and Tagus estuaries in relation to the role of Spartina maritima in nitrogen retention capacity and cycling. Two mono-specific S. maritima stands per estuary were studied during 1yr (biomass, nitrogen (N) pools, litter production, decomposition rates). Results showed that the oldest Tagus salt marsh population presented higher annual belowground biomass and N productions, and a slower decomposition rate for litter, contributing to the higher N accumulation in the sediment, whereas S. maritima younger marshes had higher aboveground biomass production. Detritus moved by tides represented a huge amount of aboveground production, probably significant when considering the N balance of these salt marshes. Results reinforce the functions of salt marshes as contributing to a reduction of eutrophication in transitional waters, namely through sedimentation processes.


Assuntos
Eutrofização/fisiologia , Nitrogênio/metabolismo , Poaceae/metabolismo , Poluentes Químicos da Água/metabolismo , Áreas Alagadas , Biodegradação Ambiental , Biomassa , Ecossistema , Monitoramento Ambiental/métodos , Poaceae/crescimento & desenvolvimento , Portugal , Rios , Água do Mar
18.
Chemosphere ; 70(5): 850-7, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17764720

RESUMO

Salt marsh plants can sequestrate and inherently tolerate high metal concentrations found in salt marsh sediments. This work intended to understand the Halimione portulacoides (L.) Aellen strategies to prevent metal toxicity, by investigating the metal location in different plant organs and in the cell. A sequential extraction was performed on leaves, stems and roots of H. portulacoides in order to determine and compare the metal (Zn, Pb, Co, Cd, Ni and Cu) concentration in several fractions of the plant material (ethanolic, aqueous, proteic, pectic, polissacaridic, lenhinic and cellulosic). This study shows that all plant organs of H. portulacoides mostly retain metals in the cell wall (65% is the average for all studied metals stored in the root cell wall, 55% in the stems and 53% in the leaves), and the metal content in the intracellular compartment is much lower (21% in roots, 25% in stems and 32% in leaves). High levels of heavy metal in the sedimentary environment do not cause toxicity to H. portulacoides, because H. portulacoides immobilizes them in different cell compartments (cell wall+proteic fraction+intracellular) outside key metabolic sites.


Assuntos
Amaranthaceae/metabolismo , Espaço Extracelular/metabolismo , Sedimentos Geológicos/análise , Espaço Intracelular/metabolismo , Metais Pesados/farmacocinética , Poluentes Químicos da Água/farmacocinética , Áreas Alagadas , Amaranthaceae/química , Sítios de Ligação , Monitoramento Ambiental , Espaço Extracelular/química , Sedimentos Geológicos/química , Espaço Intracelular/química , Metais Pesados/metabolismo , Folhas de Planta/química , Folhas de Planta/metabolismo , Raízes de Plantas/química , Raízes de Plantas/metabolismo , Caules de Planta/química , Caules de Planta/metabolismo , Poluentes Químicos da Água/análise
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