| 11. |
- Eklöf, Johan, 1978, et al.
(författare)
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Experimental climate change weakens the insurance effect of biodiversity
- 2012
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Ingår i: Ecology Letters. - : Wiley. - 1461-023X .- 1461-0248. ; 15:8, s. 864-872
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Tidskriftsartikel (refereegranskat)abstract
- Ecosystems are simultaneously affected by biodiversity loss and climate change, but we know little about how these factors interact. We predicted that climate warming and CO 2-enrichment should strengthen trophic cascades by reducing the relative efficiency of predation-resistant herbivores, if herbivore consumption rate trades off with predation resistance. This weakens the insurance effect of herbivore diversity. We tested this prediction using experimental ocean warming and acidification in seagrass mesocosms. Meta-analyses of published experiments first indicated that consumption rate trades off with predation resistance. The experiment then showed that three common herbivores together controlled macroalgae and facilitated seagrass dominance, regardless of climate change. When the predation-vulnerable herbivore was excluded in normal conditions, the two resistant herbivores maintained top-down control. Under warming, however, increased algal growth outstripped control by herbivores and the system became algal-dominated. Consequently, climate change can reduce the relative efficiency of resistant herbivores and weaken the insurance effect of biodiversity.
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| 12. |
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| 13. |
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| 14. |
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| 15. |
- Gamfeldt, Lars, 1975, et al.
(författare)
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Biodiversity effects on aquatic ecosystem functioning - maturation of a new paradigm
- 2008
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Ingår i: International Review of Hydrobiology. ; 93:4-5, s. 550-564
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Tidskriftsartikel (refereegranskat)abstract
- Starting with the publication of some influential studies in the early 1990’s, the topic of biodiversity and ecosystem functioning has emerged as a major field within ecological research. Within this framework, the diversity of genotypes, species and functional groups are considered as explanatory variables of ecosystem functions rather than response variables of factors such as productivity and disturbance. Biodiversity-ecosystem functioning research has received considerable attention, and new publications are emerging at a high pace. Both the validity of experimental approaches and the way the results may be extrapolated to natural systems have, however, been widely discussed. The width of the debate regarding whether or not biodiversity is important for ecosystem functioning have encouraged many scientists to refine both experiments and theory, as well as develop novel methods to analyse the relationship between diversity and functioning. Aquatic ecologists have contributed greatly to the evolution of ideas and concepts within the field. In this review, we discuss how the paradigm that biodiversity is an important factor for the functioning of aquatic ecosystems is currently maturing with more realistic studies embracing both new and innovative approaches. We also suggest fruitful areas for future research.
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| 16. |
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| 17. |
- Gamfeldt, Lars, 1975, et al.
(författare)
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Higher levels of multiple ecosystem services are found in forests with more tree species
- 2013
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Ingår i: Nature Communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 4
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Tidskriftsartikel (refereegranskat)abstract
- Forests are of major importance to human society, contributing several crucial ecosystem services. Biodiversity is suggested to positively influence multiple services but evidence from natural systems at scales relevant to management is scarce. Here, across a scale of 400,000km2, we report that tree species richness in production forests shows positive to positively hump-shaped relationships with multiple ecosystem services. These include production of tree biomass, soil carbon storage, berry production and game production potential. For example, biomass production was approximately 50% greater with five than with one tree species. In addition, we show positive relationships between tree species richness and proxies for other biodiversity components. Importantly, no single tree species was able to promote all services, and some services were negatively correlated to each other. Management of production forests will therefore benefit from considering multiple tree species to sustain the full range of benefits that the society obtains from forests.
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| 18. |
- Gamfeldt, Lars, 1975, et al.
(författare)
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Increasing intraspecific diversity enhances settling success in a marine invertebrate
- 2005
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Ingår i: Ecology. - : Wiley. - 0012-9658. ; 86:12, s. 3219-3224
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Tidskriftsartikel (refereegranskat)abstract
- Theoretical and empirical research during the last decade suggests that increasing species richness often enhances ecosystem processes Such as productivity, nutrient cycling. or resistance to disturbance. By analogous reasoning, it can be hypothesized that genetic diversity within species will have equivalent effects; however, this hypothesis has rarely been tested. We present experimental support for the positive effects of intraspecific diversity on a key trait: larval settlement in a marine invertebrate, the barnacle Balanus improvisus. Varying within-species diversity levels of an animal over nine experiments, We found increasing larval settlement with increasing diversity (one, two, or three parental broods). Possible mechanisms explaining this pattern include: (1) facilitation of gregarious response through the presence of founder genotypes, and (2) ensuring genetic complementarity to increase future reproductive potential. Our results indicate that changing intraspecific genetic diversity could have hitherto unrecognized community-scale implications for larval recruitment and space occupancy.
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| 19. |
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| 20. |
- Gamfeldt, Lars, 1975, et al.
(författare)
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Marine biodiversity and ecosystem functioning: What's known and what's next?
- 2015
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Ingår i: Oikos. - : Wiley. - 0030-1299 .- 1600-0706. ; 124:3, s. 252-265
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Tidskriftsartikel (refereegranskat)abstract
- Marine ecosystems are experiencing rapid and pervasive changes in biodiversity and species composition. Understanding the ecosystem consequences of these changes is critical to effectively managing these systems. Over the last several years, numerous experimental manipulations of species richness have been performed, yet existing quantitative syntheses have focused on a just a subset of processes measured in experiments and, as such, have not summarized the full data available from marine systems. Here, we present the results of a meta-analysis of 110 marine experiments from 42 studies that manipulated the species richness of organisms across a range of taxa and trophic levels and analysed the consequences for various ecosystem processes (categorised as production, consumption or biogeochemical fluxes). Our results show that, generally, mixtures of species tend to enhance levels of ecosystem function relative to the average component species in monoculture, but have no effect or a negative effect on functioning relative to the 'highest- performing' species. These results are largely consistent with those from other syntheses, and extend conclusions to ecological functions that are commonly measured in the marine realm (e.g. nutrient release from sediment bioturbation). For experiments that manipulated three or more levels of richness, we attempted to discern the functional form of the biodiversity-ecosystem functioning relationship. We found that, for response variables related to consumption, a power-function best described the relationship, which is also consistent with previous findings. However, we identified a linear relationship between richness and production. Combined, our results suggest that changes in the number of species will, on average, tend to alter the functioning of marine ecosystems. We outline several research frontiers that will allow us to more fully understand how, why, and when diversity may drive the functioning of marine ecosystems. Synthesis The oceans host an incredible number and variety of species. However, human activities are driving rapid changes in the marine environment. It is imperative we understand ecosystem consequences of any associated loss of species. We summarized data from 110 experiments that manipulated species diversity and evaluated resulting changes to a range of ecosystem responses. We show that losing species, on average, decreases productivity, growth, and a myriad of other processes related to how marine organisms capture and utilize resources. Finally, we suggest that the loss of species may have stronger consequences for some processes than others.
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