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Knjiga se bavi znanstvenim aspektom Plitvičkih jezera kroz geologiju, hidrologiju, kemiju i najvećim dijelom biologijom.

Plitvička jezera predstavljaju jedinstveni slatkovodni kaskadni sustav jezera odijeljenih sedrenim barijerama. U ovom radu istražen je utjecaj modificiranih podloga koje otpuštaju hranjive soli dušika (N) i fosfora (P) na makrozoobentos, klorofil a i količinu sedre. Replikatne podloge postavljene su u Nacionalnom parku Plitvička jezera na izlaznim sedrenim barijerama Gradinskog jezera (GJ) i Novakovića brod (NB) u svakom godišnjem dobu tijekom 2015. godine. Vrijednosti fizikalno-kemijskih i hidroloških pokazatelja lotičkih biotopa razlikuju se između barijera uz značajne razlike po godišnjim dobima. Intenzivnije osedravanje zabilježeno je na barijeri NB u odnosu na GJ. Fosfor se izdvojio kao limitirajući čimbenik za primarnu proizvodnju. Povišene koncentracije klorofila a zabilježene su na barijeri GJ i na mikrolokacijama bez makrovegetacije, a istu dinamiku pratila je i povišena brojnost i broj svojti makrozoobentosa te povišena brojnost hranidbenih skupina strugača i detritivora-sakupljača. Brojnost makrozoobentosa povišena je na podlogama s dodanim hranjivim solima fosfora. Plitvice lakes represent the unique freshwater cascading system of lakes divided by tufa barriers. This thesis investigates the influence of nutrient diffusing substrates that release nitrogen (N) and phosphorus (P) on macrozoobenthos, chlorophyll a and tufa deposition. Replicate substrates were placed in the Plitvice Lakes National Park on the tufa barriers of Gradinsko jezero lake outlet (GJ) and Novakovića brod lake outlet (NB) in every season during 2015. The values of the physico-chemical and hydrological indicators on lotic biotopes were different between barriers with significant differences between seasons. Higher tufa deposition was recorded on the NB barrier compared to GJ barrier. Phosphorus was the limiting factor for primary production. Higher concentrations of chlorophyll a were recorded on the GJ barrier and at microlocations without macrovegetation, followed by the same dynamic in higher abundance and number of macrozoobenthic taxa and feeding groups of scrapers and detritvores-collectors. The abundance of macrozoobenthos was higher on the substrates with added phosphorus.

Tufa depositing environments create myriad of microhabitats for periphyton. Precipitation of calcite may increase heterogeneity, but it can also present a certain stress for periphyton. Different crevices in tufa and undersides of rocks might present less changing environment. The aim of this study was to determine dynamics of tufa deposition and periphyton development on artificial substrates (glass slides) facing upwards (U) and downwards (D) within tufa- depositing sites. The experiment was conducted in situ on tufa barrier Skradinski buk (Croatia) from June to September 2014 with sampling after one month of exposition. Tufa deposits were about four-foldhigher on substrates facing upwards than downwards (averagely 3.9 vs. 0.5 mg CaCO3/cm2), and there was about three-fold more organic matter on U compared to D substrates. However, diversity of protozoa and micro-metazoa was higher on D (85 taxa) compared to U substrates (65 taxa) likely due to more favorable microhabitat. Ciliates had the highest taxa numbers (51 on D and 41 on U substrates) as well as highest share in abundance (92% and 88%, respectively). Sessile forms prevailed among ciliates, having a share of 96% (D substrates) and 97% (U substrates) in abundance. Suctorians dominated on U substrates, while peritrichs had highest share in abundance on D substrates. Both groups probably utilize plenty of food flowing over the barrier from upstream Visovačko Lake, as tufa barriers in this system also function as lake outlets. Endemic folliculinid ciliate Lagotia dinaridica colonized only substrates facing downwards.

Dinamika razgradnje dvaju vrsta listinca (lopuh Petasites spp. i bukva Fagus sylvatica L.)praćena je metodom „vrećica listinca“ u razdoblju od prosinca 2006. do studenog 2007. godine, na dvjema sedrenim barijerama Plitvičkih jezera. Na svakoj postaji eksperiment je proveden u tri vremenske serije na dva reotopa (brza i spora struja vode). Također su analizirane kemijske promjene samog listinca i okolne vode, taloženje sedre na listincu i promjena mase kockica sedre smještenih u vrećice s raspadajućim listincem. Na brzinu razgradnje listinca utječe brzina strujanja vode, temperatura vode i stopa osedravanja, osim u početnoj fazi razgradnje. Utjecaj osedravanja na brzinu razgradnje pokazao se različit za dvije vrste listinca: nakon duže izloženosti i pod utjecajem spore struje uz visok intenzitet taloženja sedre, osedravanje je čak djelovalo inhibitorno na razgradnju bukve, dok je isti proces ubrzavao razgradnju brzoraspadajućeg lopuha. Proces razgradnje listinca uglavnom potiče taloženje sedre osim u početnoj fazi taloženja kalcita (do 30 dana) ili pri manjem intenzitetu osedravanja, kad je zabilježeno otapanje sedre. Decomposition dynamics of two types of litter (butterbur Petasites spp. and beech Fagus sylvatica L.) was analysed in the period from December 2006. to November 2007. on two tufa barriers of Plitvice Lakes. Experiments using leaf bags were carried out in three time series on two rheotopes (fast and slow current velocity) on each barrier. Chemical changes of the litter and the surrounding water were also analysed, as well as tufa deposition on litter surface and weight changes of tufa cubes embedded in the bag with the decaying litter. Litter decomposition rates were dependent on current velocity, water temperature and tufa deposition rate, except in the initial stage. The effect of tufa deposition on the litter decomposition rate proved to be different for the two types of litter: after prolonged exposure to calcification and under the influence of slow currents in combination with high tufa deposition rate, it even acted inhibitory on the decomposition of beech, while the same process accelerated decomposition of fast-decomposing butterbur. Leaf litter decomposition mainly accelerates tufa deposition with the exception of the initial stage of calcite deposition (up to 30 days) or at lower intensity of calcification, when dissolution of tufa was noticed.