长白山典型阔叶红松林土壤二氧化碳排放通量

随着大气CO2浓度的升高,主要由其引起的温室效应与对生物新陈代谢的影响变得越来越显著。森林生态系统在全球碳循环中扮演着重要的角色。为了评估和理解森林土壤CO2通量及其随空气和土壤温度的季节和昼夜变化规律,我们在长白山北坡典型阔叶红松林内利用静态箱技术进行了原位观测。实验在整个生长季(6月初至9月末)昼夜进行,利用气相色谱进行气体分析。结果表明: 长白山阔叶红松林土壤是大气二氧化碳源,其CO2通量具有明显的季节和昼夜变化规律。通量的变化范围是(0.30-2.42)μmol穖-2穝-1,平均值为0.98μmol穖-2穝-1。土壤CO2排放的季节规律表明,土壤CO2通量的变化与气温和土壤温度的变化有关。CO2平均通量的最大值出现在7月((1.27±23%)μmol穖-2穝-1),最小值出现在9月((0.5±28%)μmol穖-2穝-1)。土壤CO2的昼夜波动与土壤温度变化有关,而在时间上滞后于温度的变化。森林下垫面土壤CO2通量与土壤温度显著相关,与6cm深度土层温度相关系数最大。基于气温和土壤温度计算的Q10值范围为2.09-3.40。图2表3参37。     

Effects of soil moisture and temperature on CH4 oxidation and N2O emission of forest soil

Soil samples were taken from depth of 0–12 cm in the virgin broad-leaved/Korean pine mixed forest in Changbai Mountain in April, 2000. 20 μL·L⁻¹ and 200 μL·L⁻¹ CH₄ and N₂O concentration were supplied for analysis. Laboratory study on CH₄ oxidation and N₂O emission in forest soil showed that fresh soil sample could oxidize atmospheric methane and product N₂O. Air-dried soil sample could not oxidize atmospheric methane, but could product N₂O. However, it could oxidize the supplied methane quickly when its concentration was higher than 20 μL·L⁻¹. The oxidation rate of methane was increased with its initial concentration. An addition of water to dry soil caused large pulse of N₂O emissions within 2 hours. There were curvilinear correlations between N₂O emission and temperature (r²=0.706, p<0.05), and between N₂O emission and water content (r²=0.2968, p <0.05). These suggested temperature and water content were important factors controlling N₂O emission. The correlation between CH₄ oxidization and temperature was also found while CH₄ was supplied 200 μL·L⁻¹ (r²=0.3573, p<0.05). Temperature was an important factor controlling CH₄ oxidation. However, when 20 μL·L⁻¹ CH₄ was supplied, there was no correlation among CH₄ oxidization, N₂O emission, temperature and water content. Foundation item: This paper was supported by Chinese Academy of Sciences. Biography: ZHANG Xiu-jun (1960-), female, Ph. Doctor, lecture in Laboratory of Ecological Process of Trace Substance in Terrestrial Ecosystem, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110015, P.R. China. Responsible editor: Song Funan     

Response of seedlings of different tree species to elevated C02 in Changbai Mountain

Eco-physiological responses of seedlings of eight species,Pinus koraiensis, Picea koraiensis, Larix olgensis, Populus ussuriensis, Betula platyphylla, Tilia amurensis, Traxinus mandshurica andAcer mono from broadleaved/Korean pine forest, to elevated CO₂ were studied by using open-top chambers under natural sunlight in Changbai Mountain, China in two growing seasons (1998–1999). Two concentrations of CO₂ were designed: elevated CO₂ (700 μmol·mol⁻¹) and ambient CO₂ (400 μmol·mol⁻¹). The study results showed that the height growth of the tree seedlings grown at elevated CO₂ increased by about 10%–40% compared to those grown at ambient CO₂. And the water using efficiency of seedlings also followed the same tendency. However, the responses of seedlings in transpiration and chlorophyll content to elevated CO₂ varied with tree species. The broad-leaf tree species were more sensitive to the elevated CO₂ than conifer tree species. All seedlings showed a photosynthetic acclimation to long-term elevated CO₂. Foundation item: The project was supported by National Key Basic Development of China (G1999043400) and the grant KZCX 406-4, KZCX1 SW-01 of the Chinese Academy of Sciences Biography: WANG Miao (1964-), maie, associate professor in Institute of applied Ecology, Chinese Academy of Sciences, Shenyang 110016, P. R. China. Responsible editor: Song Funan     

