БҚМУ Хабаршы №1-2019ж.
however, recently new genus Betaechinozercon [with the only type species
Echinozerconamericanus included, known from the Oregonian province and reported
from USA (Washington)]was established by Sikora [53] which is very similar to
Echinozercon found in the west coast of Pacific (South Korea and Japan). It was
hypothesized that Betaechino zercon originated from Echino zercon and after cross the
Beringia (and after disappearance of this land bridge) speciation occurred, visible in
additional generic features that lead to establish Betaechino zircon 53; 54; 55]. During
our studies in southern Croatia [56] we found that most of dominant species are
widespread across Holarctic, however, some others are limited to Euro-Siberian region
(Polyaspis patavinus, Zercon fageticola and Hypoaspiskargi) and only Pseudolaelaps
paulseni is considered as Mediterranean species. However, usually the mite geography
is considered as distribution within zoogeographical regions, it can be also analyzed
with regard to height above the sea level. Species that prefer mountainous areas were
e.g. Leptogamasus tatrensis and Gamasellus montanus were found in Wielkie
Torfowisko Batorowskie [57]. Similarly in Torfowiska Doliny Izery Reserve some
species were specifically found in mountainous regions: in bog Trachytes montana
(9.98%) and Gamasellus montanus (6.94%) were found, spruce stands were inhabited
bythe same species with dominances 6.28% and 5.71% respectively, in cotton grass
with dominances 9.38% and 3.13% and in dry meadow they accounted for 5.05% and
3.72% of community respectively [12].
Also the dynamics of mite populations can be example of biodiversity change.
In many studies so far the spring peak of abundance was clearly recorded with the
following (usually higher) autumn increase of abundance [58, 59, 60]. In halophyte
patches in the region of soda factory in Poland [61] mites were the most abundant in
the autumn while in the spring the lowest abundance was recorded. Interestingly, when
data from 1983 and 1986 was compared, the considerable change in the Oribatida
community structure was found which can illustrate the dynamics of mite communities
in the habitats influenced by the soda industry.In oak spinney also the autumn high
overall abundance was recorded in both Oribatida and Gamasida but in the former the
juveniles were the most abundant in October while in the latter in February. Also
changes in species composition were found, however, in Gamasida considerable
changes of dominance structure were found, which was opposite to that observed in
Oribatida. Kaczmarek et al. [60] found that in the soil of riparian meadow the juvenile
stages of Gamasida were the most abundant in spring and summer and the abundance
of oribatid and gamasid mites were positively correlated. Moreover the change in
dominance of Gamasida families was found during observation period and the single or
two species shaped the general abundance dynamics on the family level. Also the
mutual changes in two species of Hypoaspis (i.e. H. praesternalis and H.
angustiscutatus) were interpreted as intra-seasonal species-exchange which illustrate
the ecological phenomenon of lowering the interspecific competition. In the “Linie”
peatland the highest abundance of mites was recorded in winter, then it decreased to a
minimum in May and again increased in late summer [62]. Oribatid mites were
abundant in winter and late summer while in Gamasida it was found in winter and late
spring and early summer. Interestingly the Oribatida were the least abundant when the
peak of Gamasida abundance was recorded. Two families of Gamasida were the most
abundant: Ascidae and Zerconidae. In Ascidae the Platyseius italicus predominated
and the appearance of males was synchronized with appearance of juveniles of this
species, and the same was observed in the most abundant Zerconidae species: Zercon
zelawaiensis. The dynamics of mite abundance was also clear in the ecotone zone
between blackthorn thickets and wheat and barley crops [19]. In this study it was found
that gamasid mites were more abundant in crops during autumn while in spring they
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