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Subject and purpose of work: The subject of the study is urban farming and examples of urban gardens built in selected cities in North America and Europe. The aim of the study was to determine the influence of urban farming on urban landscape. Materials and methods: A case study – analysis of the ecological, spatial and social aspects of selected examples. Results: The idea of urban farming is gaining popularity and every year there are more urban gardens in cities in North America and Europe. There are several dozen urban gardens in Poland. Their structure is diversified so as to meet the needs of local communities. The character and scale of urban farming is diversified. These gardens satisfy aesthetic, scenic, ecological, social and even economic needs of small communities. They enrich the urban landscape with new, seasonally changeable enclaves of utility and aesthetic greenery. Conclusions: Urban farming is an ecological, social and spatial factor and a favourable alternative to urban landscape transformations. The development of urban farming should be successively supported by local authorities.
According to the theory of forest growth cycle, forest communities are dynamic mosaic systems composed of patches in different development stages. On basis of measurement of the four patch types [gap phase (G), building phase (B), mature phase (M) and degenerate phase (D)], the distribution pattern of different patch types and heterogeneity of the light and temperature along an altitudinal gradient were analyzed. The study forests were located in Larix chinensis forests in the Taibai Natural Reserve, and the whole forest was divided into three transects, i.e. low altitude (2900–3000 m a.s.l.), middle altitude (3100–3200 m a.s.l.) and high altitude (3300–3400 m a.s.l.). The implications of environmental heterogeneity on species coexistence and maintenance of species diversity were discussed in this paper. Our results were as follows: (1) In different elevation gradient, the proportions of the four patch types were different. Compared with low elevation and high elevation, in middle elevation, the proportions of gap phase and building phase were obviously lower; while the proportions of mature phase and degenerate phase were noticeably higher. In different elevation gradient, the distribution pattern of the four patch types was changed to some extent. (2) The daily change patterns of light and temperature in different patch types in forest cycle were different. The light intensity was much greater in gap phase than in the other three phases. The light intensity and its amplitude of changes in different patch types followed the order of G>D>B≥M. Air temperature in different patch types followed the order of G>B>D≥M. The amplitude of diurnal temperature changes in air and soil surface followed the order of G>D>B>M. (3) With elevation increasing, light intensity, the biggest air temperature, biggest soil temperature and temperature difference in four patch phase increased significantly, and average air temperature and average soil temperature significantly decreased. The spatio-temporal heterogeneity of ecological factors in different patch types in forest cycle provided a basis to maintain the coexistence of different species with different characteristics within forest community.
The paper describes impacts of the main ecological factors on the development of horse fly populations in the alluvial floodplains of the Danube River in the Pannonian plain. The study has been conducted from 2004–2009 in the four, water dependent, succession stages of alluvial forest communities of Kopacki rit wetlands. In total more than 23 000 adult horse flies of 22 species were collected by canopy traps that were placed annually during the flight season from May–September. The most abundant species during the study period were: Tabanus bromius with 47%, T. sudeticus with 17% and Haematopota pluvialis with 11%, respectively. Correlation analysis has confirmed the influence of the deviations from long-term average values in the temperature, precipitation and flood duration on the numbers of adult horse flies during the following year. A significant positive correlation has been found between spring and autumn precipitation and rainy seasons yielded more horse fly individuals the following year. A significant negative correlation has been found between the higher temperatures during summer, autumn and spring and the number of adults in the following year. The impact of the seasonal divergence from long-term average values in temperature, precipitation and flood on different species was not straightforward and different species have shown diverse correlation responses, either positive or negative.
The relation of primary production to respiration and dependence of both processes on various environmental factors were investigated in the surface waters of lakes of The Great Mazurian Lake System (GMLS) during summer seasons 2009–2011. Primary production and extracellular release was determined by ¹⁴C method, respiration (dark oxygen consumption) - by Winkler's method. Collected results allow to conclude that: (i) in all studied lakes primary production was primarily cyanobacterial, although in mesotrophic ones participation of eukaryotic phytoplankton in light CO₂ fixation was more pronounced; (ii) in mesotrophic part of GMLS primary production was limited alternately by N and P availability and less dependent on N and P regeneration processes, whereas in southern, eutrophic lakes it was primarily fueled by regeneration of biogenic substances from organic compounds and strongly limited by N resources; (iii) although in photic zone of whole GMLS respiration was dominated by heterotrophic bacteria, in its mesotrophic part also participation of other plankton components in respiration processes was significant and, (iv) that in eutrophic lakes planktonic respiration was more dependent on low molecular weight products liberated enzymatically from organic substrates than on organic compounds released by primary producers. The mean production to respiration ratio, which varied from 2.11 to 2.60 in northern, and from 2.05 to 3.67 in southern lakes suggested that during period of investigations photic zones of lakes of both parts of GMLS were net autotrophic systems.
