Impact of different restoration methods on the zooplankton assemblage in the Adriatic coastal ponds

Zooplankton je važna komponenta biocenoza brojnih lentičkih ekosustava te je ujedno i izuzetan indikator promjena okolišnih čimbenika i ekološkog stanja. U hranidbenim mrežama ovih ekosustava zooplankton ima ključnu ulogu u prijenosu energije i hranjivih tvari od primarnih proizvođača do viših trofičkih razina. Antropogeni utjecaj i globalne klimatske promjene smanjuju bogatstvo plitkih vodenih tijela te se u svrhu njihovog očuvanja danas provode brojne restauracijske metode kako bi se održala i poboljšala njihova bioraznolikost. Stoga su ciljevi ovog rada bili: (i) usporediti strukturalni i funkcionalni sastav zooplanktona; (ii) utvrditi čimbenike koji određuju sastav zooplanktona; i (iii) odrediti stupanj trofije i ekološko stanje restauriranih plitkih vodenih tijela i onih bez primijenjenih restauracijskih metoda s izraženim antropogenim utjecajem u priobalnom jadranskom području. U devet lokvi determinirane su 42 vrste, a raznolikosti vrsta su najviše doprinijeli kolnjaci (26). Najveće brojnosti zooplanktona zabilježene su u lokvama na kojima je bila provedena redukcija makrofita, a najmanje brojnosti opažene su u lokvama bez primjene restauracijskih metoda. Značajan utjecaj na sastav zooplanktona imali su konduktivitet i koncentracija suspendirane organske tvari, kompleksnost građe makrofita te biomasa fitoplanktona. Rezultati ovog rada potvrđuju važnost pravilnog provođenja restauracijskih metoda u svrhu očuvanja bioraznolikosti i održavanja dobrog ekološkog stanja plitkih vodenih tijela.Zooplankton is an important component of the biocenoses in many lentic ecosystems and is also an ecceptional indicator of changes in environemntal variables and ecological status. In food webs, zooplankton is considered to have a key role in transfer of energy and nutrients from primary producers to higher trophic levels. Anthropogenic impact and global climate changes reduce the richness of shallow water bodies, and in order to preserve them, numerous restoration methods are being carried out. The main objectives of this study were: (i) to compare structural and functional composition of zooplankton; (ii) to indicate the factors that determine the composition of zooplankton; (iii) to determine trophy degree and ecological status of restored ponds and shallow water bodies without applied restoration methods with a pronounced anthropogenic influence of coastal Adriatic area. In nine ponds, 42 species were determined, and the diversity of species was mostly contributed by rotifers (26). The greatest abundance of zooplankton was observed in shallow lakes which were restored by macrophyte reduction, while the least abundance of zooplankton was observed in shallow water bodies without applied restoration methods. Conductivity, suspended organic matter concentration, complexity of macrophyte structure and phytoplankton biomass had a significant influence on the zooplankton comoposition. The results of this study confirm the importance of proper implementation of restoration measures in order to preserve biodiversity and maintain good ecological status of shallow water bodies