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1.
Science ; 377(6605): 523-527, 2022 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-35901146

RESUMO

Much uncertainty exists about the vulnerability of valuable tidal marsh ecosystems to relative sea level rise. Previous assessments of resilience to sea level rise, to which marshes can adjust by sediment accretion and elevation gain, revealed contrasting results, depending on contemporary or Holocene geological data. By analyzing globally distributed contemporary data, we found that marsh sediment accretion increases in parity with sea level rise, seemingly confirming previously claimed marsh resilience. However, subsidence of the substrate shows a nonlinear increase with accretion. As a result, marsh elevation gain is constrained in relation to sea level rise, and deficits emerge that are consistent with Holocene observations of tidal marsh vulnerability.


Assuntos
Elevação do Nível do Mar , Áreas Alagadas , Incerteza
3.
PLoS One ; 16(7): e0253554, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34270570

RESUMO

Wetlands along upper estuaries are characterized by dynamic transitions between forested and herbaceous communities (marsh) as salinity, hydroperiod, and nutrients change. The importance of belowground net primary productivity (BNPP) associated with fine and coarse root growth also changes but remains the dominant component of overall productivity in these important blue carbon wetlands. Appropriate BNPP assessment techniques to use in various tidal wetlands are not well-defined, and could make a difference in BNPP estimation. We hypothesized that different BNPP techniques applied among tidal wetlands differ in estimation of BNPP and possibly also correlate differently with porewater nutrient concentrations. We compare 6-month and 12-month root ingrowth, serial soil coring techniques utilizing two different calculations, and a mass balance approach (TBCA, Total Belowground Carbon Allocation) among four tidal wetland types along each of two river systems transitioning from freshwater forest to marsh. Median values of BNPP were 266 to 2946 g/m2/year among all techniques used, with lower BNPP estimation from root ingrowth cores and TBCA (266-416 g/m2/year), and higher BNPP estimation from serial coring of standing crop root biomass (using Smalley and Max-Min calculation methods) (2336-2946 g/m2/year). Root turnover (or longevity) to a soil depth of 30 cm was 2.2/year (1.3 years), 2.7/year (1.1 years), 4.5/year (0.9 years), and 1.2/year (2.6 years), respectively, for Upper Forest, Middle Forest, Lower Forest, and Marsh. Marsh had greater root biomass and BNPP, with slower root turnover (greater root longevity) versus forested wetlands. Soil porewater concentrations of NH3 and reactive phosphorus stimulated BNPP in the marsh when assessed with short-deployment BNPP techniques, indicating that pulses of mineralized nutrients may stimulate BNPP to facilitate marsh replacement of forested wetlands. Overall, ingrowth techniques appeared to represent forested wetland BNPP adequately, while serial coring may be necessary to represent herbaceous plant BNPP from rhizomes as marshes replace forested wetlands.


Assuntos
Água Doce , Solo , Áreas Alagadas , Carbono/análise , Ecossistema , Florestas , Salinidade
4.
Sci Rep ; 10(1): 14652, 2020 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-32887898

RESUMO

Mangrove forests provide many ecosystem services but are among the world's most threatened ecosystems. Mangroves vary substantially according to their geomorphic and sedimentary setting; while several conceptual frameworks describe these settings, their spatial distribution has not been quantified. Here, we present a new global mangrove biophysical typology and show that, based on their 2016 extent, 40.5% (54,972 km2) of mangrove systems were deltaic, 27.5% (37,411 km2) were estuarine and 21.0% (28,493 km2) were open coast, with lagoonal mangroves the least abundant (11.0%, 14,993 km2). Mangroves were also classified based on their sedimentary setting, with carbonate mangroves being less abundant than terrigenous, representing just 9.6% of global coverage. Our typology provides a basis for future research to incorporate geomorphic and sedimentary setting in analyses. We present two examples of such applications. Firstly, based on change in extent between 1996 and 2016, we show while all types exhibited considerable declines in area, losses of lagoonal mangroves (- 6.9%) were nearly twice that of other types. Secondly, we quantify differences in aboveground biomass between mangroves of different types, with it being significantly lower in lagoonal mangroves. Overall, our biophysical typology provides a baseline for assessing restoration potential and for quantifying mangrove ecosystem service provision.


