| 1. |
- Ahlberg, Erik, et al.
(författare)
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"Vi klimatforskare stödjer Greta och skolungdomarna"
- 2019
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Ingår i: Dagens nyheter (DN debatt). - 1101-2447.
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Tidskriftsartikel (populärvet., debatt m.m.)abstract
- DN DEBATT 15/3. Sedan industrialiseringens början har vi använt omkring fyra femtedelar av den mängd fossilt kol som får förbrännas för att vi ska klara Parisavtalet. Vi har bara en femtedel kvar och det är bråttom att kraftigt reducera utsläppen. Det har Greta Thunberg och de strejkande ungdomarna förstått. Därför stödjer vi deras krav, skriver 270 klimatforskare.
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| 2. |
- Andersson-Sköld, Yvonne, et al.
(författare)
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A framework for assessing urban greenery's effects and valuing its ecosystem services
- 2018
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Ingår i: Journal of Environmental Management. - : Academic Press. - 0301-4797 .- 1095-8630. ; 205, s. 274-285
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Tidskriftsartikel (refereegranskat)abstract
- Ongoing urban exploitation is increasing pressure to transform urban green spaces, while there is increasing awareness that greenery provides a range of important benefits to city residents. In efforts to help resolve associated problems we have developed a framework for integrated assessments of ecosystem service (ES) benefits and values provided by urban greenery, based on the ecosystem service cascade model. The aim is to provide a method for assessing the contribution to, and valuing, multiple ES provided by urban greenery that can be readily applied in routine planning processes. The framework is unique as it recognizes that an urban greenery comprises several components and functions that can contribute to multiple ecosystem services in one or more ways via different functional traits (e.g. foliage characteristics) for which readily measured indicators have been identified. The framework consists of five steps including compilation of an inventory of indicator; application of effectivity factors to rate indicators' effectiveness; estimation of effects; estimation of benefits for each ES; estimation of the total ES value of the ecosystem. The framework was applied to assess ecosystem services provided by trees, shrubs, herbs, birds, and bees, in green areas spanning an urban gradient in Gothenburg, Sweden. Estimates of perceived values of ecosystem services were obtained from interviews with the public and workshop activities with civil servants. The framework is systematic and transparent at all stages and appears to have potential utility in the existing spatial planning processes.
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| 3. |
- Braun, Sabine, et al.
(författare)
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Epidemiological analysis of ozone and nitrogen impacts on vegetation - Critical evaluation and recommendations
- 2017
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Ingår i: Science of the Total Environment. - : Elsevier BV. - 0048-9697 .- 1879-1026. ; 603-604, s. 785-792
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Tidskriftsartikel (refereegranskat)abstract
- © 2017 Elsevier B.V.For human health studies, epidemiology has been established as important tool to examine factors that affect the frequency and distribution of disease, injury, and other health-related events in a defined population, serving the purpose of establishing prevention and control programs. On the other hand, gradient studies have a long tradition in the research of air pollution effects on plants. While there is no principal difference between gradient and epidemiological studies, the former address more one-dimensional transects while the latter focus more on populations and include more experience in making quantitative predictions, in dealing with confounding factors and in taking into account the complex interplay of different factors acting at different levels. Epidemiological analyses may disentangle and quantify the contributions of different predictor variables to an overall effect, e.g. plant growth, and may generate hypotheses deserving further study in experiments. Therefore, their use in ecosystem research is encouraged. This article provides a number of recommendations on: (1) spatial and temporal aspects in preparing predictor maps of nitrogen deposition, ozone exposure and meteorological covariates; (2) extent of a dataset required for an analysis; (3) choice of the appropriate regression model and conditions to be satisfied by the data; (4) selection of the relevant explanatory variables; (5) treatment of interactions and confounding factors; and (6) assessment of model validity.
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| 4. |
- Broberg, Malin, 1989, et al.
(författare)
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CO2-induced changes in wheat grain composition: Meta-analysis and response functions
- 2017
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Ingår i: Agronomy. - : MDPI AG. - 2073-4395. ; 7:2
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Tidskriftsartikel (refereegranskat)abstract
- Elevated carbon dioxide (eCO2) stimulates wheat grain yield, but simultaneously reduces protein/nitrogen (N) concentration. Also, other essential nutrients are subject to change. This study is a synthesis of wheat experiments with eCO2, estimating the effects on N, minerals (B, Ca, Cd, Fe, K, Mg, Mn, Na, P, S, Zn), and starch. The analysis was performed by (i) deriving response functions to assess the gradual change in element concentration with increasing CO2 concentration, (ii) meta-analysis to test the average magnitude and significance of observed effects, and (iii) relating CO2 effects on minerals to effects on N and grain yield. Responses ranged from zero to strong negative effects of eCO2 on mineral concentration, with the largest reductions for the nutritionally important elements of N, Fe, S, Zn, and Mg. Together with the positive but small and non-significant effect on starch concentration, the large variation in effects suggests that CO2-induced responses cannot be explained only by a simple dilution model. To explain the observed pattern, uptake and transport mechanisms may have to be considered, along with the link of different elements to N uptake. Our study shows that eCO2 has a significant effect on wheat grain stoichiometry, with implications for human nutrition in a world of rising CO2.
