Abschlussarbeiten - Exp. Pflanzenökologie


Im Folgenden findest Du die Themenvorschläge für Bachelor- (BA) und Masterarbeiten (MA), nach ihrem potentiellen Startpunkt geordnet.

Themen können in den meisten Fällen an eigene Interessen angepasst werden und eigene Themenvorschläge sind immer wilkommen und können wenn erwünscht gerne mit unserer Unterstützung entwickelt werden!

Bei Interesse sprich uns einfach mal an!

 

Hier findest Du eine hilfreiche Einführung in das wissenschaftliche Arbeiten:

Wissenschaftliches Arbeiten im Rahmen von Seminaren & Abschlussarbeiten

Hier noch eine kurze Anleitung zur Installation von R:

Installing R


Die AG „Experimentelle Pflanzenökologie“ schreibt für 2021/22 folgende Themen für B.Sc.- und M.Sc.-Arbeiten aus:


Using tree rings to evaluate growth performance under seasonal warming

Time plan: May to August 2022.
Contact: Dr. Andrey Malyshev andrey.malyshev@uni-greifswald.de
 

Background:
Plant phenology determines the length of a plant’s growing season and plays a major role in the net
productivity of an ecosystem. Differences in seasonal tree growth in individual trees are observable via
tree ring growth under a microscope (Figure 1). Groups of beech and birch trees (Fagus sylvatica and
Betula pendula have been exposed to seasonal warming (spring and/or autumn warming) and the timing
of fall senescence as well as spring leaf-out have has been documented. The relative impact of shifts in
leaf phenology on actual tree growth now needs to be determined to identify periods of warming which
cause the greatest growth increase in these two tree species.

Potential research questions:


1) Does an earlier leaf out or later leaf senescence cause greater wood formation?
2) How does leaf phenology and the resulting wood formation differ between beech and birch?
 

Methods:

Preparation of wood cross sections from young trees (see Figure 1) and analyzing the images
via tree ring analysis software.


Comparing phenology of beech saplings form different regions of Europe

 

-topic already assigned-

Background:

Plants phenology is adapted to the climate at the place where they grow in a way that they optimise 

Plants phenology is typically optimized in a way that the growing season is a long as possible while the risk of freezing is as low as possible. In a widespread species like Fagus sylvatica (European beech) one would expect that different ecotypes, developed in different regions of Europe, show some variation regarding spring and maybe even autumn phenology. If climate is now getting warmer and winters become shorter, plants with earlier leaf out strategies in spring and later autumn coloration might be at an advantage, because they have more time to grow over the year. An early onset of growth is even more important when the likelihood of summer drought is rising.

Methods:

We planted beech seedlings originating from different regions in Europe into the forest near Hanshagen following a randomized block design. After establishment in 2020 they are now ready for comparing the spring and possibly autumn phenology of the different provenances (ecotypes). Biweekly observations in spring and weekly observations in autumn will tell us, which ones are the early trees, and which ones are the late ones.

Do you like to work in the forest at the most beautiful time of the year? Are you interested in a bachelor or master thesis that might have interesting implications for forest management? Then this project might be interesting for you.

 


Comparing growth performance of beech saplings originating form different regions of Europe

 

-topic already assigned-

Plants are genetically adapted to the climate at the place where they grow. From a widespread species like Fagus sylvatica (European beech) one would expect that different ecotypes developed in different regions of Europe. If climate is now getting warmer and dryer, ecotypes from drier regions might perform better than autochthon ecotypes. For forest management, it can be of particular interest to know which ecotypes grow best under a changing climate.

Methods:

We planted beech seedlings originating from different regions in Europe into the forest near Hanshagen following a randomized block design. After establishment in 2020 they are now ready for comparing the growth performance of the different provenances (ecotypes). To do so, height and stem diameter of the seedlings will be measured two times: first before leaf out in spring 2022 and then again in early spring 2023 (winter 2022/2023 would also be possible).

Are you a third semester student and want to start already now with your bachelor thesis, so that you have half of the data already collected before it becomes time? Do you like to work in the forest? Are you interested in a bachelor thesis that might have interesting implications for forest management? Then this project might be interesting for you.


Intraspecific variability in frost hardiness of Fagus sylvatica (BA/MA)

Time schedule:November/December 2021 to spring 2022.

Contact:

Niels Preuk (niels.preukuni-greifswaldde)
Alessandro Di Fabio (alessandro.difabiouni-greifswaldde)
Prof. Dr. Juergen Kreyling (juergen.kreylinguni-greifswaldde)

 

Background:

Frost hardiness in winter and spring influences range limits of Fagus sylvatica as well as determining its growth performance during the growing season. Recent studies showed high intraspecific variation in frost hardiness within and across populations in its distribution range, but it is still uncertain to what extent phenotypic variation arises from local adaptation. To better understand the phenotypic variation in frost hardiness, it is mandatory to consider the interplay of genotype and environment on the expression of the phenotypic trait in the population. The aim is to test for differences in frost hardiness between provenances and effects of local adaptation.

Methods:

Frost hardiness will be quantified in January/February 2022 after an initial acclimation period of Fagus sylvatica individuals under natural conditions. Plant material will be sampled from young trees at the common garden experiment near Hanshagen. Differential thermal analysis (DTA) or electrolyte leakage will be used to assess the frost hardiness of the plant material. The intraspecific variability of frost hardiness is then compared between provenances. Further, it is tested, if the frost hardiness relates to the climate at the provenance.

Literature:

Hofmann, M., Durka, W., Liesebach, M., & Bruelheide, H. (2015). Intraspecific variability in frost hardiness of Fagus sylvatica L. European Journal of Forest Research, 134(3), 433-441. https://doi.org/10.1007/s10342-015-0862-6

Wisniewski, M., Nassuth, A., & Arora, R. (2018). Cold Hardiness in Trees: A Mini-Review. Front Plant Sci, 9, 1394. https://doi.org/10.3389/fpls.2018.01394


Effect of occurrence partitioning on model performance of SDMs (BA/MA)

-topic already assigned-

 

Background and scientific question:

Species distribution models are frequently used to project range shifts of forest tree species under climate change. Many SDMs, however, do not include genetic adaptation and phenotypic plasticity, which are important mechanisms of tree species in response to changing climate and environmental factors. Local adaptation to novel conditions is often driven by intraspecific variability, particularly in long-lived species, where the input of de novo mutations is to some extent constrained. Thus, accounting for intraspecific variability in phenotypic responses can lead to a more complete representation of the fundamental niche of a species and therefore considerable improvement of the projections. Despite their frequent use, SDMs have some limitations due to different model assumptions. The aim of this project is to evaluate the effect that accounting for intraspecific variation in a long-lived species have in inferring its distribution.