长白山两种森林类型土壤颗粒有机碳和黑碳分布特征

[目的]量化长白山原始阔叶红松林和杨桦次生林土壤颗粒有机碳和黑碳含量及分布特征,为研究东北森林土壤有机碳分布和积累提供依据。[方法]采用粒径分组方法测定原始阔叶红松林和杨桦次生林土壤表层(A_(11))和亚表层(A_(12))颗粒有机碳(POC)和黑碳(BC)含量,分析其与土壤基本性质(有机质、含水量、p H值、粘粒和团聚体等)的关系。[结果]表明:(1)两种森林类型土壤A_(11)和A_(12)POC含量分别为31.89 88.00、5.25 19.45 g·kg~(-1),BC含量分别为8.43 22.40、3.39 12.10 g·kg~(-1),二者随土壤深度增加而显著下降(p0.01)。(2)森林类型显著影响土壤POC和BC,表现为杨桦次生林原始阔叶红松林。(3)两种森林类型土壤POC与土壤有机质、含水量、水稳性团聚体均显著相关,与p H值、粘粒相关性不显著;BC与土壤p H值、粘粒和团聚体相关性均不显著,与含水量显著相关,与有机质仅在A_(11)显著相关。(4)土壤POC和BC显著相关(p0.01)。[结论]在长白山地区森林类型显著影响土壤POC和BC含量,杨桦次生林土壤POC和BC显著高于原始阔叶红松林,很大程度上与森林的采伐和火烧有关。两种森林类型土壤POC和BC分布格局是土壤物理化学性质综合作用的结果。     

Photosynthetic response ofPinus sylvestriformis to elevated carbon dioxide and its influential factor analysis

The photosynthetic response of 12-year oldPinus sylvestriformis to elevated CO₂ and its influential factors were tested and analyzed in the forest region of Changbai Mountain in 1999. Trees grown at the natural condition were controlled at three levels of CO₂ concentration (350 μL·L⁻¹, 500 μL·L⁻¹ and 700 μL·L⁻¹) by CO₂ rich settlement designed by us. Net photosynthetic rates (NPR), temperature, relative humidity, stomatal conductance, intercellular CO₂ concentration and photosynthetic active radiation (PAR) were measured at 6:00, 8:00, 10:00, 14:00, 16:00 and 18:00 hours a day. Experimental results showed that the NPR ofPinus sylvestriformis increased by 32.6% and 123.0% at 500 μL·L⁻¹ and 700 μL·L⁻¹ CO₂ concentration respectively, compared to ambient atmospheric CO₂ concentration (350 μL·L⁻¹). The relations between NPR and influential factors, including temperature, relative humidity, intercellular CO₂ concentration and photosynthetic active radiation, were analyzed respectively by regression analysis at different CO₂ concentrations. Foundation Item: This project was supported by Chinese Academy of Sciences. Biography: WANG Chen-rui (1970-), male, Assistant Research Fellow in Institute of Applied Ecology, Chinese Academy of Sciences. Responsible editor: Chai Ruihai     

Temperature controls temporal variation in soil CO2 efflux in a secondary beech forest in Appi Highlands, Japan

