7 research outputs found
Impacts of climate change on vegetation distribution. No. 1: Climate change induced vegetation shifts in the palearctic region
Global average temperature has increased and precipitation pattern has altered over the past
100 years due to increases in greenhouse gases. These changes will alter numerous site factors and
biochemical processes of vegetative communities such as nutrient and water availability, permafrost
thawing, fire regime, biotic interactions and invasion. As a consequence, climate change is expected to
alter distribution ranges of many species and communities as well as boundaries of biomes. Shifting of
species and vegetation zones northwards and upwards in elevation has already been observed. Besides,
several experiments have been conducted and simulations have been run all over the world in order to
predict possible range shifts and ecological risks. In this paper, we review literature available in Web of
Science on Europe and boreal Eurasia and give an overview of observed and predicted changes in
vegetation in these regions. The main trends include advance of the tree line, reduction of the alpine
vegetation belt, drought risk, forest diebacks, a shift from coniferous forests to deciduous forests and
invasion. It is still controversial if species migration will be able to keep pace with climate change
Indication strength of coenological similarity patterns based on genus-level taxon lists and prevalence distribution
Several methods and indicators can be used to evaluate the coenological state of a given habitat, the ones which can be created simply, quickly, standardizably and reliably and which can be used to exactly quantify the state of a given habitat in point of numbers can be of outstanding practical importance in ecology. One possible method is the examination of the genera which can be found in a given habitat in great abundance and have little number of species and various ecological characteristics. For this purpose one of the most appropriate groups is that of ground-dwelling oribatid mites (Acari: Oribatida).
In our research, joining the bioindication methodological project of the “Adaptation to Climate Change” Research Group of the Hungarian Academy of Sciences, the indication strength of genus-level taxon lists and the effects of the main pattern-generating factors creating similarity patterns were analysed with the help of data series on oribatid mites collected by us and originating from literature. Our aim was to develop a method with the help of which the difference expressed with distance functions between two oribatid mite genus lists originating from any sources can correspond to spatial and temporal scales. Our results prove that these genus lists are able to express the spatial distance of the habitats. With the help of this base of comparison changes in disturbed or transformed habitats can be expressed by means of oribatid mite communities, with spatial and temporal distances
Seasonal change of oribatid mite communities (Acari, Oribatida) in three different types of microhabitats in an oak forest
Oribatid mites are one of the most abundant groups of the ground-dwelling mesofauna. They
can be found in almost every terrestrial habitat all over the world and they are characterized by great
species richness and great number of individuals. In spite of that not enough is known about their
behaviour on community level and their spatial and temporal pattern in different habitats of the world. In
our present study the seasonal behaviour of oribatid mite communities was analysed in three types of
microhabitats in a temperate deciduous forest: in leaf litter, soil and moss. Samples were collected at a
given site in a year and a half and the oribatid mite communities living there were studied on genus level
along with the changes of meteorological factors characteristic of the area. The results show that
corresponding to similar previous researches, the communities in our study do not have a seasonally
changing, returning pattern either. Based on this, we can conclude that climatic differences and
differences in other seasonally changing factors between the seasons do not have a significant role in the
annual change of communities. Besides that we discovered that the communities of the three
microhabitats are not completely the same. It is the oribatid mite community of the moss which differs
mostly from communities in the leaf litter and in the soil. Our study calls attention among others to the
fact that compositional changes of the oribatid mite communities living all over the world and their
causes are unclear to date
Climatic effects on the phenology of geophytes
Nowadays, the scientific and social significance of the research of climatic effects has become
outstanding. In order to be able to predict the ecological effects of the global climate change, it is
necessary to study monitoring databases of the past and explore connections. For the case study
mentioned in the title, historical weather data series from the Hungarian Meteorological Service and
Szaniszló Priszter’s monitoring data on the phenology of geophytes have been used. These data describe
on which days the observed geophytes budded, were blooming and withered. In our research we have
found that the classification of the observed years according to phenological events and the classification
of those according to the frequency distribution of meteorological parameters show similar patterns, and
the one variable group is suitable for explaining the pattern shown by the other one. Furthermore, our
important result is that the dates of all three observed phenophases correlate significantly with the average
of the daily temperature fluctuation in the given period. The second most often significant parameter is
the number of frosty days, this also seem to be determinant for all phenophases. Usual approaches based
on the temperature sum and the average temperature don’t seem to be really important in this respect.
According to the results of the research, it has turned out that the phenology of geophytes can be well
modelled with the linear combination of suitable meteorological parameter
Comparative analysis of the relationship between phenological phenomena and meteorological indicators based on insect and plant monitoring
Climate change is one of the biggest environmental problems of the 21st century. The most
sensitive indicators of the effects of the climatic changes are phenological processes of the biota. The
effects of climate change which were observed the earliest are the remarkable changes in the phenology
(i.e. the timing of the phenophases) of the plants and animals, which have been systematically monitored
later. In our research we searched for the answer: which meteorological factors show the strongest
statistical relationships with phenological phenomena based on some chosen plant and insect species (in
case of which large phenological databases are available). Our study was based on two large databases:
one of them is the Lepidoptera database of the Hungarian Plant Protection and Forestry Light Trap
Network, the other one is the Geophytes Phenology Database of the Botanical Garden of Eötvös Loránd
University. In the case of butterflies, statistically defined phenological dates were determined based on
the daily collection data, while in the case of plants, observation data on blooming were available. The
same meteorological indicators were applied for both groups in our study. On the basis of the data series,
analyses of correlation were carried out and a new indicator, the so-called G index was introduced,
summing up the number of correlations which were found to be significant on the different levels of
significance. In our present study we compare the significant meteorological factors and analyse the
differences based on the correlation data on plants and butterflies. Data on butterflies are much more
varied regarding the effectiveness of the meteorological factors
Old and new definitions in the spine examinations: spondylosis deformans and diffuse idiopathic skeletal hyperostosis (DISH)
SUMMARY
Background: Spondylosis deformans (SD) and diffuse idiopathic skeletal hyper ostosis (DISH) are common but mainly incidental findings in spinal radiography,
because most dogs are asymptomatic. SD is most likely an age-related vertebral
and paravertebral degeneration, DISH is a diffuse ossifying process of young,
mainly large breed dogs and cats, potentially followed by the adjacent interver tebral disc extrusion or protrusion. This phenomenon called adjacent segment
disease or degeneration (ASD).
Materials and Methods: The aim of the study was to analyse as a retrospec tive survey MRI records of 27 dogs in the Institute of Diagnostic Imaging and
Radiation Oncology of the University of Kaposvár. Subjects for the investigations
were Boxers and German Shepherds, which are the mostly predisposed breeds
to the observed diseases (SD, DISH) according to the literature. The scope of
the study was to evaluate the gender-related prevalence of the diseases in the
breeds mentioned above and to distinguish the two different pathological fea tures according to the MR images using the criteria established by the literature.
Results and Discussion: According to the statistical evaluations the authors
recognized, that the probability of spinal deformations inspected increases
exponentially by the age, however no significant difference can be recognised
in the probability of occurrence in different genders. To distinguish the SD and
DISH could be a challenging diagnostic procedure. With the use of advanced
imaging modalities such as MR, the recognition of the cases will become more
frequent. It is also recommended to use the Resnick criteria to improve the
diagnostic accuracy