| 1. |
- Abbasi, Umar Aftab, et al.
(författare)
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Biological, structural and functional responses of tropical forests to environmental factors
- 2022
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Ingår i: Biological Conservation. - : Elsevier BV. - 0006-3207 .- 1873-2917. ; 276, s. 109792-109792
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Tidskriftsartikel (refereegranskat)abstract
- Here, we hypothesize that the biological, structural and functional attributes of tropical forests respond to water-related climatic and soil nutrient-related factors.Thus, we quantified 27 forest attributes and 20 environmental factors across 189 plots of Sri Lankan tropical forests. Our results suggest that environmental conditions were characterized by both water-related and temperature-related factors, and as such, both coarse-textured and compacted-structured soils determined soil conditions.Forest conditions were characterized by high species-functional diversity, structural complexity and aboveground biomass-related functions. We found strong positive effects of water-related climatic factors followed by temperature-related climatic factors but negligible positive to negative effects of textured-related and nutrient-related soil factors on most of the biological, structural and functional attributes.Overall the biodiversity and carbon stocks of Sri Lankan tropical forests are likely to increase with water-energy balance and improved soil conditions, and thus, studied forests could offset a substantial quantity of anthropogenic carbon emissions to achieve carbon neutrality which can have both regional and global significance if protected from anthropogenic disturbances.
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| 2. |
- Abbasi, Umar Aftab, et al.
(författare)
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Species α-diversity promotes but β-diversity restricts aboveground biomass in tropical forests, depending on stand structure and environmental factors
- 2022
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Ingår i: Journal of Forestry Research. - Göteborg : IVL Svenska Miljöinstitutet AB. - 1007-662X .- 1993-0607.
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Tidskriftsartikel (refereegranskat)abstract
- Forest plays a vital role in the global biogeochemical cycles through a high rate of carbon sequestration and harboring biodiversity. However, local species diversity is declining while also becoming increasingly homogenized across communities. Although effects of local biotic processes (e.g., species α-diversity and stand structural heterogeneity) and environmental factors on aboveground biomass (AGB) have been widely tested, there is a huge knowledge gap for the effect of regional biotic processes (i.e., taxonomic and functional β-diversity) in forests. Here, we hypothesized that regional and local environmental factors along with biotic processes jointly regulate AGB through species shifts in tropical forests.Using piecewise structural equation modeling (pSEM), we linked climatic water availability, soil fertility, stand structural heterogeneity (either tree DBH inequality, height inequality, or stand density), species α-diversity, taxonomic or functional β-diversity (and its two components; β-turnover and β-richness), and AGB across 189 inventory plots in tropical forests of Sri Lanka. Soil fertility and climatic water availability shaped local and regional biotic processes. Stand structural heterogeneity promoted species α-diversity but declined β-diversity (but increased β-taxonomic turnover). Species α-diversity and stand structural heterogeneity promoted AGB whereas taxonomic and functional β-diversity declined (but β-taxonomic turnover increased) AGB.The relationships of AGB with species α-diversity and β-diversity varied from significant to nonsignificant positive depending on the specific combinations of stand structural heterogeneity metrics used. This study shows that local biotic processes could increase AGB due to the local and regional niche complementarity effect whereas the regional biotic processes could restrict AGB due to the regional selection or functional redundancy effect under favorable environmental conditions. We argue that biotic homogenization, as well as drought conditions, may have strong divergent impacts on forest functions and that the impacts of tree diversity loss may greatly reduce carbon sequestration.
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| 3. |
- Aggarwal, Rahul, 1994, et al.
