Plant mycorrhizal status (a trait indicating the ability to form mycorrhizas) can be a useful plant trait for predicting changes in vegetation influenced by increased fertility. Mycorrhizal fungi enhance nutrient uptake and are expected to provide a competitive advantage for plants growing in nutrient-poor soils; while in nutrient-rich soils, mycorrhizal symbiosis may be disadvantageous. Some studies in natural systems have shown that mycorrhizal plants can be more frequent in P and N-poor soils (low nutrient availability) or Ca and Mg-high (high pH) soils, but empirical support is still not clear. Using vegetation and soil data from Scottish coastal habitats, and Latvian and Czech grasslands, we examined whether there is a link between plant mycorrhizal status and plant-available P, N, Ca and Mg. We performed the max test analysis (to examine the central tendency) and a combination of quantile regression and meta-analysis (to examine tendencies in different quantiles) on both community and plant species data combined with plant phylogenies. We consistently found no changes in mycorrhizal status at the community and species levels along the gradients of plant-available P, N, Ca and Mg in the central tendency and in almost all quantiles across all datasets. Thus, we found no support for the hypotheses that herbaceous species which are able to form mycorrhizas are more frequent in nutrient-poor and high pH environments. Obligatory, facultatively and non-mycorrhizal herbaceous species appear to assemble randomly along the gradients of nutrient availability in several European herbaceous habitats, suggesting that all these strategies perform similarly under non-extreme soil nutrient conditions.

• Klíčová slova
• Arbuscular mycorrhiza, Community mycorrhization, Eutrophication, Meta-analysis, Nutrient availability, Quantile regression,
• MeSH
• ekosystém MeSH
• mykorhiza * MeSH
• pastviny MeSH
• půda MeSH
• půdní mikrobiologie MeSH
• rostliny MeSH
• živiny MeSH
• Publikační typ
• časopisecké články MeSH
• metaanalýza MeSH
• Názvy látek
• půda MeSH

Strength and direction of plant-soil feedback (PSF), the reciprocal interactions between plants and soil, can change over time and have distinct effects on different life stages. PSF and its temporal development can also be modified by external biotic and abiotic factors such as competition and resource availability, yet most PSF research is conducted in simple experimental settings without considering temporal changes. Here I have studied the effect of different competitive settings (intraspecific, interspecific, and no competition) and nutrient addition on the magnitude and direction of biomass-based PSF (performance in conspecific relative to heterospecific inoculum) across 46 grassland species, estimated at the 4th, 10th, and 13th month of the response phase. I also examined whether conspecific inoculum had a long-term effect on plant survival at the 36th month, and whether biomass-based PSF may predict survival-based PSF effects. PSF pooled across all treatments and time points was negative, but a significant overall temporal trend or differences among competitive settings were missing. PSF developed unimodally for interspecific competition across the three time points, whereas it declined gradually in case of intraspecific and no competition. Nutrient addition attenuated negative biomass-based PSF and eliminated negative effects of conspecific inoculum on survival. Interspecific differences in biomass-based PSF were related to survival-based PSF, but only after nutrient addition. This study demonstrates that PSF is dynamic and modulated by external abiotic and biotic factors. PSF research should consider the temporal dynamics of focal communities to properly estimate how PSF contributes to community changes, preferably directly in the field.

• Klíčová slova
• Multispecies experiment, Nutrient addition, Plant competition, Plant-soil feedback, Temporal variation,
• MeSH
• biomasa MeSH
• půda * MeSH
• rostliny * MeSH
• živiny MeSH
• zpětná vazba MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• půda * MeSH

AIM: The objective of this study was to evaluate the nutrient profile of labelled foods and also understand the application of two international nutrient profiling models of labelled foods and beverages. METHODS: WXYfm and NRF 9.3 nutrient profiling models were used to evaluate 3,171 labelled foods and beverages of 38 food categories and 500 different brands. RESULTS: According to the WXYfm model, pasta, grains and legumes and frozen foods had the best scores whereas oils had the worst scores. According to the NRF 9.3 model per 100 kcal, the best scores were obtained for frozen foods, grains and legumes and milk products whereas the confectionery foods had the worst scores. According to NRF 9.3 per serving size, grains and legumes had the best scores and flavoured milks had the worst scores. A comparison of WXYfm and NRF 9.3 nutrient profiling models ranked scores showed a high positive correlation (p=0.01). CONCLUSIONS: The two nutrient models evaluated yielded similar results. Further studies are needed to test other category specific nutrient profiling models in order to understand how different models behave.

