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Dive into the research topics where Ralf Ohlemüller is active.

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Featured researches published by Ralf Ohlemüller.


Science | 2011

Rapid Range Shifts of Species Associated with High Levels of Climate Warming

I-Ching Chen; Jane K. Hill; Ralf Ohlemüller; David B. Roy; Chris D. Thomas

A meta-analysis shows that species are shifting their distributions in response to climate change at an accelerating rate. The distributions of many terrestrial organisms are currently shifting in latitude or elevation in response to changing climate. Using a meta-analysis, we estimated that the distributions of species have recently shifted to higher elevations at a median rate of 11.0 meters per decade, and to higher latitudes at a median rate of 16.9 kilometers per decade. These rates are approximately two and three times faster than previously reported. The distances moved by species are greatest in studies showing the highest levels of warming, with average latitudinal shifts being generally sufficient to track temperature changes. However, individual species vary greatly in their rates of change, suggesting that the range shift of each species depends on multiple internal species traits and external drivers of change. Rapid average shifts derive from a wide diversity of responses by individual species.


Biology Letters | 2008

The coincidence of climatic and species rarity: high risk to small-range species from climate change.

Ralf Ohlemüller; Barbara J. Anderson; Miguel B. Araújo; Stuart H. M. Butchart; Otakar Kudrna; Robert S Ridgely; Chris D. Thomas

Why do areas with high numbers of small-range species occur where they do? We found that, for butterfly and plant species in Europe, and for bird species in the Western Hemisphere, such areas coincide with regions that have rare climates, and are higher and colder areas than surrounding regions. Species with small range sizes also tend to occur in climatically diverse regions, where species are likely to have been buffered from extinction in the past. We suggest that the centres of high small-range species richness we examined predominantly represent interglacial relict areas where cold-adapted species have been able to survive unusually warm periods in the last ca 10 000 years. We show that the rare climates that occur in current centres of species rarity will shrink disproportionately under future climate change, potentially leading to high vulnerability for many of the species they contain.


Biological Reviews | 2010

Multiple stressors on biotic interactions: how climate change and alien species interact to affect pollination

Oliver Schweiger; Jacobus C. Biesmeijer; Riccardo Bommarco; Thomas Hickler; Philip E. Hulme; Stefan Klotz; Ingolf Kühn; Mari Moora; Anders Nielsen; Ralf Ohlemüller; Theodora Petanidou; Simon G. Potts; Petr Pyšek; Jane C. Stout; Martin T. Sykes; Thomas Tscheulin; Montserrat Vilà; Gian-Reto Walther; Catrin Westphal; Marten Winter; Martin Zobel; Josef Settele

Global change may substantially affect biodiversity and ecosystem functioning but little is known about its effects on essential biotic interactions. Since different environmental drivers rarely act in isolation it is important to consider interactive effects. Here, we focus on how two key drivers of anthropogenic environmental change, climate change and the introduction of alien species, affect plant–pollinator interactions. Based on a literature survey we identify climatically sensitive aspects of species interactions, assess potential effects of climate change on these mechanisms, and derive hypotheses that may form the basis of future research. We find that both climate change and alien species will ultimately lead to the creation of novel communities. In these communities certain interactions may no longer occur while there will also be potential for the emergence of new relationships. Alien species can both partly compensate for the often negative effects of climate change but also amplify them in some cases. Since potential positive effects are often restricted to generalist interactions among species, climate change and alien species in combination can result in significant threats to more specialist interactions involving native species.


Evolution | 2010

CLIMATE PREDICTORS OF LATE QUATERNARY EXTINCTIONS

David Nogués-Bravo; Ralf Ohlemüller; Persaram Batra; Miguel B. Araújo

Between 50,000 and 3,000 years before present (BP) 65% of mammal genera weighing over 44 kg went extinct, together with a lower proportion of small mammals. Why species went extinct in such large numbers is hotly debated. One of the arguments proposes that climate changes underlie Late Quaternary extinctions, but global quantitative evidence for this hypothesis is still lacking. We test the potential role of global climate change on the extinction of mammals during the Late Quaternary. Our results suggest that continents with the highest climate footprint values, in other words, with climate changes of greater magnitudes during the Late Quaternary, witnessed more extinctions than continents with lower climate footprint values, with the exception of South America. Our results are consistent across species with different body masses, reinforcing the view that past climate changes contributed to global extinctions. Our model outputs, the climate change footprint dataset, provide a new research venue to test hypotheses about biodiversity dynamics during the Late Quaternary from the genetic to the species richness level.


