Relation between soil salinity and species composition of halophytic plant communities: A baseline data inventory for wetland monitoring

Abstract

Our study sets forth the outcomes of an interdisciplinary project conducted in order to fill the information gap on the management of a wetland ecosystem, in the case of a protected area on the southeastern coast of Turkey. The hypothesis of the study is that the pattern of species composition reflects soil salinity level and some species can act as relevant indicators. The study aimed to discover a relationship between soil salinity and vegetation composition and establish some indicators useful for monitoring. For this aim, the temporal and spatial changes of soil salinity were monitored and the distribution of coastal habitats and associated plant communities were described. Twenty-three plant communities were described according to the species compositions of the vegetation. Soil salinity was found to be a driving factor controlling the spatial distribution of the plant taxa. The dominant species of the study area are Halocnemum strobilaceum, Arthrocnemum fruticosum, Spergularia marina, Plantago coronopus, and Atriplex portulacoides. The peak average annual salinity value, 1535 mS/m, was measured in a pure stand of H. strobilaceum. A high significant positive correlation was determined between plant species richness and life form richness. Strong evidence was detected for species richness, which declines at higher salinity habitats and there is also some evidence that species turnover is greater among the 52 sampling quadrates. Eleven distinct habitats were determined.

Ecophysiological and Biochemical Responses Depicting Seed Tolerance to Osmotic Stresses in Annual and Perennial Species of Halopeplis in a Frame of Global Warming

“…Accordingly, some authors demonstrated a greater salt tolerance in the germination phase for annual plants than in perennials and explained it in terms of their pioneer character, differences in the habitat colonized and the ability to complete the life cycles rapidly in an unpredictable environment [82]. In contrast, other authors identified annuals as the most sensitive to salinity [1], with stress escaping strategies [83,84]. Our results are in accordance with latter findings as they show a higher tolerance in the perennial H. perfoliata than in the annual H. amplexicaulis.…”

“…Salt-affected habitats are complex environments in which subtle changes in ecological factors determine plant occurrence, communities' richness and distribution [1]. In this sense, differences in levels of germination success linked to salt tolerance and biotic interactions during seedling emergence and establishment are important in plant composition and salt marsh zonation patterns [2].…”

“…Water/osmotic stress caused by a decrease in osmotic potential under salinity and drought inhibits various plant processes, especially seed germination that determines plants dispersal and abundance [1,4]. In addition to osmotic effect, salinity stress leads to an accumulation of ions, which can produce ionic stress [4].…”