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1.
采用2 km ×2 km的UTM网格取样法对广东省东莞市8个主要森林类型的植被碳库、凋落物碳库和土壤碳库等三大碳库的有机碳储量和碳密度进行了计量、比较分析和评价.结果表明:东莞森林碳储量总量为973.05 ×104 t,森林总平均碳密度为175.86 t·hm-2;其中森林植被总碳储量为161.48 × 104t,平均...  相似文献   

2.
不同杨-农间作模式碳储量及分布的比较   总被引:3,自引:0,他引:3  
采用生物量法对杨农复合生态系统中3种不同间作模式各组分的碳含量、碳储量及整个系统碳储量进行比较研究.结果表明;在K,P及W 3种模式中,深度为1 m的土壤碳含量变化范围0.64~15.27 g·kg~(-1),土壤碳储量分别达71.19,40.67和42.64 t·hm~(-2);杨树不同器官中碳含量仅细根和毛细根与其他器官存在显著差异,但碳储量树干所占比例最高,3种模式中分别占到49.7%,50.8%,51.2%;4种间种作物中小麦、玉米、大豆、水稻根的碳含量均明显低于其他器官,碳储量都为收获部分(穗或豆荚)所占比例最大,小麦、玉米、大豆均达50%左右,水稻为45%左右,但3种模式农作物均以小麦+玉米的年耕作制度的碳储量最大;3种模式中,凋落物归还碳量分别为(0.78±0.23),(0.73±0.22)和(O.37±0.09)t·hm~(-2)a-(-1);杨农复合生态系统碳储量均是土壤>农作物>杨树>凋落物,但整个系统的碳储量为K模式>W模式>P模式.  相似文献   

3.
以杨树纯林和杨农复合林2种生态系统为研究对象,对林木、农作物(林下植被)、土壤、凋落物各组分的碳储量进行比较研究。结果表明,杨树纯林和杨农复合林的碳储量分别为(101.59±8.1),(116.65±10.3)t/hm2。在2个生态系统中林木及土壤碳储量均占总量的90%以上。杨农复合林凋落物和林下植被碳储量所占比例约为6%,是杨树纯林的2倍。林木碳储量、农作物(林下植被)碳储量均为杨农复合林较高;杨农复合林土壤碳储量仅在中间层(10~25,25~50 cm)显著高于杨树纯林;凋落物碳储量2者之间差异不显著。相对纯林,农林复合系统具有较高的吸收和固碳能力。  相似文献   

4.
毛竹、杉木人工林生态系统碳平衡估算   总被引:4,自引:0,他引:4  
采用CID-301PS光合测定仪,对湖南会同林区毛竹和杉木人工林土壤CO2排放动态进行观测,并结合现存生物量调查,对其生态系统碳平衡特征进行估算.结果表明:毛竹和杉木林生态系统碳贮量分别为144.3和152.52 t·hm-2,并且其碳贮量空间分布格局基本一致,土壤层是主要部分,其次为乔木层,凋落物层和林下植被层所占比例最小.毛竹林土壤层有机碳贮量占76.89%,乔木层占22.16%,凋落物和林下植被层分别占0.51%和0.41%;杉木林土壤层碳贮量占62.03%,乔木层占34.99%,凋落物和林下植被层分别占2.28%和0.70%.毛竹林和杉木林生态系统年固定CO2总量分别为38.87和26.95 t·hm-2a-1,但其每年以土壤异养呼吸和凋落物呼吸的形式排放CO2的量分别为24.35和15.75 t·hm-2a-1,毛竹林和杉木林生态系统年净固定CO2的量分别为14.52和11.21 t·hm-2a-1,折合成净碳量分别为3.96和3.07 t·hm-2a-1.  相似文献   

5.
九龙江口秋茄红树林储碳固碳功能研究   总被引:1,自引:0,他引:1  
以福建九龙江口24年生、48年生的秋茄红树林为研究对象,通过测定秋茄林木层各器官、凋落物层、土壤层含碳率和土壤呼吸,结合各组分生物量和年净生产量,计算秋茄红树林的碳储量和年净固碳量。结果表明:24年生、48年生秋茄林碳储量分别为183.31、244.45 t·hm-2,其中林木层碳储量分别为162.45、222.95 t·hm-2,凋落物层碳储量分别为15.05、16.99 t·hm-2,土壤层和林木层碳储量在生态系统碳储量中的比例均随林龄增大而升高。24年生、48年生秋茄林均表现出了碳汇功能,其中24年生秋茄林年净固碳量较大,为18.51 t·hm-2·a-1;而48年生秋茄林的碳汇功能较低,为7.01 t·hm-2·a-1。  相似文献   

