| 1. |
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| 2. |
- Hudson, Lawrence N, et al.
(författare)
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The database of the PREDICTS (Projecting Responses of Ecological Diversity In Changing Terrestrial Systems) project
- 2017
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Ingår i: Ecology and Evolution. - : John Wiley & Sons. - 2045-7758. ; 7:1, s. 145-188
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Tidskriftsartikel (refereegranskat)abstract
- The PREDICTS project-Projecting Responses of Ecological Diversity In Changing Terrestrial Systems (www.predicts.org.uk)-has collated from published studies a large, reasonably representative database of comparable samples of biodiversity from multiple sites that differ in the nature or intensity of human impacts relating to land use. We have used this evidence base to develop global and regional statistical models of how local biodiversity responds to these measures. We describe and make freely available this 2016 release of the database, containing more than 3.2 million records sampled at over 26,000 locations and representing over 47,000 species. We outline how the database can help in answering a range of questions in ecology and conservation biology. To our knowledge, this is the largest and most geographically and taxonomically representative database of spatial comparisons of biodiversity that has been collated to date; it will be useful to researchers and international efforts wishing to model and understand the global status of biodiversity.
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| 3. |
- Abdallah, J., et al.
(författare)
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The optical instrumentation of the ATLAS Tile Calorimeter
- 2013
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Ingår i: Journal of Instrumentation. - 1748-0221. ; 8, s. P01005-
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Tidskriftsartikel (refereegranskat)abstract
- The Tile Calorimeter, covering the central region of the ATLAS experiment up to pseudorapidities of +/-1.7, is a sampling device built with scintillating tiles that alternate with iron plates. The light is collected in wave-length shifting (WLS) fibers and is read out with photomultipliers. In the characteristic geometry of this calorimeter the tiles lie in planes perpendicular to the beams, resulting in a very simple and modular mechanical and optical layout. This paper focuses on the procedures applied in the optical instrumentation of the calorimeter, which involved the assembly of about 460,000 scintillator tiles and 550,000 WLS fibers. The outcome is a hadronic calorimeter that meets the ATLAS performance requirements, as shown in this paper.
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| 4. |
- Abdallah, J., et al.
(författare)
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Mechanical construction and installation of the ATLAS tile calorimeter
- 2013
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Ingår i: Journal of Instrumentation. - 1748-0221. ; 8, s. T11001-
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Tidskriftsartikel (refereegranskat)abstract
- This paper summarises the mechanical construction and installation of the Tile Calorimeter for the ATLAS experiment at the Large Hadron Collider in CERN, Switzerland. The Tile Calorimeter is a sampling calorimeter using scintillator as the sensitive detector and steel as the absorber and covers the central region of the ATLAS experiment up to pseudorapidities +/- 1.7. The mechanical construction of the Tile Calorimeter occurred over a period of about 10 years beginning in 1995 with the completion of the Technical Design Report and ending in 2006 with the installation of the final module in the ATLAS cavern. During this period approximately 2600 metric tons of steel were transformed into a laminated structure to form the absorber of the sampling calorimeter. Following instrumentation and testing, which is described elsewhere, the modules were installed in the ATLAS cavern with a remarkable accuracy for a structure of this size and weight.
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| 5. |
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| 6. |
- Hudson, Lawrence N., et al.
(författare)
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The PREDICTS database : a global database of how local terrestrial biodiversity responds to human impacts
- 2014
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Ingår i: Ecology and Evolution. - : Wiley. - 2045-7758. ; 4:24, s. 4701-4735
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Tidskriftsartikel (refereegranskat)abstract
- Biodiversity continues to decline in the face of increasing anthropogenic pressures such as habitat destruction, exploitation, pollution and introduction of alien species. Existing global databases of species' threat status or population time series are dominated by charismatic species. The collation of datasets with broad taxonomic and biogeographic extents, and that support computation of a range of biodiversity indicators, is necessary to enable better understanding of historical declines and to project - and avert - future declines. We describe and assess a new database of more than 1.6 million samples from 78 countries representing over 28,000 species, collated from existing spatial comparisons of local-scale biodiversity exposed to different intensities and types of anthropogenic pressures, from terrestrial sites around the world. The database contains measurements taken in 208 (of 814) ecoregions, 13 (of 14) biomes, 25 (of 35) biodiversity hotspots and 16 (of 17) megadiverse countries. The database contains more than 1% of the total number of all species described, and more than 1% of the described species within many taxonomic groups - including flowering plants, gymnosperms, birds, mammals, reptiles, amphibians, beetles, lepidopterans and hymenopterans. The dataset, which is still being added to, is therefore already considerably larger and more representative than those used by previous quantitative models of biodiversity trends and responses. The database is being assembled as part of the PREDICTS project (Projecting Responses of Ecological Diversity In Changing Terrestrial Systems - ). We make site-level summary data available alongside this article. The full database will be publicly available in 2015.
