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121.
Dragana Jurić Dinko Puntarić Vlatka Gvozdić Zdenko Lončarić Ada Puntarić 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2017,67(3):270-277
Biomonitoring of the local population and environmental monitoring in eastern Croatia have revealed abnormalities in metal and metalloid distribution that could be related to war activities during the 1990s. The goal of this study was to determine whether there are differences in the concentrations of metals and metalloids by comparing locations of high and low-intensity combat activity; we also evaluated a possible connection between metal contamination in soil and in humans. We sampled 14 locations and measured the concentrations of 20 war related metals and metalloids (Al, As, B, Ba, Cd, Co, Cr, Cu, Fe, Hg, Li, Mg, Ni, Pb, Sb, Si, Sr, U, V and Zn). The results of principal components analysis showed two main clusters: locations Dopsin and Dalj (both characterized by high-intensity combat activity), where the concentrations of most elements (except Hg) were increased. Although the concentrations of metals and metalloids in cabbage samples collected in eastern Croatia did not exceed the maximum allowed values, the results of our study confirmed existance of environmental ‘hotspot’ with higher concentrations of war metals and metalloids. Our findings indicate that there is a possible common source and mechanism of transferring metals from the environment to the population. 相似文献
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Jiří Kamler Miloslav Homolka Miroslava Barančeková Jarmila Krojerová-Prokešová 《European Journal of Forest Research》2010,129(2):155-162
Browsing of overabundant free-living herbivores often limits the natural as well as artificial regeneration of forest in Central-European
Mountains. The aim of the study was to assess the efficiency of the extensive reductions of herbivore populations for protection
of forest regeneration in preferred areas. We analysed the relationship between the intensity of shoot browsing and relative
density of herbivores in viewpoint of natural regeneration of secondary mountain spruce stands with low proportion of broadleaved
trees in Králicky Sněžník Reserve (Czech Republic). The distribution of seasonally migrating herbivores was established by
counting faecal pellet groups (standing crop method) in growing season. The intensity of browsing of spruce, beech and rowan
was assessed using the proportion of browsed shoots on individual tree sapling. Density of red deer was re-counted from the
number of pellet groups and it was 15–56 individual/km2. The intensity of spruce browsing was low in the whole area in all seasons. In general, the intensity of rowan and beech
shoot browsing was high in the whole area. There were no correlations between deer density and browsing intensity of rowan
(browsing was severe in all plots). We conclude that the natural regeneration of attractive trees and shrubs is nearly impossible
in habitats where proportion of these food items is too small, even when the density of herbivores is low. Reduction of herbivores
density is useful for protecting spruce and other tree species with low preference by herbivores. Forest managers should take
into account the high palatability of deciduous tree species and distribution of herbivores on localities. Preference of localities
is often based on grasses in the food supply. Regeneration of highly palatable tree species requires both low density of herbivores
and sufficient protection of saplings. 相似文献
124.
Ur?a Vilhar Michael Starr Klaus Katzensteiner Primo? Simon?i? Lu?ka Kajfe?-Bogataj Jurij Diaci 《European Journal of Forest Research》2010,129(4):729-740
Two models for calculating the forest water balance were applied to different development stages of managed and non-managed
forests in the Dinaric Karst for two hydrologically contrasting growing seasons. A simple model WATBAL, which calculates water
balance on a monthly basis, and the BROOK90 model, which calculates water balance on daily basis, were used. Differences between
calculated drainage fluxes between the models were less pronounced in the drier growing season and were lower in the forest
stands compared to forest gaps. Average calculated drainage fluxes of the two growing seasons were highest in the gaps and
lowest in the stand in the virgin forest remnant, followed by the mature stand in the managed forest. According to model fitting,
testing the calibration robustness and sensitivity analysis the BROOK90 model was considered best at simulating the water
balance of the various research sites. The difference in model behaviour is considered to be mainly the result of the difference
in model time step and the inclusion of macropore flow in BROOK90. The greater complexity of the BROOK90 model meant it could
be parameterized to describe more fully the complexity of the horizontal and vertical structure of forest stand and soil properties.
A disadvantage of the BROOK90 model is the greater need of input data. WATBAL, however, was useful for obtaining rougher estimates
of the water balance components and can be applied to areas where there is less data available. Choice of model is therefore
determined by data availability. 相似文献
125.
