Stuies on the carbon- and mineral- cycling under changing enviromment Larix forests of Far East Asia

研究了远东多年冻土区南缘落叶松森林流域与生长、演替和碳储量相关的碳、水和矿物循环。研究地点为：a)中国哈尔滨东北林业大学北部毛尔山实验林业中心（季节性冻土区），b)中国大兴安岭，c)中国最北端漠河，d)俄罗斯阿穆尔河地区布拉格别杰斯克（不连续多年冻土区）。地点c)和d)反复受到森林火灾的影响。对阿穆尔河北部山区连续多年冻土区的落叶松林进行了调查。“落叶松森林的分布与永久冻土层的存在密切相关，而永久冻土层几乎没有被森林和湿地的存在所保护。”如果全球变暖或森林火灾破坏了森林覆盖或湿地，该地区的永久冻土很容易消失，导致永久冻土内部或上方积累的有机物释放出二氧化碳和甲烷。大兴安岭有机碳储量分布不均，特别是在湿地和（或）地下，从全球变暖的角度说明了该地区保护湿地的重要性。在黑龙江地区火灾后自然更新的森林中，落叶松、栎（栎）、桦树（白桦、白桦）、松（松）、杨树（白杨）等树种具有较高的多样性。落叶松在森林火灾后具有同步再生和空间集中分布的特点。反复的森林火灾被认为是这种类型更新的驱动力，通过烧毁森林地面上的树苗和/或幼树，以及该地区森林火灾对种子树的广泛破坏。

The carbon-, water- and mineral cycling were investigated in the Larix forest watersheds, associated with growth, succession and carbon storage, of southern limit area of permafrost region of Far East Asia. The research sites were set in the Larix (Larix gmelinii) forests of a) Maoershan Experimental Forestry Center, north Northeast Forestry University, Harbin, China (seasonally frozen area), b) the Greater Khingan Range, China, c) Mo-he, northernmost of China and d) Blagobeshensk, Amur Region, Russia (discontinuous permafrost region). The site c) and d) were affected by the forest fires repeatedly. The Larix forests in continuous permafrost area also investigated in northern mountain range in Amur region.'The distribution of Larix forest was strongly related to the presence of Permafrost layers which were barely preserved by the existence of forests and wet lands. The permafrost in this region is likely to disappear easily if forest cover or wet land were destroyed by global warming or forest fires, which results in the release of CO2 together with methan from accumulated organic substances inside or above permafrost. The organic carbon storage in the Great Khingan Range showed uneven distribution especially in and /or under wet land, which indicated the importance of the preservation of wet land in this area from the aspect of global warming.In the naturally regenerated forests after forest fire of Amur region, they exhibited high diversity of tree species such as Larix, oak (Quercus mongolica), birch (Betula platyphylla, Betula davurica), pine (Pinus sylvestris), aspen (Populus tremula) etc. Larix was estimated to regenerate simultaneously and make spatially concentrated distribution after forest fire. Repeated forest fire was considered to be the driving force of this type of regeneration through burning off the saplings and/or the young stands on the forest floor in addition to the extensive destruction of seed trees by forest fires in this region.