Methods:

Various species distribution models will be created in the statistical computation program R and RStudio. This includes several crucial steps of species distribution modelling: (1) data search, (2) data preparation, (3) choosing the algorithm, (4) model parametrization and (5) model evaluation. Data on species occurrences and climate variables will be derived from different databases. One or several species of interest still must be determined, but most presumably it will focus on tree species. Based on the species occurrences different models will be created with different types of data partitioning. The model performances of the full occurrences model, the intraspecific occurrences model and the random partitioned occurrences model are then compared to each other.

Literature:

Dyderski, M. K., Paz, S., Frelich, L. E., & Jagodzinski, A. M. (2018). How much does climate change threaten European forest tree species distributions? Glob Chang Biol, 24(3), 1150-1163. https://doi.org/10.1111/gcb.13925

Oney, B., Reineking, B., O'Neill, G., & Kreyling, J. (2013). Intraspecific variation buffers projected climate change impacts on Pinus contorta. Ecol Evol, 3(2), 437-449. https://doi.org/10.1002/ece3.426

Valladares, F., Matesanz, S., Guilhaumon, F., Araujo, M. B., Balaguer, L., Benito-Garzon, M., Cornwell, W., Gianoli, E., van Kleunen, M., Naya, D. E., Nicotra, A. B., Poorter, H., & Zavala, M. A. (2014). The effects of phenotypic plasticity and local adaptation on forecasts of species range shifts under climate change. Ecol Lett, 17(11), 1351-1364. https://doi.org/10.1111/ele.12348


On the effect of (epi)genetic regulations on phenotypic responses. A theoretical simulation model

picture from van der Burg et al 2021 https://www.sciencedirect.com/science/article/abs/pii/S0959437X21000307

Time: flexible

Contact: Daniel Romero Mujalli, daniel.mujalli@uni-greifswald.de

 

Research questions:

  • Can regulatory mechanisms acting on a finite genome explain the limits of phenotypic plasticity?
  • Is plasticity (incl. non-neural organisms) to some extent, the result of a learning process?

Background:

Plasticity is found in all domains of life and has been thought to play an important role in evolution. However, this idea has remained controversial, particularly because of difficulties in identifying associated molecular mechanisms (Sommer 2020, Genetics 215:1). This study seeks to contribute to this topic in proposing regulatory (epi)genetic mechanisms (Angers et al. 2020, Evol. Appl 13), that can produce phenotypic plasticity, explain its limits, and, in certain scenarios, enable learning at a microscale.

Methods:

In this project, we will use R to represent the proposed molecular mechanisms leading to plastic phenotypic responses, and to explain how limits of plasticity may arise. Then, we will use an evolutionary model in Netlogo to investigate, if such a mechanism can evolve.

Learning outcomes:

The Student will

  • learn programming skills using R
  •  get familiar with the use of simulation models
  •  apply critical thinking and reasoning to the study case, as well as the imagination to depict and transmit novel ideas

Transplantations of threatened charophytes

 

Time: summer (to autumn) of 2022

Location: Sweden, regions and sites are not fixed yet

Contact: Irmgard Blindow (blindiuni-greifswaldde)

pictures: Transplantations of the rare charophyte Nitella hyalina in Switzerland. Photos by A. Schwarzer. From Blindow et al. (2021), see https://www.mdpi.com/2223-7747/10/9/1830/pdf

 

Several species of stoneworts (charophytes) are threatened in Sweden and restricted to just a few sites inspite of a high number of sites that seem “suitable”. Most probably, these species do not re-establish because oospores are lacking in the lake sediments.

Swedish authorities therefore plan to re-establish such species by means of transplantations from other sites. Methods for transplantations will be tested first by means of transplantations within existing sites before transferring plants to other sites. For rare species (with small biomasses in the present sites) pre-cultures may be necessary. Travel costs and accomodation in Sweden will be paid.

The project offers the opportunity for one, eventually several, bachelor- or master theses.


Development of a cattail cultivation on an 8-hectare experimental field in the second year after establishment (BA or MA)

Time: April to September 2021 (field work from June/July)
Location: Experimental field near Neukalen
Contact: Josephine Neubert (josephine.neubertuni-greifswaldde)

To reduce greenhouse gas emissions, soil degradation and soil subsidence of drained peatlands, rewetting of these sites is urgently needed. An important question for farmers and society is how to keep these areas productive - especially for Mecklenburg-Western Pomerania, rich in fen sites. Paludiculture, as the productive use of wet and rewetted peatlands for example with the cultivation of suitable plants, is a promising solution.

Near Neukalen, a cattail (Typha latifolia and Typha angustifolia) field of approx. 8 ha was established in 2019, to investigate the cultivation of large-scale paludiculture on a rewetted peatland. Here, the project Paludi-PRIMA (“Putting paludiculture into practice: Integration – Management – Cultivation) aims to answer questions about e.g. the feasibility, economy, and biomass quality of cattail paludiculture.

Methods: In the first vegetation period last year, 80 plots were already established and a vegetation survey took place. In this vegetation period we want to observe how the target species, as well as its accompanying vegetation develops in the second year by assessing e.g. plant height, species composition and plant cover. Furthermore, we want to identify which influence environmental factors, such as the water table, can have. Data for the thesis will be collected during several days of field work on the experimental field near Neukalen. To be able to drive to the field independently, it is an advantage to have a driver’s licence.


How beneficial is it for a tree to flush early in spring? How fast can trees adapt their phenology to changing climate conditions? (2 BA or MA)

-topic already assigned-

 

Is it an advantage for a tree to flush early in spring? Or is it too risky? We are planning two experiments to compare growth performance and survival of early and late flushing beech tree seedlings. In particular in the light of increasing summer drought, we hypothesis that early flushing tree individuals would grow better, as long as there is now late frost. Consequently, the environmental conditions during juvenile growth will drive the phenological traits of the population in one or the other direction.

Methods:

We are going to plant the seedlings in competition to each other into mesocosm (bigger boxes) and / or smaller pots. In spring, we record the leaf out day of every seedling and apply a late frost simulation for a part of the seedlings. In summer we are going to simulate different soil moisture conditions. At the end of the growing season, the increase in length and stem thickness will be determined.


Peat dynamics in vegetated and unvegetated mesocosms (BA)

Time: May to August 2022

Location: Arboretum Greifswald

Contact: Jürgen Kreyling and Kerstin Haldan

Drainage of fen soils leads to increased greenhouse gas emissions as well as soil degradation and subsidence. In an attempt to counteract these negative effects, such sites are rewetted.

After rewetting, one of the main goals is to preserve the peat layer and enable accumulation of new peat. It is well known that roots or leaves of plants can form new peat, but can vegetation also have indirect effects on peat dynamics?

In a previous experiment we found less peat loss in mesocosms with vegetation compared to those without even within one growing season. However, the reasons for this finding remain unclear and can be investigated within the framework of this thesis.

Methods: We are going to set up an experiment with peat-filled mesocosms some of which are planted with reed (Phragmites australis). To assess peat dynamics, the peat in the mesocosms is weighed before and after the experiment. Factors which can influence peat dynamics, such as soil temperature, will be monitored during the experiment.

