Publications by authors named "Takayuki Nakatsubo"

Pioneer mosses are among the dominant vegetation in the early stages of xeric successions. Recent climate warming may have a significant effect on the productivity of these mosses, thereby affecting successional processes. In this study, we investigated the effects of temperature changes on the productivity of Racomitrium japonicum, a pioneer moss species commonly found on open ground in Japan.

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*We examined the photosynthetic characteristics and net primary production of biological soil crusts to evaluate their contribution to the carbon cycle in the High Arctic glacier foreland. *Biological soil crust samples were collected from a deglaciated area in Ny-Alesund, Svalbard, Norway. Net photosynthetic rates (Pn) and dark respiration rates (R) of biological soil crusts were determined using CO(2) gas exchange rates.

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We examined factors controlling temporal changes in net ecosystem production (NEP) in a high Arctic polar semi-desert ecosystem in the snow-free season. We examined the relationships between NEP and biotic and abiotic factors in a dominant plant community (Salix polaris-moss) in the Norwegian high Arctic. Just after snowmelt in early July, the ecosystem released CO(2) into the atmosphere.

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Studies on terrestrial ecosystems in the high Arctic region have focused on the response of these ecosystems to global environmental change and their carbon sequestration capacity in relation to ecosystem function. We report here our study of the photosynthetic characteristics and biomass distribution of the dominant vascular plant species, Salix polaris, Dryas octopetala and Saxifraga oppositifolia, in the high Arctic tundra ecosystem at Ny-Alesund, Svalbard (78.5 degrees N, 11.

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The Arctic terrestrial ecosystem is thought to be extremely susceptible to climate change. However, because of the diverse responses of ecosystem components to change, an overall response of the ecosystem carbon cycle to climate change is still hard to predict. In this review, we focus on several recent studies conducted to clarify the pattern of the carbon cycle on the deglaciated area of Ny-Alesund, Svalbard in the high Arctic.

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The effects of climatic factors, especially those of temperature, on the carbon balance of the moss Sanionia uncinata were examined on King George Island in the maritime Antarctic. Net photosynthesis (P(n)) and dark respiration rates of two colonies (A and B) were measured with a portable infrared gas analyzer. Colony A showed small P(n) compared with its dark respiration rates throughout the growing season.

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