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Shri Ashtapad Maha Tirth - II
The organism-based approach aims to clarify if the diversity hotspot in the south-eastern plateau originates from retreat of species from the plateau during cold climate episodes. Comparison of phenotypic and molecular markers like DMA, RNA sequencing, metagenomics or molecular clock approaches, will identify the diversity of resident organisms like soil micro-organisms and migrating plant or animal species. This will enable us to construct migration patterns of different groups of organisms. Additionally, Tip aims to identify physiological adaptation processes of resident organisms which is necessary to improve model parameterisation. Tip will use stable isotope for process integration necessary to evaluate model assumptions and palaeoclimate reconstructions. Consequently, isotope fractionation factors for 13C, 180 and 2H and transfer functions valid for the plateau have to be determined. The analysis of the geographical distribution of genetic variation using molecular tools (phylogeography) of selected plant species in combination with geomorphological and palaeoclimatic evidence will allow to identify the geographical location of glacial refugia and paths of postglacial (re-) colonization of the study area. Molecular phylogenetic analyses including a molecular clock approach will allow to identify the role of Quaternary climatic changes in plant diversification (as clearly demonstrated for European high mountain areas). Tip suggests manipulating the Kobresia pastures by fencing and systematic grazing on the plot level to determine the effect of overgrazing on pools and fluxes of carbon, nutrients and water on the plot size. Pulse labelling at permafrost and desert margins and pasture sites could help to detect changes in the above- and below ground food web structure and to determine changes in the organism interactions at these sites. These manipulations at transient ecosystems will give necessary information to estimate the effect of humans and climate change on the Tibetan ecosystems. TiP will evaluate hierarchical datasets provided from climate reconstructions, in situ measurements, and remote sensing to improve model parameterisation for regional and global climate simulations. TiP will perform systematic in situ measurements of energy and heat budget including hydrology fluxes for the main Tibetan ecotypes in order to close existing data gaps. Additionally TiP will determine meteorological data and trace gas concentrations and aerosols in the stable planetary boundary layer in order to evaluate the regional flux models and to understand the effect of vapour injections for the global circulation. TiP will implement the isofluxes of 180 and 2H in the regional and global climate simulation in order to scale between the recent climate processes and palaeoclimate proxy data derived from lake sediments or glaciers (see 3.2) and to evaluate the quality of model simulations. To predict the impact of changing climate and humans on the existing ecosystems TiP suggests model investigations and observation. TiP will use the improved models and tools developed from ecosystem and climate observations and manipulations in combination with palaeoinformation from 3.2 to make predictions on the ecosystem development and on their feedbacks to the global climate. TiP will focus on regional and global feedbacks derived from processes like permafrost melting, desertification, reforestation/deforestation or pollution with nutrient on the Tibetan Plateau. To evaluate the impact of humans on the regional climate system and their feedback to the global climate system TiP will use climate archives like glaciers, sediments and soils to identify Tibetan Plateau: Formation-Climate-Ecosystems
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