 


Intraspecies Variation in autumn leaf colouration an spring leaf out and it´s relations to tree growth. (2 BA or MA)

Time of data collections: August- November 2022, April-Juni 2023

Location: Greifswald

Contact: Ilka Beil und Jürgen Kreyling

Trees of the same species show individual differences in their phenology, in autumn as well as in spring. Is it due to different microclimates or are there individual, genetic differences? Are early flushing individuals also early colouring? Does early flushing or late colouring enable the tree to photosynthesis longer, grow better and store more resources for next year´s leaf out?

Methods:

Autumn colouration and spring leaf out will be observed on Beech seedlings from early and late flushing mother trees. The phenological traits will be compared to the growth performance in spring. We aim to better understand adaptation of tree´s phenology to local climate conditions.


Identifizierung und Beprobung von Dachreetbeständen in Norddeutschland (BA oder MA)

Zeitraum: ab Oktober 2021 (Probennahme Januar/Februar 2022)
Ort: Greifswald (Flächen in MV, NI und SH)
Kontakt: Nora Köhn (nora.koehn@uni-greifswald.de) und Sabine Wichmann (wichmann@uni-greifswald.de)
 

Hintergrundinformationen:
Die Reetdachdeckerei ist ein uraltes Handwerk (Immaterielles UNESCO Kulturerbe) mit hoher regionaler Bedeutung an den Küsten Norddeutschlands und in seenreichen Gebieten. Den Bedarf an Qualitätsschilf als Dachreet zeigt die derzeitige Marktlage, gleichzeitig ist die Ernte von Dachreet in Deutschland seit Jahrzehnten stark rückläufig und die Importrate liegt mittlerweile bei ca. 85 %. Die Gründe sind zum einen der Verlust von Röhrichten (Schilfgürtel) durch Deichbau, Entwässerung und Kultivierung von Feuchtgebieten und zum anderen ist die traditionelle Wintermahd der verbliebenen Gebiete durch Naturschutz-Vorgaben stark eingeschränkt.
In Deutschland sind Qualitätskriterien für Reet als Dachdeckmaterial über die Fachregeln der Dachdeckung geregelt. Hier werden Maße, Anforderungen und Prüfungen beschrieben. Meistens beruht die individuelle Qualitätseinschätzung aber maßgeblich auf generationsübergreifenden Erfahrungen der verarbeitenden Betriebe. Die Eingrenzung und Vereinheitlichung der Qualitätsanforderungen können noch verbessert und die Erfahrungen der Handwerker (Rohrwerber und Reetdachdecker) müssen mit Literaturangaben verbunden werden. Insbesondere sind qualitätsbestimmende Standortfaktoren bzw. Wachstumsbedingungen zu identifizieren, um Empfehlungen für die Kultivierung von Schilf abzuleiten.
Methoden:
Die Durchführung der Abschlussarbeit soll sich in mehrere theoretische und praktische Teile aufgliedern, deren Ergebnisse im Anschluss sinnbringend in einer schriftlichen Ausarbeitung zusammengeführt werden müssen.

  • Herbst 2021 (theoretische Vorarbeit):

Recherche zu Qualitätsanforderungen und Untersuchungsparametern, Anfrage und Befragungen von Rohrwerbern/Reetdachdeckern, Identifizierung von Flächen in Mecklenburg-Vorpommern, Niedersachsen und Schleswig-Holstein

  •  Herbst/Winter 2021 (praktische Vorarbeit):

Standortbesichtigung und Voruntersuchung (Begleitvegetation, Stratigrafie, etc.)

  • Winter 2022 (praktische Durchführung):

Probennahme auf den Flächen, Probenbearbeitung hinsichtlich der recherchierten/bekannten Qualitäts-
anforderungen, Datenanalyse


Assessing peat formation in rewetted fens – comparing wilderness and paludiculture in the Netherlands, Germany and Poland (BA/MA)

Data collection: Autumn 2022
Location: Germany, the Netherlands, Poland
Contact: Dr. Franziska Tanneberger, Dr. Elke Seeber

Background: Within our EU project PRINCESS, we collaborate with partners in Belgium, Poland, Austria, Norway and Finland to better understand peat formation in rewetted fen peatlands under different nutrient loads and under different land use (wilderness vs. paludiculture). In fens, peatland is largely formed by roots, so assessing root production and root decomposition is crucial to study. This helps us to assess the peat formation potential of a specific site. Project website: https://www.moorwissen.de/en/moore/tools/projekte/princess/princess.php

Methods: In autumn 2021, we have installed ingrowth cores of 50 cm length filled with root-free peat in all study sites. The will be retrieved in autumn 2022 and the roots within the cores will be washed out, dried and weighted. We have also installed litter bag frames of 50 cm depth including litter bags filled with local root material and standard tea bags. They will also be retrieved in autumn 2020, cleaned and weighted. Students are invited to get involved and contribute to field work, lab work as well as data analysis and interpretation!


Root phenology of wetland plants in response to water regime (1 MA or 2 BA)

Timing: second half of 2022
Contact: Bo Peters & Jürgen Kreyling
Location: Greifswald

Plant roots play key roles in ecosystem function and are of special importance in fens, where roots and rhizomes form peat and thus are the main contributors to large carbon stores. However, little is known about the root dynamics of different species, how they respond to changes in water table height, and how species respond to competition. This project is within the framework of WETSCAPES (www.wetscapes.uni-rostock.de).

Methods: Using minirhizotrons (root cameras) in a mesocosm facility to assess root growth and root architecture in fen species originating under different water table regimes.


Root dynamics in drained and rewetted peatlands in the face of climate change (MA or 2 BA)

Timing: second half of 2022
Contact: Bo Peters & Jürgen Kreyling
Location: Greifswald

Peatlands are globally important carbon sinks, but drainage of peatlands leads to a release of the stored carbon and to large emission of greenhouse gases. To reduce greenhouse gas emissions, efforts are made in rewetting these systems in the hope of restoring their potential as carbon stores.

Here, the root growth dynamics in three different types of drained and rewetted peatlands (alder carr, percolation mire and coastal mire) are assessed by the minirhozotron technique. The same observations occurred already in the extremely dry and warm years 2018 and 2019 and 2020, when water tables even in the rewetted fens dropped below -60 cm. According to the IPCC report (2013), these extreme weather conditions are projected to increase with climate change. Long-term observations of root dynamics in drained and rewetted peatlands will increase our knowledge on how these ecosystems might react to changes in climate and if they are able to maintain their important function as carbon sinks in the future. This project is within the framework of WETSCAPES (www.wetscapes.uni-rostock.de).

Methods: Using minirhizotrons (root cameras), root growth in space and time is analysed at drained and rewetted peatlands in MV, which will be visited monthly during the growing season. A driving license is needed and an own car is a merit (travel costs will be covered).


