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1.
J Environ Qual ; 49(3): 723-734, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-33016394

RESUMO

Groundwater withdrawal has increased over the past several decades throughout the U.S. Upper Midwest, yet impacts of pumping on groundwater-dependent wetlands remain understudied. Here, we compared measures of floristic quality, hydrologic conditions, and nutrient availability in pairs of more-impacted fens and less-impacted fens throughout Wisconsin. Floristic quality was significantly lower in more-impacted fens than in less-impacted fens, the result of the disappearance of rare and specialist species and the increase in richness and cover of non-native and weedy species. Plots within more-impacted fens generally had lower root-zone volumetric water content, greater depth to water table, and higher available nitrogen and phosphorus than within less-impacted fens, although nonuniformly among or within sites. Lower volumetric water content predicted plot-level declines in floristic quality, richness of rare or specialist species, an increase in the number of non-native or problematic species, and an increase in cover of non-native and problematic species. Our results strongly suggest that groundwater withdrawals have substantial negative impacts on nearby fen quality and furthering imperilment of several species they contain.


Assuntos
Água Subterrânea , Hidrologia , Nitrogênio , Áreas Alagadas , Wisconsin
2.
Sci Total Environ ; 693: 133484, 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31374507

RESUMO

Eutrophication of freshwaters occurs in watersheds with excessive pollution of phosphorus (P). Factors that affect P cycling and transport, including climate and land use, are changing rapidly and can have legacy effects, making future freshwater quality uncertain. Focusing on the Yahara Watershed (YW) of southern Wisconsin, USA, an intensive agricultural landscape, we explored the relative influence of land use and climate on three indicators of water quality over a span of 57 years (2014-2070). The indicators included watershed-averaged P yield from the land surface, direct drainage P loads to a lake, and average summertime lake P concentration. Using biophysical model simulations of future watershed scenarios, we found that climate exerted a stronger influence than land use on all three indicators, yet land use had an important role in influencing long term outcomes for each. Variations in P yield due to land use exceeded those due to climate in 36 of 57 years, whereas variations in load and lake total P concentration due to climate exceeded those due to land use in 54 of 57 years, and 52 of 57 years, respectively. The effect of land use was thus strongest for P yield off the landscape and attenuated in the stream and lake aquatic systems where the influence of weather variability was greater. Overall these findings underscore the dominant role of climate in driving inter-annual nutrient fluxes within the hydrologic network and suggest a challenge for land use to influence water quality within streams and lakes over timescales less than a decade. Over longer timescales, reducing applications of P throughout the watershed was an effective management strategy under all four climates investigated, even during decades with wetter conditions and more frequent extreme precipitation events.

3.
Ecol Appl ; 28(1): 119-134, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28944518

RESUMO

Sustaining food production, water quality, soil retention, flood, and climate regulation in agricultural landscapes is a pressing global challenge given accelerating environmental changes. Scenarios are stories about plausible futures, and scenarios can be integrated with biophysical simulation models to explore quantitatively how the future might unfold. However, few studies have incorporated a wide range of drivers (e.g., climate, land-use, management, population, human diet) in spatially explicit, process-based models to investigate spatial-temporal dynamics and relationships of a portfolio of ecosystem services. Here, we simulated nine ecosystem services (three provisioning and six regulating services) at 220 × 220 m from 2010 to 2070 under four contrasting scenarios in the 1,345-km2 Yahara Watershed (Wisconsin, USA) using Agro-IBIS, a dynamic model of terrestrial ecosystem processes, biogeochemistry, water, and energy balance. We asked (1) How does ecosystem service supply vary among alternative future scenarios? (2) Where on the landscape is the provision of ecosystem services most susceptible to future social-ecological changes? (3) Among alternative future scenarios, are relationships (i.e., trade-offs, synergies) among food production, water, and biogeochemical services consistent over time? Our results showed that food production varied substantially with future land-use choices and management, and its trade-offs with water quality and soil retention persisted under most scenarios. However, pathways to mitigate or even reverse such trade-offs through technological advances and sustainable agricultural practices were apparent. Consistent relationships among regulating services were identified across scenarios (e.g., trade-offs of freshwater supply vs. flood and climate regulation, and synergies among water quality, soil retention, and climate regulation), suggesting opportunities and challenges to sustaining these services. In particular, proactive land-use changes and management may buffer water quality against undesirable future climate changes, but changing climate may overwhelm management efforts to sustain freshwater supply and flood regulation. Spatially, changes in ecosystem services were heterogeneous across the landscape, underscoring the power of local actions and fine-scale management. Our research highlights the value of embracing spatial and temporal perspectives in managing ecosystem services and their complex interactions, and provides a system-level understanding for achieving sustainability of the food-water-climate nexus in agricultural landscapes.


