Increasing sea levels and anthropogenic disturbances have caused the world’s coastal vegetation to decline 25-50% in the past 50 years. Future sea level rise (SLR) rates are expected to increase, further threatening coastal habitats. In combination with SLR, the Everglades ecosystem has undergone large-scale drainage and restoration changing Florida’s coastal vegetation. Everglades National Park (ENP) has 21 coastal plant species threatened by SLR. My dissertation focuses on three aspects of coastal plant community change related to SLR and dehydration. 1) I assessed the extent and direction coastal communities—three harboring rare plant species—shifted from 1978 to 2011. I created a classified vegetation map and compared it to a 1978 map. I hypothesized coastal communities transitioned from less salt- and inundation-tolerant to more salt- and inundation-tolerant communities. I found communities shifted as hypothesized, suggesting the site became saltier and wetter. Additionally, all three communities harboring rare plants shrunk in size. 2) I evaluated invading halophyte (salt-tolerant) plant influence on soil salinity via a replacement series greenhouse experiment. I used two halophytes and two glycophytes (non-salt-tolerant) to look at soil salinity over time under 26 and 38‰ groundwater. I hypothesized that halophytes increase soil salinity as compared to glycophytes through continued transpiration during dry, highly saline periods. My results supported halophytic influence on soil salinity; however, not from higher transpiration rates. Osmotic or ionic stress likely decreased glycophytic biomass resulting in less overall plant transpiration. 3) I assessed the best plant life-stage to use for on-the-ground plot-based community change monitoring. I tested the effects of increasing salinity (0, 5, 15, 30, and 45‰) on seed germination and seedling establishment of five coastal species, and compared my results to salinity effects on one-year olds and adults of the same species. I hypothesized that seedling establishment was the most vulnerable life-stage to salt stress. The results supported my hypothesis; seedling establishment is the life-stage best monitored for community change. Additionally, I determined the federally endangered plant Chromolaena frustrata’s salinity tolerance. The species was sensitive to salinity >5‰ at all developmental stages suggesting C. frustrata is highly threatened by SLR.

PAPER The possibilities of naturalization of rare and vanishing plants’ species are surveyed in master’s study The subject of research - The botanical gardens of Liskiava with the rare and vanishing plants’ species cultured and naturalized there. Objective of the research – Naturalized species of the plants: Turk’s-cap (Lilium martagon), medicinal angelica (Angelica archangelica), perennial satinflower (Lunaria rediviva), and ivy bedstraw (Hedera helix). Also the naturalization in site of rare plants is observed and estimated. Methods of study – Some studied plants were brought from their natural vegetation places, digging out it with the thickness of soil, some of then were sown from seeds: macro bloom finger-flower (Digitalis grandiflora), meadowy salvia (Salvia pratensis). The naturalization of these plants and capability to proliferate is also observed. Ecologist of Dzukija National park, Henrikas Gudavicius conduced to pursue the observation and researches, also rendered comprehensive information about the botanical gardens of Liskiava. Such possibilities of naturalization of rare and vanishing plants’ species were no studied in Lithuania. The conclusion could be done under the results of research: rare plants can be naturalized, just the proper place must be chosen and the observation is necessary during the first year. Keywords: National park of Dzukija, The botanical gardens of Liskiava, rare and vanishing plants’ species, naturalization.