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  • 1.
    Båmstedt, Ulf
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Brugel, Sonia
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    A cost-precision model for marine environmental monitoring, based on time-integrated averages2017Ingår i: Environmental Monitoring & Assessment, ISSN 0167-6369, E-ISSN 1573-2959, Vol. 189, nr 7, artikel-id 354Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Ongoing marine monitoring programs are seldom designed to detect changes in the environment between different years, mainly due to the high number of samples required for a sufficient statistical precision. We here show that pooling over time (time integration) of seasonal measurements provides an efficient method of reducing variability, thereby improving the precision and power in detecting inter-annual differences. Such data from weekly environmental sensor profiles at 21 stations in the northern Bothnian Sea was used in a cost-precision spatio-temporal allocation model. Time-integrated averages for six different variables over 6 months from a rather heterogeneous area showed low variability between stations (coefficient of variation, CV, range of 0.6-12.4%) compared to variability between stations in a single day (CV range 2.4-88.6%), or variability over time for a single station (CV range 0.4-110.7%). Reduced sampling frequency from weekly to approximately monthly sampling did not change the results markedly, whereas lower frequency differed more from results with weekly sampling. With monthly sampling, high precision and power of estimates could therefore be achieved with a low number of stations. With input of cost factors like ship time, labor, and analyses, the model can predict the cost for a given required precision in the time-integrated average of each variable by optimizing sampling allocation. A following power analysis can provide information on minimum sample size to detect differences between years with a required power. Alternatively, the model can predict the precision of annual means for the included variables when the program has a pre-defined budget. Use of time-integrated results from sampling stations with different areal coverage and environmental heterogeneity can thus be an efficient strategy to detect environmental differences between single years, as well as a long-term temporal trend. Use of the presented allocation model will then help to minimize the cost and effort of a monitoring program.

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  • 2.
    Haga, Susanna Lohman
    et al.
    Occupational and Environmental Medicine, School of Public Health and Community Medicine, Sahlgrenska Academy At University of Gothenburg, Gothenburg, Sweden.
    Hagenbjörk-Gustavsson, Annika
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Avdelningen för hållbar hälsa.
    Olin, Anna-Carin
    Occupational and Environmental Medicine, School of Public Health and Community Medicine, Sahlgrenska Academy At University of Gothenburg, Gothenburg, Sweden.
    Forsberg, Bertil
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Avdelningen för hållbar hälsa.
    Liljelind, Ingrid
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Avdelningen för hållbar hälsa.
    Carlsen, Hanne Krage
    Occupational and Environmental Medicine, School of Public Health and Community Medicine, Sahlgrenska Academy At University of Gothenburg, Gothenburg, Sweden.
    Modig, Lars
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Avdelningen för hållbar hälsa.
    Personal exposure levels to O3, NO x and PM10 and the association to ambient levels in two Swedish cities2021Ingår i: Environmental Monitoring & Assessment, ISSN 0167-6369, E-ISSN 1573-2959, Vol. 193, nr 10, artikel-id 674Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Exposure to air pollution is of great concern for public health although studies on the associations between exposure estimates and personal exposure are limited and somewhat inconsistent. The aim of this study was to quantify the associations between personal nitrogen oxides (NOx), ozone (O3) and particulate matter (PM10) exposure levels and ambient levels, and the impact of climate and time spent outdoors in two cities in Sweden. Subjects (n = 65) from two Swedish cities participated in the study. The study protocol included personal exposure measurements at three occasions, or waves. Personal exposure measurements were performed for NOx and O3 for 24 h and PM10 for 24 h, and the participants kept an activity diary. Stationary monitoring stations provided hourly data of NOx, O3 and PM, as well as data on air temperature and relative humidity. Data were analysed using mixed linear models with the subject-id as a random effect and stationary exposure and covariates as fixed effects. Personal exposure levels of NOx, O3 and PM10 were significantly associated with levels measured at air pollution monitoring stations. The associations persisted after adjusting for temperature, relative humidity, city and wave, but the modelled estimates were slightly attenuated from 2.4% (95% CI 1.8–2.9) to 2.0% (0.97–2.94%) for NOx, from 3.7% (95% CI 3.1–4.4) to 2.1% (95% CI 1.1–2.9%) for O3 and from 2.6% (95% 0.9–4.2%) to 1.3% (95% CI − 1.5–4.0) for PM10. After adding covariates, the degree of explanation offered by the model (coefficient of determination, or R2) did not change for NOx (0.64 to 0.63) but increased from 0.46 to 0.63 for O3, and from 0.38 to 0.43 for PM10. Personal exposure to NOx, O3 and PM has moderate to good association with levels measured at urban background sites. The results indicate that stationary measurements are valid as measure of exposure in environmental health risk assessments, especially if they can be refined using activity diaries and meteorological data. Approximately 50–70% of the variation of the personal exposure was explained by the stationary measurement, implying occurrence of misclassification in studies using more crude exposure metrics, potentially leading to underestimates of the effects of exposure to ambient air pollution.

