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1.
植物热值是森林生态系统中物质循环和能量转化评价的重要指标。利用假设检验和回归分析方法,对东北落叶松不同器官的热值和灰分含量进行了研究。结果表明:林木不同器官的热值和灰分含量在统计上大都存在显著差异,去灰分热值从大到小排序为叶(21.57 kJ/g)﹥枝(20.98 kJ/g)﹥皮(20.73 kJ/g)﹥根(19.88 kJ/g)﹥干(19.51 kJ/g),灰分含量排序为叶(5.79%)﹥皮(2.48%)﹥枝(1.88%)﹥根(0.95%)﹥干(0.47%);树干热值和灰分含量随树干从下往上呈增加趋势,且上、中、下部均存在显著差异;树根热值和灰分含量从根茎、粗根到细根也呈增加趋势,且两两之间差异显著;地上部分的平均干质量热值、去灰分热值和灰分含量均大于地下部分(树根),且差异显著;不同器官的热值和灰分含量与林木直径、树高和起源等因子显著相关,但其影响程度不尽相同。 相似文献
2.
南方马尾松不同器官的含碳系数分析 总被引：1，自引：0，他引：1
为了应对全球气候变化,森林碳储量监测日益受到重视,而含碳系数是一项重要的基础计量指标.以南方马尾松为对象,利用假设检验和回归分析方法,对不同器官的含碳系数进行系统分析.结果表明:马尾松不同器官的含碳系数存在显著差异,从大到小依次为树叶>干材>树根>树枝>干皮;树干不同高度干材和干皮的含碳系数也存在明显差异,但不同层次树... 相似文献
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《Forest Ecology and Management》1986,14(3):205-210
Equations predicting biomass of components of sawtimber-size trees in a near-maturity loblolly pine (Pinus taeda L.) plantation were compared to similar equations for an uneven-aged natural loblolly pine stand. Combined analysis of the two sites revealed that curves estimating total tree, stem wood, stem bark, branches, and foliage + branches weights were significantly different, while curves predicting biomass for total stem and foliage were similar. Biomass equations differ because of variations in tree component ratios and taper associated with site and stand conditions. 相似文献
5.
The fuelwood potential of indigenous (Acacia nilotica, Azadirachta indica, Casuarina equisetifolia, Dalbergia sissoo, Prosopis cineraria andZizyphus mauritiana) and exotics (Acacia auriculiformis, A. tortilis, Eucalyptus camaldulensis andE. tereticornis) trees were studied. Calorific value variations for components, such as, stump, main stem, treetop, branches, foliage and bark, were determined. Tree components differed highly significantly (P<0.01) among groups (indigenous and exotics) and within species. The calorific means ranged from 18.7 to 20.8 MJ/kg for indigenous tree species and 17.3 to 19.3 MJ/kg for exotics. Besides calorific values, other fuelwood characteristics, such as, density, ash, biomass/ash ratio, moisture and nitrogen content were also studied. It was observed that indigenous tree species are better suited as fuelwood species as they contain high density wood, low ash content and low N percentage. The fuelwood value index (FVI) was found to be high of indigenous tree species and was maximum forCasuarina equisetifolia (2815). The most promising tree species were in the order ofC. equisetifolia, A. nilotica andZ. mauritiana. 相似文献
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以中国南方马尾松为研究对象,对南方马尾松不同器官的碳素含量、灰分含量与去灰分热值的分布特征进行研究。结果表明：①南方马尾松林分的平均碳素含量、灰分含量与去灰分热值分别为50.55%,1.02%,21.74 kJ.g-1;枝、叶、干、皮、根相互之间的平均碳素含量、灰分含量、去灰分热值都具有显著性差异;②认为将树干（去皮）中部位（3.5/10树高处）碳素含量,皮的上、中、下部位的平均去灰分热值,枝的中、下部位的平均灰分含量可分别作为整株碳素含量、去灰分热值、灰分含量是可行的;③马尾松碳素含量、去灰分热值、灰分含量三者之间均存在较强的相关性,其中去灰分热值与灰分含量的相关性系数达0.668;④马尾松碳素含量比较稳定,与林木起源、胸径、年龄等因子相关不显著,而去灰分热值、灰分含量与胸径、年龄、冠幅、树高相关性显著,与起源、坡度、海拔等因子相关性不明显。 相似文献
7.
