Diverziteta in sestava perifitonske združbe kremenastih alg v reki Savi na območju Slovenije

Sušin, Tjaša (author), Zelnik, Igor (mentor)

Predmet raziskave je vpliv nadmorske višine in okoljskih dejavnikov na strukturo perifitonskih združb kremenastih alg v reki Savi od njenega izvira na Zelencih do Jesenic na Dolenjskem. Na devetih vzorčnih mestih smo vzorčili v zimskem (marec 2015) in poletnem (julij 2015) času. Na vsakem vzorčnem mestu smo ob vsakem vzorčenju nabrali 5-7 kamnov, s katerih smo pobrali 42 cm2 vzorca perifitona (epiliton) in z multimetrom izmerili določene abiotske dejavnike. Opazili smo tako časovno kot prostorsko spreminjanje parametrov, predvsem sta se spreminjali temperatura, nasičenost vode s kisikom in elektroprevodnost. V laboratoriju smo opravili kemijske analize.Ugotovili smo, da se vsebnost dušika (nitrat, amonij, totalni dušik) in fosforja (ortofosfat, totalni fosfor) dolvodno povečuje. V vzorcih perifitona smo skupno določili 118 različnih vrst kremenastih alg, najvišje število alg v vzorcu je bilo 48 (vzorec KK2). Najštevilčnejši sta bili vrsti Achnanthidium minutissimum in Achnanthidium pyrenaicum. Od Šentjakoba dolvodno se je v vzorcih pojavljala za perifiton neznačilna Cyclotella meneghiniana, najbolj pestro zastopani rodovi v vzorcih so bili Fragilaria, Navicula, Gomphonema, Nitzschia in Cymbella. Vrednosti trofičnega in saprobnega indeksa se dolvodno povečujejo in kažejo na to, da z oddaljenostjo od izvira postaja vodotok bolj obremenjen. Shannon-Wienerjev diverzitetni indeks je višji pozimi, v obeh letnih časih pa se povečuje dolvodno. Na sestavo združb vplivata predvsem temperatura in oddaljenost od izvira. Združbe, ki so bližje izviru so si bolj podobne.

• Language: Slovenian
• Keywords: perifiton/Sava/kremenaste alge/kakovost voda/diverziteta
• Work type: Master's thesis/paper
• Organization: BF - Biotechnical Faculty
• Year: 2017
• PID: 20.500.12556/RUL-99161
• COBISS.SI-ID: 4567631
• Publication date in RUL: 29.12.2017

SUŠIN, Tjaša, 2017, Diverziteta in sestava perifitonske združbe kremenastih alg v reki Savi na območju Slovenije [online]. Master’s thesis. [Accessed 14 April 2025]. Retrieved from: https://repozitorij.uni-lj.si/IzpisGradiva.php?lang=eng&id=99161

Secondary language

• Language: English
• Title: DIVERSITY AND STRUCTURE OF DIATOMS IN PERIPHYTON COMMUNITY IN THE SAVA RIVER IN SLOVENIA

Abstract

The main goal of the research was to investigate the influence of altitude and environmental factorson diatom periphyton communities composition in the Sava river from its source in Zelenci to Jesenice na Dolenjskem. We took winter (March 2015) and summer (July 2015) samples at nine locations. At each sampling site, we gathered 5–7 stones and sampled 42 cm2 periphyton (epilithon) altogether from the stones surfaces. Selected abiotic factors were measured, using the multi-meter. It was possible to observe that temporal and spatial parameters changed, especially temperature, oxygen saturation in water and conductivity. Chemical analyses were carried out in the laboratory and results showed that the content of nitrogen (nitrate, ammonium, total nitrogen) and phosphorus (orthophosphate, total phosphorus) is increasing downstream. In periphyton samples, 118 different species of diatoms were determined, with the highest number of algae species in the sample being 48 (sample KK2). The most abundant species were Achnanthidium minutissimum and Achnanthidium pyrenaicum. Cyclotella meneghiniana appeared in the samples downstream from the Šentjakob, what is untypical for the periphyton. The most diverse genera in the samples were Fragilaria, Navicula, Gomphonema, Nitzschia and Cymbella. The trophic and saprobic index values are increasing downwards and show that the river’s course becomes more congested by the distance from the source. The Shannon-Wiener (S-W) diversity index is higher in winter; however, it is increasing downstream in both seasons. The composition of the associations is primarily influenced by temperature and distance from the source. Associations which are closer to the source are more similar.

• Keywords: Periphyton/Sava/Bacillariophyceae/water quality/biodiversity