Reindeer grazing and snow effects on plant communities and ecosystem carbon balance in a boreal fen (1 or 2 MA)

Timing: Winter/Spring 2022 or summer 2022

Contact: Gesche Blume-Werry (gesche.blume-werry@umu.se)

Location: Oulanka, northern Finland

Climate change is shifting the duration and thickness of snow cover in boreal regions. At the same time, large herbivores, reindeer, are key drivers of plant community dynamics as they influence plant productivity directly through defoliation and the return of nutrients, but also induce changes in soil processes.  The EcoClimate experiment in northern Finland aims to find out how ecosystems respond to these two factors (reindeer grazing and snow cover changes).

We are now looking for a student to test how winter climate and reindeer grazing affect plant communities and ecosystem carbon balance (plant community composition, root growth, trace gas fluxes fluxes, and biogeochemistry). You would stay at the Oulanka Research Station in northern Finland for several (4-8) weeks. We support you with application for travel funding, for example with Erasmus.

Methods: Pin-pointing, minirhizotrons (root cameras), and gas flux chamber measurements. Prior knowledge of some of these methods is a merit, but not essential.


Recovery of a coastal heathland after disturbance - does drought matter? (BA or MA)

-Thema vergeben-

Coastal heathlands are dominated by Calluna vulgaris. They are old cultural landscapes of high conservation value. However, atmospheric nitrogen deposition and management cessation have led to increased competition by grasses and woody species, thereby endangering this ecosystem type. In a field experiment on the island of Hiddensee, we test if climate change-induced drought would further exacerbate these developments and if (simulated) sheep grazing might retard it. All this is realized in two successional stages, one with young and vigorously-growing Calluna plants and the other with over-aged and partly dying Calluna. The whole experiment is part of the International Drought Experiment (https://wp.natsci.colostate.edu/droughtnet/) , a network which runs comparable drought experiments all over the globe.

Methods: The experiment is running since 2015. Here, aboveground biomass of all species is to be quantified via non-destructive measures (point intercept method). Belowground biomass will
be studied for the first time in this experiment by destructive samples. One visit to Hiddensee is  required, lasting for 4-5 days. Travel costs are paid.


Effects of deep-rooting vegetation and permafrost thaw on tundra carbon emissions (1 MA)

Timing: winter/spring 2022 (ideally from January onwards)

Contact: Gesche Blume-Werry (gesche.blume-werry@umu.se)

Location: Abisko, northern Sweden

Permafrost thaw and changes in vegetation can lead to large carbon emissions from arctic tundra, potentially also during winter. The overall objective of this project is to find out how much CO2 plants and microbes respire in winter versus summer, and how this is affected by permafrost thaw and associated vegetation changes. It’s already ongoing (since August), and the design is: vegetation with (deep-rooting) Eriophorum vs. vegetation without Eriophorum x intact active layer vs. deep active layer. For each of these 4 treatments, there is a flux ring with vegetation and one where the aboveground vegetation is clipped, to be able to partition the total CO2 respiration flux into the microbial (heterotrophic) part and the plant-related part.

Measurements are being taken until December, and we are looking for a student but to continue measuring the fluxes or analyse and write-up (all) the data. Within the thesis there is lots of possibility to focus on different aspects of the treatments or of seasonality. We would support you with application for travel funding, for example with Erasmus.

Methods: gas flux chamber measurements, prior knowledge of this is a merit, but not essential.


Assessing biodiversity in rewetted fens – comparing wilderness and paludiculture in Germany (BA/MA)

Data collection: Spring-Autumn 2022
Location: Germany (rewetted peatlands around Lake Kummerower See, M-V)
Contact: Dr. Franziska Tanneberger, Dr. Peter Michalik

Background: Within our EU project PRINCESS, we study rewetted fen peatlands under different nutrient loads and under different land use (wilderness vs. paludiculture). To assess biodiversity, along with floristic diversity, also breeding birds and arthropods are essential. Project website: https://www.moorwissen.de/en/moore/tools/projekte/princess/princess.php

Methods: In 2021, we studied plants, breeding birds and various groups of arthropods (spiders, ground beetles, grasshoppers, dragonflies) on the 6 study plots in Germany. We plan to continue the study in 2022. Students are invited to get involved and contribute to field work, lab work as well as data analysis and interpretation!


Forest ecosystem functioning in response to warmer and wetter winters (MA or BA)

Time: fieldwork in January AND/ Or in March AND/ OR in June

Location: beech forests between Rostock (Germany) and Gdansk (Poland)

Contact: Aron Garthen, Jürgen Kreyling

 

Winter climate is changing towards warmer and wetter conditions. The net effects on soil temperatures are unclear and differ among regions, mainly depending on the occurrence of an insulating snow cover. In regions with little snow pack, soils will get warmer, what enhances nutrient release. Increased nutrient availability will either result in increased plant growth or, if winter precipitation increases, in increased nutrient leaching. In regions with high snowfall, however, the loss of an insulation snow cover may result in colder soils and reduced nutrient availability.

In this context, the importance of winter precipitation for the ecology and biogeochemistry of temperate beech forests will be investigated to get a better understanding of how these ecosystems will respond to climate change.

 

Methods

The investigations are carried out in a field experiment along a large climatic gradient with nine experimental sites between Rostock (Germany) and Gdansk (Poland). Experimental manipulations of our target trees will consist of (A) winter rain addition and (B) winter rain addition in absence of snow cover.

The project offers the opportunity forseveral Bachelor’s or Master’s theses. Possible topics would be

  • decomposition rates (tea bag method),
  • soil biotic activity,
  • nutrient availability and leaching,
  • phenological investigations regarding the start of the growing season,
  • root growth,

or a combination of those.

You will join at least one round trip to the experimental sites during winter or in spring.   

 


Heritability of frost hardiness in Fagus sylvatica

-topic already assigned-

Background:

Frost hardiness in winter and spring influences range limits of Fagus sylvatica as well as determining its growth performance during the growing season. Recent studies showed high intraspecific variation in frost hardiness within and across populations in its distribution range, but it is still uncertain to what extent phenotypic variation arises from local adaptation and weather frost tolerant mother trees produce frost tolerant offspring. Determining trait heritability, i.e., the proportion of variance that is due to genetic factors as opposed to environmental influences, will give a better understanding of the phenotypic variation.

Methods:

Frost hardiness will be quantified in between November 2021 and March 2022. Plant material will be sampled from mother trees and their respective offspring in the Serrahn beech forest in the Müritz Nationalpark. Young trees, grown from seed of specific mother trees will be brought to the mother trees in early fall to acclimate under the same conditions before the frost tolerance tests. Differential thermal analysis (DTA) will be used to assess the frost hardiness of the plant material. In this method, plant material equipped with temperature sensors is placed in cooling chambers to record freezing episodes in plant tissue under decreasing temperature. The data on parental and progeny frost hardiness can be used to determine the trait heritability within the population.

