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1.
Environ Sci Technol ; 57(30): 11067-11074, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37469326

RESUMO

The assumed dominance of chloride (Cl-) in terrestrial ecosystems is challenged by observations of extensive formation of organically bound Cl (Clorg), resulting in large soil Cl storage and internal cycling. Yet, little is known about the spatial distribution of Cl in ecosystems. We quantified patterns of Cl distribution in different habitats along a boreal hillslope moisture gradient ranging from relatively dry upland coniferous forests to wet discharge areas dominated by alder. We confirmed that dry habitats are important for Cl storage but found that Cl pools tended to be larger in moist and wet habitats. The storage of Clorg was less important in wet habitats, suggesting a shift in the balance between soil chlorination and dechlorination rates. Cl concentrations in the herb layer vegetation were high in wet and moist sites attributed to a shift in plant species composition, indicating plant community-dependent ecosystem Cl cycling. Mass-balance calculations showed that internal Cl cycling increased overall ecosystem Cl residence times at all sites and that plant uptake rates of Cl- were particularly high at wet sites. Our results indicate that habitat characteristics including plant communities and hydrology are key for understanding Cl cycling in the environment.


Assuntos
Ecossistema , Solo , Cloro/análise , Áreas Alagadas , Cloretos , Florestas , Plantas
2.
Sci Total Environ ; 711: 134561, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31818588

RESUMO

Climate change is predicted to have far reaching consequences for the mobility of carbon in arctic landscapes. On a regional scale, carbon cycling is highly dependent on interactions between terrestrial and aquatic parts of a catchment. Despite this, studies that integrate the terrestrial and aquatic systems and study entire catchments using site-specific data are rare. In this work, we use data partly published by Lindborg et al. (2016a) to calculate a whole-catchment carbon mass-balance budget for a periglacial catchment in West Greenland. Our budget shows that terrestrial net primary production is the main input of carbon (99% of input), and that most carbon leaves the system through soil respiration (90% of total export/storage). The largest carbon pools are active layer soils (53% of total carbon stock or 13 kg C m-2), permafrost soils (30% of total carbon stock or 7.6 kg C m-2) and lake sediments (13% of total carbon stock or 10 kg C m-2). Hydrological transport of carbon from the terrestrial to aquatic system is lower than in wetter climates, but the annual input of 4100 kg C yr-1 (or 3.5 g C m-2 yr-1) that enters the lake via runoff is still three times larger than the eolian input of terrestrial carbon. Due to the dry conditions, the hydrological export of carbon from the catchment is limited (5% of aquatic export/storage or 0.1% of total export/storage). Instead, CO2 evasion from the lake surface and sediment burial accounts for 57% and 38% of aquatic export/storage, respectively (or 0.8% and 0.5% of total export/storage), and Two-Boat Lake acts as a net source of carbon to the atmosphere. The limited export of carbon to downstream water bodies make our study system different from wetter arctic environments, where hydrological transport is an important export pathway for carbon.

3.
Sci Rep ; 8(1): 5452, 2018 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-29615662

RESUMO

Detection of endangered species is invaluable for conservation efforts, yet many traditional sampling techniques are ineffective at low population abundances or during certain periods of the year. Here, we compared results from a newly developed eDNA approach and the traditional observational method for the endangered pool frog (Pelophylax lessonae). Analysis using an occupancy-modeling framework indicated that the probability of pools being occupied using eDNA (0.93) was higher than for the traditional method of counting calling males and silent observed individuals (0.72). Detailed analysis revealed complementarity among the methods. That is, the traditional method gave a high rate of observation in June, whereas eDNA gave at least as many or more observations during other parts of the year. Discrepancies among the methods depended on the dominant lifecycle stage, and eDNA concentrations were higher when juveniles were present than at times when spawning occurred. eDNA concentrations were also positively related to P. lessonae observations. Our study demonstrates that an eDNA protocol for monitoring of endangered amphibian species can be particularly valuable during periods when individuals are hard to detect by observational methods, and provides guidance to sampling efforts for research and monitoring programs in other regions and systems.


Assuntos
DNA/análise , Monitoramento Ambiental/métodos , Ranidae/genética , Animais , Espécies em Perigo de Extinção , Probabilidade
4.
Ambio ; 42(4): 402-13, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23619798

RESUMO

Understanding how long-term abiotic and biotic processes are linked at a landscape level is of major interest for analyzing future impact on humans and the environment from present-day societal planning. This article uses results derived from multidisciplinary work at a coastal site in Sweden, with the aim of describing future landscape development. First, based on current and historical data, we identified climate change, shoreline displacement, and accumulation/erosion processes as the main drivers of landscape development. Second, site-specific information was combined with data from the Scandinavian region to build models that describe how the identified processes may affect the site development through time. Finally, the process models were combined to describe a whole interglacial period. With this article, we show how the landscape and ecosystem boundaries are affected by changing permafrost conditions, peat formation, sedimentation, human land use, and shoreline displacement.