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| 5. |
- Broberg, Malin, 1989, et al.
(författare)
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Effects of elevated CO2 on wheat yield: Non-linear response and relation to site productivity
- 2019
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Ingår i: Agronomy. - : MDPI AG. - 2073-4395. ; 9:5
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Tidskriftsartikel (refereegranskat)abstract
- © 2019 by the authors. Elevated carbon dioxide (eCO 2 ) is well known to stimulate plant photosynthesis and growth. Elevated carbon dioxide’s effects on crop yields are of particular interest due to concerns for future food security. We compiled experimental data where field-grown wheat (Triticum aestivum Linnaeus) was exposed to different CO 2 concentrations. Yield and yield components were analyzed by meta-analysis to estimate average effects, and response functions derived to assess effect size in relation to CO 2 concentration. Grain yield increased by 26% under eCO 2 (average ambient concentration of 372 ppm and elevated 605 ppm), mainly due to the increase in grain number. The response function for grain yield with CO 2 concentration strongly suggests a non-linear response, where yield stimulation levels off at ~600 ppm. This was supported by the meta-analysis, which did not indicate any significant difference in yield stimulation in wheat grown at 456–600 ppm compared to 601–750 ppm. Yield response to eCO 2 was independent of fumigation technique and rooting environment, but clearly related to site productivity, where relative CO 2 yield stimulation was stronger in low productive systems. The non-linear yield response, saturating at a relatively modest elevation of CO 2 , was of large importance for crop modelling and assessments of future food production under rising CO 2
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| 6. |
- Broberg, Malin, 1989, et al.
(författare)
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Fertilizer efficiency in wheat is reduced by ozone pollution
- 2017
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Ingår i: Science of the Total Environment. - : Elsevier BV. - 0048-9697 .- 1879-1026. ; 607-608, s. 876-880
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Tidskriftsartikel (refereegranskat)abstract
- Inefficient use of fertilizers by crops increases the risk of nutrient leaching from agro-ecosystems, resulting in economic loss and environmental contamination. We investigated how ground-level ozone affects the efficiency by which wheat used applied nitrogen (N) fertilizer to produce grain protein (NE P , N efficiency with respect to protein yield) and grain yield (NE Y , N efficiency with respect to grain yield) across a large number of open-top chamber field experiments. Our results show significant negative ozone effects on NE P and NE Y , both for a larger data set obtained from data mining (21 experiments, 70 treatments), and a subset of data for which stomatal ozone flux estimates were available (7 experiments, 22 treatments). For one experiment, we report new data on N content of different above-ground plant fractions as well as grain K and P content. Our analysis of the combined dataset demonstrates that the grain yield return for a certain investment in N fertilizer is reduced by ozone. Results from the experiment with more detailed data further show that translocation of accumulated N from straw and leaves to grains is significantly and negatively affected by ozone, and that ozone decreases fertilizer efficiency also for K and P. As a result of lower N fertilization efficiency, ozone causes a risk of increased N losses from agroecosystems, e.g. through nitrate leaching and nitrous oxide emissions, a hitherto neglected negative effect of ozone. This impact of ozone on the N cycle implies that society is facing a dilemma where it either (i) accepts increased N pollution and counteracts ozone-induced yield reductions by increasing fertilization or (ii) counteracts N pollution under elevated ozone by reducing fertilization, accepting further yield loss adding to the direct effect of ozone on yield.
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| 7. |
- Broberg, Malin, 1989, et al.
(författare)
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Ozone effects on wheat grain quality - A summary
- 2015
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Ingår i: Environmental Pollution. - : Elsevier BV. - 0269-7491. ; 197, s. 203-213
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Tidskriftsartikel (refereegranskat)abstract
- We synthesized the effects of ozone on wheat quality based on 42 experiments performed in Asia, Europe and North America. Data were analysed using meta-analysis and by deriving response functions between observed effects and daytime ozone concentration. There was a strong negative effect on 1000- grain weight and weaker but significant negative effects on starch concentration and volume weight. For protein and several nutritionally important minerals (K, Mg, Ca, P, Zn, Mn, Cu) concentration was significantly increased, but yields were significantly decreased by ozone. For other minerals (Fe, S, Na) effects were not significant or results inconclusive. The concentration and yield of potentially toxic Cd were negatively affected by ozone. Some baking properties (Zeleny value, Hagberg falling number) were positively influenced by ozone. Effects were similar in different exposure systems and for spring and winter wheat. Ozone effects on quality should be considered in future assessments of food security/ safety.