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  • 3.
    Hagenbjörk, Annika
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Yrkes- och miljömedicin.
    Malmqvist, E
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Avdelningen för medicin.
    Mattisson, K
    Sommar, Nilsson J.
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Yrkes- och miljömedicin.
    Modig, Lars
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Yrkes- och miljömedicin.
    The spatial variation of O3, NO, NO2 and NOx and the relation between them in two Swedish cities2017Ingår i: Environmental Monitoring & Assessment, ISSN 0167-6369, E-ISSN 1573-2959, Vol. 189, nr 4, artikel-id 161Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Ozone and nitrogen oxides (NO x ) are air pollutants with known associations to adverse health effects on humans. Few studies have simultaneously measured ozone and nitrogen oxides with high spatial resolution. The main aim of this paper was to assess the levels and variation of ground-level ozone, NO2 and NO x in two Swedish cities. An additional aim was to describe the levels of these pollutants within and between three different types of measurement sites (regional background, urban background and traffic sites) and within and between different measurement periods of the year. Three weekly sampling campaigns of NO x and ozone were conducted simultaneously at 20 sites in two Swedish regions using Ogawa badges. Ozone was measured at 20 additional sites in each area. The median ozone concentration for all measurements was statistically significantly higher in Malmö (67 μg/m(3)) compared to Umeå (56 μg/m(3)), and in both cities, ozone levels were highest in April. Measurement period was a more important factor for describing the variation in ozone concentrations than the type of measurement site. The levels of NO2 and NO x were statistically significantly higher in the Malmö area (8.1 and 12 μg/m(3)) compared to the Umeå area (4.5 and 8.9 μg/m(3)). The levels were generally highest at the sites categorized as traffic, while the variability between different seasons was sparse.

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  • 4.
    Löfgren, Stefan
    et al.
    Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, Uppsala, Sweden .
    Fröberg, Mats
    Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, Uppsala, Sweden .
    Yu, Jun
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för matematik och matematisk statistik.
    Nisell, Jakob
    Geological Survey of Sweden, Uppsala, Sweden.
    Ranneby, Bo
    Centre of Biostochastics, Swedish University of Agricultural Sciences, Umeå, Sweden .
    Water chemistry in 179 randomly selected Swedish headwaterstreams related to forest production, clear-felling and climate2014Ingår i: Environmental Monitoring & Assessment, ISSN 0167-6369, E-ISSN 1573-2959, Vol. 186, nr 12, s. 8907-8928Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    From a policy perspective, it is important to understand forestry effects on surface waters from a landscape perspective. The EU Water Framework Directive demands remedial actions if not achieving good ecological status. In Sweden, 44 % of the surface water bodies have moderate ecological status or worse. Many of these drain catchments with a mosaic of managed forests. It is important for the forestry sector and water authorities to be able to identify where, in the forested landscape, special precautions are necessary. The aim of this study was to quantify the relations between forestry parameters and headwater stream concentrations of nutrients, organic matter and acid-base chemistry. The results are put into the context of regional climate, sulphur and nitrogen deposition, as well as marine influences. Water chemistry was measured in 179 randomly selected headwater streams from two regions in southwest and central Sweden, corresponding to 10 % of the Swedish land area. Forest status was determined from satellite images and Swedish National Forest Inventory data using the probabilistic classifier method, which was used to model stream water chemistry with Bayesian model averaging. The results indicate that concentrations of e.g. nitrogen, phosphorus and organic matter are related to factors associated with forest production but that it is not forestry per se that causes the excess losses. Instead, factors simultaneously affecting forest production and stream water chemistry, such as climate, extensive soil pools and nitrogen deposition, are the most likely candidates The relationships with clear-felled and wetland areas are likely to be direct effects.

