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The trunk is not only the largest biomass storage in forest ecosystems, but also long-term and huge carbon sink. Trunk organization of living cells throughout the year during carbon metabolism, breathing lead to the photosynthetically fixed a large number of CO2 is released into the atmosphere, thus affecting the carbon balance of forest ecosystems. As one of the main components of the forest ecosystem autotrophic respiration, stem respiration, not only can be indicative of tree growth, vitality and carbon metabolism, the more effect on the productivity of the forest ecosystem. Is located in the middle and high latitudes, sensitive to climate change in the northeast temperate forests in sustaining an important role in the carbon balance of terrestrial ecosystems and the carbon cycle in one of the uncertainties is the size of the woody tissue respiration, but in this regard The research is not, in particular, the lack of quantitative Stem respiration intraspecific and interspecific variation. Infrared gas analyzer - local flux assay June to October 2009 and from May to November 2010, in situ determination of 14 and 12 temperate forest trunk of the main tree species of the eastern mountains of northeast surface CO2 flux ( RW), aims to quantify the kinds of intra-and inter-RW, annual flux (RT) and its components (growth respiration, RG) differences, explore the change in diameter of the RW, RT, RG with trees and Rw monthly flux (RM ) The seasonal dynamics of the law, for in-depth understanding of the carbon cycle of temperate forest ecosystems, build, and verify the model to provide the basic data. The determination of the species include: diffuse porous wood and broad-leaved ((birch Betula platyphylla), Maple Leaf B. costata, Populus tremula Populus davidiana, purple linden Tilia amurensis, Pentagon maple Acer mono), ring-porous wood and semi-ring-porous wood broad-leaved trees (Ulmus Ulmus propinqua, yellow pineapple Phellodendron amurense, (Juglans mandshurica Juglans mandshurica), Mongolian oak, Quercus mongolica in the ash Fraxinus mandshurica), conifers (Larix Larch Larix gmelinii, Korean pine, Pinus koraiensis, the Redskins spruce, Picea koraiensis, Pinus sylvestris P. sylvestris var. mongolica). Species, month, and their interactions significantly affect the RW (P lt; 0.001). 2009 measurement period of 14 species average RW volatility 1.32 (yellow pineapple)-3.12μmol CO2 m-2 s-1 (Larix gmelinii) between the ring-porous wood and semi-ring-porous wood broadleaf average RW diffuse porous wood broadleaf trees, conifers Rw variation. Rw absolute intraspecific variation (standard error, SE) fluctuations between 0.11-0.29μmol CO2 · m-2 · s-1, the relative variability (coefficient of variation, CV) fluctuations in 61% (Picea koraiensis) -89 % (birch). Seasonal variation patterns of the average showed a single peak of each species Rw, in July, the highest, lowest in October. RW have of each species with a diameter at breast height (DBH) increases an increasing trend, but the regression model and its coefficient of determination between species. The Ulmus and Ash (P gt; 0.05), the Rw and DBH of the other species of the regression relationship between significant (P lt; 0.05), push some species Rw forecasts and show that DBH can be used as a simple Useful indicators. 2010 12 species RT and RG intraspecific and interspecific differences significant (alpha = 0.05), average RT and RG fluctuations 144.13 (pine) -628.08 GC · m-2 · a-1 (Quercus mongolica) and 27.24 (pine) -153.27 gC m-2 · a-1 (Ash), ring porous wood species were higher than RT and RG diffuse porous wood trees and conifers. Absolute RT and RG intraspecific variation (standard deviation, SD) fluctuations in 67.07 (pine) -320.20 GC · m 2 · a-1 (Quercus mongolica) and 18.86 (pine) -90.19 gC · m- 2 · a-1 (Quercus mongolica), CV fluctuations between 40% (yellow pineapple) -68% (aspen) and 38% (Tilia amurensis) -79% (Quercus mongolica). RM of each species showed a peak in June and July unimodal pattern of seasonal variation. RT and RG of each species were with DBH increases an increasing trend, but the difference between the regression model and its coefficient of determination with the species change. In addition to outside the yellow pineapple (RT) and ash (RG) (P gt; 0.05), the regression relationship between RT and RG DBH of the remaining species was significantly (P lt; 0.05), show that DBH can be used as the estimate of a some species RT and RG is a simple and practical indicators. Annual or growing season, the RG contribution of each species were less than 50%, indicating that maintenance respiration during the growing season and throughout the year a larger proportion may be offset by the growth of the growth. This study emphasizes the importance of measurement should take full account of intraspecific differences between the estimate in the trunk comparison of the ability to breathe and.
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