Assuntos
Agricultura , Ecossistema , Desenvolvimento Sustentável , Wisconsin
4.
Popul Health Manag ; 18(3): 172-8, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25290852

RESUMO

Diabetes knows no age and affects millions of individuals. Preventing diabetes in children is increasingly becoming a major health policy concern and focus. The objective of this study is to project the number of children, aged 0-17 years, with diagnosed diabetes in the United States through 2030, accounting for changing demography, and diabetes and obesity prevalence rates. The study team combined historic diabetes and obesity prevalence data with US child population estimates and projections. A times-series regression model was used to forecast future diabetes prevalence and to account for the relationship between the forecasted diabetes prevalence and the lagged prevalence of childhood obesity. Overall, the prevalence of diagnosed diabetes is projected to increase 67% from 0.22% in 2010 to 0.36% in 2030. Lagged obesity prevalence in Hispanic boys and non-Hispanic black girls was significantly associated with increasing future diabetes prevalence. The study results showed that a 1% increase in obesity prevalence among Hispanic boys from the previous year was significantly associated with a 0.005% increase in future prevalence of diagnosed diabetes in children (P ≤ 0.01). Likewise, a unit increase in obesity prevalence among non-Hispanic black girls was associated with a 0.003% increase in future diabetes prevalence (P < 0.05). Obesity rates for other race/ethnicity combinations were not associated with increasing future diabetes prevalence. To mitigate the continued threat posed by diabetes, serious discussions need to focus on the pediatric population, particularly non-Hispanic black girls and Hispanic boys whose obesity trends show the strongest associations with future diabetes prevalence in children.


Assuntos
Diabetes Mellitus Tipo 1/epidemiologia , Diabetes Mellitus Tipo 2/epidemiologia , Obesidade Pediátrica/epidemiologia , Adolescente , Afro-Americanos/estatística & dados numéricos , Criança , Pré-Escolar , Diabetes Mellitus Tipo 1/etnologia , Diabetes Mellitus Tipo 2/etnologia , Feminino , Hispano-Americanos/estatística & dados numéricos , Humanos , Lactente , Recém-Nascido , Masculino , Inquéritos Nutricionais , Obesidade Pediátrica/etnologia , Prevalência , Análise de Regressão
5.
Glob Chang Biol ; 20(10): 3191-208, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24757012

RESUMO

Climate warming is projected to affect forest water yields but the effects are expected to vary. We investigated how forest type and age affect water yield resilience to climate warming. To answer this question, we examined the variability in historical water yields at long-term experimental catchments across Canada and the United States over 5-year cool and warm periods. Using the theoretical framework of the Budyko curve, we calculated the effects of climate warming on the annual partitioning of precipitation (P) into evapotranspiration (ET) and water yield. Deviation (d) was defined as a catchment's change in actual ET divided by P [AET/P; evaporative index (EI)] coincident with a shift from a cool to a warm period - a positive d indicates an upward shift in EI and smaller than expected water yields, and a negative d indicates a downward shift in EI and larger than expected water yields. Elasticity was defined as the ratio of interannual variation in potential ET divided by P (PET/P; dryness index) to interannual variation in the EI - high elasticity indicates low d despite large range in drying index (i.e., resilient water yields), low elasticity indicates high d despite small range in drying index (i.e., nonresilient water yields). Although the data needed to fully evaluate ecosystems based on these metrics are limited, we were able to identify some characteristics of response among forest types. Alpine sites showed the greatest sensitivity to climate warming with any warming leading to increased water yields. Conifer forests included catchments with lowest elasticity and stable to larger water yields. Deciduous forests included catchments with intermediate elasticity and stable to smaller water yields. Mixed coniferous/deciduous forests included catchments with highest elasticity and stable water yields. Forest type appeared to influence the resilience of catchment water yields to climate warming, with conifer and deciduous catchments more susceptible to climate warming than the more diverse mixed forest catchments.


Assuntos
Florestas , Transpiração Vegetal , Água , Mudança Climática , Fenômenos Geológicos , Hidrologia , Modelos Teóricos , América do Norte , Chuva , Temperatura
6.
Biotechnol Lett ; 35(4): 539-52, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23247570