Research into the geographical pattern of tooth size in the red fox,Vulpes vulpes (Linnaeus, 1758) in the Holarctic was conducted on a sample of 3806 skulls belonging to 41 fox populations. The Nearctic was represented by 948 specimens (249 females, 359 males, 340 specimens of unknown sex) belonging to 13 populations, whereas the Palearctic was represented by 2858 red foxes (1034 females, 1256 males, 568 specimens of unknown sex) from 32 populations. In the Nearctic, the largest foxes live on Kodiak Island (V. v. harrimani) and the Kenai Peninsula (V. v. kenaiensis), while the smallest ones live in California (V. v. necator) and Georgia (V. v. fulvus). In the Palearctic, the largest foxes come from the Far East (V. v. jakutensis, V. v. beringiana, V. v. tobolica), while the smallest are from the southern borders of the Eurasian range (V. v. pusilla, V. v. barbara, V. v. arabica). In both the Palearctic and Nearctic, tooth size in the fox varies depending on the geo-climatic factors. The fox’s tooth size confirms the general basis of Bergmann’s rule. In the Palearctic, specimens with larger teeth occur in cooler habitats with greater seasonality. These are first and foremost Northern and Far Eastern populations. In the Nearctic, tooth size in red foxes depends on the temperature and humidity of their habitat. Competition within the species and between species has important impact on the variation and dimorphism of tooth size in the red fox. Both in the Nearctic and Palearctic, red foxes from regions of sympatric co-occurrence with other closely relatedVulpes species, are more sexually dimorphic in terms of tooth size than red foxes from allopatric regions. Analysis of morphological distance on the basis of the size of dental characteristics shows, that in the Palearctic, the foxes from India (V. v. pusilla), while in the Nearctic, the population from Kodiak Island (V. v. harrimani) are most distant from the remaining populations. Geographic barriers such as the Bering Strait, Parry Channel, Mackenzie River, Kolyma and Omolon River systems have had a critical impact on red fox evolution. The most likely place for the evolution and diversification of the phyletic lineVulpes vulpes seems to be the Middle East region.
The concentration of heavy metals in the bodies of invertebrates is dependent on their physiological equipment and prevalent environmental factors. To verify the effect of some of these factors on the content of metals (Pb, Cd, Zn, Cu, Mn) we analysed and then tested (using RDA, t-test) ten species of field ground beetles (Coleoptera, Carabidae). A significant effect of Cu and Cd was discovered in terms of the sex; the males accumulated more Cu (27.520 mg kg⁻¹) than females (18.297 mg kg⁻¹) (P <0.01), which, on the contrary, accumulated more Cd (1.495 mg kg⁻¹) than males (0.663 mg kg⁻¹) (P <0.02). The content of all the metals differed significantly (P <0.03) according to the species, unambiguously showing species-specific models of accumulation. The effect of the feeding ecology was evident only on the essential elements; carnivores (Zn – 222.596 mg kg⁻¹, Cu – 27.211 mg kg⁻¹, Mn – 71.929 mg kg⁻¹) had a significantly (P <0.03) higher contents than omnivores (Zn – 168.198 mg kg⁻¹, Cu – 21.116 mg kg⁻¹, Mn – 58.452 mg kg⁻¹). Although there were differences (P <0.01) in the concentrations of Zn and Cu between the spring (Zn –163.749 mg kg⁻¹, Cu – 19.998 mg kg⁻¹) and autumn (Zn – 202.373 mg kg⁻¹, Cu – 25.496 mg kg⁻¹) species, the effect of the type of reproduction is considered to be only partial. At the same time the time of sampling affected the Zn and Mn (P <0.02) content. An important positive correlation was determined between the contents of Cu-Zn, Mn-Zn and Mn-Cu.
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