Philosophical Transactions of the Royal Society B | 2013

A greener Greenland? Climatic potential and long-term constraints on future expansions of trees and shrubs.

Signe Normand; Christophe F. Randin; Ralf Ohlemüller; Christian Bay; Toke T. Høye; Erik Dahl Kjær; Christian Körner; Heike Lischke; Luigi Maiorano; Jens Paulsen; Achilleas Psomas; Urs A. Treier; Niklaus E. Zimmermann; Jens-Christian Svenning

Warming-induced expansion of trees and shrubs into tundra vegetation will strongly impact Arctic ecosystems. Today, a small subset of the boreal woody flora found during certain Plio-Pleistocene warm periods inhabits Greenland. Whether the twenty-first century warming will induce a re-colonization of a rich woody flora depends on the roles of climate and migration limitations in shaping species ranges. Using potential treeline and climatic niche modelling, we project shifts in areas climatically suitable for tree growth and 56 Greenlandic, North American and European tree and shrub species from the Last Glacial Maximum through the present and into the future. In combination with observed tree plantings, our modelling highlights that a majority of the non-native species find climatically suitable conditions in certain parts of Greenland today, even in areas harbouring no native trees. Analyses of analogous climates indicate that these conditions are widespread outside Greenland, thus increasing the likelihood of woody invasions. Nonetheless, we find a substantial migration lag for Greenlands current and future woody flora. In conclusion, the projected climatic scope for future expansions is strongly limited by dispersal, soil development and other disequilibrium dynamics, with plantings and unintentional seed dispersal by humans having potentially large impacts on spread rates.


Science | 2011

Running Out of Climate Space

Ralf Ohlemüller

Mapping the speed of climate change helps to explain and predict biodiversity patterns on land and in the sea. Current biodiversity patterns across the globe are the result of the interplay between past and current climates and the degree to which species respond to these conditions (1). Climate affects both evolutionary processes, such as how fast species diversify, and ecological processes such as range shifts and species interactions. Understanding the spatial distribution of climatic conditions over time is thus crucial for understanding current and likely future species distributions and biodiversity patterns. Two reports in this issue, by Burrows et al. on page 652 (2) and Sandel et al. on page 660 (3), investigate past and future shifts in climate space, with the aim to explain and predict biogeographical patterns.


Plant Ecology | 2010

The Iberian Peninsula as a potential source for the plant species pool in Germany under projected climate change

Jessica Bergmann; Sven Pompe; Ralf Ohlemüller; Martin Freiberg; Stefan Klotz; Ingolf Kühn

The application of niche-based modelling techniques to plant species has not been explored for the majority of taxa in Europe, primarily due to the lack of adequate distributional data. However, it is of crucial importance for conservation adaptation decisions to assess and quantify the likely pool of species capable of colonising a particular region under altered future climate conditions. We here present a novel method that combines the species pool concept and information about shifts in analogous multidimensional climate space. This allows us to identify regions in Europe with a current climate which is similar to that projected for future time periods in Germany. We compared the extent and spatial location of climatically analogous European regions for three projected greenhouse gas emission scenarios in Germany for the time period 2071–2080 (+2.4°C, +3.3°C, +4.5°C average increase in mean annual temperature) to those of the recent past in Europe (1961–90). Across all three scenarios, European land areas which are characterised by climatic conditions analogue to those found in Germany decreased from 14% in 1961–1990 to ca. 10% in 2071–2080. All scenarios show disappearing current climate types in Germany, which can mainly be explained with a general northwards shift of climatically analogous regions. We estimated the size of the potential species pool of these analogous regions using floristic inventory data for the Iberian Peninsula as 2,354 plant species. The identified species pool in Germany indicates a change towards warmth and drought adapted southern species. About one-third of the species from the Iberian analogous regions are currently already present in Germany. Depending on the scenario used, 1,372 (+2.4°C average change of mean annual temperature), 1,399 (+3.3°C) and 1,444 (+4.5°C) species currently not found in Germany, occur in Iberian regions which are climatically analogous to German 2071–80 climate types. We believe that our study presents a useful approach to illustrate and quantify the potential size and spatial distribution of a pool of species potentially colonising new areas under changing climatic conditions.


