Salicornia prostrata Pall. and Suaeda prostrata Pall. subsp. prostrata occur together on saline soils in Kızılırmak Delta in Samsun, Turkey. The effects of salinity stress on photosynthetic pigments and proline were investigated in these two species in natural habitats. With the increasing soil salinity, a decrease in chlorophyll (Chl) and carotenoid contents was observed in both taxa. However, in Salicornia prostrata, photosynthetic pigments levels were lower than those in Suaeda prostrata. Proline contents significantly increase with increase in salinity level in both species, whereas Salicornia prostrata produced less proline than Suaeda prostrata. Proline and Chl a contents were significantly different betweesn examined species according to soil salinity. Based on obtained data, we can conclude that at in situ conditions, Salicornia prostrata is more salt tolerant compared with Suaeda prostrata.

A salt-tolerant population of Salicornia freitagii Yaprak and Yurdakulol (naturally adapted) from saline soils of Bahşili village, Sungurlu, Ç orum, Turkey, was evaluated for root and succulent stem modifications. Salttolerant populations from low (2.3 dS m-1), medium (20.7 dS m-1) and highly (46.3 dS m-1) saline soils were collected for comparisons. Decreased parenchyma in roots is critical for enhancing water loss. However, the thickness of parenchyma in roots of S. freitagii collected from the edge of the stream was not more affected by the increase in salinity levels. Stem anatomical characters as thickness, length and width of water-storing tissue significantly increased in highly saline environments. The thickness of xylem and the diameter of the vessels decreased at higher salinity. There was an increase in the diameter of pith in stem with increasing salt levels. Additionally, it was observed that stomatal index was considerably reduced under high salinity. Our results report root and stem anatomical features of S. freitagii resulting from adaptation to salinity stress.

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The aim of this study is to reveal the syntaxonomical structure of Tavşan Mountain in the Euxinian transition area in northern Turkey. Eight plant associations were determined and classified using the Braun-Blanquet phytosociological approach. Detrended correspondence analysis was also used to reveal the environmental heterogeneity among the plant associations. Raunkiaer life form ratios of syntaxa were calculated. Shannon-Wiener index values also were determined for each plant association. The results of this study suggested that which environmental factors could be decisive in community diversity and syntaxonomical status.