Characteristics of snowpack in major forest types of northern Daxinganling Mountains, northeastern China.

In order to explore the snowpack characteristics and their relationship associated to various forest types in northern Daxinganling Mountains of northeastern China, we observed snowfall amount, snowpack depth and density in and out of three main forest types from October to December, 2014. Based on the observation, we further calculated snow water equivalent (SWE) and interception rate and analyzed their features. The results indicated that: 1) the snow interception rate was closely related to forest types. Specifically, the snow interception rates increased with the upward level of snowfall for all three forest types. Regarding to the same amount of snowfall, the snow interception rates of different forest types were significantly different. Pinus sylvestris var. mongolica forest intercepted the maximum snowfall with a snow interception rate of 22.54% ,which was 1.9 times of Larix gmelinii forest, and 5.4 times of Betula platyphylla-Populus davidiana forest. 2) During the entire observation period, the forest type affected directly the snowpack depth. The snowpack depth in forest composed of evergreen species was lower than that in deciduous forest. The Larix gmelinii forest had the deepest snowpack of 27.92 cm while the Pinus sylvestris var. mongolica forest had the thinnest depth of 23.56 cm. 3) At the beginning of observation period, the snowpack density decreased due to the new snowfall inputting. But the snowpack density would increase when there was less or no snowfall input. The Larix gmelinii forest and Betula platyphylla-Populus davidiana forests showed quite similar variation of snowpack density while the Pinus sylvestris var. mongolica forest presented smaller variation than the other two forest types. 4) In entire observation period, the SWEs in different forest types showed significant differences (P 0.05). And the SWE in Pinus sylvestris var. mongolica forest was minimum with an amount of 26.49 mm, while the Betula platyphylla-Populus davidiana forests had the maximum SWE of 39.18 mm. In a word, the interception effect of different forest types was mainly influenced by forest canopy closure in winter and the latter also impacted the snowpack depth, density and consequent SWE directly.