Literature:

Hofmann, M., Durka, W., Liesebach, M., & Bruelheide, H. (2015). Intraspecific variability in frost hardiness of Fagus sylvatica L. European Journal of Forest Research, 134(3), 433-441. https://doi.org/10.1007/s10342-015-0862-6

Wisniewski, M., Nassuth, A., & Arora, R. (2018). Cold Hardiness in Trees: A Mini-Review. Front Plant Sci, 9, 1394. https://doi.org/10.3389/fpls.2018.01394


Heathland vegetation on Hiddensee island

Flowering heather (Calluna vulgaris) in the coastal dune heathlands on the island of Hiddensee. Photo Irmgard Blindow

-topic already assigned-

 

Different management measures (mowing, choppering, sod-cutting) have been applied in the coastal dune areas on the island of Hiddensee to promote and rejuvenate the typical heathland vegetation. The development of this vegetation is investigated on a number of permanent plots. Another investigation shall be repeated during 2022 and analysed in comparison with former years.

 

The project offers the opportunity for one bachelor thesis. Best period for field work is June to September. Travel costs and accomodation at the Biological Station will be paid / provided. Detailed knowledge in plant determination (flowering plants) is mandatory. Knowledge in determination of mosses and lichens is optional. Further information: Blindow, I., Gauger, D., Alhaus, M. 2017. Management regimes in a coastal heathland – effects on vegetation, nutrient balance, biodiversity and gain of bioenergy. Journal of Coastal Conservation 21(2): 273–288. DOI: 10.1007/s11852-017-0499-3


Forest trees phenotypic plasticity in response to climate change (BA/MA)

Time schedule:
Between Mid-February and mid-April 2022

Contacts:
Alessandro Di Fabio (alessandro.difabio@uni-greifswald.de)
Prof. Dr. Jürgen Kreyling (juergen.kreyling@uni-greifswald.de)

Background:
Climate change is already impacting important forest tree species. As long-lived tree species cannot shift their distribution ranges quickly, local adaptation to changing climatic conditions will play a significant role in the future of European forests.

Phenology (the timing of leaf growth and fall) plays an important part in the adaptation to the local climatic condition for trees. The timing of leaf flushing is given by the balance between earlier bud-burst and the danger of a late spring frost.

At the same time, leaves are the organ though which trees photosynthesize and transpire water, and for this reason plants strike a balance in leaf size: bigger leaves means more sunlight is captured, but smaller leaves with thicker cuticles and fewer stomata help retain water in drought conditions.

Aims:
The aim of this project is to understand how different ecotypes of various tree species react to the local climatic conditions, for instance by flushing leaves earlier or growing smaller ones. These insights will then be correlated with the growth performance of the trees, in order to investigate the interplay of phenotypic adaptation, climatic conditions, and genetics.

This research is part of the EVA project (Evidence-based cultivation recommendations in climate change), and will provide important insights on the potential for valuable tree species to adapt to climate change via phenotypic plasticity.

Methods:
Phenology will be measured by installing cameras at the trial locations in Austria and Germany before spring. At the same time, data loggers for temperature and humidity will be placed in the soil and in the tree canopy, to characterize the climatic conditions at the sites. Twig samples will be collected to measure the buds’ physical and physiological characteristics.

Literature:
Capdevielle-Vargas, R., Estrella, N. & Menzel, A. Multiple-year assessment of phenological plasticity within a beech (Fagus sylvatica L.) stand in southern Germany. Agricultural and Forest Meteorology 211–212, 13–22 (2015). https://doi.org/10.1016/j.agrformet.2015.03.019

Bresson, C. C., Vitasse, Y., Kremer, A. & Delzon, S. To what extent is altitudinal variation of functional traits driven by genetic adaptation in European oak and beech? Tree Physiology 31, 1164–1174 (2011). https://doi.org/10.1093/treephys/tpr084


Understanding plants phenology by digging into bid data - MA

Time: flexible
Location: flexible
Contact: Ilka Beil

For ecological research, there is a huge potential in the use comprehensive and still growing data bases. In Europe we have a great database on phenological observations over the last decades, the Pan European Phenology Project PEP725 (http://www.pep725.eu/). Using this date can tell us for instance, that with climate warming forest trees flushing happened earlier and earlier. But we can investigate this topic much more in detail: Is it the rising minimum winter temperature, which advances spring bud burst? Or is it the shortening of the cold season, i.e. the late onset of cool temperatures in autumn? Leaf unfolding is advances, but how about earlier stages of flushing, like the swelling or opening of the buds? Investigating existing observational data in depth can help us a lot to understand the response of plants and ecosystems to the environment, for instance with regard to their frost risk. - A master thesis for someone who likes to work with big data and R.


Laufende und abgeschlossene Abschlussarbeiten:

2022

2022

Auswirkungen von Trockenstress auf das Wachstum von Phragmites australis zweier verschiedener Ploidiestufen
(Masterarbeit betreut von Kerstin Haldan und Jürgen Kreyling)

Generationsübergreifende individuelle Unterschiede in der Phänologie bei Fagus sylvatice (L.)
(Bachelorarbeit betreut von Ilka Beil und Jürgen Kreyling)

2021

2021

Paludikultur trotz Trockenheit? - Reaktion unterirdischer Biomasse von polyploiden Schilfklonen auf einen Dürregradienten
(B.Sc. Arbeit, btreut durch Jürgen Kreyling und Kerstin Haldan)

Predicting biomass production of Typha spec. on a rewetted paludiculture site over time using multitemporal and multispectral UAV data
(M.Sc. Arbeit, betreut durch Jürgen Kreyling und Sebastian van der Linden)

Auswirkungen von Renaturierung auf die unterirdische Biomassebildung in Niedermooren
(B.Sc. Arbeit, betreut durch Jürgen Kreyling und Sarah Schwieger)

Das Wurzelwachstum von Moopflanzen im Frühjahr unter Einfluss verschiedener Wasserstände
(B.Sc.-Arbeit, betreut durch Jürgen Kreyling und Bo Peters)

Effects of drought on the growth of tera- and octoploid clones of Phragmites australis in a gradient experiment
(B.Sc.-Arbeit, betreut durch Jürgen Kreyling & Kerstin Haldan)

Einfluss der Schneebedeckung auf die Frosthärte von Vaccinium myrtillus und Vaccinium vitisidaea
(B.Sc.-Arbeit, betreut durch Jürgen Kreyling)

Dürresimulation in der Küstenheide - Ermittlung der Ursachen für das Ausbleiben eines Dürreeffekts auf Heidepflanzen
(B.Sc.-Arbeit, betreut durch Jürgen Kreyling & Irmgard Blindow)

Die Quantifizierung von Wurzelexudaten und der Link zu ober- und unterirdischer Aktivität von Niedermoorpflanzen
(M.Sc.-Arbeit, betreut durch Jürgen Kreyling & Nicole Wrage-Mönnig)

Individuelle Unterschiede in der Frühjahrsphänologie und deren Vererbbarkeit bei Fagus sylvativa (L.)
(B.Sc.-Arbeit, betreut durch Jürgen Kreyling & Jonas Schmeddes)