6.
利用大量生物量实测数据及历年森林资源统计数据,对黑龙江省南瓮河自然保护区碳储量及各碳库分布进行定量研究。结果表明:南瓮河自然保护区碳储量为1 567.1×104 t。其中植被碳储量为903.4×104 t,占总储量的58%;土壤碳储量为606.3×104 t,占总储量的41%;枯落物碳储量为17.4×104 t,占总储量的1%。各分碳库储量中,棕针土土壤碳库、乔木层碳库、草本层碳库为主要碳库,占总储量的89%。  相似文献   

7.
在黄土丘陵区选择从耕地、草地、灌木林到乔木林样地,不同样地内设立1 m × 1 m(乔木10 m×10 m)的样方,分析样方内凋落物积累量、碳氮含量、土壤有机碳(SOC)和可溶性碳(DOC)含量变化.结果表明:天然草地、灌木林、乔木林凋落物积累量依次为5.3,12.1和32.4 t·hm-2;但人工灌木林和乔木林的凋落物积累量分别为6.7和11.4 t·hm-2,分别是天然灌木林和乔木林的1/2和1/3.随着植被的恢复,天然植被凋落物的C/N高于人工植被(刺槐林除外).与耕地SOC(4.67 g·kg-1)相比,天然灌木林地SOC提高5.9倍,人工灌木林地提高1.8倍;天然乔木林地提高8.0倍,而人工乔木林地仅提高4.0倍.凋落物积累量与0~20 cm土层土壤有机碳存在显著线性相关关系(R2>0.83),但20 cm以下线性相关关系不显著.凋落物积累量与0~10 cm土壤可溶性碳含量存在显著线性相关关系(R2>0.893),与10~60 cm土层线性相关关系不显著,与80~100 cm土壤可溶性碳存在显著线性负相关关系.  相似文献   

8.
中国亚热带5种林分凋落物层植硅体碳的封存特性   总被引:1,自引:0,他引:1  
【目的】森林生态系统的植硅体碳是一种长期(数千年)封存的土壤有机碳,对全球固碳有重要意义。本研究旨在估测中国亚热带森林凋落物层的植硅体碳贮量。【方法】以中国亚热带5种常见林分类型(毛竹林、杉木林、马尾松林、阔叶林和针阔混交林)的凋落物为研究对象,收集地表凋落物并采集0~10 cm 土层土样,用微波消解法提取凋落物及土壤中的植硅体,并测定植硅体中的碳含量。【结果】不同森林凋落物 SiO2含量表现为毛竹林(152.50 g·kg -1)>阔叶林(13.96 g·kg -1)>针阔混交林(12.55 g·kg -1)>杉木林(7.62 g·kg -1)>马尾松林(6.59 g·kg -1);凋落物植硅体含量表现为毛竹林(180.20 g·kg -1)>阔叶林(14.67 g·kg -1)>针阔混交林(11.49 g·kg -1)>马尾松林(11.36 g·kg -1)>杉木林(5.58 g·kg -1);凋落物中植硅体碳含量表现为毛竹林(4.34 g·kg -1)>阔叶林(1.07 g·kg -1)>针阔混交林(1.04 g·kg -1)>马尾松林(0.67 g·kg -1)>杉木林(0.50 g·kg -1);凋落物现存生物量表现为阔叶林(3.20 kg·m -2)>马尾松林(2.51 kg·m -2)>针阔混交林(2.38 kg·m -2)>杉木林(1.88 kg·m -2)>毛竹林(1.45 kg·m -2); 5种林分凋落物中的 SiO2含量与植硅体含量极显著正相关(R2=0.9405,P <0.01);植硅体含量与植硅体碳含量(R2=0.9500,P <0.01)以及植硅体碳中有机碳含量与凋落物中植硅体碳含量(R2=0.7018,P<0.01)均极显著相关;毛竹林、杉木林、马尾松林、阔叶林和针阔混交林凋落物层中的植硅体碳贮量分别为0.231,0.034,0.062,0.125和0.090 tCO2·hm -2;毛竹林、杉木林、马尾松林、阔叶林和针阔混交林 0~10 cm 土层的植硅体碳贮量分别为0.492,0.217,0.352,0.362和0.448 tCO2·hm -2。【结论】5种林分均能通过凋落物植硅体将植硅体碳封存到土壤中;毛竹林凋落物中植硅体碳含量、凋落物和土壤的植硅体碳贮量在5种林分中都表现为最高;若以中国亚热带毛竹林年凋落物量3.6 t·hm -2 a -1计算,毛竹林凋落物的植硅体碳封存速率为0.057 tCO2·hm -2 a -1。本研究得到的中国亚热带中 5种林分凋落物的植硅体碳贮量数据为进一步评价中国亚热带森林生态系统植硅体碳封存潜力提供科学依据。  相似文献   

