Phytomass stock estimation in larch ecosystems of Central Evenkia (on small watershed as a sample territory)

For the first time, on the basis of the data col-lected, in one of typical small pools in Central Evenkia the main types of larch forest types, their distribution depending on a relief have been re-vealed and general stocks of phytoweight in forest phytocenosis have been defined. The objects of the research were larch forest types (Larix gmelinii (Rupr.) Rupr.) ecosystems in the pool of the brook Kulingdakan (inflow of river Kochechum), about 4 240 hectares. The reservoir of the pool was limited from the North to heights of 412-627 m; from the South was 338-622 and 502-625 m n.u.m. - in the east. The stream, about 8 km long, has three in-flows and divides the water-collecting square in two approximately equal parts having northwest and southeast orientations. Having manufactured de-termination of the area and the pool in general was carried out on the basis of GIS-technologies. The exposition asymmetry in distribution of larch forest ecosystems on slopes of catchment basin was es-tablished. Rather warm and drained western slopes were occupied by the most productive larch eco-systems of green moss group (ledum red berry with Duschekia fruticosa, red berry ledum and ledum red berry lichen green moss). More cool and dry eastern slopes were covered with less productive larch ecosystems of green lichen and lichen groups (whortleberry ledum red berry and red berry crow-berry). Larch ecosystems with ledum whortleberry sphagnum and Betula nana and different Salix species on the damp with stagnant water depres-sions of the valley bottom were the lowest produc-tive phytocoenoses of the watershed. The richest in the stock components of larch forests in the region have been established to be the phytomass of ground vegetation (i.e. lichen moss cover with litter) and stem wood. Their phytomass on the model wa-tershed made 175895 t and 55582 t o.d.m. respec-tively. In the region with small watershed net the approach developed and the data obtained can be used for the monitoring of larch phytocenosis and vegetation cover as a whole.