Autumnal root phenology of wetland plants under different water regimes
(B.Sc.-Arbeit, betreut durch Jürgen Kreyling & Bo Peters)

Influence of Vegetation COver and Mychorrizal Types on Litter Decomposition in Arctic Heath Vegetation Soil. A Tea Bag Study.
(B.Sc.-Arbeit, betreut durch Gesche Blume-Werry & Konstantin Gavazov)

Comparing decomposition in drained and rewetted peatlands: the effect of depth, fen ecosystem and litter type
(M.Sc.-Arbeit, betreut durch Gesche Blume-Werry & Sarah Schwieger)

Autumn phenology of roots in temperate fens
(M.Sc.-Arbeit, betreut durch Jürgen Kreyling & Bo Peters)

2020

2020

Drought tolerance of tetra- and octoploid clones of Phragmites australis in a gradient experiment
(M.Sc.-Arbeit, betreut durch Jürgen Kreyling und Kerstin Haldan)

The ecological role of microbes in the digestive process of Nepenthes hemsleyana & N. rafflesiana
(M.Sc.-Arbeit, betreut durch Michael Schöner und Jürgen Kreyling)

Impacts of environmental factors and cultivation parameters on the establishment of Typha latifolia and T. angustifolia at a paludiculture site
(M.Sc.-Arbeit, betreut durch Josephine Neubert und Jürgen Kreyling)

Wasser, Konkurrenz und Temperatur als Treiber für ober- und unterirdisches Wachstum von Moorpflanzen im Frühling
(B.Sc.-Arbeit, betreut durch Jürgen Kreyling und Gesche Blume-Werry)

Root phenology on three different fen types in drained and rewetted conditions
(M.Sc.-Arbeit, betreut durch Jürgen Kreyling und Sarah Schwieger)

Kurzfristige Wurzelwachstumsdynamik in täglicher Auflösung bei varriierenden Wasserständen in Niedermooren
(B.Sc.-Arbeit, betreut durch Jürgen Kreyling und Gesche Blume-Werry)

Das Wachstum der unterirdischen Biomasse der Rohrkolbenarten Typha latifolia und Typha angustifolia entlang von Gradienten der Nährstoffverfügbarkeit und des Wasserstandes
(B.Sc.-Arbeit, betreut durch Kerstin Haldan und Jürgen Kreyling)

Are phenological leaf traits of mother trees and their offsprings' timing of germination correlated in Fagus sylvatica?
(B.Sc.- Arbeit, betreut durch Jürgen Kreyling und Jonas Schmeddes)

Wurzel- und Rhizomwachstum verschiedener Genotypen von Phragmites australis entlang eines Wasserstandsgradienten
(B.Sc.-Arbeit, betreut durch Jürgen Kreyling und Kerstin Haldan)

Wie tief schlafen Bäume wirklich? - Verlauf der Wurzeldormanz im Vergleich zur Knospendormanz
(B.Sc. Arbeit, betreut durch Andrey Malyshev und Gesche Blume-Werry)

Root porosities of Phragmites australis clones differ along artificial water and nutrient gradients
(M.Sc. Arbeit, betreut durch Jürgen Kreyling und Kerstin Haldan)

Die specific root length (SRL) von Phragmites australis entlang eines Nährstoffgradienten in einem Mesokosmenexperiment
(B.Sc. Arbeit, betreut durch Kerstin Haldan und Jürgen Kreyling)

The effect of frost on the photosynthetic activity of winter reapeseed (Brassica napus) during a mild winter
(B.Sc. Arbeit, betreut durch Ilka Beil und Jürgen Kreyling)

Specific Root Length variation of Phragmites australis clones in response to different water levels
(B.Sc. Arbeit, betreut durch Jürgen Kreyling und Kerstin Haldan)

Frühjahrsphänologie von Fagus sylvatica L. unter Dürrebedingungen und unter Betrachtung verschiedener Herkünfte
(B.Sc. Arbeit, betreut durch Ilka Beil und Andrey Malyshev)

Trockenheitsschäden an Calluna vulgaris und deren Erholung in der Küstendünenheide von Hiddensee, erfasst durch wiederholte Drohnenbefliegung
(B.Sc. Arbeit, betreut durch Jürgen Kreyling und Tobias Dahms)

Quantifying phenotypic plasticity of Fagus sylvatica in a reciprocal transplantation experiment across a Europe-wide gradient
(M.Sc. Arbeit, betreut durch Jürgen Kreyling und Jonas Schmeddes)

Untersuchungen über die Auswirkungen verschiedener Wasserlevel und Nährstofflevel auf das Blatt- und Sprosswachstum bei fünf verschiedenen Klonen von Phragmites australis
(B.Sc. Arbeit, betreut durch Jürgen Kreyling und Kerstin Haldan)

Die Brutvögel des Strandwallfächers auf de Insel Hiddensee
(BSc-Arbeit, Betreuer: Irmgard Blindow & Angela Schmitz-Ornes)

Untersuchungen zu Beziehungen zwischen höheren Pflanzen und Standortfaktoren im Strandwallfächer und auf der Glambäkwiese auf de Insel Hiddensee
(BSc-Arbeit, Betreuer: Irmgard Blindow & Heike Ringel)

Brutvögel im Dornbusch auf der Insel Hiddensee - Zusammenhang mit zunehmender Verbuschung
(BSc-Arbeit, Betreuer: Angela Schmitz & Irmgard Blindow)

Die Grabwespenfauna der Insel Hiddensee - Veränderungen über fünf Jahrzehnte
(BSc-Arbeit, Betreuer: Irmgard Blindow & Christian Schmid-Egger)

Recovery of a coastal heathland after disturbance – does drought matter?
(BSc-Arbeit, Betreuer: Jürgen Kreyling  und Ilka Beil)

2019

2019

Zusammenhang von Frostresistenz und Zeitpunkt des Austriebs bei Gehöölzen im Greifswalder Arboretum
(B.Sc.-Arbeit, betreut durch Ilka Beil und Jürgen Kreyling)

Photosynthesis rates in five clones of Phragmites australis in a water and a nutrient gradient experiment
(M.Sc.-Arbeit, betreut durch Jürgen Kreyling und Kerstin Haldan)

Importance of snow cover for understory plants in boreal forests
(B.Sc.-Arbeit, betreut durch Jürgen Kreyling und Gesche Blume-Werry)

Einfluss der Temperatur auf die Dormanztiefe und Frühlingsphänologie bei vier verschiedenen Laubbaumarten
(B.Sc.-Arbeit, betreut durch Jürgen Kreyling und Ilka Beil)

Development of root distribution patterns of Andean Lupin (Lupinus mutabilis) in monoculture and intercropped with maize
(M.Sc.-Arbeit, betreut durch Jürgen Kreyling und Herr Dr. Böhm)

Effects of snow cover on fine root growth in beech forest varying in winter harshness
(B.Sc.-Arbeit, betreut durch Robert Weigel und Juergen Kreyling)

