438 research outputs found
Design and Implementation of a Web Application for Office Space Allocation
No full textTato bakalářská práce se věnuje návrhu a implementaci webové aplikace pro efektivní obsazování míst v kancelářích, reagující na potřeby firem v éře flexibilních pracovních režimů a rostoucích nákladů na kancelářské prostory. Práce analyzuje stávající řešení a identifikuje klíčové firemní procesy, na jejichž základě stanovuje požadavky na aplikaci. Dle sepsaných požadavků je dále součástí práce návrh, implementace a testování webové aplikace v PHP Symfony. Cílem je poskytnout řešení pro zvýšení efektivity využití kancelářských prostor, snížení nákladů a zvýšení produktivity.This bachelor thesis focuses on the design and implementation of a web application for efficient office staffing, responding to the needs of companies in an era of flexible working schedules and rising office space costs. The thesis analyses existing solutions and identifies key business processes to determine the requirements for the application. According to the written requirements, the work also includes the design, implementation and testing of a web application in PHP Symfony. The aim is to provide a solution to increase the efficiency of office space utilization, reduce costs and increase productivity
Polyphenolic profiles of invasive Sorghum halepense within the Belgrade urban and suburban area
No full textJohnson grass, Sorghum halepense (L.) Pers., is recognized as a globally successful invader and one of
the most aggressive weeds in Europe. According to data from 2012 this species had the status of a
sporadically invasive species in Serbia. Since then, S. halepense has been increasing in frequency and
range. Its populations are widespread and numerous, which represents a strong pressure on
autochthonous flora and vegetation. Considering all the aforementioned, the revision of S. halepense
status of invasiveness for Serbia is necessary, in order to improve management strategies for this
invasive species.
It is known that the allelopathic effects of plant secondary metabolites present a potential
mechanism of invasive plant success. High concentrations of phenolic compounds, with their diverse
functionality, may confer an advantage to plants in response to environmental conditions.
With the aim to examine the chemodiversity of S. halepense in Belgrade (Serbia) urban areas, we
performed UHPLC/DAD/MS2 targeted metabolomic analysis of leaves, rhizomes and inflorescences of
plants originating from 5 localities. These populations are located in the wider area of Belgrade, from
urban and suburban zones. One population from Montenegro was used as outgroup. The analysis was
targeted towards 19 polyphenolic compounds: 9 phenolic acids, 6 flavonoid aglycones and 4 flavonoid
glucosides. Phenolic acids were recognized as the dominant group of polyphenolics in samples, with
chlorogenic acid being the major compound in inflorescences and leaves, while in rhizomes p
hydroxybenzoic acid predominated. The third and fourth most abundant compounds in samples were
p coumaric acid and protocatechuic acid, respectively. Flavonoids were less abundant in the analysed
S. halepense samples. Interestingly, the amount of flavonoid aglycones (quercetin and luteolin) and
flavonoid glycosides (quercetin 3 O rutinoside, quercetin 3 O glucoside, isorhamnetin 3 O rutinoside,
and isorhamnetin 3 O rutinoside) were the highest in inflorescences. The results pointed to the
considerable differences in polyphenolics composition among plant organs. In addition, inter
population variability was also recognized. As revealed by the PCA, the population originating from
Montenegro was well distinguished from the Belgrade populations based on the metabolite profiles.
In addition, population 1 (i.e. population from Jakovo) was distinguished from the rest of Belgrade
populations.
Considering the high diversity and amount of polyphenolic compounds identified in S.
halepense, and their known phytotoxic and allelopathic effects, it might be presumed that these
compounds, at least partially contribute to fast spreading of Johnson grass in the urban and suburban
areas of Belgrade. To take advantage of this species invasiveness, we propose the usage of S. halepense
methanol extracts as bioherbicides for the effective and environmentally sustainable weed control.
