Principal investigator: Jaroslav Vrba
(Co)investigator from the Department: Jaroslav Vrba
Funding provider: The Czech Science Foundation
Duration: 2017 to 2019

Project goals: 
Aim of the project is to explore plankton diversity and dynamics, key players and their functional traits, and to estimate primary production, respiration, nutrient mobilisation, and production efficiency in the hypertrophic fishponds that allow refining and testing of general ecological hypotheses.

Project description: 
Fishponds are semi-natural, man-controlled, shallow ecosystems used for fish production. Different management results in different ecological states that predestine the fishponds as unique model systems. Nutrient loads and fish overstock have led to fishpond hypertrophy; however, interactions in the plankton communities under such extreme conditions remain unexplored. We are lacking data on primary production, community respiration, diversity and functions of heterotrophic microbial food webs in eutrophic freshwaters, as well as about the effects of fish on their food web structure. We hypothesise that hypertrophic conditions result in net ecosystem heterotrophy, an increase in heterotrophic microbial biomass and nutrient mobilisation, and a decrease in net ecosystem productivity and cost effectiveness. Under the conditions of high (auto- and heterotrophic) microbial biomass, intensive photosynthesis and respiration processes cause ecosystem imbalances and low resource use efficiency that results in higher plankton (mainly microbial) diversity due to niche diversification.

(Co)investigator from the Department: Jana Jersáková
Funding provider: The Czech Science Foundation
Duration: 2018 to 2020

Project goals: 
The project aims to identify the factors underlying co-existence and niche partitioning of orchids in species-rich habitats of two climatically different regions by exploration of functional traits of orchids and their mycorrhizal fungi.

Project description: 
Plant species can co-exist under natural conditions due to niche partitioning and an association with mycorrhizal fungi is one way to differentiate resources. Orchids critically rely on mycorrhiza during life cycle, and coexistence may be strongly contingent on the functional traits (FT) of their symbionts. Congruently, co-occurring orchids tend to associate with distinct mycorrhizal communities. It is however unclear to what extent orchid mycorrhizal fungi differ in ecological strategies and corresponding FT to enable effective niche partitioning. We propose to explore FT of orchid-fungus communities in species-rich habitats of two climatically different regions with special focus on enzymatic activity and nutrient utilization of fungi, mycorrhizal specificity under different conditions and presence of endohyphal bacteria. Using bipartite network modelling and multivariate statistical models we will describe the network structure and co-variation of FT of both symbiotic partners. The FT of orchid mycorrhizal fungi will be explored in such a complex approach for the first time.

Principal investigator: David Boukal
(Co)investigator from the Department: David Boukal
Funding provider: The Czech Science Foundation
Duration: 2018 to 2020

Project description: 
Lack of data on freshwater communities in heavy-metal polluted post-industrial sites seriously hampers restoration efforts that should reflect their potential importance for biodiversity conservation. At the same time, artificially created standing water bodies in fly ash lagoons offer unique nature laboratories for studying the effects of stressors on communities.

We study conservation value and ecology of communities of these sites by combining a landscape-scale field survey with field enclosure experiments and analyses of heavy metal content across trophic levels and taxa. We aim to provide the first detailed survey of freshwater communities in these habitats, compare them with communities in nearby unpolluted sites in sandpit pools, and quantify the effects of heavy metal pollutants on individuals. This will enable us to unravel key stressors that shape these communities, provide evidence-based recommendations for their restoration, and contribute to the broad understanding of biodiversity in man-made habitats. (The project runs in collaboration with Robert Tropek from the Biology Centre of the Czech Academy of Sciences.)

(Co)investigator from the Department: Keith Edwards
Funding provider: The Czech Science Foundation
Duration: 2019 to 2021

Project goals: 
How plant functional types and phenological stages influence the quantity and quality of plant inputs under combined changes in nutrient and water levels and their impact on soil microbial community structure and processes.

Project description: 
A  mesocosm study will be conducted to determine the combined effects of nutrient and water level changes on the quality and quantity of plant inputs to the soil and how these may influence soil microbial community structure and enzymatic activities. The study will focus on the growth, allocation patterns and source-sink relationships in representative wetland species of the conservative and competitive plant functional types, and how these internal plant factors are altered at different plant phenological stages. We predict that the conservative species will grow better in far-from-optimal hydrologic conditions, but that the poorer growth of the competitive species under these conditions will be mitigated with increased nutrient supply. In addition, the competitive species will show a greater degree of plasticity under changing environmental conditions. These internal changes in plant source-sink relationships will be translated to the soil microbial community structure and activities.