RESUMO

The construction and testing of a unique instrument, the Paleobiosphere, which mimics some of the conditions of the ancient earth, is described. The instrument provides an experimental testing system for determining if certain microbes, when provided an adequate environment, can degrade biological materials to produce fuel-like hydrocarbons in a relatively short time frame that become trapped by the shale. The conditions selected for testing included a particulate Montana shale (serving as the "Trap Shale"), plant materials (leaves and stems of three extant species whose origins are in the late Cretaceous), a water-circulating system, sterile air, and a specially designed Carbotrap through which all air was passed as exhaust and volatile were hydrocarbons trapped. The fungus for initial testing was Annulohypoxylon sp., isolated as an endophyte of Citrus aurantifolia. It produces, in solid and liquid media, a series of hydrocarbon-like molecules. Some of these including 1,8-cineole, 2-butanone, propanoic acid, 2-methyl-, methyl ester, benzene (1-methylethyl)-, phenylethyl alcohol, benzophenone and azulene, 1,2,3,5,6,7,8,8a-octahydro-1,4-dimethyl-7-(1-methylethenyl), [1S-(1α,7α,8aß)]. These were the key signature compounds used in an initial Paleobiosphere test. After 3 weeks, incubation, the volatiles associated with the harvested "Trap Shale" included each of the signature substances as well as other fungal-associated products: some indanes, benzene derivatives, some cyclohexanes, 3-octanone, naphthalenes and others. The fungus thus produced a series of "Trap Shale" products that were representative of each of the major classes of hydrocarbons in diesel fuel (Mycodiesel). Initial tests with the Paleobiosphere offer some evidence for a possible origin of hydrocarbons trapped in bentonite shale. Thus, with modifications, numerous other tests can also be designed for utilization in the Paleobiosphere.


Assuntos
Biocombustíveis , Hidrocarbonetos/metabolismo , Citrus/microbiologia , Microbiologia Ambiental , Fósseis , Hidrocarbonetos/isolamento & purificação , Xylariales/metabolismo
7.
Microbiology (Reading) ; 158(Pt 2): 465-473, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22096148

RESUMO

An endophytic Hypoxylon sp. (strain CI-4) producing a wide spectrum of volatile organic compounds (VOCs), including 1,8-cineole, 1-methyl-1,4-cyclohexadiene and cyclohexane, 1,2,4-tris(methylene), was selected as a candidate for the modulation of VOC production. This was done in order to learn if the production of these and other VOCs can be affected by using agents that may modulate the epigenetics of the fungus. Many of the VOCs made by this organism are of interest because of their high energy densities and thus the potential they might have as Mycodiesel fuels. Strain CI-4 was exposed to the epigenetic modulators suberoylanilide hydroxamic acid (SAHA, a histone deacetylase) and 5-azacytidine (AZA, a DNA methyltransferase inhibitor). After these treatments the organism displayed striking cultural changes, including variations in pigmentation, growth rates and odour, in addition to significant differences in the bioactivities of the VOCs. The resulting variants were designated CI4-B, CI4-AZA and CI4-SAHA. GC/MS analyses of the VOCs produced by the variants showed considerable variation, with the emergence of several compounds not previously observed in the wild-type, particularly an array of tentatively identified terpenes such as α-thujene, sabinene, γ-terpinene, α-terpinolene and ß-selinene, in addition to several primary and secondary alkanes, alkenes, organic acids and derivatives of benzene. Proton transfer reaction mass spectroscopic analyses showed a marked increase in the ratio of ethanol (mass 47) to the total mass of all other ionizable VOCs, from ~0.6 in the untreated strain CI-4 to ~0.8 in CI-4 grown in the presence of AZA. Strain CI4-B was created by exposure of the fungus to 100 µM SAHA; upon removal of the epigenetic modulator from the culture medium, it did not revert to the wild-type phenotype. Results of this study have implications for understanding why there may be a wide range of VOCs found in various isolates of this fungus in nature.


Assuntos
Biocombustíveis/análise , Endófitos/metabolismo , Persea/microbiologia , Compostos Orgânicos Voláteis/metabolismo , Xylariales/metabolismo , Endófitos/genética , Endófitos/isolamento & purificação , Estrutura Molecular , Compostos Orgânicos Voláteis/química , Xylariales/genética , Xylariales/isolamento & purificação
8.
Biotechnol Lett ; 33(10): 1963-72, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21660573

RESUMO

A custom-made stainless steel column was designed to contain various materials that would trap the hydrocarbons and hydrocarbon derivatives during the processes of fungal fermentation ultimately yielding preparative amounts of volatile organic substances (VOCs). Trapping materials tested in the column were Carbotrap materials A and B (Supelco) as well as bentonite-shale from the oil bearing areas of Eastern Montana, the former allowed for the effective and efficient trapping of VOCs from purged cultures of Hypoxylon sp. Trapping efficiencies of various materials were measured by both gravimetric as well as proton transfer reaction mass spectroscopy with the Carbotraps A and B being 99% efficient when tested with known amounts of 1,8-cineole. Trapped fungal VOCs could effectively be removed and recovered via controlled heating of the stainless steel column followed by passage of the gases through a liquid nitrogen trap at a recovery rate of ca 65-70%. This method provides for the recovery of mg quantities of compounds normally present in the gas phase that may be needed for spectroscopy, bioassays and further separation and analysis and may have wide applicability for many other biological systems involving VOCs. Other available Carbotraps could be used for other applications.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Hidrocarbonetos/isolamento & purificação , Compostos Orgânicos Voláteis/isolamento & purificação , Xylariales/química , Bentonita , Cicloexanóis , Endófitos , Desenho de Equipamento , Eucaliptol , Cromatografia Gasosa-Espectrometria de Massas/instrumentação , Gases/análise , Hidrocarbonetos/química , Microscopia Eletrônica de Varredura , Monoterpenos , Compostos Orgânicos Voláteis/química
9.
Health Serv Res ; 46(6pt1): 1803-21, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21689095