Putting the root growth of an extreme year into perspective
(M.Sc.-Arbeit, betreut durch Gesche Blume-Werry und Sarah Schwieger)

Digital visualization of roots in peat
(M.Sc.-Arbeit, betreut durch John Couwenberg und Gesche Blume-Werry)

Comparison of root growth within and among five Carex species, influenced by nutrient levels
(M.Sc.-Arbeit, betreut durch Gesche Blume-Werry und Juergen Kreyling)

Influence of water regime on root production of wetland plants
( B.Sc.-Arbeit, betreut durch Gesche Blume-Werry und Juergen Kreyling)

The influence of aspect on species composition and phenology at mountain summits of Nuolja and Slåttajakka, Sweden
(B.Sc.-Arbeit, betreut durch Gesche Blume-Werry und Keith Larsen)

Changes in vegetation composition in the last 100 years on Mount Nuolja, northern Sweden
(B.Sc.-Arbeit, betreut druch Gesche Blume-Werry und Keith Larsen)

Einflussfaktoren auf die Blühphänologie von Anemone Nemorosa
(B.Sc.-Arbeit, betreut durch Jürgen Kreyling und Jonas Schmeddes)

Zusammenhang von Baumbeschaffenheit und Zeitpunkt des Austriebs bei etwa 500 Baum- und Straucharten im Greifswalder Arboretum
(B.Sc.-Arbeit, betreut durch Jürgen Kreyling und Ilka Beil)

Assessing root production in drained and re-wetted peatlands
(B.Sc.-Arbeit, betreut durch Jürgen Kreyling und Sarah Schwieger)

Influence of temperature on autumnal phenology in trees
(B.Sc.-Arbeit, betreut durch Jürgen Kreyling und Ilka Beil)

Age and biomass distribution of Alnus glutinosa roots in a drained and a rewetted Swamp
(M.Sc.-Arbeit, betreut durch Frau Dr. Anadon-Rosell und Sarah Schwieger)

Abbau organischen Materials in trockenen und wiedervernässten Mooren
(B.Sc.-Arbeit, betreut durch Sarah Schwieger und Gesche Blume-Werry)

Einfluss der landwirtschaftlichen Nutzung auf das Vorkommen von Amphibien in Kleingewässern Rügens
(MSc-Arbeit, Betreuer: Falk Ortlieb & Irmgard Blindow)

Einfluss der landwirtschaftlichen Nutzung auf das Vorkommen von Wasserpflanzen in Kleingewässern auf Rügen
(MSc-Arbeit, Betreuer: Irmgard Blindow & Hendrik Schubert)

Der Einfluss von Makrophyten auf Makrozoobenthos in zwei flachen Küstengewässern der Ostsee
(BSc-Arbeit, Betreuer: Martin Paar & Irmgard Blindow)

Feeding behaviour of the marine gastropod Aplysia dactylomela under elevated temperatures
(MSc-Arbeit, Betreuer: Mark Lenz & Irmgard Blindow)

Einfluss unterschiedlicher Habitatqualität auf die Nahrungsökologie und den Bruterfolg des Braunkehlchens (Saxicola rubetra)
(BSc-Arbeit, Betreuer: Irmgard Blindow & Hermann Hötker)

2018

2018

Minirhizotron picture analysis - maintaining accuracy while reducing time effort
(B.Sc.-Arbeit betreut durch Gesche Blume-Werry und Robert Weigel)

Einfluss von Trockenheit und Beweidung auf die Entwicklung der Heide auf Hiddensee
(B.Sc.-Arbeit, betreut durch Ilka Beil und Jürgen Kreyling)

Management options for the conversion of non-native coniferous forest patches towards more natural species composition in the Western Pomerania Lagoon Area National Park (Germany)
(Masterarbeit, betreut durch Juergen Kreyling und Michael Manthey)

Do volcanoes fertilize the globe?
(Bachelorarbeit, betreut durch Juergen Kreyling und Ilka Beil)

Frost and drought tolerance in two provenances of a temperate weed (Anchusa arvensis)
(Bachelorarbeit, betreut durch Andrey Malyshev)

Cross-stress memory: Influence of prior frost exposure on drought tolerance of a temperate weed
(Bachelorarbeit, betreut durch Andrey Malyshev)

Variation der Frühjahrsphänologie bei Rotbuchen (Fagus sylvatica L.) unter Betrachtung der innerartlichen Konkurrenz
(Bachelorarbeit, betreut durch Juergen Kreyling & Ernst van der Maaten)

Inter-individual variation in spring phenology of european beech
(Bachelorarbeit, betreut durch Juergen Kreyling & Andrey Malyshev)

Effects of manipulated snow cover on fine root growth in beech forests varying in winter harschness
(Bachelorarbeit, betreut durch Robert Weigel & Juergen Kreyling)

Möglicher Zusammenhang zwischen Elektrolytgehalt und Tiefe der Knospendormanz
(Bachelorarbeit, betreut durch Andrey Malyshev)

Conditionally expressed heritability in Fagus sylvatica in a translocation experiment across Europe
( Masterarbeit, betreut durch Juergen Kreyling & Lena Muffler)

Chasing aliens: The effects of non-native species removal on early stages of tallgrass prairie restoration
(Bachelorarbeit, betreut durch Hugh AL Henry & Juergen Kreyling)

Stressgedächtnis und lokale Anpassung verschiedener Herkünfte der Rotbuche (Fagus sylvatica L.) an Frost
(Bachelorarbeit, betreut durch Juergen Kreyling)

Temperature dependence of heritability in Arabidopsis thaliana
(Masterarbeit, betreut durch Juergen Kreyling)

Using historical and phenological data to explain spatial and temporal variation in spring budburst dates of five tree species in Germany
(Masterarbeit, betreut durch Andrey Malyshev)

Untersuchung der Zersetzung in trockengelegten und wiedervernässten Mooren mit dem Tea Bag Index
(Bachelorarbeit, betreut durch Jürgen Kreyling & Sarah Schwieger)

Structure and migration behaviour of zooplankton in the lagoons of the southern Baltic Sea
(MSc-Arbeit, Betreuer: Irmgard Blindow, Rhena Schumann)

Nährstofflimitation des Phytoplanktons in Boddengewässern Mecklenburg-Vorpommerns
(MSc-Arbeit, Betreuer: Max Berthold, Irmgard Blindow)

Impacts of eutrophication on growth of the European perch Perca fluviatilis (Linnaeus 1758) in brackish coastal lagoons of the Baltic Sea
(MSc-Arbeit, Betreuer: Hendrik Schubert, Martin Paar)

2017

2017

Effects of snow cover on fine root growth in beech forests varying in winter harshness
(Bachelorarbeit, betreut durch Robert Weigel)

Memory effects and intraspecific variation in stress response of Fagus sylvatica to recurrent drought events
(Bachelorarbeit, betreut durch Jürgen Kreyling)

Cross-stress tolerance and stress memory in perennial plants
(Bachelorarbeit, betreut durch Andrey Malyshev)