气候敏感的马尾松生物量相容性方程系统研建 总被引：1，自引：0，他引：1
【目的】构建气候敏感的马尾松生物量相容性方程系统,分析气候因子对马尾松各分项生物量的影响,为森林碳汇监测和森林可持续经营提供技术支撑。【方法】基于150株马尾松单木生物量数据,采用非线性联立方程组法构建气候敏感的马尾松生物量相容性方程系统,各分项生物量(干材、干皮、树枝、树叶和地上总生物量)选用以直径和树高为自变量的二元生物量方程作为基础模型,利用一阶交叉验证法对所构建的生物量相容性方程系统进行评价。【结果】与传统未考虑气候因子的各分项生物量模型相比,气候敏感的马尾松生物量相容性方程系统预测精度明显提高,且该生物量相容性方程系统可定量描述不同气候带亚区生物量的差异程度,保证干材、干皮、树枝和树叶与地上总生物量相容。【结论】气候敏感的马尾松生物量相容性方程系统能有效分析气候因子对各分项生物量的影响,可应用于其他树种的生物量预估。 相似文献
8.
Obtaining accurate and reliable information on biomass characteristics of tree species is important as it aids in selecting plant species that optimize fuel production for bioenergy. In this study, the net calorific value (NCV) and mineral concentration of 13 plant species selected from the Guinea savanna ecological zone of Ghana were investigated. Significant variation in NCV across the species components was found, with branch wood from most of the species exhibiting higher values compared to stem wood or the bark tissues. Accurate and reliable information on plant biomass could therefore be obtained through plant partitioning. High mobility of Zn and Pb after uptake was observed in the studied species. Apart from Cd whose concentrations in the species exceeded the recommended levels, no toxic levels were observed for the rest of the heavy metals. Thus, the major drawbacks in the use of the species as biomass resource are their higher concentrations of Cd and to some extent, higher ash contents. On account of the relatively high NCV, low ash content and low mineral concentrations, D. microcarpum, and C. febrifuga were found to be most suitable candidates for biomass production and subsequent bioenergy optimization in the Guinea savanna of Ghana. 相似文献
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本文以马尾松(Pinus massoniana)地上生物量数据为例,通过利用度量误差模型方法,研究建立了地上生物量与干、皮、枝、叶4个分量的相容性方程系统。首先,从各个分量所占比例变化特点分析入手,采用比值函数分级联合控制和比例函数总量直接控制2种方案构建了以地上总生物量为基础的相容性方程系统,其中对地上总生物量模型的估计,又采取了独立估计和联合估计2种处理方法。结果表明,分级联合控制方案和总量直接控制方案效果基本相当,而独立估计方法和联合估计方法也几乎没有差异。然后,还对一元、二元和三元模型的拟合效果进行了对比分析,结果显示随着解释变量的增加,估计值的标准误差和平均预估误差会有所下降,但对模型效果的改善幅度并不大。最后,对各个分量占地上总生物量的比例随直径的变化特点进行了分析,结果表明干材生物量所占比例随林木直径的增大而提高,干皮和树叶生物量所占比例则随林木直径的增大而下降,而树枝生物量所占比例相对比较稳定。本文所建立的相容性生物量方程系统,地上总生物量的预估精度达到95%以上,树叶生物量的预估精度最低,但也达到了85%以上。 相似文献
11.