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| 7. |
- Osorio, A., et al.
(författare)
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Evaluation of the XRCC1 gene as a phenotypic modifier in BRCA1/2 mutation carriers. Results from the consortium of investigators of modifiers of BRCA1/BRCA2
- 2011
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Ingår i: British Journal of Cancer. - : Springer Science and Business Media LLC. - 1532-1827 .- 0007-0920. ; 104:8, s. 1356-1361
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Single-nucleotide polymorphisms (SNPs) in genes involved in DNA repair are good candidates to be tested as phenotypic modifiers for carriers of mutations in the high-risk susceptibility genes BRCA1 and BRCA2. The base excision repair (BER) pathway could be particularly interesting given the relation of synthetic lethality that exists between one of the components of the pathway, PARP1, and both BRCA1 and BRCA2. In this study, we have evaluated the XRCC1 gene that participates in the BER pathway, as phenotypic modifier of BRCA1 and BRCA2. METHODS: Three common SNPs in the gene, c.-77C>T (rs3213245) p.Arg280His (rs25489) and p.Gln399Arg (rs25487) were analysed in a series of 701 BRCA1 and 576 BRCA2 mutation carriers. RESULTS: An association was observed between p.Arg280His-rs25489 and breast cancer risk for BRCA2 mutation carriers, with rare homozygotes at increased risk relative to common homozygotes (hazard ratio: 22.3, 95% confidence interval: 14.3-34, P<0.001). This association was further tested in a second series of 4480 BRCA1 and 3016 BRCA2 mutation carriers from the Consortium of Investigators of Modifiers of BRCA1 and BRCA2. CONCLUSIONS AND INTERPRETATION: No evidence of association was found when the larger series was analysed which lead us to conclude that none of the three SNPs are significant modifiers of breast cancer risk for mutation carriers. British Journal of Cancer (2011) 104, 1356-1361. doi:10.1038/bjc.2011.91 www.bjcancer.com Published online 22 March 2011 (C) 2011 Cancer Research UK
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| 8. |
- Soranno, Patricia A., et al.
(författare)
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LAGOS-NE : A multi-scaled geospatial and temporal database of lake ecological context and water quality for thousands of U.S. lakes
- 2017
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Ingår i: GigaScience. - : Oxford University Press (OUP). - 2047-217X. ; 6:12, s. 1-22
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Tidskriftsartikel (refereegranskat)abstract
- Understanding the factors that affect water quality and the ecological services provided by freshwater ecosystems is an urgent global environmental issue. Predicting how water quality will respond to global changes not only requires water quality data, but also information about the ecological context of individual water bodies across broad spatial extents. Because lake water quality is usually sampled in limited geographic regions, often for limited time periods, assessing the environmental controls of water quality requires compilation of many data sets across broad regions and across time into an integrated database. LAGOS-NE accomplishes this goal for lakes in the northeastern-most 17 US states. LAGOS-NE contains data for 51101 lakes and reservoirs larger than 4 ha in 17 lake-rich US states. The database includes 3 datamodules for: lake location and physical characteristics for all lakes; ecological context (i.e., the land use, geologic, climatic, and hydrologic setting of lakes) for all lakes; and in situmeasurements of lake water quality for a subset of the lakes fromthe past 3 decades for approximately 2600–12 000 lakes depending on the variable. The database contains approximately 150000 measures of total phosphorus, 200 000 measures of chlorophyll, and 900 000 measures of Secchi depth. The water quality data were compiled from87 lake water quality data sets fromfederal, state, tribal, and non-profit agencies, university researchers, and citizen scientists. This database is one of the largest andmost comprehensive databases of its type because it includes both in situmeasurements and ecological context data. Because ecological context can be used to study a variety of other questions about lakes, streams, and wetlands, this database can also be used as the foundation for other studies of freshwaters at broad spatial and ecological scales
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| 9. |
- Downing, Andrea S., et al.