Forest soil is a huge reserve of carbon in the biosphere. Therefore to understand the carbon cycle in forest ecosystems, it is important to determine the dynamics of soil CO₂ efflux. This study was conducted to describe temporal variations in soil CO₂ efflux and identify the environmental factors that affect it. We measured soil CO₂ efflux continuously in a beech secondary forest in the Appi Highlands in Iwate Prefecture for two years (except when there was snow cover) using four dynamic closed chambers that automatically open after taking measurements. Temporal changes in soil temperature and volumetric soil water content were also measured at a depth of 5 cm. The soil CO₂ efflux ranged from 14 mg CO₂ m⁻² h⁻¹ to 2,329 mg CO₂ m⁻² h⁻¹, the peak occurring at the beginning of August. The relationship between soil temperature and soil CO₂ efflux was well represented by an exponential function. Most of temporal variation in soil CO₂ efflux was explained by soil temperature rather than volumetric soil water content. The Q ₁₀ values were 3.7 ± 0.8 and estimated annual carbon emissions were 837 ± 210 g C m⁻² year⁻¹. These results provide a foundation for further development of models for prediction of soil CO₂ efflux driven by environmental factors.     

Functional evaluation for effective compositions in seed oil of Korean pine

The effect of seed oil of Korean pine (Pinus koraiensis) on the rats’ blood-fat and its anti-ageing function was studied for appraising the efficacy of the seed oil of Korean pine. Sixty experimental rats were randomly divided into 5 groups (half males and half females in each group) as normal control group, high fat diet control group, and three groups (Group 1 Group 2, Group 3) that were fed with feedstuff with the contents of the seed oil of 2.0g/(kg·d⁻¹), 4.0g/(kg·d⁻¹) and 8.0g/(kg·d⁻¹), respectively. The indexes such as superoxide dismutase (SOD), glutathione peroxidase (GSH-PX) and anti-oxidation capacity (AOC) were measured by Reagent Kit method. It was found that the seed oil of the Korean pine could reduce the content of triglyceride and improve SOD as well as GSH-PX activity in serum. These indexes of the rats in Group 2 fed with Korean pine seed oil of 4.0 g/(kg·d⁻¹) reached the significant level and those of rats in Group 3 fed with the seed oil of 8.0 g/(kg·d⁻¹) reached the extremely significant level. The results indicated the seed oil of Korean pine had function of regulating the level of blood-fat and anti-ageing. Biography: WANG Zhen-yu (1957-), male, Prof. in Forestry College, Northeast Forestry University, Harbin 150040, P. R. China. Responsible editor: Zhu Hong     

Temperature sensitivity of soil CO2 production in a tropical hill evergreen forest in northern Thailand

Tropical forests, like boreal forests, are considered key ecosystems with regard to climate change. The temperature sensitivity of soil CO₂ production in tropical forests is unclear, especially in eastern Asia, because of a lack of data. The year-round variation in temperature is very small in tropical forests such that it is difficult to evaluate the temperature sensitivity of soil CO₂ production using field observations, unlike the conditions that occur in temperate and boreal forests. This study examined the temperature sensitivity of soil CO₂ production in the tropical hill evergreen forest that covers northern Thailand, Laos, and Myanmar; this forest has small temperature seasonality. Using an undisturbed soil sample (0.2 m diameter, 0.4 m long), CO₂ production rates were measured at three different temperatures. The CO₂ production (SR, mg CO₂ m⁻² s⁻¹) increased exponentially with temperature (T, °C); the fitted curve was SR = 0.023 e^0.077T, with Q₁₀ = 2.2. Although still limited, our result supports the possibility that even a small increase in the temperature of this region might accelerate carbon release because of the exponential sensitivity and high average temperature.     