Assuntos
Conservação dos Recursos Naturais , Áreas Alagadas , Biomassa , Carbono/análise , Carbonatos/análise , Mudança Climática , Sedimentos Geológicos/química , Solo/química
6.
Ecol Appl ; 30(4): e02085, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31991504

RESUMO

Mangrove forests are among the world's most productive and carbon-rich ecosystems. Despite growing understanding of factors controlling mangrove forest soil carbon stocks, there is a need to advance understanding of the speed of peat development beneath maturing mangrove forests, especially in created and restored mangrove forests that are intended to compensate for ecosystem functions lost during mangrove forest conversion to other land uses. To better quantify the rate of soil organic matter development beneath created, maturing mangrove forests, we measured ecosystem changes across a 25-yr chronosequence. We compared ecosystem properties in created, maturing mangrove forests to adjacent natural mangrove forests. We also quantified site-specific changes that occurred between 2010 and 2016. Soil organic matter accumulated rapidly beneath maturing mangrove forests as sandy soils transitioned to organic-rich soils (peat). Within 25 yr, a 20-cm deep peat layer developed. The time required for created mangrove forests to reach equivalency with natural mangrove forests was estimated as (1) <15 yr for herbaceous and juvenile vegetation, (2) ~55 yr for adult trees, (3) ~25 yr for the upper soil layer (0-10 cm), and (4) ~45-80 yr for the lower soil layer (10-30 cm). For soil elevation change, the created mangrove forests were equivalent to or surpassed natural mangrove forests within the first 5 yr. A comparison to chronosequence studies from other ecosystems indicates that the rate of soil organic matter accumulation beneath maturing mangrove forests may be among the fastest globally. In most peatland ecosystems, soil organic matter formation occurs slowly (over centuries, millennia); however, these results show that mangrove peat formation can occur within decades. Peat development, primarily due to subsurface root accumulation, enables mangrove forests to sequester carbon, adjust their elevation relative to sea level, and adapt to changing conditions at the dynamic land-ocean interface. In the face of climate change and rising sea levels, coastal managers are increasingly concerned with the longevity and functionality of coastal restoration efforts. Our results advance understanding of the pace of ecosystem development in created, maturing mangrove forests, which can improve predictions of mangrove forest responses to global change and ecosystem restoration.


Assuntos
Ecossistema , Áreas Alagadas , Carbono , Mudança Climática , Florestas , Solo
7.
PLoS One ; 12(9): e0183431, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28902904

RESUMO

Coastal wetland responses to sea-level rise are greatly influenced by biogeomorphic processes that affect wetland surface elevation. Small changes in elevation relative to sea level can lead to comparatively large changes in ecosystem structure, function, and stability. The surface elevation table-marker horizon (SET-MH) approach is being used globally to quantify the relative contributions of processes affecting wetland elevation change. Historically, SET-MH measurements have been obtained at local scales to address site-specific research questions. However, in the face of accelerated sea-level rise, there is an increasing need for elevation change network data that can be incorporated into regional ecological models and vulnerability assessments. In particular, there is a need for long-term, high-temporal resolution data that are strategically distributed across ecologically-relevant abiotic gradients. Here, we quantify the distribution of SET-MH stations along the northern Gulf of Mexico coast (USA) across political boundaries (states), wetland habitats, and ecologically-relevant abiotic gradients (i.e., gradients in temperature, precipitation, elevation, and relative sea-level rise). Our analyses identify areas with high SET-MH station densities as well as areas with notable gaps. Salt marshes, intermediate elevations, and colder areas with high rainfall have a high number of stations, while salt flat ecosystems, certain elevation zones, the mangrove-marsh ecotone, and hypersaline coastal areas with low rainfall have fewer stations. Due to rapid rates of wetland loss and relative sea-level rise, the state of Louisiana has the most extensive SET-MH station network in the region, and we provide several recent examples where data from Louisiana's network have been used to assess and compare wetland vulnerability to sea-level rise. Our findings represent the first attempt to examine spatial gaps in SET-MH coverage across abiotic gradients. Our analyses can be used to transform a broadly disseminated and unplanned collection of SET-MH stations into a coordinated and strategic regional network. This regional network would provide data for predicting and preparing for the responses of coastal wetlands to accelerated sea-level rise and other aspects of global change.


Assuntos
Mudança Climática , Ecossistema , Monitoramento Ambiental/normas , Água do Mar , Áreas Alagadas , Alabama , Monitoramento Ambiental/métodos , Florida , Golfo do México , Serviços de Informação/organização & administração , Serviços de Informação/normas , Louisiana , Mississippi , Projetos de Pesquisa/normas , Estudos de Amostragem , Texas
8.
Stroke ; 48(11): 3101-3107, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28954922

