Lake Cerknica is the locus typicus of intermittent lakes and one of the most important wetlands in Slovenia. One of the key habitat-forming species in its littoral zone and riparian belt is common reed (Phragmites australis), which forms extensive dense stands, while comparable areas are also occupied to a lesser extent by reed canary grass (Phalaris arundinacea). In this doctoral dissertation, we examined the effects of hydrological conditions on vegetation composition, productivity related and morphological traits, and physiological and biochemical stress indicators in stands of both species during the 2023 growing season. For common reed, we additionally assessed the effect of mowing in relation to hydrological conditions. In 2024, we developed a method for mapping marsh vegetation using remote sensing data and multi output regression modelling with artificial neural networks. For common reed, mowing, both in the previous year and through its cumulative effect over the previous four years, outweighed the influence of hydrological conditions on reed stand vitality. Based on functional characteristics, reed stands were divided into three groups: structurally closed stands with high productivity and low species richness, frequently mown heterogeneous stands with high species richness and low primary production, and encroaching stands in which mowing inhibits succession towards woody vegetation. For reed canary grass, no statistically significant differences were detected between riparian and littoral stands. The developed workflow enabled accurate mapping of reed fractions (MAE = 0.07, RMSE = 0.10, R² = 0.87), while comparison with the 2017–2023 mowing map further confirmed the effect of mowing on reed stand vitality. The results highlight the key role of mowing in shaping reed stand structure and vitality and demonstrate the usefulness of remote sensing for mapping heterogeneous marsh vegetation.
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