(författare)
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Coupled human and natural system dynamics as key to the sustainability of Lake Victoria's ecosystem services
- 2014
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Ingår i: Ecology and Society. - 1708-3087. ; 19:4, s. 31-
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Tidskriftsartikel (refereegranskat)abstract
- East Africa's Lake Victoria provides resources and services to millions of people on the lake's shores and abroad. In particular, the lake's fisheries are an important source of protein, employment, and international economic connections for the whole region. Nonetheless, stock dynamics are poorly understood and currently unpredictable. Furthermore, fishery dynamics are intricately connected to other supporting services of the lake as well as to lakeshore societies and economies. Much research has been carried out piecemeal on different aspects of Lake Victoria's system; e.g., societies, biodiversity, fisheries, and eutrophication. However, to disentangle drivers and dynamics of change in this complex system, we need to put these pieces together and analyze the system as a whole. We did so by first building a qualitative model of the lake's social-ecological system. We then investigated the model system through a qualitative loop analysis, and finally examined effects of changes on the system state and structure. The model and its contextual analysis allowed us to investigate system-wide chain reactions resulting from disturbances. Importantly, we built a tool that can be used to analyze the cascading effects of management options and establish the requirements for their success. We found that high connectedness of the system at the exploitation level, through fisheries having multiple target stocks, can increase the stocks' vulnerability to exploitation but reduce society's vulnerability to variability in individual stocks. We describe how there are multiple pathways to any change in the system, which makes it difficult to identify the root cause of changes but also broadens the management toolkit. Also, we illustrate how nutrient enrichment is not a self-regulating process, and that explicit management is necessary to halt or reverse eutrophication. This model is simple and usable to assess system-wide effects of management policies, and can serve as a paving stone for future quantitative analyses of system dynamics at local scales.
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| 10. |
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| 11. |
- Mooij, Wolf M., et al.
(författare)
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Modeling water quality in the Anthropocene : directions for the next-generation aquatic ecosystem models
- 2019
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Ingår i: Current Opinion in Environmental Sustainability. - : Elsevier BV. - 1877-3435 .- 1877-3443. ; 36, s. 85-95
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Forskningsöversikt (refereegranskat)abstract
- Everything changes and nothing stands still (Heraclitus). Here we review three major improvements to freshwater aquatic ecosystem models - and ecological models in general - as water quality scenario analysis tools towards a sustainable future. To tackle the rapid and deeply connected dynamics characteristic of the Anthropocene, we argue for the inclusion of eco-evolutionary, novel ecosystem and social-ecological dynamics. These dynamics arise from adaptive responses in organisms and ecosystems to global environmental change and act at different integration levels and different time scales. We provide reasons and means to incorporate each improvement into aquatic ecosystem models. Throughout this study we refer to Lake Victoria as a microcosm of the evolving novel social-ecological systems of the Anthropocene. The Lake Victoria case clearly shows how interlinked eco-evolutionary, novel ecosystem and social-ecological dynamics are, and demonstrates the need for transdisciplinary research approaches towards global sustainability.
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| 12. |
- Tranvik, Lars J., et al.
(författare)
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Lakes and reservoirs as regulators of carbon cycling and climate
- 2009
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Ingår i: Limnology and Oceanography. - : Wiley. - 0024-3590 .- 1939-5590. ; 54:6:2, s. 2298-2314
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Forskningsöversikt (refereegranskat)abstract
- We explore the role of lakes in carbon cycling and global climate, examine the mechanisms influencing carbon pools and transformations in lakes, and discuss how the metabolism of carbon in the inland waters is likely to change in response to climate. Furthermore, we project changes as global climate change in the abundance and spatial distribution of lakes in the biosphere, and we revise the estimate for the global extent of carbon transformation in inland waters. This synthesis demonstrates that the global annual emissions of carbon dioxide from inland waters to the atmosphere are similar in magnitude to the carbon dioxide uptake by the oceans and that the global burial of organic carbon in inland water sediments exceeds organic carbon sequestration on the ocean floor. The role of inland waters in global carbon cycling and climate forcing may be changed by human activities, including construction of impoundments, which accumulate large amounts of carbon in sediments and emit large amounts of methane to the atmosphere. Methane emissions are also expected from lakes on melting permafrost. The synthesis presented here indicates that (1) inland waters constitute a significant component of the global carbon cycle, (2) their contribution to this cycle has significantly changed as a result of human activities, and (3) they will continue to change in response to future climate change causing decreased as well as increased abundance of lakes as well as increases in the number of aquatic impoundments.