• Klíčová slova
• labelled foods, nutrient profiles, nutritional quality,
• MeSH
• analýza potravin MeSH
• informace pro uživatele zdravotní péče normy   MeSH
• lidé MeSH
• nápoje klasifikace   normy   MeSH
• nutriční hodnota * MeSH
• označování výrobků * MeSH
• potraviny klasifikace   normy   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Turecko MeSH

• Klíčová slova
• bioremediation, mineral-microbe interactions, minerals solubilization, nutrients availability, plant-microbe interactions,
• Publikační typ
• úvodníky MeSH

Few studies have evaluated the trophic level in tropical caves, and none related the microbial biomass dynamics in the immobilization of carbon and nitrogen. Here, four tropical caves of Terra Ronca State Park, Brazil, were studied: Angélica, São Bernardo, Terra Ronca I, and Terra Ronca II caves. Physical, chemical, and microbiological parameters (microbial biomass and respiration) were estimated in the dry and wet seasons. São Bernardo, Terra Ronca I, and Terra Ronca II caves presented higher nitrogen and microbial biomass nitrogen (MBN) values in the wet season than in the dry season. On the other hand, the Angélica cave showed larger amounts of nitrogen and lower MBN values in the dry season. These results indicate that caves can be adjusted in two ecological theories known as "stoichiometric decomposition" and "microbial nitrogen mining"-to the effects of nutrient availability on organic matter decomposition. The caves studied showed different environmental dynamics in relation to organic matter decomposition, which allows them to be considered unique and possess specific characteristics. Microbial biomass dynamics can be an important parameter to evaluate the availability of nutrients and ecological dynamics of the trophic network in subterranean environments.

• Klíčová slova
• Brazil, decomposition, microbial parameters, organic matter, subterranean environment,
• MeSH
• Bacteria růst a vývoj   metabolismus   MeSH
• biomasa MeSH
• dusík analýza   MeSH
• jeskyně chemie   mikrobiologie   MeSH
• půda chemie   MeSH
• půdní mikrobiologie MeSH
• uhlík analýza   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Brazílie MeSH
• Názvy látek
• dusík MeSH
• půda MeSH
• uhlík MeSH

The time of flowering is regulated by various environmental cues, and in some plant species, it is known to be affected by abiotic stresses. We investigated the effect of nutrient stress caused by an abrupt reduction of mineral nutrition on flowering of Arabidopsis thaliana. We used a hydroponic culture system that enabled us to precisely control nutrient levels. When plants were grown in full-strength nutrient solution for several weeks and then transferred to a diluted medium, the time from sowing to bud appearance was significantly shortened. This acceleration of flowering was more pronounced in short days than in long days, and stronger in the ecotype Landsberg erecta than in Columbia and San Feliu-2. The response was also affected by the age of plants at the beginning of nutrient stress and by the concentration of the diluted medium: earlier treatment and more diluted solutions strengthened the effect. Flowering was affected by nutrient stress, not by a change in the osmotic potential of the medium: addition of mannitol to a 1000-fold diluted solution had no effect on the promotion of flowering. When 3-week-old Landsberg erecta plants were exposed to 1000-fold diluted nutrient solution in an 8-h day length, flower bud appearance was strongly and reproducibly advanced by 10.8-12.8d compared with control plants (which developed buds 41.1-46.2d after sowing). This treatment can serve as an optimized protocol for future studies concerning physiological, molecular and ecological aspects of flower induction by nutrient stress in A. thaliana.

• MeSH
• Arabidopsis genetika   fyziologie   MeSH
• genotyp MeSH
• hydroponie MeSH
• květy růst a vývoj   MeSH
• minerály metabolismus   MeSH
• osmolární koncentrace MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• minerály MeSH

Rapid environmental changes across Europe include warmer and increasingly variable temperatures, changes in soil nutrient availability, and pollinator decline. These abiotic and biotic changes can affect natural plant populations and force them to optimize resource use against competitors. To date, the evolution of competitive ability in the context of changes in nutrient availability remains understudied. In this study, we investigated whether the common calcareous grassland herb Leontodon hispidus recently evolved its competitive ability and response to nutrient availability. We compared ancestors sampled in 1995 and descendants sampled in 2018 and applied a competition treatment in combination with weekly nutrient treatments (no fertilizer, nitrogen, phosphorus, and both). We found evidence for evolution of increased competitive ability, with descendants producing more vegetative biomass than ancestors when grown under competition. Furthermore, supplementing nutrients (especially N) reduced differences in competitive ability between ancestors and descendants, suggesting that nutrients are a limiting factor in interspecific competition, which could be linked to the decreasing nitrogen emissions into the atmosphere since the 1990s. Our study demonstrates rapid contemporary evolution of competitive ability, but also the complexity of the underlying processes of contemporary evolution, and sheds light on the importance of understudied potential selection agents such as nutrient availability.