5年生刺槐4个无性系的枝干生物量及热值对比分析 总被引：1，自引：0，他引：1
对河南省陕县5年生的3-I、豫刺槐1号、匈牙利四倍体、一般刺槐(CK)4个刺槐无性系的生物量、灰分含量、干质量热值和去灰分热值进行分析。结果表明:无性系间单位干质量热值和去灰分热值差异显著,分别在3750～3950kcal·kg-1与3800～4000kcal·kg-1之间,高低排序均为3-I>CK>豫刺槐1号>匈牙利四倍体;部位间单位干质量热值和去灰分热值差异显著,分别在3800～3960kcal·kg-1与3840～4000kcal·kg-1之间,高低排序均为树干中部>树枝>树干上部>树干下部;无性系间单株枝干干质量热值和去灰分热值差异显著,分别在10900～35000kcal与11000～35500kcal之间,无性系间单株枝干热值排序与枝干总生物量排序一致,均为豫刺槐1号>3-I>CK>匈牙利四倍体。综合热值、灰分含量和生物量分析,对刺槐进行能源林经营的品种选择是有效的,无性系豫刺槐1号选做能源刺槐树种栽培最为理想,3-I次之;树干中部为理想能量部位,树枝次之。 相似文献
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《Forest Ecology and Management》2002,159(3):241-248
Comparison of branch-level foliage and branch (wood+bark) biomass relationships for North Carolina Coastal (NCC) and Oklahoma/Arkansas (O/A) loblolly pine (Pinus taeda L.) seed sources provided an indication of biomass partitioning differences between these two seed sources. The objective of this study was to quantify and compare the branch-level foliage and branch biomass of NCC and O/A provenances on an excessively drained site in southeastern Oklahoma to assess their branch-level biomass partitioning patterns; a modeling process was developed to accomplish this objective. It was found that seed source significantly influenced the amount of foliage per branch. If tree and branch dimensions were held constant, NCC branches would carry approximately 30% more foliage per branch than O/A branches. The relationship between tree and branch dimensions and branch production did not differ for the two seed sources. Vertical distributions of branch and foliage biomass were found to be similar for the two seed sources as well. Thus, on the droughty site observed in this study: (1) the NCC seed source tended to partition more biomass into the foliage component at the individual branch level than did the O/A seed source; (2) the two seed sources were similar in their propensity to partition biomass into the branch component at the branch level, and (3) the two seed sources were similar in the vertical distribution of branch and foliage biomass within the crown. 相似文献
13.
Improving models of forest nutrient export with equations that predict the nutrient concentration of tree compartments 总被引：1，自引：0，他引：1
Laurent Augusto Céline Meredieu Didier Bert Pierre Trichet Annabel Porté Alexandre Bosc Frédéric Lagane Denis Loustau Sylvain Pellerin Frédéric Danjon Jacques Ranger Jacques Gelpe 《Annals of Forest Science》2008,65(8):808-808
14.
