INVASIVE PLANT SPECIES AND GROUND BEETLES AND ANTS AS POTENTIAL OF THE BIOLOGICAL CONTROL: A CASE OF THE BOJČIN FOREST NATURE MONUMENT (VOJVODINA PROVINCE, SERBIA)

Osnovni cilj i zadatak provedenog istraživanja bio je utvrđivanje prisutnosti invazivnih biljnih vrsta na području zaštićenog prirodnog dobra Spomenik prirode "Bojčinska šuma" (Vojvodina, Srbija). Istraživanja flore i vegetacije Bojčinske šume rađena su tijekom više vegetacijskih sezona od ožujka 2009. do studenog 2011. godine. Bogatstvo flore ogleda se kroz prisutnost 185 biljnih vrsta koje su zabilježene na području Bojčinske šume. Od ukupnog broja zabilježenih biljnih vrsta, 31 takson je označen kao invazivna vrsta, što čini 16,76 % ukupne flore Bojčinske šume. Među njima, prisutno je 9 drvenastih biljnih vrsta i 22 zeljaste biljne vrste. Od drvenastih biljnih vrsta posebno treba istaći čivitnjaču, koja formira gust pojas uz kanal Jarčina zajedno s trskom. Treba istaći da vrsta Symphyotrichum lanceolatum formira pojas širine 4 m uz rub šume (granica s livadom), u kojemu je potisnula gotovo sve druge biljne vrste. Od ukupnog broja zabilježenih invazivnih vrsta biljaka, najveći broj pripada porodici Asteraceae (8 vrsta), zatim porodicama Rosaceae i Fabaceae (sa 3 vrste), slijede porodice Oxalidaceae i Amaranthaceae (sa 2 vrste), dok su ostale porodice zastupljene s jednom vrstom.Tijekom 2011. godine istraživana je fauna kukaca Bojčinske šume, s posebnim osvrtom na gospodarski značajne vrste. Utvrđeno je da Bojčinsku šumu naseljavaju ukupno 93 vrste kukaca. Vrlo značajno mjesto među njima zauzimaju trčci (Carabidae), u okviru kojih postoje predatori mnogih štetnih vrsta kukaca. U Bojčinskoj šumi pronađeno je ukupno 9 vrsta i 3 podvrste trčaka. Tri vrste mrava su za sada registrirane na ispitivanom lokalitetu. Trčci i mravi su se pokazali kao dobre grupe za redukciju brojnosti nekih korovskih biljaka, jer je utvrđeno da se neke njihove vrste hrane sjemenkama ovih štetočina. Pojedine vrste trčaka i mrava zabilježene u okviru istraživanoga lokaliteta mogu se koristiti u biološkoj borbi protiv određenih štetnih invazivnih biljaka.Rezultati istraživanja trebali bi pružiti osnovu za razvoj strategije za praćenje stanja i planiranje mjera za suzbijanje neželjenih biljnih vrsta radi zaštite autohtone flore. Samo pažljivo i odgovorno upravljanje prirodnim dobrom omogućit će da se broj invazivnih biljnih vrsta održi na postojećoj razini.SummaryThe main aim of the conducted research was to determine the presence of invasive plant species in the protected natural area of the Bojčin Forest Nature Monument. Floristic and vegetation study of the Bojčin Forest was conducted through several vegetation periods (from March 2009 to November 2011). The presence of 185 plant species recorded in the area of the Bojčin Forest reflects its flora richness. Out of the total number of recorded species, 31 taxa are listed as invasive plant species (Table 1), which makes 16.76% of the total flora of the Bojčin Forest Nature Monument. Among them, there are nine woody plant species and 22 herbaceous plant species. Among the tree species, Amorpha fruticosa L. should be particularly emphasized. It forms a thick shrub formation by the Jarčina Canal with reed [Phragmites australis (Cav.) Trin. ex Steud.] (Fig. 1). Also significant is the presence of the species Symphyotrichum lanceolatum (Willd.) Nesom, forming an edge of width of 4 m between forest and meadow where the all other plant species were repressed (Fig. 2). The greatest number of determined invasive plant species belong to the family Asteraceae (eight species), then to the families Fabaceae and Rosaceae (three species each), Amaranthaceae and Oxalidaceae (two species each), whereas the other families had a single invasive species each.During the 2011 year, insect fauna in the area of the Bojčin Forest was studied, with special emphasis on economically important species. It was found that the Bojčin Forest is inhabited by a total of 93 insect species. Among them, very significant are ground beetles (family Carabidae), especially some of them acting as predators of many insect pests. Ground beetles were registered in the Bojčin Forest with total of nine species and three subspecies. Three ant species were registered in the researched area of the Bojčin Forest. Some ground beetles and ants have been proved as a good group to reduce numbers of certain weed species, as they use seeds of these pests as the food. These insect species may be used in biological control of some harmful invasive plants.Research results should provide a basis for development of strategies for monitoring the state of unwanted species and planning measures of their reduction in order to protect the autochthonous flora. Only careful and responsible management of the natural area would maintain the abundance of these species at the current level