Soil seed bank in black locust (Robinia pseudoacacia L.) stands at Medvednica Mt. and Maksimir park

Istraživanje je provedeno na području Parka prirode Medvednica i parka Maksimir unutar klimazonalne vegetacije običnog graba i hrasta kitnjaka, sa svrhom određivanja količine sjemenki bagrema u tlu i njihove vijabilnosti kao pokazatelja održanja sastojina bagrema. Odabrano je šest plohi površine 100 m² na temelju karte staništa PP Medvednice i rukopisnih vegetacijskih karti. Na plohama su prebrojane odrasle jedinke drveća, prikupljeni su uzorci tla i listinca u svrhu prebrojavanja dijaspora drvenastih vrsta te su prikupljeni uzorci tla kako bi odredili pH, količinu organske tvari, količinu humusa i postotak dušika. Sjemenke bagrema izolirane iz tla podvrgnute su testu klijavosti kako bi se ispitala njihova vijabilnost. Klijavost sjemenki bagrema iznosi 97 - 99 %, ovisno o ispitivanoj plohi. Potvrđena je banka sjemenki bagrema u tlu na istraživanim plohama i ona je iznosila 40 - 33800 sjemenki/m², pri čemu je zaključeno da bagrem ima komparativnu prednost u odnosu na banku sjemenki u tlu ostalih istraživanih vrsta.The research has been conducted in the area of Medvednica Nature Park and in Maksimir Park within the climazonal vegetation of common hornbeam and downy oak in order to determine locust tree seed quantity in the soil and its viability as an indicator of locust tree stand survival. Consequently, 6 areas covering 100m2 were selected based on the habitat map in Medvednica Nature Park and hand-written vegetation maps. Adult trees were counted throughout these areas, soil samples and dry leaves were collected in order to count the diaspora of ligneous species. In addition, soil samples were collected in order to calculate pH, organic substance quantity, quantity of humus soil and nitrogen percentage. Locust tree seeds isolated in the soil had to undergo a germination test to examine their viability. Locust tree seed germination stands at 97% - 99% depending on the area examined. Locust tree seed bank in the soil on the examined areas was identified and confirmed and it comprised of 40 - 33,800 seeds/m2, where it was concluded that locust had a comparative advantage over soil seed banks of other examined species