Macrophytes distribution in the karstic river Rak and an assessment of the state of the aquatic system / Razporeditev makrofitov v kraški reki Rak in ocena stanja vodnega ekosistema

Authors

  • Darja Kopitar
  • Marija Kravanja
  • Aleksander Trajbarič
  • Mateja Germ Biotehniška fakulteta, Oddelek za biologijo, Večna pot 111, SI-1000 Ljubljana

DOI:

https://doi.org/10.3986/fbg0095

Keywords:

karst, macrophytes, RCE method, RMI, river Rak, kras, vodni makrofiti, RCE metoda, reka Rak

Abstract

The karst is a geographically and geologically highly dynamic area strongly dependent on water activity. This includes intermittent water bodies which have a specific impact on nearby environment. Sessile organisms such as plants have to adapt to extreme changes in water availability. Their presence, distribution and abundance can therefore serve as indicators of the ecological status of the water ecosystems. Using the modified Riparian, Channel, and Environmental (RCE) inventory method, we ranked the Rak River in the highest RCE quality classes. Based on the RMI (River Macrophyte Index), we classified the Rak River to good or very good ecological status. The good ecomorphological preservation of the Rak River probably also contributes to the presence of endangered plant species; among the 38 taxa listed, we detected the presence of eleven species included in Slovenian Red list of threatened pteridophytes and seed plants. At the time of our sampling, the species Zannichellia palustris was detected for the first time in this river. The high assessment of the preservation of the intermittent karst river Rak confirms the current good management and is important in the implementation of nature protection guidelines for the future.

 

IZVLEČEK

Kraški svet predstavljajo geografsko in geološko izjemno dinamična območja, ki so močno povezana z delovanjem vode. Presihajoča vodna telesa v kraškem svetu s svojim delovanjem močno vplivajo na okolje. V največji meri se morajo na velike spremembe dostopnosti vode prilagajati sesilni organizmi, kakršni so rastline. Njihova prisotnost, abundanca in razporeditev lahko služijo kot indikatorji stanja vodnih ekosistemov. S pomočjo prirejene metode RCE (ang. A Riparian, Channel, and Environmental Inventory) smo reko Rak uvrstili v najvišje RCE kakovostne razrede. Na osnovi indeksa RMI (ang. River Macrophyte Index) smo reko Rak uvrstili v dobro oz. zelo dobro ekološko stanje. Dobra ekomorfološka ohranjenost reke Rak verjetno botruje tudi pojavljanju ogroženih rastlinskih vrst; med 38 popisanimi taksoni smo zaznali prisotnost enajstih vrst, ki so uvrščene na Rdeči seznam ogroženih praprotnic in semenk. V času našega vzorčenja je bila v tej reki prvič zaznana vrsta Zannichellia palustris. Visoka ocena ohranjenosti presihajoče kraške reke Rak potrjuje dosedanje dobro upravljanje in je pomembna pri udejanjanju naravovarstvenih smernic za prihodnost.

Downloads

Published

2022-06-23

Issue

Section

Articles