Further studies should be conducted in order to test these possibilities.Pyšek P, Pergl J, Moodley D, editors. Book of abstracts: 15th International Conference on Ecology and Management of Alien Plant invasions: EMAPi 2019: Integrating research, management and policy; 2019 Sep 9-13; Prague, Czech Republic. Pruhonice: Institute of Botany, Czech Academy of Sciences; 2019. p. 102
Managing Invasive Alien Species in Forest Corridors and Stepping Stones
No full textInvasive alien species (IAS) pose a significant threat to forest ecosystems by disrupting ecological networks and competing with native species. Forest habitat patches and corridors designed to enhance connectivity and biodiversity can unintentionally promote the dispersal of IAS, further compromising the ecological integrity of the forest ecosystem. This chapter discusses two main aspects related to IAS and forest connectivity: (1) the spread of IAS in the landscape and their impacts on native species and (2) the consequences of IAS on forest connectivity. Effective management of IAS is crucial to improve connectivity for native species while restricting the spread opportunity for aliens and preserve biodiversity. Ideally, a site-specific risk analysis should precede conservation or restoration efforts, determining the potential impact of IAS on the respective habitat patch’s structural and functional connectivity, and vice versa. Furthermore, this chapter explores management strategies to control IAS, including physical removal, biological control, and monitoring. Citizen involvement and remote sensing play vital roles in supporting management actions, IAS detection and long-term monitoring, and habitat connectivity. Including stakeholders such as forest owners and managers in such actions ensures a collaborative approach to safeguarding forest ecosystems from the threats posed by IAS
Invading plants remain undetected in a lag phase while they explore suitable climates
No full textSuccessful alien species may experience a period of quiescence, known as the lag phase, before becoming invasive and widespread. The existence of lags introduces severe uncertainty in risk analyses of aliens as the present state of species is a poor predictor of future distributions, invasion success and impact. Predicting a species' ability to invade and pose negative impacts requires a quantitative understanding of the commonality and magnitude of lags, environmental factors and mechanisms likely to terminate lag. Using herbarium and climate data, we analysed over 5,700 time series (species × regions) in 3,505 naturalized plant species from nine regions in temperate and tropical climates to quantify lags and test whether there have been shifts in the species' climatic space during the transition from the lag phase to the expansion phase. Lags were identified in 35% of the assessed invasion events. We detected phylogenetic signals for lag phases in temperate climate regions and that annual self-fertilizing species were less likely to experience lags. Where lags existed, they had an average length of 40 years and a maximum of 320 years. Lengthy lags (>100 years) were more likely to occur in perennial plants and less frequent in self-pollinating species. For 98% of the species with a lag phase, the climate spaces sampled during the lag period differed from those in the expansion phase based on the assessment of centroid shifts or degree of climate space overlap. Our results highlight the importance of functional traits for the onset of the expansion phase and suggest that climate discovery may play a role in terminating the lag phase. However, other possibilities, such as sampling issues and climate niche shifts, cannot be ruled out
Contrasting patterns of naturalized plant richness in the Americas : Numbers are higher in the North but expected to rise sharply in the South
No full textWith increasing availability of plant distribution data, the information about global plant diversity is improving rapidly. Recently, Ulloa Ulloa et al. (2017) presented the first comprehensive overview of the native vascular flora of the Americas, yielding a total count of 124,993 native species. Of these, 51,241 occur in North America and 82,052 in South America. By combining these data with the information in the Global Naturalized Alien Flora (GloNAF) database of naturalized alien floras, we point out that for a complete picture of the regional and continental plant richness, the naturalized alien species need to be considered. Ignoring this novel component of regional floras can lead to an inaccurate picture of overall change in biodiversity in the Anthropocene. We show that North and South America might face contrasting challenges in terms of potential threats to biodiversity posed by alien plant species, because of the different past and present dynamics of invasions and predictions of future development. In total, there are 7,042 naturalized alien plants occurring in the Americas, with 6,122 recorded in North America and 2,677 in South America; if only introductions from other continents are considered additions to the native continental flora make up 6.9 and 1.4 %, respectively. Nevertheless, predictions of naturalized plant trajectories based on global trade dynamics and climate change suggest that considerable increases in naturalized plant numbers are expected in the next 20 years for emerging South American economies, which could reverse the present state.publishe
The role of long-distance seed dispersal in the local population dynamics of an invasive plant species
No full textData from: Autofertility and self-compatibility moderately benefit island colonization of plants
No full textAim: The current geographical distribution of species largely reflects colonization success after natural long‐distance dispersal or introduction by humans. Plants with selfing ability should have an advantage when establishing on islands where mates and pollinators are limited (Baker's law). However, high percentages of dioecious and self‐incompatible species have been reported for some islands, possibly resulting from post‐colonization evolution. Given that such evolution is less likely to apply to alien species recently introduced to islands by humans, tests of Baker's law on islands need to consider both native and naturalized alien species. Location: Global. Time period: Undefined. Major taxa studied: Angiosperms. Methods: To test whether the colonization of islands is associated with selfing ability (self‐compatibility and autofertility), we combined three comprehensive global databases: one on breeding systems of species, one on island and mainland distributions of native species and one on global naturalization of alien plants. We assigned each of a total of 1,752 species, from 161 angiosperm families, as mainland species, island colonists and/or island endemics (i.e., species that are restricted to islands). To assess potential relationships between island occurrence and selfing ability of species, we used multinomial logistic regressions.