造纸废渣和养分的改良对北部硬阔叶林土壤表面CO2通量的影响

Safe and economical disposal of paper mill sludge is a key consideration for forest products industry. A study was conducted to examine the effects of amendments of sludge and nutrients on soil surface CO₂ flux (R_s) in northern hardwood forests and to quantify the relat among R₅, soil temperature, and moisture in these stands. The experiment was a randomized complete block design that included sludge-amended, fertilized, and control treatments in sugar maple (Acer saccharum Marsh) dominated hardwood forests in the Upper Peninsula of Michigan, USA. Results showed that R_s was positively correlated to soil temperature (R²=0.80, p<0.001), but was poorly correlated to soil moisture. Soil moisture positively affected the R_s only in the sludge-amended treatment. The R_s was significantly greater in the sludge-amended treatment than in the fertilized (p=0.033) and the control (p=0.048) treatments. The maximum R_s in the sludge-amended treatment was 8.8 μmol CO₂·m⁻²·s⁻¹, 91% and 126% greater than those in the fertilized (4.6 μmol CO₂·m⁻²·s⁻¹) and control (3.9 μmol CO₂·m⁻²·s⁻¹) treatments, respectively. The R_s did not differ significantly between the fertilized and control treatments. The difference in R_s between sludge-amended and the other treatments decreased with time following treatment. Foundation item: The research was funded by a NCASI grant to S.T. Gower. Wang CK was supported by Innovated Talent Program of Northeast Forestry University (2004–07) Biography: WANG Chuan-kuan (1963-), male, Professor in the Ecology Program, College of Forestry, Northeast Forestry University, Harbin 150040, China. Responsible editor: Chai Ruihai     

The contribution of root respiration of<Emphasis Type="Italic">Pinus koraiensis</Emphasis> seedlings to total soil respiration under elevated CO<Subscript>2</Subscript> concentrations

The impacts of elevated atmospheric CO₂ concentrations (500 μmol·mol⁻¹ and 700 μmol·mol⁻¹) on total soil respiration and the contribution of root respiration ofPinus koraiensis seedlings were investigated from May to October in 2003 at the Research Station of Changbai Mountain Forest Ecosystems, Chinese Academy of Sciences, Jilin Province, China. After four growing seasons in top-open chambers exposed to elevated CO₂, the total soil respiration and roots respiration ofPinus koraiensis seedlings were measured by a Li-6400-09 soil CO₂ flux chamber. Three PVC cylinders in each chamber were inserted about 30 cm into the soil instantaneously to terminate the supply of current photosynthates from the tree canopy to roots for separating the root respiration from total soil respiration. Soil respirations both inside and outside of the cylinders were measured on June 16, August 20 and October 8, respectively. The results indicated that: there was a marked diurnal change in air temperature and soil temperature at depth of 5 cm on June 16, the maximum of soil temperature at depth of 5 cm lagged behind that of air temperature, no differences in temperature between treatments were found (P>0.05). The total soil respiration and soil respiration with roots severed showed strong diurnal and seasonal patterns. There was marked difference in total soil respiration and soil respiration with roots severed between treatments (P<0.01); Mean total soil respiration and contribution of root under different treatments were 3.26, 4.78 and 1.47 μmol·m⁻²·s⁻¹, 11.5%, 43.1% and 27.9% on June 16, August 20 and October 8, respectively. Foundation item: This study was supported by the Knowledge Innovation Project of the Chinese Academy of Sciences (KZCX1-SW-01) and the National Natural Science Foundation of China (30070158). Biography: LIU Ying (1976-), female, Ph. D. Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, P. R. China. Responsible editor: Song Funan     

Photosynthetic induction responses of Pinus koraiensis seedlings grown in different light environments

The time processes of photosynthetic induction responses to various irradiances in Korean pine (Pinus koraiensis) seedlings grown in open-light environments and in understory of forest were studied in an area near the Research Station of Changbai Mountain Forest Ecosystems, Jilin Province, China from July 15 to August 5, 1997. The results showed that at 200 μmol·m⁻²·s⁻¹ photosynthetic photon flux density (PPFD) and 500 μmol·m⁻²·s⁻¹ PPFD, the induction time for the photosynthetic rates of understory-grown seedlings to reach 50% and 90% steady-state net photosynthetic rates was longer than that of the open-grown seedlings. The induction responses of open-growth seedlings at 500 μmol·m⁻²·s⁻¹ PPFD were slower than those at 200 μmol·m⁻²·s⁻¹ PPFD, but it was the very reverse for understory-growth seedlings, which indicates that the photosynthetic induction times of Korean pine seedlings grown in the understory depended on the sunfleck intensity. Biograph: ZHOU Yong-bin (1970-), female, associate professor of Shenyang Agricultural University, Shenyang 110161, P.R. China. Responsible editor: Song Funan     

