Czech University of Life Sciences Prague
Recent publications
Heavy metal pollution in Indian wetlands is rising due to industrial, agricultural and urban development activities. Shorebirds occupy upper trophic levels and are therefore especially vulnerable to heavy metal pollution. We evaluated the concentration of heavy metals (zinc, copper, cobalt, chromium, lead and cadmium) in 22 common species of migrant shorebirds (220 shorebird dropping samples) with diverse foraging behaviors, in their different prey (55 prey samples) and in the sediments (90 sediment samples) in different habitat types (mudflats, mangroves and sand beaches) between 2019 and 2021. Further, we analyzed a total of 10 biofilm samples from mudflats and mangroves. We detected relatively low concentrations of heavy metals in the sediments (Zn concentration range: 9.11-40.91 mg/kg; Cu: 5.74-21.38 mg/kg; Co: 2.00-4.04 mg/kg; Cr: 4.05-41.03 mg/kg; Pb: 1.02-7.19 mg/kg; Cd: 0.56-4.35mg/kg). However, we measured relatively high concentrations of heavy metals in invertebrate prey species (Zn concentration range: 84.72-224.74 mg/kg; Cu: 26.63-170.36 mg/kg; Co: 13.98-14.42 mg/kg; Cr: 14.78-98.16 mg/kg; Pb: 18.95-157.29 mg/kg; Cd: 9.33-60.56 mg/kg). In addition, we found high concentrations of heavy metals in shorebird droppings (Zn concentration range: 41.33-58.8 mg/kg; Cu: 31.42-52.11 mg/kg; Co: 36.34-55.68 mg/kg; Cr: 52.3-68.21 mg/kg; Pb: 25.94-43.13 mg/kg; Cd: 5.53-16.4 mg/kg). It is evident that concentration of heavy metals increased successively moving from sediment to prey to shorebird species, likely through trophic transfer. The biofilm samples contained very high concentrations of Cr, Pb and Cd (22.64, 28.09 and 18.46 mg/kg respectively) which could be harmful to biofilm grazing shorebirds. Since bioaccumulation of heavy metals entail risks in living species, we suggest that increasing concentrations may detrimentally affect physiological processes in invertebrates and shorebirds. There is an urgent need to identify the sources of pollution and to reduce the discharge of heavy metals and other pollutants into coastal and inland wetlands.
The current selection of biomass feedstock for magnetic biochar (MBC) catalysts is highly blind. Consequently, this study delves into understanding how the types of biomass influence the iron species present in MBC catalysts. The process involved the creation of MBC through simulated impregnation-pyrolysis, utilizing six types of stalks and Fe2O3. The type of iron species significantly impacted magnetic properties and likely influenced catalytic properties of MBC. MBC's iron species type was shaped by the reduction effects of the diverse stalks on Fe2O3. During the pyrolysis, discrepancies were observed in the release of reducing gases and direct reduction for the different stalks. These differences in reduction behavior directly accounted for the distinct reduction effects. To delve deeper, the reduction behavior and effect of the main components of the stalk (hemicellulose, cellulose, and lignin) on Fe2O3 were analyzed, highlighting lignin as the most effective. Nonetheless, the absolute values of Pearson's r between lignin content in the stalk and reduction behavior/effect ranged only from 0.078 to 0.421. In contrast, the values for K, Ca, and Si content in the stalks and their influence on reduction behavior and MBC's reduction/metallization degree ranged from 0.410 to 0.910. The catalytic impacts of K and Ca were confirmed through their incorporation into cotton and reed stalks. The disparities in K, Ca, and Si content among the six stalks appeared to be the primary driver behind the diverse iron species in MBC. This work provides a scientific basis for the rational selection of biomass feedstock for MBC catalysts.
Cimex lectularius, known as the common bed bug, is a widespread hematophagous human ectoparasite and urban pest that is not known to be a vector of any human infectious disease agents. However, few studies in the era of molecular biology have profiled the microorganisms harbored by field populations of bed bugs. The objective of this study was to examine the viruses present in a large sampling of common bed bugs and related bat bugs (Cimex pipistrelle). RNA sequencing was undertaken on an international sampling of > 500 field-collected bugs, and multiple workflows were used to assemble contigs and query these against reference nucleotide databases to identify viral genomes. Shuangao bed bug virus 2, an uncharacterized rhabdovirus previously discovered in Cimex hemipterus from China, was found in several bed bug pools from the USA and Europe, as well as in C. pipistrelle, suggesting that this virus is common among bed bug populations. In addition, Shuangao bed bug virus 1 was detected in a bed bug pool from China, and sequences matching Enterobacteria phage P7 were found in all bed bug pools, indicating the ubiquitous presence of phage-derived elements in the genome of the bed bug or its enterobacterial symbiont. However, viral diversity was low in bed bugs in our study, as no other viral genomes were detected with significant coverage. These results provide evidence against frequent virus infection in bed bugs. Nonetheless, our investigation had several important limitations, and additional studies should be conducted to better understand the prevalence and composition of viruses in bed bugs. Most notably, our study largely focused on insects from urban areas in industrialized nations, thus likely missing infrequent virus infections and those that could occur in rural or tropical environments or developing nations.
