ИСТИНА

The Sea of Japan acts as an important environmental factor, developing the nature of the coastal land. Cold winds, constant high air humidity, fog, frequent drizzle, sea salt define particular qualities of the oak forests composition and structure. The height, diameter, lifetime of the oak (Quercus mongolica) – being an aedificator species – decrease with approach to the coast. The strongest influence of the sea affects the narrow up to 300 m belt, where the formative factor influences the forest stand to a great extent, transforming it to a shrub form, not typical to above species. Significant differences were specified also in grass layer structure of coastal zone woods. It become floristically and ecologically more diversified, compared to the continental ones, characterized by the presence of groups of plants, which are not normally typical to oak woods, such as halophytes, xerophytes, succulents. Within the zone from 300m to approx. 5 km inland the sea influence is saved, but weakly expressed, as evidenced by morphological parameters, while Quercus mongolica produce two-or-three trunk form. The sea universalizes the environmental conditions all over the coastal zone from the north to the south, making the grass cover of oak forests floristically similar to a high degree along latitudinal gradient. Behind the coastal zone environmental sea influence is negligible, the latitudinal position comes to the fore. Abovementioned data demonstrate the dominant role of the sea as a potent ecological factor, therefore could be applied while allocation of boundaries between marine and continental conditions.