| 1. |
- Kehoe, Laura, et al.
(författare)
-
Make EU trade with Brazil sustainable
- 2019
-
Ingår i: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 364:6438, s. 341-
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
|
|
| 2. |
|
|
| 3. |
- De Frenne, Pieter, et al.
(författare)
-
Microclimate moderates plant responses to macroclimate warming
- 2013
-
Ingår i: Proceedings of the National Academy of Sciences of the United States of America. - : Proceedings of the National Academy of Sciences. - 0027-8424 .- 1091-6490. ; 110:46, s. 18561-18565
-
Tidskriftsartikel (refereegranskat)abstract
- Recent global warming is acting across marine, freshwater, and terrestrial ecosystems to favor species adapted to warmer conditions and/or reduce the abundance of cold-adapted organisms (i.e., thermophilization of communities). Lack of community responses to increased temperature, however, has also been reported for several taxa and regions, suggesting that climatic lags may be frequent. Here we show that microclimatic effects brought about by forest canopy closure can buffer biotic responses to macroclimate warming, thus explaining an apparent climatic lag. Using data from 1,409 vegetation plots in European and North American temperate forests, each surveyed at least twice over an interval of 12-67 y, we document significant thermophilization of ground-layer plant communities. These changes reflect concurrent declines in species adapted to cooler conditions and increases in species adapted to warmer conditions. However, thermophilization, particularly the increase of warm-adapted species, is attenuated in forests whose canopies have become denser, probably reflecting cooler growing-season ground temperatures via increased shading. As standing stocks of trees have increased in many temperate forests in recent decades, local microclimatic effects may commonly be moderating the impacts of macroclimate warming on forest understories. Conversely, increases in harvesting woody biomass-e.g., for bioenergy-may open forest canopies and accelerate thermophilization of temperate forest biodiversity.
|
|
| 4. |
- De Frenne, Pieter, et al.
(författare)
-
Plant movements and climate warming : intraspecific variation in growth responses to nonlocal soils
- 2014
-
Ingår i: New Phytologist. - : Wiley. - 0028-646X .- 1469-8137. ; 202:2, s. 431-441
-
Tidskriftsartikel (refereegranskat)abstract
- Most range shift predictions focus on the dispersal phase of the colonization process. Because moving populations experience increasingly dissimilar nonclimatic environmental conditions as they track climate warming, it is also critical to test how individuals originating from contrasting thermal environments can establish in nonlocal sites. We assess the intraspecific variation in growth responses to nonlocal soils by planting a widespread grass of deciduous forests (Milium effusum) into an experimental common garden using combinations of seeds and soil sampled in 22 sites across its distributional range, and reflecting movement scenarios of up to 1600km. Furthermore, to determine temperature and forest-structural effects, the plants and soils were experimentally warmed and shaded. We found significantly positive effects of the difference between the temperature of the sites of seed and soil collection on growth and seedling emergence rates. Migrant plants might thus encounter increasingly favourable soil conditions while tracking the isotherms towards currently colder' soils. These effects persisted under experimental warming. Rising temperatures and light availability generally enhanced plant performance. Our results suggest that abiotic and biotic soil characteristics can shape climate change-driven plant movements by affecting growth of nonlocal migrants, a mechanism which should be integrated into predictions of future range shifts.
|
|
| 5. |
- Tóth, Peter, et al.