Bud dormancy and frost tolerance in trees – are they linked?
(Masterarbeit, betreut durch Andrey Malyshev)

Die Auswirkungen verschiedener Winterbedingungen auf die Knospenzruhe und Knospenfrosthärte bei Fagus sylvatica
(Bachelorarbeit, betreut durch Jürgen Kreyling)

Root- and shoot phenology in different vegetation types
(Masterarbeit, betreut durch Gesche Blume-Werry und Juergen Kreyling)

Influence of warm temperature on growth and development of Arabidopsis thaliana
(Bachelorarbeit, betreut durch Jürgen Kreyling und Ilka Beil)

Impacts of machine mowing on selected soil properties of near-natural fens - A case study from NE Germany
(Masterarbeit, betreut durch Franziska Tanneberger und Juergen Kreyling)

Impacts of machine mowing on vegetation composition, root porosity and decomposition in near-natural fens - A case study from NE Germany
(Masterarbeit, betreut durch Elke Seeber und Juergen Kreyling)

Response of a coastal heathland to drought and grazing during different successional stages
(Bachelorarbeit, betreut durch Ilka Beil und Juergen Kreyling)

Importance of the three-spined stickleback (Gastrerosteus aculeatus) in the food web of two coastal shallow lagoons in the southern Baltic Sea
(Masterarbeit, betreut durch Irmgard Blindow)

Effects of snow cover on fine root growth in beech forests varying in winter harshness
(Bachelorarbeit, betreut durch Robert Weigel und Jürgen Kreyling)

Within-species variation in leaf traits of Fagus sylvatica in response to macroclimatic site conditions
(Bachelorarbeit, betreut durch Lena Muffler und Jürgen Kreyling)

Leaf and growth traits in different populations of Fagus sylvatica in response to drought
(Masterarbeit, betreut durch Jürgen Kreyling und Lena Muffler)

Stressgedächtnis und lokale Anpassungsfähigkeit verschiedener Herkünfte der Rotbuche (Fagus sylvatica L.) an Spätfrost
(Bachelorarbeit, betreut durch Lena Muffler und Jürgen Kreyling)

Veränderungen der Waldbodenvegetation entlang eines Temperaturgradienten in Buchenwäldern an neun Standorten in Deutschland und Polen
(Masterarbeit, betreut durch Robert Weigel und Jürgen Kreyling)

Developement of bud dormancy and cold tolerance in species with different chilling requirements
(Diplomarbeit, betreut durch Andrey Malyshev)

Comparison of above ground and below ground autumn phenology in contrasting temperate vegetation types
(Masterarbeit, betreut durch Jürgen Kreyling und Robert Weigel)

2016

2016

Bestimmung der flächendifferenzierten Grundwasserneubildung eines holozänen Porengrundwasserleiters auf Hiddensee (Mecklenbeck-Vorpommern)
(Bachelorarbeit, betreut durch Maria Schafmeister und Irmgard Blindow)

Kalkinkrustierung verschiedener Characeenarten in Süß- und Brackwasser
(Masterarbeit, betreut durch Irmgard Blindow)

Distribution of Zostera marina in the coastal waters of the Baltic Sea
(Masterarbeit, betreut durch Irmgard Blindow)

Der Einfluss meteorologischer Elemente auf das Blühverhalten ausgewählter Orchidaceae des Naturpark Schlaubetal
(Bachelorarbeit, betreut durch Jürgen Kreyling)

Influence of soil-borne pathogens on seedling performance in declining Quercus suber forests: an experimental approach
(Masterarbeit, betreut durch Jürgen Kreyling)

Temporal bud dormancy and cold tolerance changes in trees
(Bachelorarbeit, betreut durch Andrey Malyshev)

Populations-spezifische Frosttoleranz vor und nach der Keimung von Fagus sylvatica
(Bachelorarbeit, betreut durch Jürgen Kreyling und Lena Muffler)

Allometric quantification of biomass in Calluna vulgaris
(Masterarbeit, betreut durch Jürgen Kreyling und Irmgard Blindow)

Fotoidentifikation von Meeresschildkröten auf Koh Tao, Thailand
(Bachelorarbeit, betreut durch Irmgard Blindow)

2015

2015

Plant stress memory: effects of recurrent drought and frost events on stress resistance in P lanceolata
(Masterarbeit, betreut durch Andrey Malyshev)

Long term effects of a crude oil spill on desert vegetation
(Bachelorarbeit, betreut durch Jürgen Kreyling)

Effects of climate change induced autumnal warming on root phenology in the Arctic tundra
( Masterarbeit, betreut durch Jürgen Kreyling)

Zusammenhang zwischen frühlaichenden Amphibien und Habitateigenschaften von Kleingewässern auf der Insel Hiddensee
(Bachelorarbeit, betreut durch Irmgard Blindow)

Zusammenhang zwischen Gewässereigenschaften und Amphibien auf der Insel Hiddensee
(Masterarbeit, betreut durch Irmgard Blindow)

Beziehungen zwischen Zooplankton und submersen Makrophyten in der Darß-Zingster Boddenkette
(Masterarbeit, betreut durch Irmgard Blindow)

Sedimentation und Resuspension in der Darß-Zingster Boddenkette – eine Methodenstudie
(Masterarbeit, betreut durch Irmgard Blindow)

Composition and adaptation of submerged macrophytes in shallow coastal lagoons of the southern Baltic Sea
(Masterarbeit, betreut durch Irmgard Blindow)

2014

2014

Interaktionen zwischen suspendiertem Material und submersen Makrophyten in flachen Küstengewässern der südlichen und westlichen Ostsee
(Diplomarbeit, betreut durch Irmgard Blindow)

Zusammenhang zwischen Makrophytobenthos und Sedimentstruktur in flachen Küstengewässern der deutschen Ostsee
(Diplomarbeit, betreut durch Irmgard Blindow)

Wechselwirkungen zwischen Phytoplankton, Nährstoffen und Submersvegetation an der deutschen Ostseeküste
(Diplomarbeit, betreut durch Irmgard Blindow)

Interaktionen zwischen Zooplankton und submersen Makrophyten in den Boddengewässern vor Hiddensee
(Diplomarbeit, betreut durch Irmgard Blindow)

Potential und aktueller Stand der Kultivierung von Dreissena polymorpha zur Verbesserung des ökologischen Zustandes des Usedomer Sees
(Masterarbeit, betreut durch Sven Dahlke)

Aktuelle Situation submeser Makrophyten und Diasporenreservoir im Usedomer See
(Diplomarbeit, betreut durch Sven Dahlke)

Means of communication and herbicide effects in predator-prey interactions between Scorpaena porcus and Pomatoschistus spp.
(Diplomarbeit, betreut durch Claudia Kruschel und Irmgard Blindow)

Bereitstellungsketten von Landschaftspflegematerial zur energetischen Nutzung am Beispiel der Insel Hiddensee
(Bachelorarbeit (FH Stralsund), betreut durch Irmgard Blindow)