RESUMO

BACKGROUND AND PURPOSE: The Centers for Medicare & Medicaid Services publicly reports a hospital-level stroke mortality measure that lacks stroke severity risk adjustment. Our objective was to describe novel measures of stroke mortality suitable for public reporting that incorporate stroke severity into risk adjustment. METHODS: We linked data from the American Heart Association/American Stroke Association Get With The Guidelines-Stroke registry with Medicare fee-for-service claims data to develop the measures. We used logistic regression for variable selection in risk model development. We developed 3 risk-standardized mortality models for patients with acute ischemic stroke, all of which include the National Institutes of Health Stroke Scale score: one that includes other risk variables derived only from claims data (claims model); one that includes other risk variables derived from claims and clinical variables that could be obtained from electronic health record data (hybrid model); and one that includes other risk variables that could be derived only from electronic health record data (electronic health record model). RESULTS: The cohort used to develop and validate the risk models consisted of 188 975 hospital admissions at 1511 hospitals. The claims, hybrid, and electronic health record risk models included 20, 21, and 9 risk-adjustment variables, respectively; the C statistics were 0.81, 0.82, and 0.79, respectively (as compared with the current publicly reported model C statistic of 0.75); the risk-standardized mortality rates ranged from 10.7% to 19.0%, 10.7% to 19.1%, and 10.8% to 20.3%, respectively; the median risk-standardized mortality rate was 14.5% for all measures; and the odds of mortality for a high-mortality hospital (+1 SD) were 1.51, 1.52, and 1.52 times those for a low-mortality hospital (-1 SD), respectively. CONCLUSIONS: We developed 3 quality measures that demonstrate better discrimination than the Centers for Medicare & Medicaid Services' existing stroke mortality measure, adjust for stroke severity, and could be implemented in a variety of settings.


Assuntos
Isquemia Encefálica/mortalidade , Modelos Biológicos , Índice de Gravidade de Doença , Acidente Vascular Cerebral/mortalidade , Demandas Administrativas em Assistência à Saúde , Idoso , Idoso de 80 Anos ou mais , Isquemia Encefálica/parasitologia , Isquemia Encefálica/patologia , Registros Eletrônicos de Saúde , Feminino , Humanos , Masculino , Medicare , Estudos Retrospectivos , Fatores de Risco , Acidente Vascular Cerebral/patologia , Acidente Vascular Cerebral/fisiopatologia , Fatores de Tempo , Estados Unidos
9.
Ecology ; 98(8): 2003-2018, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28489250

RESUMO

Coastal wetlands significantly contribute to global carbon storage potential. Sea-level rise and other climate-change-induced disturbances threaten coastal wetland sustainability and carbon storage capacity. It is critical that we understand the mechanisms controlling wetland carbon loss so that we can predict and manage these resources in anticipation of climate change. However, our current understanding of the mechanisms that control soil organic matter decomposition, in particular the impacts of elevated salinity, are limited, and literature reports are contradictory. In an attempt to improve our understanding of these complex processes, we measured root and rhizome decomposition and developed a causal model to identify and quantify the mechanisms that influence soil organic matter decomposition in coastal wetlands that are impacted by sea-level rise. We identified three causal pathways: (1) a direct pathway representing the effects of flooding on soil moisture, (2) a direct pathway representing the effects of salinity on decomposer microbial communities and soil biogeochemistry, and (3) an indirect pathway representing the effects of salinity on litter quality through changes in plant community composition over time. We used this model to test the effects of alternate scenarios on the response of tidal freshwater forested wetlands and oligohaline marshes to short- and long-term climate-induced disturbances of flooding and salinity. In tidal freshwater forested wetlands, the model predicted less decomposition in response to drought, hurricane salinity pulsing, and long-term sea-level rise. In contrast, in the oligohaline marsh, the model predicted no change in response to drought and sea-level rise, and increased decomposition following a hurricane salinity pulse. Our results show that it is critical to consider the temporal scale of disturbance and the magnitude of exposure when assessing the effects of salinity intrusion on carbon mineralization in coastal wetlands. Here, we identify three causal mechanisms that can reconcile disparities between long-term and short-term salinity impacts on organic matter decomposition.


Assuntos
Inundações , Salinidade , Solo/química , Áreas Alagadas , Água Doce
10.
Sci Rep ; 7(1): 1030, 2017 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-28432292

RESUMO

Mangrove wetlands provide ecosystem services for millions of people, most prominently by providing storm protection, food and fodder. Mangrove wetlands are also valuable ecosystems for promoting carbon (C) sequestration and storage. However, loss of mangrove wetlands and these ecosystem services are a global concern, prompting the restoration and creation of mangrove wetlands as a potential solution. Here, we investigate soil surface elevation change, and its components, in created mangrove wetlands over a 25 year developmental gradient. All created mangrove wetlands were exceeding current relative sea-level rise rates (2.6 mm yr-1), with surface elevation change of 4.2-11.0 mm yr-1 compared with 1.5-7.2 mm yr-1 for nearby reference mangroves. While mangrove wetlands store C persistently in roots/soils, storage capacity is most valuable if maintained with future sea-level rise. Through empirical modeling, we discovered that properly designed creation projects may not only yield enhanced C storage, but also can facilitate wetland persistence perennially under current rates of sea-level rise and, for most sites, for over a century with projected medium accelerations in sea-level rise (IPCC RCP 6.0). Only the fastest projected accelerations in sea-level rise (IPCC RCP 8.5) led to widespread submergence and potential loss of stored C for created mangrove wetlands before 2100.

