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【目的】分析南亚热带常绿阔叶林4个常见树种的生物量器官分配特征,构建各树种单株及不同组分（地上部分和地下部分）生物量模型,以提高其生物量估算准确性。【方法】以位于广州市的南亚热带常绿阔叶林为对象,以该地区森林历史调查数据为依据,结合研究区实际树种组成,选取黧蒴、中华锥、千年桐和华润楠4个常见树种,采用收获法测定各树种不同组分生物量,构建各树种单株及各组分的生物量模型,并探讨树高（H）和木材密度（ρ）作为第二自变量以不同形式加入模型对模型精度的影响。【结果】4个树种树叶生物量占比为5.34%～7.28%,华润楠显著低于黧蒴（P<0.05）; 4个树种树枝生物量占比为16.82%～24.20%,华润楠显著低于中华锥和黧蒴（P<0.05）; 4个树种树干生物量占比为47.22%～58.05%,中华锥显著低于其他3个树种（P<0.05）; 4个树种树根生物量占比为14.25%～22.25%,黧蒴和千年桐显著低于中华锥和华润楠（P<0.05）;随着胸径增大,千年桐和华润楠的树叶生物量占比呈极显著下降趋势（P<0.01）,4个树种的树枝生物量占比均呈上升趋势,树干生物... 相似文献
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庆元林场阔叶林主要类型生物量测定及其评价 总被引：10，自引：0，他引：10
根据样地调查获得的数据,选择已建立的各种相关生物量预测模型进行统计,对千岗坑林区分别不同的阔叶林类型进行生物量的测定研究,结果表明,4个主要类型由于树种组成和林龄的不同,其直径分布变异较大,在生物量上阔杉混交林生物量最高达337.3t/hm2,常绿与落叶阔叶林的生物量最低为166.0t/hm2,在各类型的生物量组分中,树干组分的比例最大,其次为枝,再次是根,最低是叶。而生态功能的强弱序列为常绿阔叶林>常绿与落叶阔叶混交林>阔松混交林>阔杉混交林,木材生产能力的大小序列为阔杉混交林>阔松混交林>常绿阔叶林>常绿与落叶混交林。 相似文献
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对开化县常绿阔叶林、针叶林、常绿落叶阔叶混交林3种不同自然森林植被类型进行演替过程分析研究。结果表明,常绿阔叶林是该地森林植被自然演替的主要发展方向;常绿阔叶林、针叶林、常绿落叶阔叶混交林分别代表了森林植被不同演替类型与动态。结合森林群落类型和生境的异质性、群落树种组成与结构、演替阶段和演替趋势,根据森林植被景观的优美性、多样性等需求,对开化县主要通道两侧的森林植被确定了7类15种目标的森林植被景观改造方案,提出了森林景观优化"主景树种+地带性树种+伴生景观树种"的树种选择模式与营建技术。 相似文献
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长三角城市群园林绿化程度很高,但一些城市仍缺少乡土树种特色,危及生态系统稳定。长三角地跨北、中两个亚热带,有三类林木群落组成,即含有常绿阔叶树种的落叶阔叶林、落叶常绿阔叶混交林、常绿阔叶林。长三角范围乡土树种丰富,城市绿化以乡土树种为主,应大力推广应用。 相似文献
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《中南林业科技大学学报(自然科学版)》2017,(11)
缺乏阔叶树种生物量模型是影响亚热带常绿阔叶林生物碳库估测精度的重要原因,过去采用其他地区生物量模型估测亚热带常见阔叶林生物碳库,但其是否适用于本地区的阔叶林生物碳库估计仍存在争议。本研究在三明米槠林样地采用标准木结合相对生长方程法建立31株树的生物量模型,收集亚热带其他地区136株阔叶树生物量数据建立亚热带区域生物量模型,并与其他地区生物量模型比较。结果表明:亚热带区域阔叶林生物量模型为ln(AGB)=-1.982+1.209ln(D~2)和ln(AGB)=-2.907+0.932ln(D~2H),树高和胸径关系模型为ln(H)=0.469+1.082ln(d)-0.106ln(D)~2。Chave等建立的以胸径-树高为变量的湿润热带雨林生物量回归模型估算中亚热带森林生物量相对误差小于以胸径为变量建立的模型。Basuki、Brown、Chan、Ketterings和Kenzo等建立的生物量模型对我国中亚热带常绿阔叶林生物量估测精度不高,Ogawa的泰国常绿阔叶天然林生物量回归模型精度最高。该研究表明在利用区域生物量模型来估算中亚热带常绿阔叶林生物碳库应该检验其适用性,特别要考虑到模型的树种样本数量和胸径范围。 相似文献
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[目的]研究中亚热带地区的江西省内不同森林类型、林分类型林内倒木的生物量、碳储量及其数量特征分布格局,为该区域森林生态系统功能评估积累基础数据。[方法]以亚热带典型森林133个样地为研究对象,采用实测法对样方内直径≧1 cm,长度≧1 m的倒木逐一测量其中央直径和长度,并记录其分解程度和树种组成。[结果]表明:杉木林和马尾松林倒木生物量和碳储量分别为0.684 t·hm~(-2)、0.279 tc·hm~(-2)和0.553 t·hm~(-2)、0.207 tc·hm~(-2),常绿阔叶林和次生常绿阔叶林分别为11.293 t·hm~(-2)、4.781 tc·hm~(-2)和1.888 t·hm~(-2)、0.812 tc·hm~(-2),松阔混交林和杉阔混交林分别为1.248 t·hm~(-2)、0.521 tc·hm~(-2)和1.28 t·hm~(-2)、0.432 tc·hm~(-2);针叶林中Ⅱ、Ⅲ径级倒木生物量较大且与其他两个径级差异显著,针阔混交林中Ⅱ径级倒木与Ⅰ、Ⅲ径级倒木生物量差异显著,常绿阔叶林林内Ⅰ径级倒木生物量与Ⅱ、Ⅲ、Ⅳ和Ⅴ径级差异显著。杉木林和马尾松林中度分解倒木生物量最大分别为0.332 t·hm~(-2)、0.321 t·hm~(-2),且分别显著大于相应林分类型中的轻度和重度分解倒木;常绿阔叶林表现出同样的变化规律。[结论]中亚热带地区典型针叶林和常绿阔叶林中不同林分类型之间倒木生物量差异显著,而针阔混交林差异不显著。3种森林类型(针叶林、常绿阔叶林和针阔混交林)中不同林分类型之间倒木碳储量差异显著。江西森林倒木主要分布在5 10 cm和10 15 cm的Ⅱ、Ⅲ径级,且主要处于中度分解等级。针阔混交林(松阔和杉阔)倒木主要分布在海拔700 m以下,常绿阔叶林倒木分布在海拔650 m以上。研究结果表明,常绿阔叶林倒木由于其较大的生物量和碳储量可能会在缓解全球气候变暖和碳循环中扮演重要的作用,且在未来的森林经营和管理中应该重视倒木对森林可持续发展的重要性。 相似文献
