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Fires will become an increasingly frequent perturbation even under the conditions of the mild climate zone and will interfere with the agricultural landscape. Fire is a natural phenomenon, and depending on ecosystems, vegetation may develop and contribute to the occurrence and spread of fire. Vegetation of the sour cherry orchard located in the climatically dry conditions of the South Moravian Region, Czech Republic (CR), was evaluated. Vegetation assessment was performed using phytocenological relevé. In each variant, 10 relevé were recorded. Coverage of the found species was estimated directly in percentages. Moreover, the maximum height in the stand was measured for each type of plant. Biomass of individual plant species was calculated, using the biomass index (IB) equation. The IB values of individual plant species in the treatments were processed by employing a multidimensional analysis of the ecological data. Different vegetation management practices in an orchard change the species diversity of the vegetation and thus the fire hazards in the orchard conditions. Grassy interrow has the most grass biomass during the entire vegetation season, and therefore represents the greatest hazard and spread of fire. The most important grasses include Arrhenatherum elatius, Dactylis glomerata, Festuca pratensis, Lolium perenne, and Poa pratensis. On the contrary, bare soil conditions in the interrow are most suitable for annual species, and this is the place with the highest changes in the number of species during the growing season. Biomass of the orchard vegetation combined with dry and warm weather increases the fire hazard. Annual and perennial grasses have very good potential for the production of biomass, which increases the hazard of fire. The nature of the vegetation in the orchards has the potential for the actual start of a fire and its subsequent spread, however, under other environmental conditions. During hot and dry weather, dead biomass may accumulate resulting in increasing the hazard of large wildfires. Varied orchard management practices lead to a higher diversity of vegetation and make orchards, islands of biodiversity in the agricultural landscape. [ABSTRACT FROM AUTHOR]

Biochar is known to be a promising material for the treatment of contaminants in wastewater and soil. In this research, wastewater samples collected at the tertiary stage from a WWTP located in the North Bohemia region of Czechia and containing 20 pharmaceutical contaminants were treated with the same biochar (wood and maize cob feedstocks, pyrolysis temperature of 470 °C), but of different doses (0.1 g L−1, 0.25 g L−1, 0.5 g L−1). In this case study, we aimed to verify the impacts of biochar application and/or concentration on the sorption of pharmaceuticals in water. The treated water was later used for irrigating planted (ryegrass taken as the plant model) and unplanted agricultural soils in a pot experiment. Soils and ryegrass samples were examined again for potential pharmaceutical existence, and the soil microbial activities were determined through fluorescein diacetate hydrolytic activities (FDHA). Results showed that most pharmaceuticals concentrations were significantly, but not totally, reduced from the wastewater upon biochar addition. Contaminants such as 3-hydroxycarbamazepine and metoprolol were entirely removed from the wastewater after 0.25 g L−1, whilst bezafibrate did not decline even at 0.5 g L−1. Moreover, the concentrations of pharmaceuticals in ryegrass biomass and soils were dominantly below detection limits or at very low doses. Finally, there were no significant differences in the microbial activities of the soils. This implicates that biochar could be approached as a good substrate for eliminating pharmaceuticals from wastewaters used for agricultural irrigation; however, more similar studies need to be carried out. [ABSTRACT FROM AUTHOR]

In order to understand the effect of phytotoxic tropospheric ozone (O3) on terrestrial vegetation, we quantified the impact of current O3 concentration ([O3]) on net ecosystem production (NEP) when compared to the conditions of the pre-industrial era. We compared and tested linear mixed-effects models based on [O3] and stomatal O3 flux (Fsto). The managed ryegrass–clover (Lolium perenne and Trifolium pratense) mixture was grown on arable land in the Czech Republic, Central Europe. Values of [O3] and Fsto were measured and calculated based on resistance analogy, respectively, while NEP was calculated from eddy covariance CO2 fluxes. We found the Fsto-based model more precise when compared to measured NEP. High Fsto was found even at low [O3], while broad summer maximum of [O3] was not necessarily followed by significant NEP decline, due to low soil water content leading to a low stomatal conductivity and Fsto. Comparing to low pre-industrial O3 conditions, current levels of O3 resulted in the reduction of cumulative NEP over the entire growing season, up to 29.7 and 13.5% when the [O3]-based and Fsto-based model was applied, respectively. During the growing season, an O3-induced reduction of NEP ranged between 13.1% in May and 26.2% in July when compared to pre-industrial Fsto levels. Looking to the future, high [O3] and Fsto may lead to the reduction of current NEP by approximately 13.3% on average during the growing season, but may increase by up to 61–86.6% in autumn, indicating further O3-induced acceleration of the senescence. These findings indicate the importance of Fsto and its inclusion into the models estimating O3 effects on terrestrial vegetation. The interaction between environmental factors and stomatal conductance is therefore discussed in detail. [ABSTRACT FROM AUTHOR]