Assuntos
Ecossistema , Gelo , Modelos Teóricos
5.
Int J Pharm ; 441(1-2): 316-22, 2013 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-23194882

RESUMO

A mechanistic model for the prediction of in-use moisture uptake of solid dosage forms in bottles is developed. The model considers moisture transport into the bottle and moisture uptake by the dosage form both when the bottle is closed and when it is open. Experiments are carried out by placing tablets and desiccant canisters in bottles and monitoring their moisture content. Each bottle is opened once a day to remove one tablet or desiccant canister. Opening the bottle to remove a tablet or canister also causes some exchange of air between the bottle headspace and the environment. In order to ascertain how this air exchange might depend on the customer, tablets and desiccant canisters are removed from the bottles by either carefully removing only one or by pouring all of the tablets or desiccant canisters out of the bottle, removing one, and pouring the remaining ones back into the bottle. The predictions of the model are found to be in good agreement with experimental data for moisture sorption by desiccant canisters. Moreover, it is found experimentally that the manner in which the tablets or desiccant canisters were removed does not appreciably affect their moisture content.


Assuntos
Dessecação , Embalagem de Medicamentos , Modelos Químicos , Preparações Farmacêuticas/química , Estabilidade de Medicamentos , Armazenamento de Medicamentos , Umidade , Comprimidos , Água/química
6.
J Food Sci ; 76(5): C714-23, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22417417

RESUMO

UNLABELLED: Tomatoes are often processed into shelf-stable products. However, the different processing steps might have an impact on the product quality. In this study, a model tomato soup was prepared and the impact of pilot-scale aseptic processing, including heat treatment and high-pressure homogenization, on some selected quality parameters was evaluated. The vitamin C content, the lycopene isomer content, and the lycopene bioaccessibility were considered as health-promoting attributes. As a structural characteristic, the viscosity of the tomato soup was investigated. A tomato soup without oil as well as a tomato soup containing 5% olive oil were evaluated. Thermal processing had a negative effect on the vitamin C content, while lycopene degradation was limited. For both compounds, high-pressure homogenization caused additional losses. High-pressure homogenization also resulted in a higher viscosity that was accompanied by a decrease in lycopene bioaccessibility. The presence of lipids clearly enhanced the lycopene isomerization susceptibility and improved the bioaccessibility. PRACTICAL APPLICATION: The results obtained in this study are of relevance for product formulation and process design of tomato-based food products.


Assuntos
Manipulação de Alimentos/métodos , Solanum lycopersicum/química , Ácido Ascórbico/análise , Carotenoides/análise , Temperatura Alta , Licopeno , Projetos Piloto , Reprodutibilidade dos Testes , Viscosidade
7.
Ambio ; 38(6): 316-24, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19860155

RESUMO

The aim of this study was to investigate a combination of satellite images of leaf area index (LAI) with process-based vegetation modeling for the accurate assessment of the carbon balances of Swedish forest ecosystems at the scale of a landscape. Monthly climatologic data were used as inputs in a dynamic vegetation model, the Lund Potsdam Jena-General Ecosystem Simulator. Model estimates of net primary production (NPP) and the fraction of absorbed photosynthetic active radiation were constrained by combining them with satellite-based LAI images using a general light use efficiency (LUE) model and the Beer-Lambert law. LAI estimates were compared with satellite-extrapolated field estimates of LAI, and the results were generally acceptable. NPP estimates directly from the dynamic vegetation model and estimates obtained by combining the model estimates with remote sensing information were, on average, well simulated but too homogeneous among vegetation types when compared with field estimates using forest inventory data.


Assuntos
Biodiversidade , Biomassa , Comunicações Via Satélite , Árvores , Carbono/análise , Conservação de Recursos Energéticos , Ecossistema , Agricultura Florestal , Geografia , Humanos , Modelos Biológicos , Dinâmica Populacional , Suécia
8.
PDA J Pharm Sci Technol ; 60(4): 254-8, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17089694

RESUMO

In order to illustrate current practice in aseptic blow-fill-seal (BFS) technology, a worldwide survey was performed by the BFS International Operators Association. The results are summarized and compared to the media fill data from the Product Quality and Research Institute (PQRI) survey reported in 2003. The survey highlights the differences and shows the robustness of the BFS technology. Compared to the results from the PQRI survey, the BFS survey shows a tenfold lower frequency of contaminated media fills.


