| 1. |
- Moss, Brian D., et al.
(författare)
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Climate change and the future of freshwater biodiversity in Europe : a primer for policy-makers
- 2009
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Ingår i: Freshwater Reviews. - : Freshwater Biological Association. - 1755-084X. ; 2:2, s. 103-130
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Tidskriftsartikel (refereegranskat)abstract
- Earth's climate is changing, and by the end of the 21st century in Europe, average temperatures are likely to have risen by at least 2 °C, and more likely 4 °C with associated effects on patterns of precipitation and the frequency of extreme weather events. Attention among policy-makers is divided about how to minimise the change, how to mitigate its effects, how to maintain the natural resources on which societies depend and how to adapt human societies to the changes. Natural systems are still seen, through a long tradition of conservation management that is largely species-based, as amenable to adaptive management, and biodiversity, mostly perceived as the richness of plant and vertebrate communities, often forms a focus for planning. We argue that prediction of particular species changes will be possible only in a minority of cases but that prediction of trends in general structure and operation of four generic freshwater ecosystems (erosive rivers, depositional floodplain rivers, shallow lakes and deep lakes) in three broad zones of Europe (Mediterranean, Central and Arctic-Boreal) is practicable. Maintenance and rehabilitation of ecological structures and operations will inevitably and incidentally embrace restoration of appropriate levels of species biodiversity. Using expert judgement, based on an extensive literature, we have outlined, primarily for lay policy makers, the pristine features of these systems, their states under current human impacts, how these states are likely to alter with a warming of 2 °C to 4 °C and what might be done to mitigate this. We have avoided technical terms in the interests of communication, and although we have included full referencing as in academic papers, we have eliminated degrees of detail that could confuse broad policy-making
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| 2. |
- Dudley, Bernard J., et al.
(författare)
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Measurements of uncertainty in macrophyte metrics used to assess European lake water quality
- 2013
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Ingår i: Hydrobiologia. - : Springer Science and Business Media LLC. - 0018-8158 .- 1573-5117. ; 704:1, s. 179-191
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Tidskriftsartikel (refereegranskat)abstract
- Uncertainty is an important factor in ecological assessment, and has important implications for the ecological classification and management of lakes. However, our knowledge of the effects of uncertainty in the assessment of different ecological indicators is limited. Here, we used data from a standardized campaign of aquatic plant surveys, in 28 lakes from 10 European countries, to assess variation in macrophyte metrics across a set of nested spatial scales: countries, lakes, sampling stations, replicate transects, and replicate samples at two depth-zones. Metrics investigated in each transect included taxa richness, maximum depth of colonisation and two indicators of trophic status: Ellenberg’s N and a metric based on phosphorus trophic status. Metrics were found to have a slightly stronger relationship to pressures when they were calculated on abundance data compared to presence/absence data. Eutrophication metrics based on helophytes were found not to be useful in assessing the effects of nutrient pressure. These metrics were also found to vary with the depth of sampling, with shallower taxa representing higher trophic status. This study demonstrates the complex spatial variability in macrophyte communities, the effect of this variability on the metrics, and theimplications to water managers, especially in relation to survey design.
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| 3. |
- Menkveld, Albert J., et al.
(författare)
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Nonstandard Errors
- 2024
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Ingår i: JOURNAL OF FINANCE. - : Wiley-Blackwell. - 0022-1082 .- 1540-6261. ; 79:3, s. 2339-2390
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Tidskriftsartikel (refereegranskat)abstract
- In statistics, samples are drawn from a population in a data-generating process (DGP). Standard errors measure the uncertainty in estimates of population parameters. In science, evidence is generated to test hypotheses in an evidence-generating process (EGP). We claim that EGP variation across researchers adds uncertainty-nonstandard errors (NSEs). We study NSEs by letting 164 teams test the same hypotheses on the same data. NSEs turn out to be sizable, but smaller for more reproducible or higher rated research. Adding peer-review stages reduces NSEs. We further find that this type of uncertainty is underestimated by participants.
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| 4. |
- Spears, Bryan M., et al.
(författare)
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Geo-Engineering in Lakes-A Call for Consensus
- 2013
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Ingår i: Environmental Science and Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 47:9, s. 3953-3954
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
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| 5. |
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- 2019
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Tidskriftsartikel (refereegranskat)
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