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| 13. |
- Dade, M. C., et al.
(författare)
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Inequalities in the adaptive cycle : reorganizing after disasters in an unequal world
- 2022
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Ingår i: Ecology and Society. - 1708-3087. ; 27:4
-
Tidskriftsartikel (refereegranskat)abstract
- Natural hazards can trigger disasters that lead to the collapse and reorganization of social-ecological systems. This reorganization can involve systems transitioning to more positive trajectories. The Panarchy framework, which conceptualizes social-ecological systems as dynamic interrelated adaptive cycles, is a common conceptual framework for understanding system reorganization. However, it is unclear how inequalities, social mechanisms known to influence disaster recovery outcomes, shape a system's adaptive cycle post-disaster. Understanding the roles of inequalities can help develop social-ecological models to identify processes that build resilience into disaster recovery. We applied the Panarchy framework to inform propositions describing how inequalities can influence the reorganization of social-ecological systems after disasters triggered by natural hazards. We qualitatively analyzed a selection of case studies that discussed inequalities pre-and post-disasters and related these to adaptive-cycle system characteristics (i.e., potential, connectedness, and resilience). We identified three propositions: 1) The ability of groups to reorganize after a disaster varies across the inequality spectrum; 2) The reorganizing abilities of groups across the inequality spectrum impact one another; and 3) The presence of inequalities affect connectedness within the system. Incorporating these propositions into social-ecological system modeling can improve our understanding of how inequalities impact system reorganization. This information can support disaster recovery plans that strengthen a system's ability to enter a more positive trajectory post-disaster.
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| 14. |
- De Palma, Adriana, et al.
(författare)
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Predicting bee community responses to land-use changes : effects of geographic and taxonomic biases
- 2016
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Ingår i: Scientific Reports. - : Nature Publishing Group. - 2045-2322. ; 6, s. 1-14
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Tidskriftsartikel (refereegranskat)abstract
- Land-use change and intensification threaten bee populations worldwide, imperilling pollination services. Global models are needed to better characterise, project, and mitigate bees' responses to these human impacts. The available data are, however, geographically and taxonomically unrepresentative; most data are from North America and Western Europe, overrepresenting bumblebees and raising concerns that model results may not be generalizable to other regions and taxa. To assess whether the geographic and taxonomic biases of data could undermine effectiveness of models for conservation policy, we have collated from the published literature a global dataset of bee diversity at sites facing land-use change and intensification, and assess whether bee responses to these pressures vary across 11 regions (Western, Northern, Eastern and Southern Europe; North, Central and South America; Australia and New Zealand; South East Asia; Middle and Southern Africa) and between bumblebees and other bees. Our analyses highlight strong regionally-based responses of total abundance, species richness and Simpson's diversity to land use, caused by variation in the sensitivity of species and potentially in the nature of threats. These results suggest that global extrapolation of models based on geographically and taxonomically restricted data may underestimate the true uncertainty, increasing the risk of ecological surprises.
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| 15. |
- Downing, J. A., et al.
(författare)
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Global abundance and size distribution of streams and rivers
- 2012
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Ingår i: Inland Waters. - 2044-2041 .- 2044-205X. ; 2:4, s. 229-236
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Tidskriftsartikel (refereegranskat)abstract
- To better integrate lotic ecosystems into global cycles and budgets, we provide approximations of the size-distribution and areal extent of streams and rivers. One approach we used was to employ stream network theory combined with data on stream width. We also used detailed stream networks on 2 continents to estimate the fraction of continental area occupied by streams worldwide and corrected remote sensing stream inventories for unresolved small streams. Our estimates of global fluvial area are 485 000 to 662 000 km2 and are +30–300% of published appraisals. Moderately sized rivers (orders 5–9) seem to comprise the greatest global area, with less area covered by low and high order streams, while global stream length, and therefore the riparian interface, is dominated by 1st order streams. Rivers and streams are likely to cover 0.30–0.56% of the land surface and make contributions to global processes and greenhouse gas emissions that may be +20–200% greater than those implied by previous estimates.