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不同光环境下喜树与四川大头茶幼苗的表型可塑性 总被引：2，自引：1，他引：1
研究不同光环境对常绿阔叶林中喜树和四川大头茶幼苗生长的影响.结果表明:1)落叶阔叶树种喜树幼苗通过提高自遮荫程度、增大叶悬挂角、增加根生物量比和减小比叶面积适应旷地环境,在旷地中具有最大的相对生长速率,而常绿阔叶树种四川大头茶幼苗没有表现出对旷地光环境的良好适应;2)四川大头茶幼苗在林窗中通过增加叶片数、提高单叶面积、比叶面积和叶生物量比接受更多光能,相对于旷地和林下具有较快的高度生长,喜树幼苗比四川大头茶幼苗在林窗中具有更大的单叶面积、叶柄长度、总叶面积和总叶面积增长率;3)在3-8月,喜树在林窗中的株高增加约35.3 cm,约为四川大头茶(约6.6 cm)的5.3倍,喜树在林窗中具有明显的光资源竞争优势,表现出比常绿阔叶树种四川大头茶更高的相对生长速率,这就是喜树存在于常绿阔叶林的一个重要原因;4)郁闭林下的光资源有限,2个树种幼苗都不能在林下良好生长;5)喜树幼苗叶性状在不同光环境的可塑性指数远大于四川大头茶,这是喜树能够在常绿阔叶林中存在的另一重要原因. 相似文献
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星斗山自然保护区两种阔叶林的研究 总被引：1，自引：0，他引：1
星斗山自然保护区广泛分布着常绿阔叶林和常绿落叶阔叶混交林。他们生长繁茂,都是经过破坏后自然恢复起来的天然次生林。本文选择了钩栲林、水青冈、枫香、多脉青冈林为代表,研究了它们的种群结构状况,并探讨了其演替发展的前景。研究结果表明,这两种类型林分的种群结构都很复杂,组成林分的乔木树种分别为28种和29种,但前者常绿成分占88. 57%,后者常绿与落叶成分几乎各占一半。并且在海拔1000M 以下,以钩栲为主的常绿阔叶林是稳定的,而在1000～1500M 的范围里,只能形成常绿落叶阔叶混交林。 相似文献
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全国立木生物量建模总体划分与样本构成研究 总被引：8，自引：5，他引：3
结合全国生态地理区域和行政区域,并兼顾立木材积表的建模总体划分,提出了全国立木生物量建模总体划分方案,将全部树种分为34个树种组,全国分为6大地理区域,共划分70个建模总体;通过对已有立木生物量数据进行建模分析,将立木生物量模型的预估精度确定为95%以上,同时根据变动系数分析结果提出合适的建模样本单元数应该在150以上,且要按划定的10个径阶均匀分配,保证每个径阶的样本单元数不少于15个;以第七次全国森林资源清查数据为基础,确定了每一个建模总体的样本结构,将样本单元数全部落实到了各省和各级径阶。研究成果可为推进全国森林生物量调查建模工作提供参考依据。 相似文献
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《林业研究》2021,32(3)
Secondary Miombo woodlands and forest plantations occupy increasing areas in Mozambique, the former due to anthropogenic activities. Plantations, mainly species of Eucalyptus and Pinus, are being established on sites previously covered by secondary Miombo woodlands. This affects the evolution, cycle and spatiotemporal patterns of carbon(C) storage and stocks in forest ecosystems. The estimation of C storage, which is indispensable for formulating climate change policies on sequestrating CO_2, requires tools such as biomass models and biomass conversion and expansion factors(BCEF). In Mozambique, these tools are needed for both indigenous forests and plantations. The objective of this study is to fit species-specific allometric biomass models and BCEF for exotic and indigenous tree species. To incorporate efficient inter-species variability, biomass equations were fitted using nonlinear mixed-effects models. All tree component biomass models had good predictability; however, better predictive accuracy and ability was observed for the 2-predictors biomass model with tree height as a second predictor. The majority of the variability in BCEF was explained by the variation in tree species. Miombo species had larger crown biomass per unit of stem diameter and stored larger amounts of biomass per stem volume. However, due to relatively rapid growth, larger stem diameters, heights, and stand density, the plantations stored more biomass per tree and per unit area. 相似文献
