BIOLOGICAL PRODUCTIVITY OF <i>PICEA-ABIES</i> FORESTS IN EURASIA'S CLIMATIC GRADIENTS
It is found that biomass of spruce-fir forests increases monotonically according to zonal (natural) gradient with the exit to the plateau in the direction from the northern to the southern tip of Eurasia, and consistently reduced in the direction from the Atlantic and Pacific coasts to the continentality pole in Yakutia within a single zonal belt. Understory biomass has minimal value in the northern temperate zone, increasing in both northern and southern directions. Within a single zonal belt spruce-fir forest biomass continuously increases when approaching the pole of climate continentality. The ratio of underground biomass to aboveground one (root:shoot ratio) is reduced on zonal gradient from north to south. A similar decline occurs in the direction from the Atlantic and Pacific coasts to the pole of climate continentality within a single zonal belt. The ratio of understory biomass to total wood one is maximum in the subarctic zone, it dramatically reduces in the northern temperate zone, gradually increasing in the direction to the subequatorial belt. Within a single zonal belt the same ratio increases sequentially towards the pole of continentality. The regularities reported are obtained for the first time and are of a preliminary nature: as filling the database of forest biomass, using more sophisticated computational algorithms and due to climate change, they may be subject to changes.