Valeria Reva Luís Fonseca José L. Lousada Isabel Abrantes Domingos X. Viegas 《European Journal of Forest Research》2012,131(4):1025-1033
The pinewood nematode (PWN), Bursaphelenchus xylophilus, the causal agent of the pine wilt disease, has been detected in several regions of Portugal affecting Pinus pinaster, a coniferous species of a great economic value. The nematodes, migrating through resin canals and feeding on parenchyma cells, induce rapid metabolic changes in ray parenchyma cells, cavitation areas, and denaturation and necrosis of parenchyma and cambial cells. To understand how anatomic changes and biochemical incidences of tree defense reactions affect the technological parameters of the wood, the gross calorific value (GCV) and chemical composition of PWN-infected and -uninfected P. pinaster wood were evaluated. The GCV was determined using Parr 6300 Automatic Isoperibol Calorimeter, and chemical composition analysis was performed by determining the contents of carbon, hydrogen, nitrogen, sulfur and Ash on complete and instant oxidation of samples by “flash” combustion. The Student’s t test with Welch correction was used for statistical data analysis. The difference between the GCV and chemical composition for PWN-infected and -uninfected P. pinaster wood was statistically significant for the GCV and for hydrogen and nitrogen contents. The carbon, oxygen, sulfur and Ash contents did not differ statistically. The GCV of PWN-infected wood varied between the highest value of hardwood and the lowest value of softwood. This interdisciplinary study stresses the important technological and economic aspects, namely the impact of PWN on wood properties and the suitability of infected P. pinaster wood for use in the wood-processing and energy industries. 相似文献
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Xuanran Li Qijing Liu Yongrui Chen Lile Hu Fengting Yang 《Frontiers of Forestry in China》2008,3(1):16-23
Regressive models of the aboveground biomass for three conifers in subtropical China—slash pine (Pinus elliottii), Masson pine (P. massoniana) and Chinese fir (Cunninghamia lanceolata)—were established. Regression analysis of leaf biomass and total biomass of each branch against branch diameter (d), branch length (L), d
3 and d
2
L was conducted with functions of linear, power and exponent. A power law equation with a single parameter (d) was proved to be better than the rest for Masson pine and Chinese fir, and a linear equation with parameter (d
3) is better for slash pine. The canopy biomass was derived by adopting the regression equations to all branches of each individual
tree. These kinds of equations were also used to fit the relationship between total tree biomass, branch biomass, foliage
biomass and tree diameter at breast height (D), tree height (H), D
3 and D
2
H, respectively. D
2
H was found to be the best parameter for estimating total biomass. However, for foliage biomass and branch biomass, both parameters
and equation forms showed some differences among species. Correlations were highly significant (P<0.001) for foliage biomass, branch biomass and total biomass, among which the equation of the total biomass was the highest.
With these equations, the aboveground biomass of Masson pine forest, slash pine forest and Chinese fir forest were estimated,
in addition to the allocation of aboveground biomass. The above-ground biomass of Masson pine forest, slash pine forest and
Chinese fir forest was 83.6, 72.1 and 59 t/hm2 respectively, and the stem biomass was more than the foliage biomass and the branch biomass. The underground biomass of these
three forests which estimated with others’ research were 10.44, 9.42 and 11.48 t/hm2, and the amount of carbon-fixed were 47.94, 45.14 and 37.52 t/hm2, respectively.
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Translated from Chinese Journal of Applied Ecology, 2006, 17(8): 1382–1388 [译自: 应用生态学报] 相似文献
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《Scandinavian Journal of Forest Research》2012,27(3):257-266
Abstract The interest in using stump biomass as a biofuel has recently increased in Sweden. The uneven consumption of wood fuel during the year creates a need for storage. This study examined the properties of stump biomass and how they vary at two sites in Sweden depending on harvesting technique, storage method and storage period. Norway spruce stumps, extracted using three different stump harvesting heads (Pallari, Rotary Cutter and Aalto), were stored in windrows or heaps. After 3 months, stumps stored in heaps were gathered into windrows. The fuel quality parameters moisture content (MC), ash content (AC) and calorific value (CV) were evaluated on five occasions in the period May 2008–September 2009. After 16 months of storage, the MC in all treatments had decreased to <25% (wet basis). Average AC decreased from 3.8% to around 1% (dry basis), whereas CV marginally increased. Stumps split during harvesting dried better than those harvested in one piece. The influence of storage method was minimal, although initial storage in heaps allowed better drying in the stumps harvested in one piece. In general, fuel quality improved in all treatments after storage. 相似文献
17.
湘乡市林地森林碳储量及碳密度研究 总被引：1，自引：0，他引：1
通过对湘乡市林地的森林碳储量、碳密度及碳储量的空间分布特征进行研究,得出:①在各优势树种组中,中生阔叶树组的碳储量和碳密度都是最大的,碳储量排序依次为:中生阔叶树组>马尾松组>杉木组>竹木组>国外松组>经济林组〉慢生阔叶树组>灌木组>速生阔叶树组,碳密度排序依次为:中生阔叶树组>国外松组>竹木组>马尾松组〉慢生阔叶树组>杉木组>经济林组>速生阔叶树组〉灌木组;②除马尾松组和中生阔叶树组外,各优势树种小班的碳储量主要集中分布在0~100t的区域内,且与人类活动呈负相关。 相似文献
18.