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SA Hamzath Kora Cédric A Goussanou Achille E Assogbadjo Brice Sinsin 《Southern Forests》2019,81(2):111-122
Allometric equations are required for a rapid estimation of commercial timber volume and forest biomass stocks. In order to preserve the forest ecosystem, this study applied a non-destructive sampling approach to measure biophysical properties of living trees. From these measurements, volume and biomass models were developed for 11 dominant tree species in a semi-deciduous natural forest and for Acacia auriculiformis in a plantation located in southern Benin. The observations were combined to develop also generic models applicable to non-dominant tree species. Wood samples of the tree species were collected with an increment borer and analysed in the laboratory to determine species-specific wood densities. The sample size was composed of 243 trees in natural forest and 21 trees in plantation. The measurements were conducted in 30 plots of 50 m × 50 m. The graphical assessment of correlation between model outputs (biomass and volume) and variables (diameter and height) and the statistical analysis confirmed that the logarithmic model with two variables had the best predictions. The assessment also confirmed that the model using diameter only as a variable had good predictions when observations on height were unavailable. The comparative analysis of model predictions showed that the generic model in this study over-estimated biomass by up to 74.80% for certain species and under-estimated biomass by 21.18% for other species. The study shows that there are no statistically significant differences between the wood densities in this research and that published in previous studies. 相似文献
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依据中国西南地区栎类和桦木的立木材积及生物量实测数据,采用度量误差模型的方法,建立栎类和桦木材积相容的地上生物量及地下生物量模型。结果表明,在地上生物量模型中,增加树高因子,立木材积模型的相关统计指标有较大幅度的改进,栎类和桦木二元材积模型的平均预估精度分别达到了97.86%和97.08%,而二元地上生物量模型的相关统计指标并没明显的改进;两树种一元与二元地下生物量模型的相关统计指标差异并不明显,平均预估精度均达到了90%以上。 相似文献
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《Southern Forests》2013,75(2):77-88
Estimating tree volume and biomass constitutes an essential part of the forest resources assessment and the evaluation of the climate change mitigation potential of forests through biomass accumulation and carbon sequestration. This research article provides stem volume and biomass equations applicable to five tree species, namely Afzelia africana Sm. (Caesalpiniaceae), Anogeissus leiocarpa (DC.) Guill. and Perr. (Combretaceae), Ceiba pentandra (L.) Gaertn. (Bombacaceae), Dialium guineense Willd. (Caesalpiniaceae), Diospyros mespiliformis Hochst. ex A.DC. (Ebenaceae) in natural protected tropical forests and, in addition, Tectona grandis L.f. (Verbenaceae) in plantations. In addition to the tree species specific equations, basic wood density, as well as carbon, nitrogen, organic matter and ash content were determined for these