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| 16. |
- Downing, J. A., et al.
(författare)
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The global abundance and size distribution of lakes, ponds, and impoundments
- 2006
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Ingår i: Limnology and Oceanography. - 0024-3590 .- 1939-5590. ; 51:5, s. 2388-2397
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Tidskriftsartikel (refereegranskat)abstract
- One of the major impediments to the integration of lentic ecosystems into global environmental analyses has been fragmentary data on the extent and size distribution of lakes, ponds, and impoundments. We use new data sources, enhanced spatial resolution, and new analytical approaches to provide new estimates of the global abundance of surface-water bodies. A global model based on the Pareto distribution shows that the global extent of natural lakes is twice as large as previously known (304 million lakes; 4.2 million km(2) in area) and is dominated in area by millions of water bodies smaller than 1 km(2). Similar analyses of impoundments based on inventories of large, engineered dams show that impounded waters cover approximately 0.26 million km(2). However, construction of low-tech farm impoundments is estimated to be between 0.1% and 6% of farm area worldwide, dependent upon precipitation, and represents > 77,000 km(2) globally, at present. Overall, about 4.6 million km(2) of the earth's continental "land" surface (> 3%) is covered by water. These analyses underscore the importance of explicitly considering lakes, ponds, and impoundments, especially small ones, in global analyses of rates and processes.
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| 17. |
- Hesketh, Kylie D., et al.
(författare)
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Protocol for the Lets Grow randomised controlled trial : examining efficacy, cost-effectiveness and scalability of a m-Health intervention for movement behaviours in toddlers
- 2022
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Ingår i: BMJ Open. - : BMJ Publishing Group. - 2044-6055. ; 12:3
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Tidskriftsartikel (refereegranskat)abstract
- Introduction Despite being an important period for the development of movement behaviours (physical activity, sedentary behaviour and sleep), few interventions commencing prior to preschool have been trialled. The primary aim of this trial is to assess the 12-month efficacy of the Lets Grow mHealth intervention, designed to improve the composition of movement behaviours in children from 2 years of age. Lets Grow is novel in considering composition of movement behaviours as the primary outcome, using non-linear dynamical approaches for intervention delivery, and incorporating planning for real-world implementation and scale-up from its inception. Methods and analysis A randomised controlled trial will test the effects of the 12-month parental support mHealth intervention, Lets Grow, compared with a control group that will receive usual care plus electronic newsletters on unrelated topics for cohort retention. Lets Grow will be delivered via a purpose-designed mobile web application with linked SMS notifications. Intervention content includes general and movement-behaviour specific parenting advice and incorporates established behaviour change techniques. Intervention adherence will be monitored by app usage data. Data will be collected from participants using 24-hour monitoring of movement behaviours and parent report at baseline (T-0), mid-intervention (T-1; 6 months post baseline), at intervention conclusion (T-2; 12 months post baseline) and 1-year post intervention (T-3; 2 years post baseline). The trial aims to recruit 1100 families from across Australia during 2021. In addition to assessment of efficacy, an economic evaluation and prospective scalability evaluation will be conducted. Ethics and dissemination The study was approved by the Deakin University Human Ethics Committee (2020-077). Study findings will be disseminated through publication in peer-reviewed journals, presentation at scientific and professional conferences, and via social and traditional media.
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| 18. |
- Mooij, Wolf M., et al.
(författare)
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Serving many at once : How a database approach can create unity in dynamical ecosystem modelling
- 2014
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Ingår i: Environmental Modelling & Software. - : Elsevier BV. - 1364-8152 .- 1873-6726. ; 61, s. 266-273
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Tidskriftsartikel (refereegranskat)abstract
- Simulation modelling in ecology is a field that is becoming increasingly compartmentalized. Here we propose a Database Approach To Modelling (DATM) to create unity in dynamical ecosystem modelling with differential equations. In this approach the storage of ecological knowledge is independent of the language and platform in which the model will be run. To create an instance of the model, the information in the database is translated and augmented with the language and platform specifics. This process is automated so that a new instance can be created each time the database is updated. We describe the approach using the simple Lotka-Volterra model and the complex ecosystem model for shallow lakes PCLake, which we automatically implement in the frameworks OSIRIS, GRIND for MATLAB, ACSL, R, DUFLOW and DELWAQ. A clear advantage of working in a database is the overview it provides. The simplicity of the approach only adds to its elegance.