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| 8. |
- Coria, Jessica, 1979, et al.
(författare)
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Air pollution dynamics and the need for temporally differentiated road pricing
- 2015
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Ingår i: Transportation Research Part A: Policy and Practice. - : Elsevier BV. - 0965-8564. ; 75, s. 178-195
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Tidskriftsartikel (refereegranskat)abstract
- In this paper we investigate the effects of the temporal variation of pollution dispersion, traffic flows and vehicular emissions on pollution concentration and illustrate the need for temporally differentiated road pricing through an application to the case of the congestion charge in Stockholm, Sweden. By accounting explicitly for the role of pollution dispersion on optimal road pricing, we allow for a more comprehensive view of the economy– ecology interactions at stake, showing that price differentiation is an optimal response to the physical environment. Most congestion charges in place incorporate price bands to mitigate congestion. Our analysis indicates that, to ensure compliance with air quality standards, such price variations should also be a response to limited pollution dispersion.
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| 9. |
- Emberson, Lisa D., et al.
(författare)
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Ozone effects on crops and consideration in crop models
- 2018
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Ingår i: European Journal of Agronomy. - : Elsevier BV. - 1161-0301. ; 100:Special Issue: SI, s. 19-34
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Tidskriftsartikel (refereegranskat)abstract
- © 2018 The Authors We review current knowledge of the processes by which ozone will cause injury and damage to crop plants. We do this both through an understanding of the limitations to ozone uptake (i.e. ozone being transferred from some height in the atmosphere to the leaf boundary layer and subsequent uptake via the stomata) as well as through the internal plant processes that will result in the absorbed ozone dose causing damage and/or injury. We consider these processes across a range of scales by which ozone impacts plants, from cellular metabolism influencing leaf level physiology up to whole canopy and root system processes and feedbacks. We explore how these impacts affect leaf level photosynthesis and senescence (and associated carbon assimilation) as well as whole canopy resource acquisition (e.g. water and nutrients) and ultimately crop growth and yield. We consider these processes from the viewpoint of developing crop growth models capable of incorporating key ozone impact processes within modelling structures that assess crop growth under a variety of different abiotic stresses. These models would provide a dynamic assessment of the impact of ozone within the context of other key variables considered important in determining crop growth and yield. We consider the ability to achieve such modelling through an assessment of the different types of crop model currently available (e.g. empirical, radiation use efficiency, and photosynthesis based crop growth models). Finally, we show how international activities such as the AgMIP (Agricultural Modelling and Improvement Intercomparison Project) could see crop growth modellers collaborate to assess the capabilities of different crop models to simulate the effects of ozone and other stresses. The development of robust crop growth models capable of including ozone effects would substantially improve future national, regional and global risk assessments that aim to assess the role that ozone might play under future climatic conditions in limiting food supply.
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| 10. |
- Feng, Zhaozhong, et al.
(författare)
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A unifying explanation for variation in ozone sensitivity among woody plants
- 2018
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Ingår i: Global Change Biology. - : Wiley. - 1354-1013 .- 1365-2486. ; 24:1, s. 78-84
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Tidskriftsartikel (refereegranskat)abstract
- Tropospheric ozone is considered the most detrimental air pollutant for vegetation at the global scale, with negative consequences for both provisioning and climate regulating ecosystem services. In spite of recent developments in ozone exposure metrics, from a concentration-based to a more physiologically relevant stomatal flux-based index, large-scale ozone risk assessment is still complicated by a large and unexplained variation in ozone sensitivity among tree species. Here, we explored whether the variation in ozone sensitivity among woody species can be linked to interspecific variation in leaf morphology. We found that ozone tolerance at the leaf level was closely linked to leaf dry mass per unit leaf area (LMA) and that whole-tree biomass reductions were more strongly related to stomatal flux per unit leaf mass (r 2 =0.56) than to stomatal flux per unit leaf area (r 2 =0.42). Furthermore, the interspecific variation in slopes of ozone flux–response relationships was considerably lower when expressed on a leaf mass basis (coefficient of variation, CV=36%) than when expressed on a leaf area basis (CV=66%), and relationships for broadleaf and needle-leaf species converged when using the mass-based index. These results show that much of the variation in ozone sensitivity among woody plants can be explained by interspecific variation in LMA and that large-scale ozone impact assessment could be greatly improved by considering this well-known and easily measured leaf trait.
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