9.
湖北省太子山森林植被碳密度及碳储量研究   总被引:1,自引:0,他引:1  
以湖北省太子山林场管理局2009年森林二类清查数据资料为基础,运用生物量转换因子连续函数法,从森林类型、林龄和林分起源角度,对该区域森林植被碳储量和碳密度进行估测.研究表明:湖北省太子山林管局森林植被碳储量为233855.66 t,平均植被碳密度为39.31 t·hm^-2.人工林碳储量高于天然林4.02倍,该区域森林植被碳储量主要由人工林提供.按森林类型划分,不同森林类型碳储量和碳密度均表现为针叶林>阔叶林>针阔混交林;按林龄划分森林碳储量,幼龄林>成熟林>中龄林>近熟林>过熟林,各林龄碳密度随林龄的增加表现为先增加后降低的趋势,中幼林森林面积和碳储量所占比例较大,该区域森林植被碳储量潜力巨大.  相似文献   

10.
自然因子对中国森林土壤碳储量的影响分析   总被引:3,自引:0,他引:3  
文中分析了森林植被、土壤属性、立地条件、气候条件以及凋落物和根系输入等自然因素对中国森林土壤碳储量的影响。森林植物种类组成决定了进入土壤的植物残体量和分解速率,导致土壤有机碳的含量及分布有很大差异。随着林龄的增加,土壤碳储量会呈现增加或产生波动2种情况。土壤理化性质影响土壤有机碳的含量,而土壤碳储量又影响着土壤结构、根系深度、土层特性、有效水分保持能力、土壤生物多样性等; 海拔、坡度、坡向、坡位等立地条件对森林土壤有机碳储量的影响各不相同; 温度、水分、CO2浓度等气候因子在森林土壤有机碳的蓄积过程中起着至关重要的作用; 凋落物和根系对土壤的输入也可以改变土壤碳库。  相似文献   

11.
阔叶红松林倒木贮量动态研究   总被引:4,自引:2,他引:4  
代力民  李扬等 《林业研究》2002,13(2):107-110
本文研究了中国吉林省长白山区阔叶红松林倒木贮量的动态变化规律。阔叶红松林倒木贮量包括其现有倒木及其年输入量等贮量的变化规律。阔叶红松林现有倒木贮量开始为16.25 t·hm-2,以后随时间减少,到100年分解掉其干重的85%左右,300年后所剩无几。倒木年输入量平均约为0.6 t·hm-2,其贮量是随时间而增加,200年后稳定在31 t·hm-2,可保持到该群落的顶级时期。倒木总贮量的变化在初期呈增加趋势,而后随着现有倒木的完全分解,倒木贮量就与其倒木的年输入趋于一致,最后稳定在上述水平上。图4表2参9。  相似文献   

12.
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  相似文献   

13.
Hurricanes cause abrupt carbon reduction in forests, but silviculture treatment can be an effective means of quickly regenerating and restoring hurricane-damaged sites. This study assessed how silviculture treatments affect carbon balance after hurricane damage in central Hokkaido, Japan. We examined carbon storage in trees and underground vegetation as well as carbon emissions from silviculture operations in 25-year-old stands, where scarification and plantation occurred just after hurricane damage. The amount of carbon stored varied according to silviculture treatment. Among three scarification treatments, a scarified depth of 0 cm (understory vegetation removal) led to the largest amount of carbon stored (64.7 t·ha-1 C). Among four plantation treatments, the largest amount of carbon was stored in a Larix hybrid (L. gmelinii var. japonica × L. kaempferi) plantation (80.3 t·ha-1 C). The plantation of Abies sachalinensis was not successful at accumulating carbon (40.5·ha-1 C). The amount of carbon emitted from silviculture operations was 0.05-0.14 t·ha-1 C, and it marginally affected the net carbon balance of the silviculture project. Results indicate that silviculture treatments should beperformed in an appropriate way to effectively recover the ability of carbon sequestration in hurricane-damaged forests.  相似文献   