tree species in tropical conditions in West Africa. One hundred and sixty-two sample trees were measured through non-destructive sampling and analysed for volume and biomass. Stem biomass and stem volume were modelled as a function of diameter (at breast height; Dbh) and stem height (height to the crown base). Logarithmic models are presented that utilise Dbh and height data to predict tree component biomass and stem volumes. Alternative models are given that afford prediction based on Dbh data alone, assuming height data to be unavailable. Models that include height are preferred, having better predictive capabilities. Ranges in carbon, nitrogen and ash contents are given as well. The successful development of predictive models through the use of non-destructive methods in this study provide valuable data and tools for use in determining the contribution of these major African rainforest tree species to global carbon stocks, while ensuring the preservation of this valued African resource. This study needs to be expanded to further regions and tree species to complete a full inventory of all tree species, emphasising the relevance of African trees to carbon stocks at a global scale. 相似文献
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吕勇 《中南林业科技大学学报(自然科学版)》1996,(2)
通过研究马尾松林分生物量与林分蓄积量、林分平均胸径、平均高、林分密度的相关关系，揭示了马尾松林分生物量的密度效应，提出了马尾松水保林的最适经营密度． 相似文献
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Quantitative information of tree biomass is useful for management planning and monitoring of the changes in carbon stock in both forest and agroforestry systems. An estimate of carbon stored in these systems can be useful for developing climate change mitigation strategies. A precise estimate of forest biomass is also important for other issues ranging from industrial forestry practices to scientific purposes. The individual tree-based biomass models serve as fundamental tools for precise estimates of carbon stock of species of interest in forest and agroforestry systems. We developed individual tree aboveground biomass models for Castanopsis indica using thirty-six destructively sampled tree data covering a wide range of tree size, site quality, growth stage, stand density, and topographic characteristics. We used diameter at breast height (DBH) as a main predictor and height-to-DBH ratio (a measure of tree slenderness) and wood density (a measure of stiffness and cohesiveness of wood fibres) as covariate predictors in modelling. We, hereafter, termed the biomass models with former two predictors as first category models (density independent models) and the models with all three predictors as second category models (density dependent models). Among various functions evaluated, a simple power function of the form \(y_{i} = b_{1} x_{i}^{{b_{2} }}\), in each category, showed the best fits to our data. This formulation, in each category, described most