Lake water acidification and temperature have a lagged effect on the population dynamics of Isoëtes echinospora via offspring recruitment

The aquatic quillwort, Isoëtes echinospora, survived the strong water acidification during 1960s–1990s in Plešné Lake (Bohemian Forest, Central Europe), but failed to reproduce. We studied the relationships between a recent population recovery and an improvement of lake water quality. We used correlation analysis to evaluate lagged seasonal effects of lake water quality on population dynamics during the past decade, and factor analysis to determine the independent factors responsible for population recovery. We also provided a water-quality-based reconstruction of population growth from the beginning of the lake recovery two decades ago, using a partial least squares regression (PLSR) model of population growth. We identified three independent controlling factors: nutrients (nitrate, phosphorus, calcium, potassium, magnesium), stressors (pH, ionic aluminium) and temperature. Of these, nutrient availability did not limit the quillwort growth, but annual mean pH and winter mean concentrations of toxic ionic aluminium influenced population growth through negative effects on sporeling establishment until the age of one year, while cumulative temperature in spring and summer controlled the later plant growth. Thus, water quality in the acidified Plešné Lake mainly controls recruitment success rather than adult survival of Isoëtes echinospora. This study provides the first in situ evidence that the recruitment success, namely the annual increment in the adult quillwort population, indicates the degree of recovery from acidification, however further extensive investigation is required to more accurately quantify, and therefore understand, the relationships between recruitment, water quality and other factors

Student Scientific Conference MUNI Pharm 2021

The Abstract Book is issued annualy on the occasion of the Student Scientific Conference. It consists of the scientific research project abstracts in the field of pharmacy, which are submitted and presented by the students and evaluated by the scientific committee

Trial transplantation of Luronium natans to temporal refugees for the purpose of planned reconstruction of its native pond

Floating water-plantain (Luronium natans L Rafinesque) is a critically endangered aquatic macrophyte species inhabiting two localities in the north of the Czech Republic (PLA Labské pískovce). Due to planned reconstruction of one of the native localities, called Kralovomlynsky pond, it is necessary to provide survival of the endangered species. Large transplant experiment allowed for optimizing methodology for careful collection of a large amount of native plants from the pond and their transplantation to three refugees

Improving the ecological potential and water quality in reservoirs using floating vegetation islands.

The aim of the two-year experiment was to verify the ability of four species of sedges and natural pioneering plants to grow on substrate-free floating islands

Luronium natans, endangered species in Labské Pískovce PLA - results of field monitoring

The ecology of rare, strongly enadangered species Luronium natans, found in the Czech Republic only in Labské Pískovce is assumed and the results of scuba monitoring between 2002–2007 are presented

Mountain aquatic Isoëtes populations reflect millennial-scale environmental changes in the Bohemian Forest Ecosystem, Central Europe

In this study we aim to investigate millennial-scale dynamics of Isoetes, a type of macrophyte well adapted to oligotrophic and clear-water lakes. Despite its wide distribution during the Early Holocene, nowadays Isoetes is considered as vulnerable or critically endangered in many Central European countries. Using a multi-proxy palaeoecological reconstruction involving Isoetes micro- and megaspores, pollen, plant macrofossils, macro-charcoal, diatoms and chironomids from four lakes (Prasilske jezero, Plesne jezero, Cerne jezero, Rachelsee) located in the Bohemian Forest Ecosystem mountain region in Central Europe, we reconstruct Isoetes dynamics and discuss how local environmental factors impacted its distribution and abundance during the Holocene. Our results show regionally concurrent patterns of Isoetes colonisation across all lakes beginning 10,300-9300 cal yr BP, and substantially declining around 6400 cal yr BP. Results from Prasilske jezero imply that Isoetes decline and collapse in this lake reflect gradual dystrophication that led to the browning of lake water. This is evidenced by a shift in diatom assemblages towards more acidophilous taxa dominated by Asterionella ralfsii and by a decrease in total chironomid abundance and taxa sensitive to low oxygen levels. Dystrophication of Prasilske jezero was linked with the immigration of the late-successional tree taxa (Picea abies and later Fagus sylvatica and Abies alba), peatland expansion, and decreasing fire activity. Multi-site comparison of pollen records suggest that these vegetation-related environmental changes were common for the whole region. Our study demonstrates the sensitivity of Isoetes to millennial-scale natural environmental changes within the surrounding lake catchment

Characteristics, Main Impacts, and Stewardship of Natural and Artificial Freshwater Environments: Consequences for Biodiversity Conservation

In this overview (introductory article to a special issue including 14 papers), we consider all main types of natural and artificial inland freshwater habitas (fwh). For each type, we identify the main biodiversity patterns and ecological features, human impacts on the system and environmental issues, and discuss ways to use this information to improve stewardship. Examples of selected key biodiversity/ecological features (habitat type): narrow endemics, sensitive (groundwater and GDEs); crenobionts, LIHRes (springs); unidirectional flow, nutrient spiraling (streams); naturally turbid, floodplains, large-bodied species (large rivers); depth-variation in benthic communities (lakes); endemism and diversity (ancient lakes); threatened, sensitive species (oxbow lakes, SWE); diverse, reduced littoral (reservoirs); cold-adapted species (Boreal and Arctic fwh); endemism, depauperate (Antarctic fwh); flood pulse, intermittent wetlands, biggest river basins (tropical fwh); variable hydrologic regime—periods of drying, flash floods (arid-climate fwh). Selected impacts: eutrophication and other pollution, hydrologic modifications, overexploitation, habitat destruction, invasive species, salinization. Climate change is a threat multiplier, and it is important to quantify resistance, resilience, and recovery to assess the strategic role of the different types of freshwater ecosystems and their value for biodiversity conservation. Effective conservation solutions are dependent on an understanding of connectivity between different freshwater ecosystems (including related terrestrial, coastal and marine systems).Forestry, Faculty ofNon UBCForest and Conservation Sciences, Department ofReviewedFacult