2012. december 31., hétfő

Bíró et al. (2013) Landscape Ecology

Biró, M., Czúcz, B., Horváth, F., Révész, A., Csatári, B., Molnár, Zs. (2013): Drivers of grassland loss in Hungary during the post-socialist transformation (1987– 1999). Landscape Ecology 5(28): 789-803., DOI 10.1007/s10980-012-9818-0


Abstract
The increase in the speed of land-cover change experienced worldwide is becoming a growing concern. Major socio-economic transitions, such as the breakdown of socialism in Europe, may lead to particularly high rates of landscape transformations. In this paper we examined the loss of semi-natural grasslands in Hungary between 1987 and 1999. We studied the relationship between 9 potential driving forces and the fate of grasslands using logistic GLMs. Grassland loss was found to be very high (1.31 % per year), which is far higher than either before or after this period. The most influential predictors of grassland loss were environmental and landscape characteristics (soil type, area of remnant grassland patches), and the socio-economic context (distance to paved road, and nearest settlement, human population density). Several processes and relationships can only be understood from a historical perspective (e.g. large extent of afforestation, strong decrease of soil water table). Grassland loss during the study period emerged as a consequence of survival strategies of individual farmers seeking adaptation to the changing environmental and socio-economic conditions, and not urbanization and agricultural intensification which are the main underlying drivers for the ongoing landscape transformations in most parts of the developed world. Though globalization increasingly influences local land use decisions, reconstructing and modelling recent landscape changes cannot be done without a proper understanding of local history and culture. Our analysis shows the importance of large-area yet high resolution landscape change research, which may reveal unexpected patterns of land cover change, undetected at coarser scales.

Keywords
East-Central Europe, Land-cover change, Logistic GLMs, Proximate and underlying driving forces

Kovács et al. (2012) Journal of Environmental Management

József Kovács, Mária Nagy, Brigitta Czauner, Ilona Székely Kovács, Andrea K. Borsodi, István Gábor Hatvani (2012): Delimiting sub-areas in water bodies using multivariate data analysis on the example of Lake Balaton (W Hungary). Journal of Environmental Management 110(15): 151–158.http://dx.doi.org/10.1016/j.jenvman.2012.06.002



Abstract
The main aim of the European Water Framework Directive (WFD, 2000) is to commit European Union Member states to the achievement of good qualitative and quantitative status for all water bodies by 2015. To achieve this, a reference state has to be determined and appropriate monitoring has to be carried out. Based on the fact that the WFD classifies Lake Balaton, the largest shallow freshwater lake in Central Europe, as one water body, and due to the lack of funds, the number of sampling locations on the lake was decreased. The aim of this study was to determine how many sub-areas with different WFD-related attributes (in this case, parameters) can be delimited in the so-called one water body of Lake Balaton, so that a number of representative sampling locations might be retained. To determine Lake Balaton's different water quality areas (i.e. sub-areas of water body) 23 parameters (inorganic compounds) were examined from 10 sampling locations for the time interval 1985–2004 using cluster- and discriminant analysis, and Wilks' lambda distribution. With cluster analysis we were able to determine two time intervals (1985–1997 and 1998–2004) with three patterns of sub-areas, two from the first and one from the latter interval. These patterns pointed to the fact that for the whole investigated time interval (1985–2004) a total of five sub-areas were present, changing in number and alignment. Then the results were verified using discriminant analysis, and the parameters which influenced the sub-areas the most were determined using Wilks' lambda distribution. The conclusion was that to be able to follow the changes in alignment of the sub-areas and to get a comprehensive picture of Lake Balaton, a minimum of five sampling locations should be retained, one in each sub-area. Based on this study the Water Authorities chose to keep five out of ten sampling locations so that the sub-areas could be described. We consider this a great success and the methodology as an example for setting up sub-areas in a water body.


Highlights
► Sub areas of a water body are determined for monitoring purposes. ► Five sub-areas are present in Lake Balaton (1985–2004). ► Multiple cluster analyses applied with coding. ► Inorganic parameters influence the formation of the sub-areas the most. ► Based on this study, five out of ten sampling locations were retained.