(författare)
-
Radiocarbin dating of grass-tempered ceramic reveals the earliest pottery from Slovakia predates the arrival of farming
- 2023
-
Ingår i: Radiocarbon. - 0033-8222 .- 1945-5755. ; 65:3, s. 733-753
-
Tidskriftsartikel (refereegranskat)abstract
- In the absence of wood, bone, and other organics, one possible candidate for determining the age of a site is the radiocarbon (14C) dating of pottery. In central Europe during the Early Neolithic, pottery was ubiquitous and contained substantial quantities of organic temper. However, attempts at the direct dating of organic inclusions raises a lot of methodological issues, especially when several sources of carbon contribute to the resulting radiocarbon age. Hence an alternative approach to dating of the early pottery is necessary. Here, we present a novel method of bulk separation of organic content from the grass-tempered pottery from Santovka (Slovakia). The procedure is based on the consecutive application of three inorganic acids, dissolving clay, silica content, and low molecular or mobile fractions to separate organic inclusions added to the pottery matrix during the formation of vessels. Radiocarbon dates obtained with this method are coherent and produce the shortest time span compared to other pretreatment methods presented in this study. The paired dates of grass-tempered pots with the 14C age of lipids extracted from the same pots point to a difference of 400–600 14C yr, however they are in line with the site’s chronostratigraphic Bayesian model. Grass-tempered pottery from Santovka (Slovakia) is dated to the first half of the 6th millennium cal BC, making it the earliest pottery north of the Danube. It seems feasible that ceramic containers from Santovka were produced by hunter-gatherers, and pottery predated the arrival of farming in the Carpathian region by a couple of centuries.
|
|
| 6. |
- Verheyen, Kris, et al.
(författare)
-
201 Combining Biodiversity Resurveys across Regions to Advance Global Change Research
- 2017
-
Ingår i: BioScience. - : Oxford University Press (OUP). - 0006-3568 .- 1525-3244. ; 67:1, s. 73-83
-
Tidskriftsartikel (refereegranskat)abstract
- More and more ecologists have started to resurvey communities sampled in earlier decades to determine long-term shifts in community composition and infer the likely drivers of the ecological changes observed. However, to assess the relative importance of and interactions among multiple drivers, joint analyses of resurvey data from many regions spanning large environmental gradients are needed. In this article, we illustrate how combining resurvey data from multiple regions can increase the likelihood of driver orthogonality within the design and show that repeatedly surveying across multiple regions provides higher representativeness and comprehensiveness, allowing us to answer more completely a broader range of questions. We provide general guidelines to aid the implementation of multiregion resurvey databases. In so doing, we aim to encourage resurvey database development across other community types and biomes to advance global environmental change research.
|
|
| 7. |
- Verheyen, Kris, et al.
(författare)
-
Driving factors behind the eutrophication signal in understorey plant communities of deciduous temperate forests
- 2012
-
Ingår i: Journal of Ecology. - : Wiley. - 0022-0477 .- 1365-2745. ; 100:2, s. 352-365
-
Tidskriftsartikel (refereegranskat)abstract
- 1. Atmospheric nitrogen (N) deposition is expected to change forest understorey plant community composition and diversity, but results of experimental addition studies and observational studies are not yet conclusive. A shortcoming of observational studies, which are generally based on resurveys or sampling along large deposition gradients, is the occurrence of temporal or spatial confounding factors. 2. We were able to assess the contribution of N deposition versus other ecological drivers on forest understorey plant communities by combining a temporal and spatial approach. Data from 1205 (semi-)permanent vegetation plots taken from 23 rigorously selected understorey resurvey studies along a large deposition gradient across deciduous temperate forest in Europe were compiled and related to various local and regional driving factors, including the rate of atmospheric N deposition, the change in large herbivore densities and the change in canopy cover and composition. 3. Although no directional change in species richness occurred, there was considerable floristic turnover in the understorey plant community and a shift in species composition towards more shade-tolerant and nutrient-demanding species. However, atmospheric N deposition was not important in explaining the observed eutrophication signal. This signal seemed mainly related to a shift towards a denser canopy cover and a changed canopy species composition with a higher share of species with more easily decomposed litter. 4. Synthesis. Our multi-site approach clearly demonstrates that one should be cautious when drawing conclusions about the impact of atmospheric N deposition based on the interpretation of plant community shifts in single sites or regions due to other, concurrent, ecological changes. Even though the effects of chronically increased N deposition on the forest plant communities are apparently obscured by the effects of canopy changes, the accumulated N might still have a significant impact. However, more research is needed to assess whether this N time bomb will indeed explode when canopies will open up again.
|
|