非生长季刺槐林土壤CH4通量的变化特征及其影响因子

[目的]探讨在非生长季不同天气条件下45年生刺槐林土壤CH₄通量的日变化和季节变化特征,并确定其主要影响因子.[方法]2014年10月-2015年4月(非生长季),在华北低山丘陵区黄河小浪底森林生态系统定位研究站,利用基于离轴积分腔输出光谱技术的土壤CH₄通量自动观测系统,对土壤CH₄通量进行连续观测,同步观测林内大气温度和相对湿度、5 cm深处土壤温度和土壤湿度、林内总辐射以及降雨量,分析各因子间的相互关系并确定影响土壤CH₄通量的主要因子.[结果]表明:(1)在非生长季,刺槐人工林土壤为大气CH₄重要的汇,变化范围为-0.15~-2.34 nmol·m^-2·s^-1 .晴天的林地土壤吸收CH₄能力 (-0.78 nmol·m^-2·s^-1) 明显高于阴天(-0.61 nmol·m^-2·s^-1)、降雨或降雪天气 (-0.58 nmol·m^-2·s^-1),而且呈"V"型日际变化特征;在2014年11月-2015年1月,土壤吸收CH₄能力逐渐下降,并维持相对较低的水平,直至2015年3月达到最大值 (-2.34 nmol·m^-2·s^-1);(2)土壤CH₄通量与大气温度、5 cm深处土壤温度呈显著负相关,与相对湿度呈正相关;在2015年1月,土壤CH₄通量与总辐射呈正相关;(3)在生长末期土壤上冻阶段和冬季土壤冻结阶段,大气温度和相对湿度为影响土壤CH₄通量的主要因子;而在生长季初期,主要的影响因子为大气温度和5 cm深处土壤温度.[结论]非生长季刺槐林土壤表现为大气CH₄的汇,在非生长季初期土壤吸收CH₄的能力最弱,主要受大气温度和相对湿度的影响,而在非生长季末期土壤吸收CH₄的能力逐渐增加,主要受大气温度和土壤温度的影响.     

土壤温度和水分对长白山3种温带森林土壤呼吸的影响

为了研究土壤温度和土壤含水量对阔叶红松林(山地暗棕壤)、云冷杉暗针叶林(山地棕针叶林土壤)和岳桦林(生草森林土)的土壤呼吸的影响,于2001年9月在长白山进行了土壤实验。利用增加土壤样柱的含水量,将土壤含水量分为9%,、21%、30%、37%和43%5个等级,土壤样品分别在0、5、15、25和35的温度下保持24小时。阔叶红松林土壤在0~35范围内,土壤呼吸速率与温度呈正相关。在一定的含水量范围内(21%~37%),土壤呼吸随含水量的增加而升高,当含水量超出该范围,土壤呼吸速率则随含水量的变化而降低。土壤温度和水分对土壤呼吸作用存在明显的交互作用。不同森林类型土壤呼吸作用强弱存在显著差异,大小顺序为阔叶红松林>岳桦林>云冷杉暗针叶林.红松阔叶林土壤呼吸作用的最佳条件是土壤温度35,含水量37%;云冷杉暗针叶林下的山地棕色针叶土壤呼吸作用的最佳条件是25,21%;岳桦林土壤呼吸作用的最佳条件是35,含水量37%。但是,由于长白山阔叶红松林,云冷杉林和岳桦林处在不同的海拔带上,同期不同森林类型土壤温度各不相同,相差4~5,所以野外所测的同期的山地棕色针叶林土呼吸速率应低于暗棕色森林土呼吸速率,山地生草森林土呼吸速率应高于山地棕色针叶林土的呼吸速率。图2表1参25。     

温度对大叶桃花心木(Swietenia macrophylla King)幼苗叶片的光合影响

本文研究了大叶桃花心木（Swietenia macrophylla King）一年生幼苗在经过夜温处理后的光响应曲线和在饱和光强下的CO2反应曲线.结果表明:在大气CO2浓度下,叶片的最佳光合作用温度在25-31℃之间,而在饱和CO2浓度下为31-35℃.在25℃以下光合速率开始降低,主要是由于羧化效率的降低,而当温度超过31℃时,光合速率下降,是因为羧化效率的降低和呼吸速率的增加.CO2浓度对光合的促进作用在低温下受到抑制,这意味着未来在CO2浓度增高的情况下,高浓度的CO2对热带常绿植物光合的促进在冬天低温情况下表现不十分明显.图4参23.     