Keywords
Cluster analysis, Discriminant analysis, EU Water Framework Directive, Lake Balaton, Monitoring, Water body sub-areas, Wilks' lambda distribution

Lendvay & Kalapos (2012) Plant Species Biology

Lendvay, B. and Kalapos, T. (2012), Population dynamics of the climate-sensitive endangered perennial Ferula sadleriana Ledeb. (Apiaceae). Plant Species Biology. doi: 10.1111/1442-1984.12003


Abstract
Ancient plant species surviving in isolated small populations are particularly vulnerable to extinction, therefore understanding their population dynamics is necessary for conservation. The iteroparous perennial relic endemic Ferula sadleriana Ledeb. (Apiaceae) is restricted to seven distant localities in the Carpathian Basin, where it inhabits rocky hills. We monitored the species' largest population on the Pilis Hill, Hungary, over 14–19 years (depending on trait) between 1979 and 2010, and relationships were sought between climatic properties and population attributes. The population of 4000 ± 1509 emergent individuals underwent large interannual fluctuations, with the vegetative stage displaying sevenfold and the reproductive stage twenty-eight-fold differences. Spring and early summer precipitation had a marked influence on abundances and seed set. Alternating years of high and low counts of reproductive plants suggest costs of reproduction that most probably incur prolonged dormancy and retrogression to the vegetative stage. Seed set was positively influenced by number of reproductive plants over years and by plant size within a year. Ungulates nullify yearly reproductive output by grazing on reproductive individuals. This is particularly intense in dry summers, when reproductive output is already low. The strong precipitation response of abundance, absence of clonal propagation and soil seed bank, and geographical isolation of the populations place F. sadleriana at considerable risk under an increasingly variable and extreme climate. Management should seek to maintain the species' original habitat mosaic (potentially compensating for climate variation), minimize grazing damage and anthropogenic disturbance, and establish ex situ conservation programs to provide propagules for eventual reintroduction.


Keywords
grazing damage, polycarpic perennial, population monitoring, prolonged dormancy, relic endemism

2012. december 18., kedd

Popiela et al. (2012) Acta Societatis Botanicorum Poloniae

Popiela A., Lysko A., Wieczorek A., Molnár V., A. (2012): The distribution of Elatine hydropiper L. (Elatinaceae). Acta Societatis Botanicorum Poloniae 81: 137–143.



Abstract
A distribution map of Elatine hydropiper L. (Elatinaceae), which belongs to the Euro-Siberian phytogeographic element, has been prepared based on literature and web-based data. The distribution range of the taxon, comparison to previous maps and reliability of the results are discussed.



Keywords
vascular plants, Elatinella, map, chorology, Isoëto-Nanojuncetea, Europe, Asia

2012. december 10., hétfő

Purger et al. (2012) Journal of Biological Research

Purger, J. J., Kletečki, E., Trócsányi, B., Mužinić, J., Purger, D., Széles, G. L., Lanszki, J. (2012): The Common Leadwort Plumbago europaea L. as a natural trap for the wintering Goldcrests Regulus regulus: a case study from Adriatic islands. Journal of Biological Research 17: 176-179.


Abstract
Goldcrests Regulus regulus are found wintering in high numbers from October to April in the Adriatic coast and islands, feeding mainly on insects in the undergrowth and on the ground. Common Leadwort Plumbago europaea L. continues to flower on stone walls well into October, exposing its sticky calyx and seed capsules for at least 30 days, meaning a threat to small birds by clinging to their feathers. The entangled feathers restrain the birds in their free movement, which either die or become easy prey for cats, rats or birds of prey. As estimated from plant coverage rate (0.63% of stone walls) and the number of observed birds “captured” by Common Leadwort (5), at least 47 Goldcrests could have been killed by this natural trap in the built-in area of the island of Olib (0.388 km2) during one month. At lower coverage rates (<0.1%) such as in the outer areas of the island of Olib and in the outskirts and central areas of neighboring Silba island, such losses could be much lower, but because of the considerable distribution overlap between of this plant species and the wintering areas of Goldcrests, this mortality factor should not be overlooked.


Keywords
natural trap, mortality, threatening factor, Mediterranean island

Purger et al. (2012) Polish Journal of Ecology



Abstract
The number of ground-nesting bird species in meadows, one of the most vulnerable habitats in the ornithological reserve of Vrana Lake Nature Park has decreased in recent decades. Nest survival rates were investigated in meadows and reed beds using nest predation experiments in late March and in May 2005. Predators damaged 18% of the 50 artificial nests placed in the pasture meadow habitat in March and 22% in May. Daily survival rate of nests were found to be similar in March (97%) and May (96%). In May, 64% of 25 nests located in the reed bed were discovered by the predators, with the daily survival rate of nests (90%) being significantly lower than that of nests in the nearby meadow. The results suggest that the reasons for the decreasing number of nesting bird species may be – instead of the pronounced presence and activity of predators in the area – the shrinkage of meadow area, the lack of buffer zone, the proximity of agricultural lands, and disturbance caused by intensive grazing.