[Objective]To study the leaf calorific value of different forest types.[Method]This study focused on four common forest types widely distributed across China, including boreal coniferous forest, warm temperate deciduous broad-leaved forest, subtropical evergreen broad-leaved forest, and tropical monsoon forest. The leaf calorific values of 175 dominant (or common) tree species were measured. The leaf calorific value characteristics of the trees found in the different forest types were analyzed, and the primary factors affecting leaf calorific value were investigated, including leaf morphological traits, nutrient elements, climate, and soil traits. [Result]The results showed that in these forest types, the leaf calorific values ranged from 14.84 to 21.98 KJ·g-1, with an overall mean of 19.06 KJ·g-1. The presence of organisms appeared to affect the leaf calorific value, which differed among forest types as follows: coniferous trees > broadleaf trees or evergreen trees > deciduous trees. [Conclusion]The latitudinal pattern of tree leaf calorific value, ordered from north to south, is as follows: warm temperate deciduous broad-leaved forest > subtropical evergreen broad-leaved forest > tropical mountain rainforest. The mean leaf calorific value of boreal coniferous forest was slightly lower than those of warm temperate deciduous broad-leaved forest and subtropical evergreen broad-leaved forest. The leaf calorific values were significantly correlated with leaf carbon content (R2= 0.89, P<0.001). A multiple regression equation was established to describe the relationships among leaf calorific value, leaf carbon content, leaf nitrogen content, and leaf thickness. 相似文献
19.
We studied effects of tree age, size and competitive status on foliage and stem production of 43 Scots pine (Pinus sylvestris L.) trees in southern Finland. The tree attributes related to competition included foliage density, crown ratio and height/diameter ratio. Needle mass was considered to be the primary cause of growth through photosynthesis. Both stem growth and foliage growth were strongly correlated with foliage mass. Consequently, differences in growth allocation between needles and stem wood in trees of different age, size, or position were small. However, increasing relative height increased the sum of stem growth and foliage growth per unit foliage mass, indicating an effect of available light. Suppressed trees seemed to allocate more growth to stem wood than dominant trees, and their stem growth per unit foliage mass was larger. Similarly, trees in dense stands allocated more growth to stem wood than trees in sparse stands. The results conformed to the pipe model theory but seemed to contradict the priority principle of allocation. 相似文献
20.
《Scandinavian Journal of Forest Research》2012,27(7):594-604
Forest biomass estimation at large scale has become an important topic in the background of facing global climate change, and it is fundamental to develop individual tree biomass equations suitable for large-scale estimation. Based on the measured data of biomass components and stem volume from 100 sample trees of two larch species (Larix gmelinii and L. principis-rupprechtii) in northeastern and northern China, an integrated equation system including individual tree biomass equations, stem volume equation and height–diameter regression model were constructed using the dummy variable model and error-in-variable simultaneous equations. In the system, all the parameters of equations were estimated simultaneously, so that the aboveground biomass equation was compatible to stem volume equation and biomass conversion factor (BCF) function; the belowground biomass equation was compatible to root-to-shoot ratio (RSR) function; and stem wood, stem bark, branch and foliage biomass equations were additive to aboveground biomass equation. In addition, the system also ensured the compatibility between one- and two-variable models. The results showed that: (1) whether aboveground biomass equations or belowground biomass equations and stem volume equations, the estimates for larch in northeastern China were greater than those in northern China; (2) BCF of a larch tree decreased with the growing diameter while RSR increased with the growing diameter; (3) the proportion of stem wood biomass to aboveground biomass increased with the growing diameter while those of stem bark, branch, and foliage biomass decreased. 相似文献