RESUMO

OBJECTIVE: To investigate the relationship between Medicaid Personal Care Services (PCS) and caregivers' reports of activity (activities of daily living [ADL]) limitations for children with chronic health problems. DATA SOURCES/STUDY SETTING: Primary data collected in 2008 and 2009. A state Medicaid program was the setting. The focus was children receiving Medicaid PCS. DATA COLLECTION: Medicaid case managers assessed children to determine their need for PCS, using information provided by the child or informal caregivers. Two thousand seven hundred assessments were provided to researchers directly from case managers. PRINCIPAL FINDINGS: Medical conditions and impairments explained 58 percent of the variance in the child's activity limitations. Activity limitations and problem behaviors explained 28 percent of the variance in PCS hours authorized. Which case manager completed the assessment also played a substantial role in determining hours of care. CONCLUSIONS: Caregivers' reports of the severity of a child's activity limitations effectively summarize the effects of conditions and impairments on the child's ADL performance and have a significant impact on the level of services provided. Assessors often respond differently to children's characteristics and circumstances as they move from assessment to decisions concerning care provision. Our results imply that the provision of appropriate services may be enhanced when both case managers and caregivers play an active role in decisions concerning care provision.


Assuntos
Atividades Cotidianas , Cuidadores/organização & administração , Serviços de Assistência Domiciliar/organização & administração , Medicaid/organização & administração , Assistência Individualizada de Saúde/organização & administração , Adolescente , Adulto , Cuidadores/estatística & dados numéricos , Criança , Pré-Escolar , Feminino , Serviços de Assistência Domiciliar/estatística & dados numéricos , Humanos , Deficiência Intelectual , Masculino , Medicaid/estatística & dados numéricos , Variações Dependentes do Observador , Assistência Individualizada de Saúde/estatística & dados numéricos , Índice de Gravidade de Doença , Fatores Sexuais , Estados Unidos
10.
Microb Ecol ; 60(4): 903-14, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20953951

RESUMO

An endophytic fungus of Persea indica was identified, on the basis of its anamorphic stage, as Nodulosporium sp. by SEM. Partial sequence analysis of ITS rDNA revealed the identity of the teleomorphic stage of the fungus as Hypoxylon sp. It produces an impressive spectrum of volatile organic compounds (VOCs), most notably 1,8-cineole, 1-methyl-1,4-cyclohexadiene, and tentatively identified (+)-.alpha.-methylene-.alpha.-fenchocamphorone, among many others, most of which are unidentified. Six-day-old cultures of Hypoxylon sp. displayed maximal VOC-antimicrobial activity against Botrytis cinerea, Phytophthora cinnamomi, Cercospora beticola, and Sclerotinia sclerotiorum suggesting that the VOCs may play some role in the biology of the fungus and its survival in its host plant. Media containing starch- or sugar-related substrates best supported VOC production by the fungus. Direct on-line quantification of VOCs was measured by proton transfer mass spectrometry covering a continuous range with optimum VOC production occurred at 6 days at 145 ppmv with a rate of production of 7.65 ppmv/h. This report unequivocally demonstrates that 1,8-cineole (a monoterpene) is produced by a microorganism, which represents a novel and important source of this compound. This monoterpene is an octane derivative and has potential use as a fuel additive as do the other VOCs of this organism. Thus, fungal sourcing of this compound and other VOCs as produced by Hypoxylon sp. greatly expands their potential applications in medicine, industry, and energy production.


Assuntos
Cicloexanóis/metabolismo , Microbiologia Industrial , Monoterpenos/metabolismo , Persea/microbiologia , Compostos Orgânicos Voláteis/metabolismo , Xylariales/isolamento & purificação , Xylariales/fisiologia , Biocombustíveis/análise , Cicloexanóis/análise , Eucaliptol , Dados de Sequência Molecular , Monoterpenos/análise , Persea/fisiologia , Filogenia , Simbiose , Compostos Orgânicos Voláteis/análise , Xylariales/classificação , Xylariales/genética
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