Uzbekistan has a fairly high economic potential for the development of agricultural production, the formation of the necessary food resources and the development of a raw material base for the processing industry. In recent years, despite the favorable situation in the world textile market, the development of the country's cotton complex is characterized by instability and decline, market transformations in the cotton complex have led to disintegration and a significant imbalance in its functioning. The development of monopoly structures in the field of sales of the industry's products is accompanied by distortions in the pricing system. The intra-industry disunity of the enterprises of the cotton complex does not allow rational use of the existing opportunities for the dynamic development of raw cotton production, its deep processing and increasing the efficiency of the cotton complex. Currently, only a tenth of the produced cotton fiber is processed in the republic, and the rest is exported outside the country.
2 Nukus branch of Uzbek state university of physical education and sport, Street Karakalpakstanskaya, 22, Nukus, Uzbekistan 3 Uzbek-Finnish pedagogical institute, Samarqand sh., Spitamen shoh ko'chasi, 166-uy, Samarkand city, Uzbekistan. Abstract. The efficient functioning of agriculture plays an important role in ensuring food security in many countries of the world. Depending on how insurance protection of agricultural producers is carried out, the competitiveness of their financial stability and competitiveness largely depends. Agricultural insurance is one of the most effective ways to combat agricultural risks and at the same time is one of the most difficult for insurance companies. Insurance events related to natural and climatic phenomena can cause significant losses to insurance companies.
The efficiency of the functioning of agricultural enterprises largely depends on the effective use of the labor potential available to the enterprise. Labor capital defines the basis for the formation of labor potential. Labor capital depends on the acquired skills, knowledge, and skills in the process of professional retraining, training, and self-education. At the same time , the condition for the effective realization of an individual 's labor potential is his biophysical potential , his tendency to bad habits , or vice versa , commitment to a healthy lifestyle. The efficiency of the use of labor capital largely depends on the economic conditions of the habitat, the development of the health protection system, and the promotion of a healthy lifestyle among the population. The effective use of labor capital is also closely correlated with people 's motivation. In the presence of proper motivation, a person not only performs his professional duties more efficiently, but also strives for self-education, acquisition of new skills and abilities. Stable economic growth rates are possible with effective investments in human capital. Investments in human capital create prerequisites for career growth, a decent level of remuneration and a high quality of life.
The study deals with the issue of energy intensity of domestic (Czech Republic) table apple production in certified and non-certified enterprises in the Czech Republic according to the GLOBALG.A.P. standard. The aim of the study is to find out what are the differences in energy intensity (achieving output through inputs) of certified and non-certified enterprises according to the GLOBALG.A.P. standard. Also, when examining energy relationships, it was concluded that the group of certified producers expend the input energy with greater efficiency and productivity.
The purpose of the proposed article is a theoretical study of project management methods in the field of tourism and recreation, which justify the need for a modern tourist enterprise to direct efforts to the development or improvement of new products or services. The methodology is based on scientific and special research methods. Methods of analysis, synthesis, systematization, classification, generalization of economic and methodical literature, scientific publications were used. Horizontal analysis, vertical analysis, trend analysis, comparative analysis, analysis of relative indicators were also used. Scientific novely. Scientific novelty. The study of the features of various approaches to project management in the field of tourism and recreation necessitated a thorough analysis of their advantages and disadvantages. The author considered key problems in management processes and identified ways to overcome them during the implementation of tourism activities by business entities. Conclusions. The article solves important problems of the tourism sphere through the effective management of projects in tourism and recreation, the appropriate choice of price and marketing policy strategies, ensuring the quality of tourism and recreation services. based on the analysis of the considered projects in the field of tourism and recreation, we emphasize that the effectiveness of the design process depends on productive management; coordinated activity of project participants; peculiarities of national culture, resources, market conditions; strategies for the sustainable development of tourism in a specific region. Project management in the field of tourism and recreation needs to take into account the peculiarities of tourist services, which consist in the instability of demand, changes in quality and storage conditions, and correctly chosen methods of project management create opportunities for increasing the competitiveness of the destination. It has been proven that the effectiveness of project management in the field of tourism and recreation largely depends on * Corresponding author: , 070 (2023) E3S Web of Conferences IPFA 2023
The purpose of the article is to carry out the quantitative analysis of online courses in various thematic areas, which are located on Ukrainian platforms of massive open online courses (Prometheus, EdEra, OUM). On the basis of the analysis, systematization and generalization of theoretical data, the advantages and weaknesses of the MOOC use in the educational process of higher school and lifelong education are revealed. As of May 2023, they offer 558 online courses on various topics, 80 (14.3%) of which are paid. The authors found out that on Ukrainian online platforms the number of online courses have increased over the past three years compared to the previous six years. Most of the courses are located on Prometheus online platform (376 courses, 67%). All of the Ukrainian online platforms have the same courses such as “IT”, “Civic Education”, “Healthcare”, and “Psychology”. It was found that Ukrainian MOOC can provide advanced training in most disciplines of general training which is outlined in educational programmers of agrarian and food technologies specialties. In further research, we plan to research the possibility of accepting certificates proving the completion of online courses as an element of non-formal education when studying certain academic disciplines.
