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The studies were carried out in Wielkopolska region (western Poland) in oat and winter rye cultures. Density and species structure of Thysanoptera were studied. Average density of adult Thysanoptera on oat reached 371.4 individuals/m2, and was higher than on rye, where it reached 107.5 individuals/m2. Limothrips cerealium Haliday was a dominant species on oat as well as on winter rye.
The study aimed to investigate effectiveness of forest management zoning in conserving biodiversity of Mabira forest reserve. The study sites buffer, production, and strict nature reserve management zones were purposively selected. This was undertaken through investigating woody species diversity, composition and structure. A total of 60 sampling plots with a size of 20 m x10 m were used to collect vegetation data. Variables such as woody plant species identification and counts as well as diameter at breast height (DBH) of trees were done. The result depicted a total of 65 woody species; 39 in buffer, 19 in productions and 37 in strict nature reserve. Of these, only 9 trees species were found common to all zones and their Sorensen similarity coefficient was 0.2213. The population structure of the buffer and strict nature reserve zones was found to be a J - shape pattern, whereas the production zone shown an inverted J-shape pattern. Higher woody species diversity was depicted in the buffer and strict nature zones with (H’=2. 73512) and (H’=2. 68412) respectively, and lower in a production zone (H’=1. 63628). The evenness index value of a buffer zone was (J =0. 746574), strict nature (J= 0.743335) and production (J=0. 555719). The production zone had shown higher IVI values followed by buffer and strict nature reserve zone. The most important woody species identified based on their IVI value were Broussonetia papyrifera (Production), Acalypha neptunica (Buffer), Funtumia Elastica (strict nature reserve). The existing forest management is effective in conserving the biodiversity of the forest reserve. Nevertheless, the production zone was still suffering from exploitation of the surrounding community, hence serve for protecting the remaining management zones from further human interference. Further investigation is also required on the adjacent community perceptions of the forest management zoning.
Small mammals were studied in two midfield shelterbelts (6–7 and 170 years old) in Turew area (west Poland). Eight species: Apodemus flavicollis, A. sylvaticus, A. agrarius, Mus musculus, Micromys minutus, Microtus arvalis, M. agrestis, Clethrionomys glareolus were found. Species structure was significantly different between studied shelterbelts. In the old shelterbelt species characteristic for forest environments dominated. Species structure in the old shelterbelts was more stable than in the young one.
Studies on species composition of migratory aphids with the use of Johnsons aspirator were carried out in the Agricultural Experimental Station Winna Góra in 2002–2009. The results of performed research revealed the presence of 109 aphid species. Data on their occurrence frequency showed that most numerous species were cereal aphids and accounted for 60% of all species. The most frequent cereal aphid were Rhopalosiphum padi and Sitobion avenae.
W niniejszej pracy scharakteryzowano strukturę gatunkową zieleni drzewiastej i krzewiastej na terenie Elektrowni „Szczecin”, ze wskazaniem na gatunki dobrze znoszące trudne warunki obszaru przemysłowego. W obszarze badań stwierdzono występowanie 58 gatunków i odmian drzew reprezentowanych przez 415 egzemplarzy oraz 49 gatunków i odmian krzewów, reprezentowanych przez 419 egzemplarzy. Wśród drzew i krzewów na tym terenie dominują liściaste, ze znaczącym udziałem (1/3) iglastych. Zieleń zakładowa mimo trudnych lokalnych warunków środowiskowych charakteryzuje się dobrym stanem zdrowotnym.
The purpose of the study was to suppress a known natural focus of fi eld fever exerting an infl uence on animal hosts of leptospires – small terrestrial mammals (s.t.m.) by rodenticide. After repeated application of the zinc phosphide rodenticide, the s.t.m. were regularly live-trapped and checked for leptospirosis by dark-fi eld microscopy and culture of their renal tissue and serological examination. Isolated leptospira strains were typed by help of rabbit factor sera. The deratization infl uenced the s.t.m. structure considerably: the proportion of the dominant Microtus arvalis subjects – the main reservoirs of Leptospira kirschneri serovar Grippotyphosa – were gradually and substantionally reduced and, contrarily, the percentage of the potetial hosts subjects – Clethrionomys glareolus and Apodemus fl avicollis – rose decisively over time. Changes in culture and serological positivity for leptospirosis of s.t.m. have also been enregistered. The highest original infestation of M. arvalis have slowly but strongly decreased while that of C. glareolus and A. fl avicollis has increased decisively and reached its maximum within the last years of investigation. It is probable that these two animal species have undertaken the leading role in the maintenance of the natural focus of the fi eld fever. In other animal species analogous trends were not registered. Based on these long-term fi ndings, there exists the possibility to suppress only partially and temporarily the epizootic process of leptospirosis in a natural focus that can be desirable in some circumstances (building or free time activities, etc.).
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