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Suz L.M.,Royal Botanic Gardens | Suz L.M.,Imperial College London | Barsoum N.,Japan Forestry and Forest Products Research Institute | Benham S.,Japan Forestry and Forest Products Research Institute | And 18 more authors.
Molecular Ecology

Ectomycorrhizal fungi are major ecological players in temperate forests, but they are rarely used in measures of forest condition because large-scale, high-resolution, standardized and replicated belowground data are scarce. We carried out an analysis of ectomycorrhizas at 22 intensively monitored long-term oak plots, across nine European countries, covering complex natural and anthropogenic environmental gradients. We found that at large scales, mycorrhizal richness and evenness declined with decreasing soil pH and root density, and with increasing atmospheric nitrogen deposition. Shifts in mycorrhizas with different functional traits were detected; mycorrhizas with structures specialized for long-distance transport related differently to most environmental variables than those without. The dominant oak-specialist Lactarius quietus, with limited soil exploration abilities, responds positively to increasing nitrogen inputs and decreasing pH. In contrast, Tricholoma, Cortinarius and Piloderma species, with medium-distance soil exploration abilities, show a consistently negative response. We also determined nitrogen critical loads for moderate (9.5-13.5 kg N/ha/year) and drastic (17 kg N/ha/year) changes in belowground mycorrhizal root communities in temperate oak forests. Overall, we generated the first baseline data for ectomycorrhizal fungi in the oak forests sampled, identified nitrogen pollution as one of their major drivers at large scales and revealed fungi that individually and/or in combination with others can be used as belowground indicators of environmental characteristics. © 2014 John Wiley & Sons Ltd. Source

Csoka G.,NARIC Forest Research Institute | Podor Z.,University of West Hungary | Nagy G.,NARIC Forest Research Institute | Hirka A.,NARIC Forest Research Institute
Forestry Journal

We investigated the canopy recovery of 3 tree species (pedunculate oak, Turkey oak, European beech) at two locations in the Veszprém county (Western Hungary) after severe defoliation by gypsy moth caterpillars in the spring of 2005. The Turkey oak has evidently the best recovery potential, and it almost completely replaced the lost foliage in 4 months. The pedunculate oak and beech needed 2 years to reach the same level of recovery. The pedunculate oak suffered from a heavy infection of Microsphaera alphitoides after defoliation and it probably slowed down its recovery. Neither the presence of Agrilus biguttatus in the oak plot nor the appearance of Agrilus viridis in the beech plot was observed during the study period. Population density of the buprestid Coraebus floerentinus showed a considerable increase in the oak plot, but remained under the damage level. Neither other harmful appearance of other pests nor significant tree mortality were observed within 4 years from the defoliation. These results provide information for the evaluation of longer term influences of the gypsy moth defoliation and may support the decisions concerning pest control. © 2015 György Csóka et al. Source

Hlasny T.,Slovakian Forest Research Institute | Hlasny T.,Czech University of Life Sciences | Trombik J.,Czech University of Life Sciences | Holusa J.,Czech University of Life Sciences | And 10 more authors.
Journal of Pest Science

The gypsy moth is the most important defoliator of broadleaved forests in the Northern Hemisphere. We explored the patterns in the moth’s long-term dynamics and produced outbreak forecasts for seven countries located in central to southeastern Europe and extending into the Carpathian Mountains. We investigated how the outbreak periods and trends in the size of outbreak areas differ among the countries, the extent to which pest dynamics are synchronized, and how the observed patterns can be used to forecast outbreaks. We used long-term time series on outbreaks from about 1947 to 2013. The outbreak period ranged from 13 years in the northwest to 8 years in the southeast of the region; the periods were statistically significant in six of the seven countries (α = 0.05). Two distinct patterns in outbreak size were observed, i.e. while outbreak areas in the northwest were increasing, exceptionally large outbreaks occasionally occurred in the southeastern part of the region. Outbreak forecasts based on combined use of the Fourier Transform and ARFIMA approaches showed that outbreak predictability differs among the countries. An increase in outbreak areas, the control of which would require increased resources, was forecasted mainly in the central part of the region. Although the forecasts can support the forest management, there are limits to their use because of the complex relationships between the pest and the environment, which were not captured by our empirical forecasting models. © 2015 Springer-Verlag Berlin Heidelberg Source