11.
Health (London) ; 21(1): 21-37, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-28064539

RESUMO

This article reports the results of a Foucauldian-informed discourse analysis exploring representations of fatness embedded within an empirically based psychological treatment manual for binge eating disorder, a condition characterized by overvaluation of weight and shape. Analyses indicate that the manual prioritizes weight loss with relatively less emphasis placed on treating the diagnostic symptoms and underlying mechanisms of binge eating disorder. We raise critical concerns about these observations and link our findings to mainstream psychology's adoption of the medical framing of fatness as obesity within the "gold standard" approach to intervention. We recommend that psychology as a discipline abandons the weight loss imperative associated with binge eating disorder and fat bodies. We recommend that practitioners locate the problem of fat shame in society as opposed to the individual person's body and provide individuals with tools to identify and resist fat stigma and oppression, rather than provide them with tools to reshape their bodies.


Assuntos
Transtorno da Compulsão Alimentar/terapia , Protocolos Clínicos/normas , Obesidade/terapia , Psicologia Clínica/normas , Transtorno da Compulsão Alimentar/diagnóstico , Imagem Corporal/psicologia , Peso Corporal/fisiologia , Humanos , Obesidade/psicologia , Psicologia Clínica/métodos , Autoimagem , Redução de Peso/fisiologia
12.
Cult Health Sex ; 19(4): 422-437, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27650039

RESUMO

Contemporary social theorists emphasise the cultural quest for authenticity under conditions of increasing artificiality. Within this context, the body is commonly treated as an 'unfinished' surface requiring ongoing transformation to fulfil identity obligations. In this paper, we examine one such identity authentication project in the form of marketing of men's sexuopharmaceuticals. We use online pharmaceutical advertising for four approved sexuopharmaceuticals (Viagra, Cialis, STAXYN and Stendra) to describe the ideal neoliberal consumer. These campaigns underscore the robust role of pharmaceuticals in sexual authentication projects undergirded by neoliberal consumerist and aspirationalist ideals. Penile dependability as a luxury consumerist project reinvigorates traditional sexual (masculine) authentication as yoked to phallic control, by repackaging sexual enhancement medication use as a neoliberal beacon of aspirational achievements. The ideal targeted user is increasingly younger, and consumption of sexuopharmaceuticals is represented as achieving elite status and exclusive pleasures; masculine authenticity and choice; progressive relationships and a contemporary urban, fast-paced life; and a prepared yet spontaneous romantic sexuality. Women are also increasingly used in promotional materials directed at men; their responsibility centres on coaching and coaxing potential users.


Assuntos
Publicidade/métodos , Indústria Farmacêutica/métodos , Disfunção Erétil/tratamento farmacológico , Masculinidade , Homens/psicologia , Disfunção Erétil/psicologia , Humanos , Internet , Relações Interpessoais , Masculino , Prazer , Comportamento Sexual/psicologia , Sexualidade/psicologia , Agentes Urológicos/administração & dosagem
15.
J Interpers Violence ; 27(11): 2128-43, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22258070

RESUMO

Understanding the developmental precursors of juvenile violent sex offending can contribute to the promotion of effective early intervention and prevention programs for high-risk children and youth. However, there is currently a lack of research on the early characteristics of adolescents who commit violent sex offenses. Drawing on the literature regarding the generalist and specialist positions of criminal behavior, the aim of the present study was to compare childhood risk factors for three groups of juvenile offenders: (a) pure sex offenders (PSO; n = 28); (b) violent non-sex offenders (VNSO; n = 172); and (c) versatile violent sex offenders (VVSO; n = 24). Nineteen risk factors comprising four life domains (individual, family, peer, and school) were identified from a file review. Three hierarchical logistic regression analyses examined associations between risk factors and offender groups. The results reflected the underlying heterogeneity of the sample, offering support for both the specialist and generalist positions of criminal behavior. PSOs differed from VNSOs on the basis of higher odds for precocious sexual behavior. Second, VVSOs differed from VNSOs on the basis of higher odds for precocious sexual behavior, criminal family members, and an adolescent mother, as well as lower odds for poor school behavior. Third, PSOs were marginally more likely to have engaged in early overt antisocial behavior compared with VVSOs. Fourth, many of the childhood risk factors examined were not associated with any offender group. In conclusion, VVSOs appeared to differ on the greatest number of risk factors from VNSOs, suggesting that VVSOs share a more similar developmental pathway with PSOs. The prevention and future research implications of these findings are discussed.


Assuntos
Comportamento do Adolescente/psicologia , Delitos Sexuais/psicologia , Violência/psicologia , Adolescente , Criança , Relações Familiares , Humanos , Masculino , Relações Pais-Filho , Fatores de Risco , Comportamento Sexual
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