The article is devoted to the study of the scope and content of the activity of public authorities, the formation of a scientific basis for posing the problem of timely systemic compliance of the public authority body-the subject of public management and administration, and its activities to the conditions of transformation of the functioning environment and the formation of the concept of solving the specified problem. A systematic analysis of the scientific basis of the functioning of public power as a social system was carried out. Scientific approaches to solving the problems of improving the work of both subjects of public management and administration, as well as public authorities as a whole, have been studied. A clear understanding of the "field" of typical problems in the activity of subjects of public management and administration regarding their timely systemic adaptation in accordance with the transformation of the conditions of their functioning has been formed. The main systemic problems of the organizational and functional content of the activities of public authorities in Ukraine are singled out. The impact of this problem on the quality of public management and administration and the formation of social and political relations is analyzed.
The right choice of an oviposition site is a crucial task for oviparous species without maternal care. In contrast to well investigated biotic factors, e.g., larval food preferences, parasitism, predation, and competition avoiding, abiotic factors affecting oviposition preferences in insects have been rarely investigated in comparative studies. To improve our current understanding of oviposition site selection in Orthoptera, we investigated the influence of substrate temperature and moisture on the oviposition behaviour of 14 temperate grasshopper species. Conspecific groups of adults were kept in arenas with simultaneous temperature and moisture gradients. For each ootheca produced during the experiment (n = 1192) we recorded its depth and local microclimatic conditions. Our results indicate that microclimatic oviposition preferences significantly differ among species, however, correlations between adult habitat preferences and microclimatic oviposition preferences were surprisingly weak. Even oligothermic species preferred substrate temperatures around 30 °C and some xerothermic species preferred higher humidity. The hypothesized tendency to place oothecae closer to the ground within grass tussocks under hot and dry conditions was confirmed. It is possible that species evaluate microclimatic conditions for oviposition in the context of occupied habitat, i.e., in a relative rather than absolute manner.
The study aimed at investigating the possibility of predicting lead (Pb) in forest soils by combining terrain attributes and soil nutrients using geostatistics and machine learning algorithms (MLAs). The study was partitioned into three categories: predicting Pb in forest soil using terrain attributes and RK (Context 1); predicting Pb in forest soil using soil nutrients and RK (Context 2); and lastly predicting Pb in forest soils using a combination of soil nutrients, terrain attributes, and RK (Context 3). Stochastic Gradient Boosting-regression kriging (SGB-RK), cubist regression kriging (CUB_RK), quantile regression forest kriging(QRF_RK) and k nearest neighbour regression kriging (KNN_RK) were the modeling approaches used in the estimation of lead (Pb) concentration in forest soil. The results showed that combining the terrain attribute as an auxiliary dataset with QRF_RK proved to be the most effective method for predicting Pb in forest soil (context 1). The most effective method for predicting Pb in forest soil was to combine soil nutrients as an auxiliary dataset with SGB_RK (context 2). Combining cubist_RK with an ancillary dataset of soil nutrients and terrain attributes is the most effective method for predicting Pb in forest soils (context 3). In addition, combining ancillary variables such as soil nutrients and terrain attributes with cubist_RK generated the best results for estimating Pb concentration in forest soils. It was found that applying a robust digital soil mapping (DSM) model in combination with terrain attributes and soil nutrients is efficient in predicting the spatial distribution and estimation of uncertainty levels of lead (Pb) in forest soils based on the model’s accuracy parameters.
Small islands represent a common feature in the Mediterranean and host a significant fraction of its biodiversity. However, the distribution of plant species richness across spatial scales-from local communities (alpha) to whole islands (gamma)-is largely unknown, and so is the influence of environmental, geographical, and topographical factors. By building upon classic biogeographic theory, we used the species-area relationship and about 4500 vegetation plots in 54 Central Mediterranean small islands to identify hotspots of plant species richness and the underlying spatial determinants across scales. To do so, we fitted and averaged eight species-area models on gamma and alpha richness against island area and plot size, respectively. Based on positive deviations from the fitted curves, we identified 12 islands as cross-scale hotspots. These islands encompassed around 70% of species and habitat richness, as well as almost 50% of the rarest species in the data set, while occupying less than 40% of the total island surface. By fitting generalized linear mixed models, we found that gamma richness was mainly explained by island area and was weakly related to mean annual temperature (positively) and annual precipitation (negatively). As for alpha richness, after accounting for the idiosyncratic effect of habitats and islands, plot size and gamma richness remained the only significant predictors, showing a positive relationship. This work contributes to the understanding of the patterns and drivers of plant diversity in Central Mediterranean small islands and outlines a useful methodology for the prioritization of conservation efforts.
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6,627 members
Jaroslav Vadlejch
  • Department of Zoology and Fisheries
Jitka Horackova
  • Deparment of Landscape and Urban Planning
Asa Gholizadeh
  • Department of Soil Science and Soil Protection
Richard Mally
  • Department of Forest Protection and Entomology
Kamýcká 129, 165 00, Prague, Czechia
Head of institution
Petr Sklenička