Moisture and soil texture effects on soil CO2 efflux components in southeastern mixed pine forests

Monitoring soil CO₂ efflux rates and identifying controlling factors, such as forest composition or soil texture, can help guide forest management and will likely gain relevance as atmospheric CO₂ continues to increase. We examined soil CO₂ efflux and potential controlling factors in managed mixed pine forests in southwestern Georgia. Soil CO₂ efflux was monitored periodically in two stands that differed in soil texture in 2001 and 2002, and in six additional stands in 2003. We also monitored controlling factors: soil temperature, moisture, organic layer mass, and A layer depth. Soil moisture and CO₂ efflux varied with soil texture differences among the stands. As expected, soil temperature had a strong influence on soil CO₂ efflux. Soil moisture, organic layer mass, and A layer depth also were correlated with soil CO₂ efflux during periods of water stress, but these relationships differed with soil texture. Forest management activities can alter components of soil CO₂ efflux, including soil carbon pools, temperature, and moisture; understanding the underlying variation of these components and resultant CO₂ efflux over soil types can help guide management toward desired forest carbon balance trends in southeastern mixed pine forests.     

CO2 fluxes of a Scots pine forest growing in the warm and dry southern upper Rhine plain, SW Germany

The effects of the warm and dry weather in the southern upper Rhine plain in the southwest of Germany on the carbon balance of the Scots pine forest at the permanent forest meteorological experimental site Hartheim were analysed over a 14-month period. The investigation of the net ecosystem exchange of carbon dioxide (F _NEE) of the Scots pine forest started in the extraordinary hot and dry August 2003. Carbon dioxide fluxes were measured continuously using an eddy covariance system and analysed by use of the EDDYSOFT software package. After determining the temperature dependence of the forest ecosystem respiration and the daytime light dependence of the CO₂ exchange, monthly and annual carbon balances of the Scots pine forest were calculated. Mean peak daytime F _NEE rates observed in August and September 2003 (−6.5±3.6 μmol m⁻² s⁻¹) were drastically lower than in August and September 2004 (−11.8±5.2 μmol m⁻² s⁻¹), which did not show pronounced deviations from the mean long-term (1978–2002) climatic conditions. In August 2003, the Hartheim Scots pine forest was a distinct CO₂ source (35 g C m⁻²). The estimates of the annual carbon sink strength of the Scots pine forest ranged between −132 g C m⁻² (August 2003–July 2004) and −211 g C m⁻² (October 2003–September 2004). The main uncertainty in the determination of the carbon balance of the Hartheim Scots pine forest was introduced by the frequently low turbulence levels, i.e. the friction velocity corrected night-time F _NEE fluxes.     

白桦光合特性的研究

测定了3年生白桦的光合与呼吸作用对温度,湿度以及CO2浓度的响应;还测定了光补偿点,光饱和点和CO2补偿点。结果表明:在目前的空气CO2浓度下,光合和呼吸作用的最适温度分别是24℃和30℃;当相对湿度是80%时,白桦能维持较强的光合作用;呼吸作用与相对湿度无明显的相关性;光补偿点和光饱和点分别是25 molm-2s-1和1375 祄olm-2s-1;CO2补偿点是180 礚L-1;白桦在CO2浓度为2400 礚L-1时仍有吸收潜力。图4参19。     