14.
Using the multi-temporal Landsat data and survey data of national resources, the authors studied the dynamics of cultivated land and landcover changes of typical ecological regions in China. The results of investigation showed that the whole distribution of the cultivated land shifted to Northeast and Northwest China, and as a result, the ecological quality of cultivated land dropped down. The seacoast and cultivated land in the area of Yellow River Mouth expanded by an increasing rate of 0.73 km·a−1, with a depositing rate of 2.1 km·a−1. The desertification area of the dynamic of Horqin Sandy Land increased from 60.02% of the total land area in 1970s to 64.82% in 1980s but decreased to 54.90% in early 1990s. As to the change of North Tibet lakes, the water area of the Namu Lake decreased by 38.58 km2 from year 1970 to 1988, with a decreasing rate of 2.14 km2·a−1. Foundation Item: This paper was supported by National Natural Science Foundation of China (Grant No. 39900084) and KZCX1-10-07. Biography: ZHANG Jia-hua (1966-), male, Ph. Doctor, Associate professor in START, Institute of Atmospheric Physics, Chinese Academy of Sciences. Responsible editor: Chai Ruihai  相似文献   

15.
The Dahurian larch forest in northeast China is important due to its vastness and location within a transitional zone from boreal to temperate and at the southern distribution edge of the vast Siberian larch forest. The continuous carbon fluxes were measured from May 2004 to April 2005 in the Dahurian larch forest in Northeast China using an eddy covariance method. The results showed that the ecosystem released carbon in the dormant season from mid-October 2004 to April 2005, while it assimilated CO2 from the atmosphere in the growing season from May to September 2004. The net carbon sequestration reached its peak of 112 g·m−2·month−1 in June 2004 (simplified expression of g (carbon)·m−2·month−1) and then gradually decreased. Annually, the larch forest was a carbon sink that sequestered carbon of 146 g·m−2·a−1 (simplified expression of g (carbon)·m−2·a−1) during the measurements. The photosynthetic process of the larch forest ecosystem was largely affected by the vapor pressure deficit (VPD) and temperature. Under humid conditions (VPD < 1.0 kPa), the gross ecosystem production (GEP) increased with increasing temperature. But the net ecosystem production (NEP) showed almost no change with increasing temperature because the increment of GEP was counterbalanced by that of the ecosystem respiration. Under a dry environment (VPD > 1.0 kPa), the GEP decreased with the increasing VPD at a rate of 3.0 μmol·m−2·s−1·kPa-1 and the ecosystem respiration was also enhanced simultaneously due to the increase of air temperature, which was linearly correlated with the VPD. As a result, the net ecosystem carbon sequestration rapidly decreased with the increasing VPD at a rate of 5.2 μmol·m−2·s−1·kPa−1. Under humid conditions (VPD < 1.0 kPa), both the GEP and NEP were obviously restricted by the low air temperature but were insensitive to the high temperature because the observed high temperature value comes within the category of the optimum range.  相似文献   

16.
A study was conducted to test the correlation between biomass and elevation and the differences in concentration and storks of nutrients among five vegetation types (Felsenmeer alpine tundra vegetation-FA, Lithic alpine tundra vegetation-LA, Typical alpine tundra vegetation-TA, Meadow alpine tundra vegetation-MA, and Swamp alpine tundra vegetation-SA) on alpine tundra of Changbai Mountains, Jilin Province, China in growing seasons of 2003, 2004 and 2005. The biomass of 43 mono-species and soil nutrients in alpine tundra ecosystem were also investigated. Dominant species from Ericaceae (such as Rhododendron chrysanthum and Vaccinium jliginosum var. alpinum) were taken to analyze organ biomass distribution. Result showed that the biomass and elevation had a significant correlation (Biomass-237.3 in(Elevation) +494.36; R^2=0.8092; P〈0.05). No significant differences were found in phosphorus and sulphur concentrations of roots, stems and leaves among the five vegetation types. There were significant differences in nitrogen and phosphorus stocks of roots, stems and leaves and in sulphur stock of stems and leaves among TA, MA, and SA vegetation types (p〈0.05). The nutrient stock of five vegetations was averagely 72.46 kg.hm^-2, of which N, P, S were 48.55, 10.33 and 13.61 kg·hm^-2, respectively. Soil N and S concentrations in meadow alpine tundra soil type was significantly higher than those in other four soil types (Cold desert alpine tundra soil, Lithic alpine tundra soil, Peat alpine tundra soil, and Gray alpine tundra soil). Phosphorous concentration in SA type was higher (p〈0.05) than in other types. Soil nutrient stock (0-20cm) was averagely 39.59 t.hm^-2, of which N, P, S were 23.74, 5.86, 9.99 t·hm^-2, respectively.  相似文献   