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  • 5.
    Nagahage, Isura Sumeda Priyadarshana
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Graduate School of Science and Engineering, Saitama University, 255 Shimo-Okubo, Sakura-ku, Saitama, Japan.
    Nagahage, Ekanayaka Achchillage Ayesha Dilrukshi
    Graduate School of Science and Engineering, Saitama University, 255 Shimo-Okubo, Sakura-ku, Saitama, Japan.
    Fujino, Takeshi
    Graduate School of Science and Engineering, Saitama University, 255 Shimo-Okubo, Sakura-ku, Saitama, Japan.
    Assessment of the applicability of a low-cost sensor–based methane monitoring system for continuous multi-channel sampling2021Ingår i: Environmental Monitoring & Assessment, ISSN 0167-6369, E-ISSN 1573-2959, Vol. 193, nr 8, artikel-id 509Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Systems that are made of several low-cost gas sensors with automatic gas sampling may have the potential to serve as reliable fast methane analyzers. However, there is a lack of reports about such types of systems evaluated under field conditions. Here, we developed a continuous methane monitoring system with automated gas sampling unit using low-cost gas sensors, TGS 2611 and MQ-4, that use a simple cloud-based data acquisition platform. We verified the consistency, repeatability, and reproducibility of the data obtained by TGS 2611 and MQ-4 low-cost gas sensors by measuring high- and low-concentration methane samples. The normalized root-mean-square errors (NRMSEs) of the samples with high methane concentrations, [CH4] of 3, 4, 6, and 7%, were 0.0788, 0.0696, 0.1198, and 0.0719 for the TGS 2611 sensor, respectively, and were confirmed using a gas chromatograph as a reference analyzer. The NRMSEs of the samples with low [CH4] of 0.096, 0.145, 0.193, and 0.241% measured by the TGS 2611 sensor were 0.0641, 0.1749, 0.0157, and 0.1613, whereas those NRMSEs of the same concentrations measured by the MQ-4 sensor were 0.3143, 0.5766, 0.6301, and 0.6859, respectively. Laboratory-scale anaerobic digesters were tested using the developed system. The anaerobic digesters were continuously operated for 2 months, demonstrating the potential use of sensors for detecting and monitoring methane in the field level application. This study utilized a unique way to combine the advantages of low-cost sensors and develop a reliable monitoring system by minimizing drawbacks of low-cost sensors.

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  • 6. Orru, Mall
    et al.
    Ots, Katri
    Orru, Hans
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Yrkes- och miljömedicin. Department of Family Medicine and Public Health, University of Tartu, Tartu, Estonia.
    Re-vegetation processes in cutaway peat production fields in Estonia in relation to peat quality and water regime2016Ingår i: Environmental Monitoring & Assessment, ISSN 0167-6369, E-ISSN 1573-2959, Vol. 188, nr 12, artikel-id 655Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Eighty-one cutaway peat production fields with a total area of about 9000 ha exist and were studied in Estonia in 2005-2015. Only a very small number of the fields (seven) have been restored-either afforested or used for growing berries. The re-vegetation of Estonian cutaway peat production fields is mainly the result of natural processes, which are generally very slow due to an unfavourable water regime or a too thin remaining peat layer. The fields are mostly covered by cotton grass and birches. Often sparse vegetation covers 15-20% of a peat field, but some fields have turned into heaths or grasslands with plant coverage up to 60%. However, due to changes in environmental (mainly hydrological) conditions and peat characteristics (mainly peat type), these areas can also be new niches for several species. A number of moss species new to or rare in Estonia, e.g. Pohlia elongata, Ephemerum serratum, Campylopus introflexus and Bryum oblongum, were recorded.

  • 7. Ståhl, Göran
    et al.
    Allard, Anna
    Esseen, Per-Anders
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Glimskär, Anders
    Ringvall, Anna
    Svensson, Johan
    Sundquist, Sture
    Christensen, Pernilla
    Gallegos Torell, Åsa
    Högström, Mats
    Lagerqvist, Kjell
    Marklund, Liselott
    Nilsson, Björn
    Inghe, Ola
    National inventory of landscapes in Sweden (NILS): scope, design, and experiences from establishing a multi-scale biodiversity monitoring system2011Ingår i: Environmental Monitoring & Assessment, ISSN 0167-6369, E-ISSN 1573-2959, Vol. 173, nr 1-4, s. 579-595Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The landscape-level and multiscale biodiversity monitoring program National Inventory of Landscapes in Sweden (NILS) was launched in 2003. NILS is conducted as a sample-based stratified inventory that acquires data across several spatial scales, which is accomplished by combining aerial photo interpretation with field inventory. A total of 631 sample units are distributed across the land base of Sweden, of which 20% are surveyed each year. By 2007 NILS completed the first 5-year inventory phase. As the reinventory in the second 5-year phase (2008-2012) proceeds, experiences and insights accumulate and reflections are made on the setup and accomplishment of the monitoring scheme. In this article, the emphasis is placed on background, scope, objectives, design, and experiences of the NILS program. The main objective to collect data for and perform analyses of natural landscape changes, degree of anthropogenic impact, prerequisites for natural biological diversity and ecological processes at landscape scale. Different environmental conditions that can have direct or indirect effects on biological diversity are monitored. The program provides data for national and international policy and offers an infrastructure for other monitoring program and research projects. NILS has attracted significant national and international interest during its relatively short time of existence; the number of stakeholders and cooperation partners steadily increases. This is constructive and strengthens the incentive for the multiscale monitoring approach.

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