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| 19. |
- van Gerven, Luuk P. A., et al.
(författare)
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Advantages of concurrent use of multiple software frameworks in water quality modelling using a database approach
- 2015
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Ingår i: Fundamental and Applied Limnology. - : Schweizerbart. - 1863-9135. ; 186:1-2, s. 5-20
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Tidskriftsartikel (refereegranskat)abstract
- Water quality modelling deals with multidisciplinary questions ranging from fundamental to applied. Addressing this broad range of questions requires multiple analysis techniques and therefore multiple frameworks. Through the recently developed database approach to modelling (DATM), it has become possible to run a model in multiple software frameworks without much overhead. Here we apply DATM to the ecosystem model for ditches PCDitch and its twin model for shallow lakes PCLake. Using DATM, we run these models in six frameworks (ACSL, DELWAQ, DUFLOW, GRIND for MATLAB, OSIRIS and R), and report on the possible model analyses with tools provided by each framework. We conclude that the dynamic link between frameworks and models resulting from DATM has the following main advantages: it allows one to use the framework one is familiar with for most model analyses and eases switching between frameworks for complementary model analyses, including the switch between a 0-D and 1-D to 3-D setting. Moreover, the strength of each framework - including runtime performance - can now be easily exploited. We envision that a community-based further development of the concept can contribute to the future development of water quality modelling, not only by addressing multidisciplinary questions but also by facilitating the exchange of models and process formulations within the community of water quality modellers.
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| 20. |
- Aquila, A., et al.
(författare)
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The linac coherent light source single particle imaging road map
- 2015
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Ingår i: Structural Dynamics. - : AIP Publishing. - 2329-7778. ; 2:4
-
Tidskriftsartikel (refereegranskat)abstract
- Intense femtosecond x-ray pulses from free-electron laser sources allow the imag-ing of individual particles in a single shot. Early experiments at the Linac CoherentLight Source (LCLS) have led to rapid progress in the field and, so far, coherentdiffractive images have been recorded from biological specimens, aerosols, andquantum systems with a few-tens-of-nanometers resolution. In March 2014, LCLSheld a workshop to discuss the scientific and technical challenges for reaching theultimate goal of atomic resolution with single-shot coherent diffractive imaging. This paper summarizes the workshop findings and presents the roadmap towardreaching atomic resolution, 3D imaging at free-electron laser sources.
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| 21. |
- Bastviken, David, et al.
(författare)
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Freshwater Methane Emissions Offset the Continental Carbon Sink
- 2011
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Ingår i: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 331:6013, s. 50-50
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Tidskriftsartikel (refereegranskat)abstract
- Inland waters (lakes, reservoirs, streams, and rivers) are often substantial methane (CH4) sources in the terrestrial landscape. They are, however, not yet well integrated in global greenhouse gas (GHG) budgets. Data from 474 freshwater ecosystems and the most recent global water area estimates indicate that freshwaters emit at least 103 teragrams of CH4 year−1, corresponding to 0.65 petagrams of C as carbon dioxide (CO2) equivalents year−1, offsetting 25% of the estimated land carbon sink. Thus, the continental GHG sink may be considerably overestimated, and freshwaters need to be recognized as important in the global carbon cycle.
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| 22. |
- Beers, Keith M., et al.
(författare)
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Absence of Schroeder's Paradox in a Nanostructured Block Copolymer Electrolyte Membrane
- 2014
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Ingår i: The Journal of Physical Chemistry Part B. - : American Chemical Society (ACS). - 1520-5207 .- 1520-6106. ; 118:24, s. 6785-6791
-
Tidskriftsartikel (refereegranskat)abstract
- This is a study of morphology, water uptake, and proton conductivity of a sulfonated polystyrene-block-polyethylene (PSS-PE) copolymer equilibrated in humid air with controlled relative humidity (RH), and in liquid water. Extrapolation of the domain size, water uptake, and conductivity obtained in humid air to RH = 100% allowed for an accurate comparison between the properties of PSS-PE hydrated in saturated vapor and in liquid water. We demonstrate that extrapolations of domain size and water uptake on samples equilibrated in humid air are consistent with measurements on samples equilibrated in liquid water. Small (5%) differences in proton conductivity were found in samples equilibrated in humid air and liquid water. We argue that differences in transport coefficients in disordered heterogeneous systems, particularly small differences, present no paradox whatsoever. Schroeder's Paradox, wherein properties of polymers measured in saturated water vapor are different from those obtained in liquid water, is thus not observed in the PSS-PE sample.