• Klíčová slova
• Competition, Fertilization experiment, Global change, Rapid evolution, Resurrection approach,
• MeSH
• biologická evoluce * MeSH
• biomasa MeSH
• dusík metabolismus   MeSH
• fosfor MeSH
• pastviny * MeSH
• půda chemie   MeSH
• živiny MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• dusík MeSH
• fosfor MeSH
• půda MeSH

Poly-3-hydroxybutyrate (P3HB) is a promising alternative to persistent conventional plastics, capable of biodegrading within months. However, its microbial-driven degradation raises concerns about nutrient immobilization and impacts on plant growth. The biodegradation process occurs in multiple stages, during which shifts in the microbial community can alter soil properties and influence utilization of both intrinsic and polymer-derived organic matter. This study employs a novel approach to investigate how nutrient dynamics during the late stage of P3HB biodegradation affect lettuce (Lactuca sativa var. capitata cv. Brilliant) growth. Soil-to-sand mixtures (100_0, 80_20, 60_40, 40_60, 20_80, and 0_100 ratios) were spiked with P3HB, allowed to biodegrade for eight weeks, and then planted with sprouted lettuce seeds, which were cultivated for another eight weeks. P3HB addition inhibited plant growth and root development in all soil-sand mixtures. However, increasing the sand proportion enhanced plants' nitrogen content by 13-45 % compared to 100 % soil + P3HB. Depending on the sand-to-soil ratio, P3HB stimulated most enzymes involved in carbon, nitrogen and phosphorus acquisition. Basal and substrate-induced respirations were 9-209 % higher under P3HB addition compared to P3HB-free soil, likely due to an increase in the stabilized soil organic matter fraction. Residual P3HB analysis revealed that diluting soil with 20 % sand accelerated biodegradation, despite a decrease in bacterial abundance. In the 80_20 variant, the microbial community shifted toward higher fungal abundance, 19 % more than in 100_0 soil. While microbial proliferation was observed, it effect was outweighed by negative impacts on dry aboveground and root biomass. The highest P3HB biodegradation rate occurred in the 80_20 variant, underscoring soil texture as a critical factor in P3HB biodegradation. While microbial communities can degrade bioplastics, this process may compromise plant nutrient availability and hinder plant growth.

• Klíčová slova
• Bioplastics, Nutrient acquisition, Plant growth reduction, Soil microbes, Soil texture,
• Publikační typ
• časopisecké články MeSH

This paper presents a Guideline for calculating nutrient content of foods by calculation methods for food business operators and presents data on compliance between calculated values and analytically determined values. In the EU, calculation methods are legally valid to determine the nutrient values of foods for nutrition labelling (Regulation (EU) No 1169/2011). However, neither a specific calculation method nor rules for use of retention factors are defined. EuroFIR AISBL (European Food Information Resource) has introduced a Recipe Calculation Guideline based on the EuroFIR harmonized procedure for recipe calculation. The aim is to provide food businesses with a step-by-step tool for calculating nutrient content of foods for the purpose of nutrition declaration. The development of this Guideline and use in the Czech Republic is described and future application to other Member States is discussed. Limitations of calculation methods and the importance of high quality food composition data are discussed.

• Klíčová slova
• EU regulation, EuroFIR, EuroFIR harmonised recipe calculation procedure, Food business operators, Guideline for calculating nutrient content, Nutrition declaration,
• MeSH
• analýza potravin MeSH
• databáze faktografické MeSH
• lidé MeSH
• nutriční hodnota MeSH
• označování potravin MeSH
• potraviny * MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Česká republika MeSH

Ground- and surface-water-fed peatlands (i.e., fens) of temperate Europe face high anthropogenic nutrient loads from atmospheric deposition, agricultural catchment areas, and from peat decomposition, if drained. As a result, nitrogen loads may exceed a fen's natural nutrient removal capacity, leading to increased eutrophication of adjacent water bodies. Therefore, it is important to address possible means to decrease a fen's nutrient load, including nutrient uptake by fen plants. To assess how much fen plants can contribute to nutrient removal by uptake, nutrient stocks of above- and below-ground biomass need to be quantified. Therefore, we investigated nitrogen, phosphorous, and potassium uptake capacities of sedges (Carex species), which are common dominants in fen plant communities. We grew specimens of five Carex species with varying preferences in nutrient availability under controlled, different nutrient levels. We show that Carex above-ground biomass harvest can remove up to one third of a system's total nitrogen even at high loads of about 40 g nitrogen m-2. Species-specific differences in biomass production, rather than preferences in nutrient availability under natural conditions, were drivers of standing nutrient stocks: Highly productive species, i.e., C. acutiformis and C. rostrata, had highest nutrient standing stocks across all nutrient levels. Amounts of nutrients stored in shoots increased almost linearly with increasing nutrient levels, whereas below-ground nutrient stocks species-specifically increased, saturated, or decreased, with increasing nutrient levels. As a rough estimate, depending on the species, 6-16 cycles of annual above-ground harvest would suffice to decrease nitrogen concentrations from the highest to the lowest level used in this study. Overall, our results indicate that Carex biomass harvest can be an efficient means to counteract anthropogenic nitrogen eutrophication in fens.

• Klíčová slova
• Ecosystem restoration, Nitrogen, Nutrient removal, Paludiculture, Phosphorous, Stoichiometry,
• MeSH
• biomasa MeSH
• Carex (rostlina) * MeSH
• dusík analýza   MeSH
• ekosystém MeSH
• eutrofizace MeSH
• fosfor MeSH
• živiny MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Evropa MeSH
• Názvy látek
• dusík MeSH
• fosfor MeSH