Environmental Modeling & Assessment | 2013

Modelling Interactions Between Economic Activity, Greenhouse Gas Emissions, Biodiversity and Agricultural Production

Manfred Lenzen; Christopher Dey; Barney Foran; Asaph Widmer-Cooper; Ralf Ohlemüller; Moira C. Williams; Thomas Wiedmann

In this article, we develop a modelling approach which examines selected drivers of ecosystem functioning and agricultural productivity. In particular, we develop linkages between land use and biodiversity and between biodiversity and agricultural productivity. We review the literature for quantitative estimates of key relationships and their parameters for modelling human consumption, land use, energy use, and greenhouse gas emissions on biodiversity and agricultural productivity. We assemble these specifications into an iterative causal model and carry out a number of scenario projections of country-level consumption, production, land use, energy use, greenhouse gas emissions, species diversity, and agricultural production up to 2050. Finally, we dissect the projections into key drivers using structural decomposition and sensitivity analyses.


EMBO Reports | 2008

Exporting the ecological effects of climate change: Developed and developing countries will suffer the consequences of climate change, but differ in both their responsibility and how badly it will affect their ecosystems

Chris D. Thomas; Ralf Ohlemüller; Barbara J. Anderson; Thomas Hickler; Paul A. Miller; Martin T. Sykes; John W. Williams

Global anthropogenic climate change is contributing to the considerable economic imbalance between rich and poor nations. The changing climate will inevitably influence natural resources, but it is the poorest countries—where humans rely most directly on natural systems for their livelihoods—that are expected to experience the greatest changes. Accordingly, the resources, economies and societies of these nations are likely to be most severely affected, despite the fact that they are least able to cope with—and are least responsible for—climate change itself. Here, we analyse which countries and regions will suffer the most severe changes to their natural ecosystems and biodiversity, and how the responsibility for those changes is distributed across the world. > The changing climate will inevitably influence natural resources, but it is the poorest countries […] that are expected to experience the greatest changes On a broad scale, geographic variations in temperature, rainfall and seasonality determine ecosystem productivity and species diversity. Ecosystems therefore respond to changes in temperature and precipitation, which inevitably have an impact on biodiversity. Recent shifts in the distributions of various species towards the poles and to higher altitudes (Parmesan & Yohe, 2003; Root et al , 2003; Walther et al , 2005; Wilson et al , 2005; Franco et al , 2006; Hickling et al , 2006), and the extinction of more than 1% of all amphibian species (Pounds et al , 2006), indicate that climate change is already having a major impact on biodiversity. Climatic changes are also expected to alter the distributions of most types of vegetation (Cramer et al , 2001; Scholtze et al , 2006) and there is already evidence of a shift from deciduous woodland to evergreen forest in part of southern Europe (Walther et al , 2002). Such changes will have implications both for biodiversity (Malcolm et al , 2006) and for the humans …


Biodiversity Information Science and Standards | 2018

Books and Drawers full of Moths

Kane Fleury; Emma Burns; Barbara J. Anderson; Robert Hoare; Ralf Ohlemüller

The Otago Museum houses one of New Zealand’s largest Lepidoptera collections that consists of more than 31,000 macro moth specimens collected across New Zealand over the last 30 years. Alongside this collection, supplementary information is found in detailed field notebooks that cover, for most sites, the total abundance of the different species present in these samples. We have been able to use the notebooks to work out the sampling intensity and sites to map both the collections and the abundances to some degree. It is impractical to collect everything. As a result, the common species are left out of collections and the rare and unusual sightings fill the collections. When planning to resample collecting sites to investigate changes in ecosystems, just relying on collections for species presence and absence would skew the results. It should also be noted that field notebooks are not a panacea for biological information as the information in them ages, so too can the reliability and accuracy of the notes within. Here we discuss how the field notebook data compares with the information accompanying the specimens housed within the museum collection. This is a recently digitised collection and allows an insight into the collectors sampling, vouchering and data practices and how these can affect modern interpretation and variation in repeat sampling. ‡ ‡ § | ¶

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Ingolf Kühn

Helmholtz Centre for Environmental Research - UFZ

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Miguel B. Araújo

Spanish National Research Council

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Stefan Klotz

Helmholtz Centre for Environmental Research - UFZ

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