| title: | Impact of the bottom topography on the upper sediments lithological composition in Estonian small lakes |
|---|---|
| reg no: | ETF6857 |
| project type: | Estonian Science Foundation research grant |
| subject: |
1.11. Natural Geography (incl Meteorology, Geophysics) 1.16. Marine Sciences and Limnology |
| status: | accepted |
| institution: | Tallinna Ülikooli Ökoloogia Instituut |
| head of project: | Jaanus Terasmaa |
| duration: | 01.01.2006 - 31.12.2009 |
| description: | The importance of the proposed project lies in clarifying sedimentation processes in small lakes. A general aim of the project is to find out peculiarities of deposition and transformation processes in lakes to increase the trustworthiness of interpreting palaeogeographic information. For this purpose several small lakes of Estonia (Väike Juusa, Viitna Linajärv, Martiska, Ahnejärv, Jussi Pikkjärv, Ruusmäe, Alevijärv, etc) of different trophic state will be measured and sediment samples will be taken. The goals of the proposed project are: (1) clarification of peculiarities of the development of bottom sediments of small lakes in dependence of bottom topography, trophic state of the lake and surface cover and land use in the catchment area. (2) Verification and approbation of a composite parameter (CP) to create a possibility of its extensive use. (3) Development of methods suitable for delimitation of areas of different sedimentation regimes with the help of the suggested composite parameter with the aim of improving the trustworthiness of palaeolimnological reconstructions. (4) Improvement of transformation algorithms obtained through the analysis of upper sediment samples to raise the precision of palaeoresearch of sedimentation areas of different times. (5) Development and application of new methodological approaches. The hypothesis set in the project is that the lithological composition (especially grain size) of the bottom sediments of small lakes of stable settling reflects directly the location of the sampling point with respect to the shoreline, bottom topography and water depth during the formation of the sediment. Thus the material that forms the sediment is like a set of information carriers in which every particle/element carries knowledge about its origin and reasons for finding its place in the sediment. Combining cartographic methods with experimental and analytical ones and using the present spatial distribution of sedimentation areas it is possible to find out the distribution of these areas also in the past. As a result of the project a composite parameter suitable for small lakes will be developed, which enables to describe and compare small lakes of different shape, size and bottom relief. It is a parameter that transforms parameters describing the sampling point – its distance to the shore, water depth and slope inclination – into a dimensionless unit and combines the three into one composite parameter. This approach will create an opportunity to distinguish areas of different sedimentation regimes in a modern lake and, with the help of transformation algorithms developed in the framework of the grant project, also in the past. Another important output will be development and application of new methods. |
| project group | ||||
|---|---|---|---|---|
| no | name | institution | position | |
| 1. | Jaan-Mati Punning | |||
| 2. | Jaanus Terasmaa | Tallinna Ülikooli Ökoloogia Instituut | ||