Keywords
artificial nest, predation, survival rate, threats, Vransko jezero

Purger et al. (2012) Bird Study



Abstract
The use of plasticine eggs coated with a thin layer of rubber instead of entirely plasticine eggs in dummy nests reduced the unnaturally high nest predation rate caused by attracted small mammals, while also enabling the identification of nest predators.

Fehér et al. (2012) North-Western Journal of Zoology

Z. Fehér, C. Albrecht, Á. Major†, S. Sereda & V. Krízsik (2012): Extremely low genetic diversity in the endangered striped nerite, Theodoxus transversalis (Mollusca, Gastropoda, Neritidae) – a result of ancestral or recent effects? North-Western Journal of Zoology 8(2): 300-307.


Abstract
The striped nerite (Theodoxus transversalis), once a widespread freshwater snail, is of high conservation priority as the majority of its populations have become extinct during the past few decades. We have performed a preliminary study to calculate intraspecific variability of the T. transversalis using two different DNA markers, the mitochondrial cytochrome c oxidase subunit I (COI) and the intron of the nuclear-coded ATP synthase subunit α (ATPSα). Surprisingly, the intraspecific variability is very low; we have found only three closely related haplotypes of each marker. Considering that the sampling sites represent well the whole present range of the species, this phenomenon seems to be the consequence of a historical bottleneck. In our view, the whole Holocene range has been colonized by descendants of a bottlenecked population. Low genetic diversity, however, was not an obstacle for this species to obtain a relatively wide range and abundance until the recent past. Comparison with other Theodoxus species of similar sized historical ranges raises the idea that possibly reduced genetic diversity accounts for the species' high sensitivity to water quality and habitat alteration. Based on these data, the species represents a single management unit for conservation, i.e. each viable population shall play an equal role in the preservation of the species in the future. To prevent the extinction of Theodoxus transversalis, high priority should be directed to the maintenance of suitable habitat conditions as well as monitoring the conservation status of persistent populations.


Keywords
bottleneck, demographic history, intraspecific molecular diversity, mismatch distribution, mitochondrial COI, nuclear-coded ATPSα, Theodoxus transversalis

Markó et al. (2012) North-Western Journal of Zoology

B. Markó, Zs. Czekes, K. Erős, E. Csata & A.M. Szász-Len (2012): The largest polydomous system of Formica ants (Hymenoptera: Formicidae) in Europe discovered thus far in Romania. North-Western Journal of Zoology 8 (2): 287-291.

Abstract
Polydomy is a rather general trait in ants. In Europe, mainly territorial mound building Formica species apply this strategy in the native fauna. Here we present the largest European polydomous system for Formica exsecta Nyl. which consists of 3,347 nests dispersed over ca. 22 ha in Transylvania, Romania. The whole population includes six additional smaller polydomous systems and comprises a total of 3,899 nests. Nest density shows considerable variations within the largest system. Ant nests are larger at the high nest density site. In addition, ant nest connectivity through shared aphid colony use with other nests can also reach extreme low (0 connections) and high (10 connections) values. These variations could reflect differences in the level of integration of single nests into a polydomous system.


Keywords
ants, aphids, connectivity, foraging, Formica exsecta, polydomy

Kurucz et al. (2012) North-Western Journal of Zoology

K. Kurucz, L. Bertalan & J.J. Purger (2012): Survival of blackbird (Turdus merula) clutches in an urban environment: experiment with real and artificial nests. North-Western Journal of Zoology 8 (2): 362-36.


Abstract
During 2009 and 2010 in the city of Pécs (Hungary) 59 active blackbird (Turdus merula) as well as 59 artificial nests were observed. Among the real nests 26 (44%) were successful, 14 (24%) were predated, and 19 (32%) were abandoned by the parent birds. Among the artificial nests 34 (57%) remained intact, but 25 (42%) were predated. Regarding the failure of real nests, if we consider both predation and abandonment during the incubation period, the daily survival rates of real nests (n = 59) DSR (0.952) were significantly lower than the DSR of artificial nests (0.977). If we consider only predation rates (n = 41), the daily survival rates of the two nest types did not differ significantly (real nests 0.976, artificial nest 0.978). Consequently, the daily survival rates of artificial bush nests used by us reflect precisely the predation pressure on real blackbird nests.


Keywords
predation, artificial bush nests, quail eggs, plasticine eggs, Hungary