Assuntos
Assepsia , Contaminação de Medicamentos/prevenção & controle , Indústria Farmacêutica , Armazenamento de Medicamentos , Assepsia/instrumentação , Assepsia/métodos , Assepsia/normas , Indústria Farmacêutica/instrumentação , Indústria Farmacêutica/métodos , Indústria Farmacêutica/normas , Armazenamento de Medicamentos/métodos , Armazenamento de Medicamentos/normas
9.
Ambio ; 35(8): 418-24, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17334049

RESUMO

To provide information necessary for a license application for a deep repository for spent nuclear fuel, the Swedish Nuclear Fuel and Waste Management Co. has started site investigations at two sites in Sweden. In this paper, we present a strategy to integrate site-specific ecosystem data into spatially explicit models needed for safety assessment studies and the environmental impact assessment. The site-specific description of ecosystems is developed by building discipline-specific models from primary data and by identifying interactions and stocks and flows of matter among functional units at the sites. The conceptual model is a helpful initial tool for defining properties needed to quantify system processes, which may reveal new interfaces between disciplines, providing a variety of new opportunities to enhance the understanding of the linkages between ecosystem characteristics and the functional properties of landscapes. This type of integrated ecosystem-landscape characterization model has an important role in forming the implementation of a safety assessment for a deep repository.


Assuntos
Ecossistema , Resíduos Radioativos , Gerenciamento de Resíduos/métodos , Licenciamento , Segurança , Suécia , Gerenciamento de Resíduos/normas
10.
Ambio ; 35(8): 459-68, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17334053

RESUMO

Ecosystem budgets of matter contribute to the assessment of transport and accumulation of bioavailable contaminants in a landscape, since flows of matter and energy ultimately determine the rates at which contaminants will be partitioned in the environment. This study compares ecosystem properties, such as net primary production (NPP), sequestration of matter and fluxes to food sources for humans, which are of potential interest to describe fluxes and accumulation of bioavailable radionuclides in 14 catchments within a larger catchment area in southeast Sweden. The carbon budgets, used as a proxy for organic matter, are mainly based on local estimates of pools and fluxes, which have been distributed across a landscape mosaic of different vegetation types and management regimes using a geographical information system (GIS). NPP varied by a factor close to two (432 - 709 g x Cx m(-2)x y(-1)), while net ecosystem production ranged between -124 and 159 gx C x m(-2) x y (-1) for the different catchments. Carbon sequestration mainly occurred in the vegetation while the soil organic carbon pool was mainly a source of carbon. Large herbivores consumed on average 4.5 % of the above-ground green tissue production. When arable land was present in the catchment, the flux of carbon to humans was highest from crops and, in decreasing order, milk and beef, followed by the flux from hunting and berry/fungus picking. The results can be used to estimate the potential assimilation of radionuclides in vegetation and the potential exposure to humans of bioavailable radionuclides.


Assuntos
Carbono/análise , Ecossistema , Monitoramento Ambiental/métodos , Modelos Teóricos , Radioisótopos/análise , Animais , Carbono/metabolismo , Humanos , Segurança , Suécia
11.
Ambio ; 35(8): 496-504, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17334057

RESUMO

To provide information necessary for a license application for a deep repository for spent nuclear fuel, the Swedish Nuclear Fuel and Waste Management Co is carrying out site investigations, including extensive studies of different parts of the surface ecosystems, at two sites in Sweden. Here we use the output from detailed modeling of the carbon dynamics in the terrestrial, limnic and marine ecosystems to describe and compare major pools and fluxes of organic matter in the Simpevarp area, situated on the southeast coast of Sweden. In this study, organic carbon is used as a proxy for radionuclides incorporated into organic matter. The results show that the largest incorporation of carbon into living tissue occurs in terrestrial catchments. Carbon is accumulated in soil or sediments in all ecosystems, but the carbon pool reaches the highest values in shallow near-land marine basins. The marine basins, especially the outer basins, are dominated by large horizontal water fluxes that transport carbon and any associated contaminants into the Baltic Sea. The results suggest that the near-land shallow marine basins have to be regarded as focal points for accumulation of radionuclides in the Simpevarp area, as they receive a comparatively large amount of carbon as discharge from terrestrial catchments, having a high NPP and a high detrital accumulation in sediments. These focal points may constitute a potential risk for exposure to humans in a future landscape as, due to post-glacial land uplift, previous accumulation bottoms are likely to be used for future agricultural purposes.


Assuntos
Ecossistema , Compostos Orgânicos , Resíduos Radioativos , Acetato de Megestrol , Segurança , Gerenciamento de Resíduos
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