17.
The effects of soil animals on soil nitrogen (N) mineralization and its availability were studied by investigating soil animal groups and their amounts of macro-faunas sorted by hand, and middle and microfaunas distinguished with Tullgren and Baermann methods under three Pinus sylvestris var. mongolica Litv. plantations in Zhanggutai sandy land, China. In addition, soil N mineralization rate was also measured with PVC closed-top tube in situ incubation method. The soil animals collected during growing season belonged to 13 orders, 5 groups, 4 phyla, whose average density was 86 249.17 individuals-m^-2. There were significant differences in soil animal species, densities, diversities and evenness among three plantations. Permanent grazing resulted in decrease of soil animal species and diversity. The average ammonification, nitrification and mineralization rates were 0.48 g:m^-2·a^-1, 3.68 g·m^-2·a^-1 and 4.16 g·m^-2·a^-1, respectively. The ammonification rate in near-mature forest was higher than that in middle-age forests, while the order of nitrification and net mineralization rates was: middle-age forest without grazing 〈 middle-age forest with grazing 〈 near-mature forest with grazing (P〈0.05). Soil N mineralization rate increased with soil animal amounts, but no significant relationship with diversity. The contribution of soil animals to N mineralization was different for different ecosystems due to influences of complex factors including grazing, soil characteristics, the quality and amount of litter on N mineralization.  相似文献   

18.
Two-year-old seedlings ofPinus koraiensis, Pinus sylvestriformis andFraxinus mandshurica were treated in open-top chambers with elevated CO2 concentrations (700 μL·L−1, 500 μL·L−1) and ambient CO2 concentrations (350 μL·L−1) in Changbai Mountain from June to Sept. in 1999 and 2001. The net photosynthetic rate, dark respiration rate, ribulose-1,5-bisphosphate carboxlase (RuBPcase) activity, and chlorophyll content were analyzed. The results indicated the RuBPcase activity of the three species seedlings increased at elevated CO2 concentrations. The elevated CO2 concentrations stimulated the net photosynthetic rates of three tree species exceptP. sylvestriformis grown under 500 μL·L−1 CO2 concentration. The dark respiration rates ofP. koraiensis andP. sylvestriformis increased under concentration of 700 μL·L−1 CO2, out that ofF. mandshurica decreased under both concentrations 700 μL·L−1 and 500 μL·L−1 CO2. The seedlings ofF. mandshurica decreased in chlorophyll contents at elevated CO2 concentrations. Foundation item: This paper was supported by the National Natural Science Foundation of China (No. 30070158). Knowledge Innovation Item of Chinese Academy of Sciences (KZCX2-406) and “Hundred Scientists” Project of Chinese Academy of Sciences. Biography: Zhou Yu-mei (1973-) Ph. Doctor, Assistant Research fellow Institute of Applied Ecology. Chinese Academy of Sciences. Shenyang 110016. P.R. China. Responsible editor: Song Funan  相似文献   

19.
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。  相似文献   

20.
The net CO2 assimilation rate, stomatal conductance, RuBPcase (ribulose 1,5-biphosphate carboxylose) activity, dry weight of aboveground and belowgroud part, plant height, the length and diameter of taproot ofPinus koraiensis seedlings were measured and analyzed after six-week exposure to elevated CO2 in an open-top chamber in Changbai Mountain of China from May to Oct. 1999. Seedlings were planted in four different conditions: on an open site, control chamber, 500 μL·L−1 and 700 μL·L−1 CO2 chambers. The results showed that the total biomass of the seedlings increased whereas stomatal conductance decreased. The physiological responses and growth to 500 μL·L−1 and 700 μL·L−1 CO2 varied greatly. The acclimation of photosynthesis was downward to 700 μL·L−1 CO2 but upward to 500 μL·L−1 CO2. The RuBPcase activity, chlorophyll and soluble sugar contents of the seedlings grown at 500 μL·L−1 CO2 were higher than that at 700 μL·L−1 CO2. The concentration 500 μL·L−1 CO2 enhanced the growth of aboveground part whereas 700 μL·L−1 CO2 allocated more carbon to belowground part. Elevated CO2 changed the carbon distribution pattern. The ecophysiological responses were significantly different between plants grown under 500 μL·L−1 CO2 and 700 μL·L−1 CO2. Foundation Item: This paper was supported by Chinese Academy of Sciences. Biography: HAN Shi-jie (1956-), male, Ph. Doctor, Professor in Laboratory of Ecological Process of Trace Substance in Terrestrial Ecosystem, Institute of Applied Ecology, Chinese Academy of Sciences. Responsible editor: Chai Ruihai  相似文献   

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