Chemical Dynamics of Snow Cover and Snow Biology

点击翻译按钮获取中文摘要

A study was carried out at a boreal fores, eastern Canada. Conentrations of NH _4 ^+ and NO _3 ^- of precipitation in a forest are lower than that in a open area. The losses of NH _4 ^+ and NO _3 ^- are considered to be affected by the biological activity. Concentration of chemical substance of snowmelt water in a open area shows diurnal variation. The hydrograph of snowmelt is separated into "old water" and "new water". Meltwater in the lower snowpack is called to "old water", and meltwater percolated from surface snow layr is called to "new water". The separated "old water" is the major componentof early snowmelt runoff. "New water" is the major component of recession limb of the hydrograph.Seasonal change of surface impurities covering a perennial snow patch, Kuranosuke sekkei in Japan Alps, were analyzed. During the thawing period, amount and coloin darkness of the impurities gradually increased and bulk albedo of the snow patch was reduced in accordance with it. Microscopic observation and albedo spectrum of the impurities revealed that drkening of the impurity coloration was mainly due to the growth of cryo-microbes such as snow algae, fungi and bacteria growing in the melting snow.In some Himalayan glaciers, the microbial production on the glacier surface is so large during the monsoon that the surface of the ablation area is covered with a dark clored mud-like material which mainly consists of algae and bacteria. This material reduces the surface albedo of glacier and accelerates glacier melting.