德国中部Soiling云杉-山毛榉混交林冠层组成对土壤CO2排放的影响

It was hypothesized that soil respiration can be affected by canopy composition. Hence, admixture of trees as a common forest management practice may cause significant change in the carbon cycling. This study was conducted in a mixed spruce-beech stand at Solling forest in central Germany to investigate the effect of canopy composition on soil respiration. The canopy cover was classified in four major canopy classes (pure beech, pure spruce, mixed and gap), and the area under each canopy class was identified as a sub-plot. Soil respiration in each sub-plot (n=4) was measured monthly from Jun 2005 to July 2006. Results show significant difference in annual soil respiration between the beech (359 g·m⁻²·a⁻¹ C) and gap (211 g·m⁻²·a⁻¹ C) sub-plots. The estimation of the total below-ground carbon allocation (TBCA) based on a model given by Raich and Nadelhoffer revealed considerably higher root CO₂ production in the beech sub-plot (231 g·m⁻²·a⁻¹ C) compare to the gap sub-plot (51 g·m⁻²·a⁻¹ C). The contribution of the root respiration to the total soil respiration was higher in the soil under the beech canopy (59%) compared with the soil in the gap (29%). The findings suggested that the condition under the beech canopy may cause more desirable micro-site for autotrophic respiration and consequently higher CO₂ release into the atmosphere.     

A new methodology for estimating forest NPP based on forest inventory data—A case study of Chinese pine forest

Accurately estimating forest net primary productivity (NPP) plays an important role in study of global carbon budget. A NPP model reflecting the synthetic effects of both biotic (forest stand age, A and stem volume, V) and climatic factors (mean annual actual evapotranspiration, E) was developed for Chinese pine (Pinus tabulaeformis) forest by making full use of Forest Inventory Data (FID) and dynamically assessing forest productivity. The NPP of Chinese pine forest was estimated by using this model and the fourth FID (1989–1993), and the spatial pattern of NPP of Chinese pine forest was given by Geography Information System (GIS) software. The results indicated that mean NPP value, of Chinese pine forest was 7.82 t m⁻²·a⁻¹ and varied at the range of 3.32–11.87 t hm⁻²·a⁻¹. NPP distribution of Chinese pine forests was significantly different in different regions, higher in the south and lower in the north of China. In terms of the main distribution regions of Chinese pine, the NPPs of Chinese pine forest in Shanxi and Shaanxi provinces were in middle level, with an average NPP of 7.4 t hm⁻²·a⁻¹, that in the southern and the eastern parts (e.g. Shichuang Hunan, Henan, and Liaoning provinces) was higher (over 7.7 t hm⁻²·a⁻¹), and that in the northern part and western part (e.g. Neimenggu and Ningxia provinces) was lower (below 5 t hm⁻²·a⁻¹). This study provides an efficient way for using FID to understand the dynamics of foest NPP and evaluate its effects on global climate change. Foundation item: This study was supported by the National Natural Science Foundation of China (Nos. 30028001, 49905005), National Key Basic Research Specific Foundation (G1999043407); the Chinese Academy of Sciences (KSC2-1-07). Biography: ZHAO Min (1973-), female, Ph. D. in Laboratory of Quantitative Vegetation Ecology, Institute of Botany, the Chinese Academy of Sciences, Beijing 100093, P. R. China. Responsible editor: Zhu Hong     

长白山阔叶红松林CO2廓线和CO2贮存的动态

从1999年8至10月,2000年的4至6月,2002年8月至2003年9月,在平均树高为26米的长白山阔叶红松林内,用红外气体分析仪(2250D,LI-CORInc.和LI-COR,820)测定了不同高度的二氧化碳浓度。根据测定的数据,分析了阔叶红松林二氧化碳廓线的日变化和季节变化动态。结果表明:CO2浓度的垂直分布在白天和夜间是不同的,在接近地面处CO2浓度始终最大。从季节CO2廓线看出,在植物生长季节林冠处CO2浓度有明显的成层现象,不同高度(60~2.5m)的CO2浓度3月份变化较小差值为10mmol穖ol-1,而在7月份变化较大,差值为60mmol穖ol-1。7月份林冠处(22,26,32m)CO2浓度梯度较大,浓度差为8mmol穖ol-1。计算位于涡度相关仪器之下的40米高空气柱中CO2贮存状况表明,年际贮存是负值,但对NEE的贡献很小。图4参11。