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2 Posts tagged with the china tag
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Life Sciences Seminar


Inferring the diversification of land plants at and in the shadow of the Roof of the World

 

Harald Schneider

Plants, Dept. of Life Sciences, NHM

 

Wednesday 12 of December 11:00
Sir Neil Chalmers seminar room, Darwin Centre LG16 (below Attenborough studio)


Orogenic events in earth history, e.g. mountain formation, have made a profound impact on the assembly of biological diversity. For example, recent studies of the biodiversity of South America recovered strong evidence that the Cenozoic rise of the Andeans triggered the rapid diversification of many lineages of vascular plants.

 

However, relatively little attention has been given to the effect of the rise of the Himalaya on plant diversity. The rise of this mountain chains were triggered by the collision of the Indian tectonic plate with the Eurasian continent 70 million years ago but major uplifts date back to more recent times. Especially the rather recent formation of the Qinghai-Tibetan plateau, around 3-4 million years ago, had a considerable impact on the monsoon climates in South East Asia. Thus the rise of this plateau affected not only the evolution of plants adapted to the alpine conditions at the high altitudes of the Himalaya but also the expansion of xeric habitats in central Asia and the enhanced monsoons affecting South East Asia and South Asia.

 

The hypothesis of the impact of the rise of the Himalaya on plant diversity in South East Asia is studied employing mainly phylogenetic approaches that incorporate divergence time estimates, ancestral area reconstruction, inference of niche evolution, and estimates of diversification rates. The analyses also incorporate evidence from micro-paleontological research.

 

Comparative assessment of the existing and newly generated phylogenetic hypotheses for a wide range of angiosperms and ferns recovered evidence supporting the hypothesis of a substantial impact of the rise of the Qinghai-Tibetan plateau on the assembly of lineage diversity. This result is consistent with palaeoclimate reconstructions that are based on pollen and spore record. In comparison, the recovered patterns indicate the involvement of different processes in response to the Cenozoic mountain formations in South America and South East Asia.

 

The presentation summarises research that was carried out during my time as a senior visiting professor of the Chinese Academy of Sciences. Besides the presentation of the results of the research, I will also touch on issues related to the current research conditions in China.

 

Harald Schneider

 

 

 

For additional details on attending this or other seminars see http://www.nhm.ac.uk/research-curation/seminars-events/index.html

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Department of Life Sciences seminar

 

Insect diversity and pest control in the anthropogenic habitats of NE China

 

Jan Axmacher

Department of Geography, University College London

 

Friday 7 December 11:00
Sir Neil Chalmers seminar room, Darwin Centre LG16 (below Attenborough studio)

 

 

The natural environment of NE China has been altered by humans for thousands of years. Nonetheless, both intensity and spatial extend of these alterations have greatly increased since the middle of the last century. Agricultural production was greatly intensified, while the remaining natural forest cover was widely cleared. The severe environmental degradation which followed has led to an increased awareness of the importance of environmental issues in the last few decades, with re- and afforestation projects being currently established throughout China at an unprecedented scale. At the same time, agricultural practices following the maxim ‘the more, the better’ are also increasingly questioned, with the importance of biological pest control recognized as a potential cheap and less environmentally detrimental alternative to chemical pesticides.

 

Given these recent developments, I have started a number of collaborative research projects with the Chinese Agricultural University and the Institute of Botany, Chinese Academy of Sciences to investigate diversity and species composition of ground beetle assemblages in reforested habitats and the agricultural landscapes of the Hebei province, looking at both the diversity and potential pest control function of these mostly predatory beetles. Our research shows that the diversity of ground beetles varies strongly between different types of forest ecosystems, with naturally regenerating birch forests and open larch plantations showing a high abundance, but low diversity in carabids. Plantations of native oak and pine monocultures, as well as forests composed of a mixture of planted and naturally regenerating trees harbour distinctly higher diversity levels.

 

In the agricultural landscape, even very intensively managed double-cropping systems comprising of summer maize and winter wheat monocultures can support surprisingly high levels of ground beetle diversity, while cotton monocultures were found to harbour distinctly lower levels of carabid diversity. Landscape elements like the diversity of land-use types were found to have only a limited effect on the diversity of the ground beetle community at least in some of our study areas. A comparison of diversity patterns in ground beetles and geometrid moths finally showed that links between these highly diverse herbivore and insectivore taxa are highly complex, with distinctly different spatial patterns observed in these two families.

 

 

 

For additional details on attending this or other seminars see http://www.nhm.ac.uk/research-curation/seminars-events/index.html