(författare)
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Influence of data selection on aquatic ecotoxicity characterization factors for selected persistent and mobile substances
- 2024
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Ingår i: International Journal of Life Cycle Assessment. - Göteborg : IVL Svenska Miljöinstitutet AB. - 1614-7502 .- 0948-3349. ; 29:2, s. 344-354
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Tidskriftsartikel (refereegranskat)abstract
- Purpose: This paper addresses the lack of ecotoxicity characterization factors (CFs) for persistent and mobile (PM) chemicals in life cycle assessment. The specific aims are (1) to provide CFs for 64 selected chemicals and benchmark them against the USEtox database, (2) to propose an ecotoxicity data harmonization strategy, and (3) to analyze the influence of ecotoxicity data sources and data harmonization strategies. Methods: Sixty-four per- and polyfluoroalkyl substances (PFAS), triazines, and triazoles were selected. An ecotoxicity data harmonization strategy was developed to ensure data consistency. A screening strategy for including transformation products was also developed. Existing CFs in the USEtox organic substances database (version 2.01) were identified, and new CFs were calculated based on available data sources. The USEtox model (version 2.13) was used for calculations, and the collected ecotoxicity data from different sources were varied to test their influence. Results and discussion: The ecotoxicity data harmonization strategy excluded a considerable amount of incompatible data. To the list of 64 chemicals, 3 transformation products were added. Out of the 67 chemicals, experimental ecotoxicity data were available for 47, leading to the use of in silico tools and average values to fill data gaps for 20 chemicals. CFs for 67 chemicals could thus be provided. Comparing CFs calculated based on experimental and estimated ecotoxicity data reveals that the estimated data leads to considerably different CF values. Conclusions: The paper provides strategies for ecotoxicity data harmonization and the inclusion of transformation products. The limited availability of experimental ecotoxicity data and differing results of the applied estimation methods highlight the need for further development of estimation methods. In addition, further development in including transformation products is recommended, which is particularly relevant for PM chemicals.
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| 4. |
- Ahlgren, Erik, 1962, et al.
(författare)
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Transport biofuels in global energy–economy modelling – a review of comprehensive energy systems assessment approaches
- 2017
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Ingår i: GCB Bioenergy. - : Wiley. - 1757-1707 .- 1757-1693. ; 9, s. 1168–1180-
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Forskningsöversikt (refereegranskat)abstract
- The high oil dependence and the growth of energy use in the transport sector have increased the interest in alternative nonfossil fuels as a measure to mitigate climate change and improve energy security. More ambitious energy and environmental targets and larger use of nonfossil energy in the transport sector increase energy–transport interactions and system effects over sector boundaries. While the stationary energy sector (e.g., electricity and heat generation) and the transport sector earlier to large degree could be considered as separate systems with limited interaction, integrated analysis approaches and assessments of energy–transport interactions now grow in importance. In recent years, the scientific literature has presented an increasing number of global energy–economy future studies based on systems modelling treating the transport sector as an integral part of the overall energy system and/or economy. Many of these studies provide important insights regarding transport biofuels. To clarify similarities and differences in approaches and results, the present work reviews studies on transport biofuels in global energy–economy modelling and investigates what future role comprehensive global energy–economy modelling studies portray for transport biofuels in terms of their potential and competitiveness. The results vary widely between the studies, but the resulting transport biofuel market shares are mainly below 40% during the entire time periods analysed. Some of the reviewed studies show higher transport biofuel market shares in the medium (15–30 years) than in the long term (above 30 years), and, in the long-term models, at the end of the modelling horizon, transport biofuels are often substituted by electric and hydrogen cars.
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| 5. |
- Ahumada, Sofía, et al.
(författare)
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Calibration of SO2 and NO2 Electrochemical Sensors via a Training and Testing Method in an Industrial Coastal Environment
- 2022
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Ingår i: Sensors. - : IVL Svenska Miljöinstitutet. - 1424-8220. ; 22:19, s. 7281-7281
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Tidskriftsartikel (refereegranskat)abstract
- Low-cost sensors can provide inaccurate data as temperature and humidity affect sensoraccuracy. Therefore, calibration and data correction are essential to obtain reliable measurements.This article presents a training and testing method used to calibrate a sensor module assembledfrom SO2 and NO2 electrochemical sensors (Alphasense B4 and B43F) alongside air temperature (T)and humidity (RH) sensors.Field training and testing were conducted in the industrialized coastalarea of Quintero Bay, Chile. The raw responses of the electrochemical (mV) and T-RH sensors weresubjected to multiple linear regression (MLR) using three data segments, based on either voltage(SO2 sensor) or temperature (NO2). The resulting MLR equations were used to estimate the referenceconcentration. In the field test, calibration improved the performance of the sensors after addingT and RH in a linear model.The most robust models for NO2 were associated with data collectedat T < 10 C (R2 = 0.85), while SO2 robust models (R2 = 0.97) were associated with data segmentscontaining higher voltages. Overall, this training and testing method reduced the bias due to T andHR in the evaluated sensors and could be replicated in similar environments to correct raw data fromlow-cost electrochemical sensors. A calibration method based on training and sensor testing afterrelocation is presented. The results show that the SO2 sensor performed better when modeled fordifferent segments of voltage data, and the NO2 sensor model performed better when calibrated fordifferent temperature data segments.