Species of Armillaria were identified from 645 isolates obtained in a nation‐wide survey in Albania. The material was collected from ca. 250 permanent plots, established for monitoring forest health, and from forests and orchards attacked by Armillaria. Armillaria mellea s.s. occurred on several coniferous and broadleaved trees in most areas examined, although it was absent above 1100–1200 m in northern Albania. This species damaged Abies and Quercus spp. and, to a lesser extent, other forest trees. Armillaria mellea was also commonly recorded causing damage in orchards and vineyards. Armillaria gallica was a common saprophyte or weak pathogen in coniferous and deciduous forests at altitudes from 600 to 1600 m, and less commonly on oaks at lower altitudes. Armillaria ostoyae was rare in central and southern Albania, but common in northern Albania, causing significant damage to pine and other conifers, mostly at altitudes from 600 to 1800 m. Armillaria cepistipes was recorded at altitudes from 800 to 1800 m as a saprophyte or weak pathogen on conifers and deciduous trees, mostly in beech and silver fir forests. Armillaria tabescens was found in oak forests at altitudes from sea level to 900 m. In orchards, A. tabescens occasionally attacked almond and pear trees. Armillaria borealis was found in a few locations in northern Albania, at altitudes from 800 to 1800 m. 相似文献
126.
Molecular tracing of the transmission routes of bois noir in Mediterranean vineyards of Montenegro and experimental evidence for the epidemiological role of Vitex agnus‐castus (Lamiaceae) and associated Hyalesthes obsoletus (Cixiidae)
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Epidemiological aspects and transmission routes of bois noir (BN), a grapevine yellows disease induced by ‘Candidatus Phytoplasma solani’, have been exhaustively studied in the affected vineyards of continental Europe but not in the Mediterranean coastal zone. Because ‘Ca. Phytoplasma solani’ and its principal vector Hyalesthes obsoletus presumably originate from the Mediterranean, gaining knowledge of the epidemiological peculiarities of the disease in this area is essential for understanding its global spread and diversification, as well as for designing local management strategies. In this study, molecular epidemiology was applied to trace transmission pathways of ‘Ca. Phytoplasma solani’ in the Mediterranean vineyards of Montenegro, using multilocus sequence typing of tuf, vmp1 and stamp genes of the isolates associated with various hosts. Thus, ‘Ca. Phytoplasma solani’ was tracked from a tentative reservoir plant (inoculum source) through an associated vector population to the infected grapevine. Three pathways of transmission were documented, originating from Urtica dioica, Convolvulus arvensis and Vitex agnus‐castus; however, only the route originating from U. dioica was direct, whereas the latter two were overlapping and could be intermixed. Vitex agnus‐castus is a natural source of ‘Ca. Phytoplasma solani’, representing an important link in disease epidemiology in the Mediterranean and a possible origin of several genotypes occurring in central Europe. Experimental confirmation of the role of Vitex‐associated H. obsoletus in BN transmission in Montenegrin vineyards indicates its tentative role as a vector in the wide area of the Mediterranean, where some of the major wine‐producing regions are located. 相似文献
127.
128.
129.
Thibaut Olivier Vaidevutis Šveikauskas Elisabeth Demonty Kris De Jonghe Pascal Gentit Mojca Viršček-Marn Sabine Grausgruber-Gröger Sébastien Morio Francesco Faggioli Michèle Visage Frédéric Fauche Maria Gusina Marta Luigi Helena Lasner Irena Mavrič-Pleško 《European journal of plant pathology / European Foundation for Plant Pathology》2016,144(3):645-654
130.
Integrative approach of histopathology and histomorphometry of common carp (Cyprinus carpio L.) organs as a marker of general fish health state in pond culture
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Božidar Rašković Stanislav Čičovački Miloš Ćirić Zoran Marković Vesna Poleksić 《Aquaculture Research》2016,47(11):3455-3463
The semi‐intensive system of common carp monoculture in earthen ponds is currently the most practiced fish rearing system in several countries in Eastern Europe. This system is based on the addition of supplemented feed to ponds to achieve faster growth. In this study, the general state of the fish health was monitored when three different types of feeds were used: grain cereals (CF), commercial pelleted feed and extruded feed. The markers used were: (i) the histopathological index (HP) of the main organs: gills, liver and kidney; and (ii) the histomorphometric parameters of the hepatocytes and enterocytes to assess the state of the digestive system in fish fed different types of supplemented feed. At the end of the experiment, the fish were in good health, since irreversible lesions were not noticed to a greater extent in any of the fish organs. There were also no other severe lesions present. However, the results showed differences in the HP indices of the liver and gills, as well as the total HP index, indicating a better health status of the fish in the CF group. The histomorphometric results showed larger cytoplasmic areas of hepatocytes in fish fed CF, which is attributed to glycogen accumulation and higher numbers of goblet cells in the distal intestines of fish fed compound feeds. This can be attributed to slight inflammation. 相似文献