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| 23. |
- Chrysafi, Anna, et al.
(författare)
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Quantifying Earth system interactions for sustainable food production via expert elicitation
- 2022
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Ingår i: Nature Sustainability. - : Springer Science and Business Media LLC. - 2398-9629. ; 5:10, s. 830-842
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Tidskriftsartikel (refereegranskat)abstract
- Several safe boundaries of critical Earth system processes have already been crossed due to human perturbations; not accounting for their interactions may further narrow the safe operating space for humanity. Using expert knowledge elicitation, we explored interactions among seven variables representing Earth system processes relevant to food production, identifying many interactions little explored in Earth system literature. We found that green water and land system change affect other Earth system processes strongly, while land, freshwater and ocean components of biosphere integrity are the most impacted by other Earth system processes, most notably blue water and biogeochemical flows. We also mapped a complex network of mechanisms mediating these interactions and created a future research prioritization scheme based on interaction strengths and existing knowledge gaps. Our study improves the understanding of Earth system interactions, with sustainability implications including improved Earth system modelling and more explicit biophysical limits for future food production.
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| 24. |
- Cole, J.J., et al.
(författare)
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Plumbing the global carbon cycle : Integrating inland waters into the terrestrial carbon budget
- 2007
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Ingår i: Ecosystems (New York. Print). - : Springer Science and Business Media LLC. - 1432-9840 .- 1435-0629. ; 10:1, s. 172-185
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Forskningsöversikt (refereegranskat)abstract
- Because freshwater covers such a small fraction of the Earth’s surface area, inland freshwater ecosystems (particularly lakes, rivers, and reservoirs) have rarely been considered as potentially important quantitative components of the carbon cycle at either global or regional scales. By taking published estimates of gas exchange, sediment accumulation, and carbon transport for a variety of aquatic systems, we have constructed a budget for the role of inland water ecosystems in the global carbon cycle. Our analysis conservatively estimates that inland waters annually receive, from a combination of background and anthropogenically altered sources, on the order of 1.9 Pg C y−1 from the terrestrial landscape, of which about 0.2 is buried in aquatic sediments, at least 0.8 (possibly much more) is returned to the atmosphere as gas exchange while the remaining 0.9 Pg y−1 is delivered to the oceans, roughly equally as inorganic and organic carbon. Thus, roughly twice as much C enters inland aquatic systems from land as is exported from land to the sea. Over prolonged time net carbon fluxes in aquatic systems tend to be greater per unit area than in much of the surrounding land. Although their area is small, these freshwater aquatic systems can affect regional C balances. Further, the inclusion of inland, freshwater ecosystems provides useful insight about the storage, oxidation and transport of terrestrial C, and may warrant a revision of how the modern net C sink on land is described.
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| 25. |
- Downing, Andrea S., et al.
(författare)
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Effects of resources and mortality on the growth and reproduction of Nile perch in Lake Victoria
- 2013
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Ingår i: Freshwater Biology. - : Wiley. - 0046-5070 .- 1365-2427. ; 58:4, s. 828-840
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Tidskriftsartikel (refereegranskat)abstract
- 1. A collapse of Nile perch stocks of Lake Victoria could affect up to 30million people. Furthermore, changes in Nile perch population size-structure and stocks make the threat of collapse imminent. However, whether eutrophication or fishing will be the bane of Nile perch is still debated. 2. Here, we attempt to unravel how changes in food resources, a side effect of eutrophication, and fishing mortality determine fish population growth and size structures. We parameterised a physiologically structured model to Nile perch, analysed the influence of ontogenetic diet shifts and relative resource abundances on existence boundaries of Nile perch and described the populations on either side of these boundaries. 3. Our results showed that ignoring ontogenetic diet shifts can lead to over-estimating the maximum sustainable mortality of a fish population. Size distributions can be indicators of processes driving population dynamics. However, the vulnerability of stocks to fishing mortality is dependent on its environment and is not always reflected in size distributions. 4. We suggest that the ecosystem, instead of populations, should be used to monitor long-term effects of human impact.
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