Szocs L.,NARIC Forest Research Institute | George M.,Plant Health and Molecular Biology Laboratory | Thuroczy C.,Malomarok str. 27 | Csoka G.,NARIC Forest Research Institute
Periodicum Biologorum

Background and Purpose: Despite the importance of studying the native enemy complex of the introduced and invasive leaf miner sawfly species in their native territories, few studies have been done in recent years concerning the species component and the regulating potential of their parasitoid complexes (in both native and invaded area). Heterarthrus vagans and Fenusa dohrnii are only some of the species which are native in Palearctic area, but alien invasive in North America, causing damage on forest plantations. In this short paper we provide our original data to the knowledge of parasitoid fauna associated with seven leaf mining sawflies native in Hungary. Material and Methods: For a period of four years (2011–2014), several leaf miner species were collected and placed in single mine rearings. From the leafminers, belonging to the Tenthredinidae family, a total of 809 mines made by 9 different species (Heterarthrus wuestneii, Fenusa dohrnii, Heterarthrus vagans, Fenusa pumila, Fenusella nana, Profenusa pygmaea, Metallus pumilus, Parna apicalis, Fenusa ulmi) were collected from 19 locations across Hungary. Results and Conclusions: A total of 188 specimens of 13 parasitoid species belonging to 3 families (Braconidae – 1; Ichneumonidae – 1 and Eulophidae – 11) were reared out from our samples. Parasitoid adults were obtained from 7 of the 9 species of leaf mining sawfly hosts (Fenusa dohrnii, Fenusa pumila, Fenusa ulmi, Heterarthrus vagans, Metallus pumilus, Parna apicalis, Profenusa pygmaea). From Heterarthrus wuestneii and Fenusella nana no parasitoid adults emerged.The parasitoid species presented in this work are typically associated with leaf mining sawflies. Several new host-parasitoid associations have been described. © 2015, Croatian Society of Natural Sciences. All rights reserved. Source

Machon A.,Hungarian Meteorological Service | Machon A.,Eotvos Lorand University | Horvath L.,Hungarian Meteorological Service | Horvath L.,Szent Istvan University | And 6 more authors.
Water, Air, and Soil Pollution

This work is a synthesis of a 5-year estimation of nitrogen balance at a semi-arid, semi-natural, undisturbed grassland site (Bugac). We measured the N input of atmospheric pollutants by wet and dry deposition of gases and aerosols, while we considered N output as NO and N2O gases volatilized from soil. Besides measurements of soil fluxes, the denitrification-decomposition (DNDC) ecological model was also used and simulations were compared to and validated against the measured values. The daily flux simulations generally did not match well the measured data for N2O and NO. In most cases, the mean fluxes were underestimated, though results of the comparison of monthly values suggest that model data, together with observed deposition data, are applicable to estimate the net N balance for grasslands. The calculated yearly N balance (net flux) between atmosphere and surface, without biological fixation and effect of grazing, ranged between -9.4 and -14 kg N ha-1 year-1 as the sum of the measured deposition and emission terms, -11 to -15 and 0.9 to 2.9 kg N ha-1 year-1, respectively, between 2006 and 2010. Observed and modeled soil emissions were lower by one order of magnitude than atmospheric deposition. Considering the biological nitrogen fixation and the effect of grazing (effects of both grazed plant and excreta), the net nitrogen balance varies within -6.6 and -11 kg N ha-1 year-1. It seems - taking into account the high uncertainty in calculation due to the effect of grazing - that sources of nitrogen exceed the sinks; the surplus is probably mineralized in the soil. © 2015 Springer International Publishing Switzerland. Source

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