Regular Changes in Soil Moisture Content in Coniferous Forests of the Udyly State Nature Reserve, Lower Amur River Region

Landscape–ecological studies have been conducted on 25 sampling plots in the low-mountain part of the Udyly State Nature Reserve occupied by larch and spruce–fir forests. Data on the soil moisture content, soil temperature, and characteristics of phytocoenoses have been collected to identify patterns in their spatial changes. This paper presents the results of a soil moisture content analysis. A comparison of data on the soil moisture content with topographic attributes performed using the multiple regression method show that topographic factor explains 59–78% of the moisture content variance. Changes in soil moisture content are determined by the position in the catena, distance from the coast of the Sea of Okhotsk, and distinct features of curvature flows. The moisture content variance increases from 73 to 82% if other factors (i.e., soil temperature, soil granulometric composition, and characteristics of groups of phytocoenoses) are used as spatial variability predictors in addition to topographic attributes. Still, the successful validation of models based solely on topographic attributes makes it possible to produce soil moisture content matrices that can be used to construct probabilistic maps of phytocoenotic characteristics.