Results: We found that species with high selfing ability were slightly more likely to be island colonist than mainland species. However, selfing ability did not increase the likelihood of being an island endemic in contrast to mainland species. Among island colonists, selfing ability did not differ between species on oceanic and on continental islands or between species native to islands and naturalized on islands. Main conclusions: We performed a comprehensive test of Baker's law by considering many angiosperm families, using continuous metrics of self‐compatibility and autofertility and including both native and naturalized species. We provide global evidence that high selfing ability may foster island colonization of angiosperms
Latitudinal patterns of alien plant invasions
No full textLatitudinal patterns of biodiversity have long been a central topic in ecology and evolutionary biology. However, while most previous studies have focused on native species, little effort has been devoted to latitudinal patterns of plant invasions (with a few exceptions based on data from sparse locations). Using the most up-to-date worldwide native and alien plant distribution data from 801 regions (including islands), we compared invasion levels (i.e. alien richness/total richness) in the Northern and Southern Hemispheres and across continental regions and islands around the globe. Results from quantile regressions using B-splines to model nonlinearity showed (1) declining richness with increasing latitude, although the highest alien richness occurs at around 40 degrees in both hemispheres, (2) decreasing invasion levels towards higher latitudes on islands but a unimodal pattern in invasion level in continental regions in each hemisphere, (3) significantly higher invasion levels on islands than in continental regions and (4) a greater variability in invasion levels on islands at low latitudes than on high-latitude islands. In continental regions, only the mid-latitudes had high variability with both low and high invasion levels. Our findings identified latitudes with invasion hotspots where management is urgently needed, and latitudes with many areas of low invasions but high conservation potential where prevention of future invasions should be the priority.publishe
atlas of plant invasion
No full textLarge-scale biodiversity data, for example, on species distribution and richness information, are being mobilized and becoming available at an increasing rate. Interactive web applications like atlases have been developed to visualize available datasets and make them accessible to a wider audience. Web mapping tools are changing rapidly, and different underlying concepts have been developed to visualize datasets at a high cartographic standard. 2. Here, we introduce the Combined Atlas Framework for the development of interactive web atlases for ecological data visualization. We combine two existing approaches: the five stages of the user-centred design approach for web mapping applications and the three U approach for interface success. 3. Subsequently, we illustrate the use of this framework by developing the Atlas of Plant Invasions based on the Global Naturalized Alien Flora (GloNAF) database. This case study illustrates how the newly developed Combined Atlas Framework with a user-centred design philosophy can generate measurable success through communication with the target user group, iterative prototyping and competitive analysis of other existing web mapping approaches. 4. The framework is useful in creating an atlas that employs user feedback to determine usability and utility features within an interactive atlas system. Finally, this framework will enable a better-informed development process of future visualization and dissemination of biodiversity data through web mapping applications and interactive atlases.publishe
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