High-throughput sequencing (HTS) of gene amplicons is a preferred method assessing microbial community composition, because it rapidly provides information from large number samples at high taxonomic resolution and low costs. However, mock studies show that HTS data poorly reflect the actual relative abundances individual phylotypes, casting doubt on reliability subsequent statistical analysis interpretation. We investigated how accurately variability bacterial eukaryotic composition their...

Photochemical transformation of dissolved organic matter (DOM) has been studied for more than two decades. Usually, laboratory or "in-situ" experiments are used to determine photodegradation variables. A common problem with these is that the done at higher ambient temperature. Five were effect temperature on photochemical degradation DOM. Experimental results showed strong dependence Mathematical modeling processes revealed different pathways engaged in DOM inorganic carbon (DIC) strongly...

Abstract This study provides insights into factors that influence the water balance of selected European lakes, mainly in Central Europe, and their implications for quality. An analysis isotopic, chemical land use data using statistical artificial intelligence models showed climate, particularly air temperature precipitation, played a key role intensifying evaporation losses from lakes. Water was also affected by catchment factors, notably groundwater table depth. The shows lakes at lower...

A multistep sample preparation method was developed to separate metal-based engineered nanoparticles (ENPs) from biological samples. The using spiked zebrafish tissues and standard titanium dioxide (TiO2) cerium (CeO2) ENPs. Single-particle inductively coupled plasma mass spectrometry used quantify the separated particles in terms of number concentration. This demonstrated recoveries more than 90% did not strikingly alter median size. High were calculated for CeO2 ENPs (>84%). Particle poor...

Acid precipitation has been shown to reduce phosphorus (P) outputs from terrestrial sources. We present field evidence that the in‐lake P cycle may also be disrupted in atmospherically acidified watershed‐lake ecosystems. Plešné Lake Bohemian Forest is an forest lake with epilimnetic pH of 4.5–4.9, total concentration ∼10 μg L −1 , and pronounced anoxia above bottom during winter summer stratification periods. The water chemistry anoxic zone develops a predictable way: After depletion...

A mass budget study of major in-lake Al fluxes, palaeolimnological data on a >10 000 year old sediment record, and in situ photochemical experiments performed at Plešné Lake (Czech Republic) suggest that liberation organically bound aluminum (Al) iron (Fe) by solar radiation is significant natural source their ionic species for lakes subsequent oxyhydroxides sediments. The results show photochemically induced transformation dissolved Fe to solid deposited dominated (91 73%, respectively)...

Forest disturbances affect ecosystem biogeochemistry, water quality, and carbon cycling. We analyzed chemistry before, during, after a dieback event at headwater catchment in the Bohemian (central Europe) together with an un-impacted reference catchment, focusing on drivers responses of dissolved organic (DOC) leaching. data regarding input to forest floor via litter throughfall, changes soil moisture composition, streamwater chemistry, discharge, temperature. observed three key points. (i)...

We systematically investigated how the combinations of size, shape and natural organic matter (NOM)-ecocorona gold (Au) engineered nanoparticles (ENPs) influence attachment particles to algae physical toxicity cells. Spherical (10, 60 100 nm), urchin-shaped (60 rod-shaped (10 × 45, 40 50 wire-shaped (75 500, 75 3000 6000 nm) citrate-coated NOM-coated Au-ENPs were used. Among spherical only 10 nm caused membrane damage algae. Only 45 induced among Au-ENPs. Wire-shaped no NOM ecocorona...

Abstract Background Planktonic microbial communities have critical impacts on the pelagic food web and water quality status in freshwater ecosystems, yet no general model of bacterial community assembly linked to higher trophic levels hydrodynamics has been assessed. In this study, we utilized a 2-year survey planktonic from bacteria zooplankton three reservoirs investigate their spatiotemporal dynamics. Results We observed site-specific occurrence microdiversification lacustrine riverine...

Pyrocatechol violet and thiocyanate methods used in the water analysis for spectrophotometric determination of aluminum (Al) iron (Fe), respectively, were modified these elements different types commonly extracts soils sediments. The digested with nitric perchloric acid an Al-heating block as total phosphorus (P) aliquots digests analyzed Al Fe. Comparison inductively coupled plasma method was demonstrated using (I) oxalate, citrate-dithionite, pyrophosphate 25 samples forest soils, (ii)...

In contrast to the well‐known nutrient transformations in circumneutral lakes, acidified water bodies may exhibit significant changes cycling due their chemistry and biology. In‐lake cycles of carbon (C), nitrogen (N), phosphorus (P) were evaluated strongly Plesné Lake (Central Europe). The lake tributaries had high concentrations dissolved organic C (DOC), inorganic N, total (TP), resulting annual averages 644, 52, 0.72 µmol L −1 , respectively. Because absence fish largely reduced...

Abstract Aerobic anoxygenic photoheterotrophic (AAP) bacteria represent a functional group of prokaryotic organisms that harvests light energy using bacteriochlorophyll‐containing photosynthetic reaction centers. They an active and rapidly growing component freshwater bacterioplankton, with the highest numbers observed usually in summer. Species diversity AAP has been studied before lakes, but its seasonal dynamics remain unknown. In this report, we analysed temporal changes composition...

Increasing levels of dissolved organic matter (DOM) in watercourses the northern hemisphere are mainly due to reduced acid rain, climate change, and changes agricultural practices. However, their impacts vary time space. To predict how DOM responds environmental pressures, we need differentiate between allochthonous autochthonous sources as well identify anthropogenic DOM. In this study distinguish allochthonous, autochthonous, a diverse watercourse network by assessing effects land cover on...

We evaluated the significance of photochemical and biological degradation allochthonous dissolved organic carbon (DOC) on in‐lake H + budgets by laboratory experiments with a mass budget study for major ions in three atmospherically acidified forest lakes Bohemian Forest. In experiments, photodegradation DOC from lake tributary resulted (1) liberation organically bound Al Fe, which consumed an equivalent amount , (2) minor decrease concentrations acid anions (A − ) despite concentrations,...

This study demonstrates the strong impact of photochemical degradation soil dissolved organic matter (DOM) on its metal complexing capacity. The role light in fate organically-bound metals transported from soils to surface waters was studied laboratory experiments. We four humic and one fulvic acid isolates different horizons Bohemian Forest (Czech Republic). Different concentrations aluminium (Al) iron (Fe) salts were added solutions acids (initial carbon (DOC) concentration 0.5 mmol L−1),...