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| 6. |
- Akselsson, Cecilia, et al.
(författare)
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A Combined Measurement and Modelling Approach to Assess the Sustainability of Whole-Tree Harvesting—A Swedish Case Study
- 2021
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Ingår i: Sustainability. - : MDPI AG. - 2071-1050. ; 13:4
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Tidskriftsartikel (refereegranskat)abstract
- The demand of renewable energy has increased the interest in whole-tree harvesting. The sustainability of whole-tree harvesting after clear-cutting, from an acidification point of view, depends on two factors: the present acidification status and the further loss of buffering capacity at harvesting. The aims of this study were to investigate the relationship between these two factors at 26 sites along an acidification gradient in Sweden, to divide the sites into risk classes, and to examine the geographical distribution of them in order to provide policy-relevant insights. The present status was represented by the acid neutralizing capacity (ANC) in soil solution, and the loss of buffering capacity was represented by the estimated exceedance of critical biomass harvesting (CBH). The sites were divided into three risk classes combining ANC and exceedance of CBH. ANC and exceedance of CBH were negatively correlated, and most sites had either ANC < 0 and exceedance (high risk) or ANC > 0 and no exceedance (low risk). There was a geographical pattern, with the high risk class concentrated to southern Sweden, which was mainly explained by higher historical sulfur deposition and site productivity in the south. The risk classes can be used in the formulation of policies on whole-tree harvesting and wood ash recycling.
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| 7. |
- Alfredsson, Eva C., et al.
(författare)
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Industrial climate mitigation strategies and the remaining fair carbon budget – The case of Sweden
- 2024
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Ingår i: Next Sustainability. - 2949-8236. ; 3, s. 100031-100031
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Tidskriftsartikel (refereegranskat)abstract
- This article explores the climate mitigation strategies of the 15 industries with the largest carbon dioxide emissions in Sweden. Starting from two carbon budget alternatives, we analyse the mitigation projections of the companies in relation to what can be considered their fair share of the remaining carbon budget for Sweden.We furthermore determine the uncertainties associated with the strategies. The results suggest that if the communicated mitigation plans are implemented as planned, the companies overdraft our main, 1.5-degree, budget option but stay within the alternative 1.7-degree budget. The analysis shows, however, that the timing and efficiency of emission reductions are crucial.Already small delays or lower efficiency in implementation, result in evident overdrafts of also the alternative budget. There are also substantial political and technical risks which can prevent timely mitigations. The article makes a novel contribution by analyzing industries’ mitigation strategies relative to their share of the remaining carbon budget.The article demonstrates the importance of transparent industrial climate mitigation strategies and in particular the need for policymakers to set incentive structures to promote strategy implementation.
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| 8. |
- Ali, Arshad, et al.
(författare)
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Big-sized trees and species-functional diversity pathways mediate divergent impacts of environmental factors on individual biomass variability in Sri Lankan tropical forests
- 2022
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Ingår i: Journal of Environmental Management. - : Elsevier BV. - 0301-4797 .- 1095-8630. ; 315, s. 115177-115177
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Tidskriftsartikel (refereegranskat)abstract
- In this study, we used the Partial Least Squares Structural Equation Models (PLS-SEMs), and other complementary analyses, on data from 189 tropical forest plots in Sri Lanka, to test the linkages amongst climate, soil, plot conditions, big-sized trees, species-functional diversity, and abiotic and biotic effects on individual biomass variability (BioVar). This study suggests that individual tree biomass variability (i.e., BioVar) should be considered for managing natural tropical forests in the context of the plant-plant interactions for species coexistence.
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| 9. |
- Almasi, Alexandra, et al.
(författare)
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Kartläggning av plastflöden i Stockholm
- 2020
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Rapport (refereegranskat)abstract
- Rapporten presenterar plastflöden i Stockholms stad, både från kommunens verksamheter och från alla invånare, från inköp till avfallshantering. Resultaten från kartläggningen ska användas av Stockholms stad som underlag för att ta fram en handlingsplan för minskad plastanvändning och underlätta prioritering och utformning av åtgärder för att minska onödig plastanvändning och klimatpåverkan från plast, öka materialåtervinningen av plastavfall och minska spridningen av plastskräp.
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| 10. |
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