of the biomass variations (\(R_{adj}^{2}\) > 0.98 and RMSE < 72.2) with no significant trend in the residuals. Since both density dependent and density independent models exhibit almost similar fit statistics and graphical features, one of them can be applied for desired accuracy, depending on the access of the input information required by the model. Our biomass models are site-specific, and their applications should therefore be limited to the growth stage, stand density, site quality, stand condition, and species distribution similar to those that formed the basis of this study. Further research is recommended to validate and verify our model using a larger dataset with a wider range of values for site quality, climatic and topographic characteristics, stand density, growth stage, and species distribution across Nepal. 相似文献
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【目的】无人机机载激光雷达能够准确地测定单木、林分乃至大尺度森林结构参数(树高和树冠因子)。为应用无人机激光雷达技术准确估测森林蓄积量、生物量和碳储量提供计量依据和技术支撑。【方法】以150株实测马尾松生物量样本数据为研究对象,采用非线性回归估计方法和度量误差联立方程组方法,分析立木材积和地上生物量与树高、树冠因子的相关性,并在此基础上研究建立基于树高和树冠因子的立木材积与地上生物量相容模型。【结果】单株材积和地上生物量与树高因子的相关性最为紧密,其次才是树冠因子;基于树高和冠幅因子的二元材积和地上生物量模型预估精度较高,达到92%以上,再考虑冠长因子的三元模型预估精度改进不大;基于树高和冠幅因子的二元立木材积与地上生物量相容模型估计效果更好,相对于一元相容模型系统而言,二元相容模型拟合效果有较大幅度提高,预估精度达到92%以上。【结论】采用度量误差联立方程组方法可以有效解决基于树高和树冠因子的立木材积与地上生物量相容问题,并且预估精度达到92%以上,所建二元立木材积与地上生物量相容模型可为应用激光雷达技术反演森林蓄积量和生物量提供计量依据。 相似文献
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We analyzed the relationship between species richness and biomass in natural forest communities at two similar sites on Mt. Xiaolongshan, northwest China. At both sites, a wide range of tree layer biomass levels was available by local biomass estimation models. In order to identify underlying mechanism of the species richness-biomass relationship, we included different water resource levels and number of individuals in each plot in our analysis. We sampled 15 and 20 plots （20 m ×20 m）, respectively, at both two sites. These plots were sampled equally on the sunny slope and the shady slope. Species richness, number of individuals of each species and diameter at breast height （DBH） as a substitute of biomass of tree layer were recorded in each sample. At one site, the relationship between species richness and biomass was significant on the sunny slope, and this relationship disappeared on the shady slope due to more environmental factors. The relations between species richness and number of individuals and between number of individuals and biomass paralleled the species richness-biomass relation on both slopes. The difference in number of individuals-biomass relationships on the sunny slope and the shady slope revealed ＂interspecific competitive exclusion＂ even though the species richness-biomass relationships were not hump-shaped. At the other site, species richness was not related to biomass or to number of individuals. Our study demonstrated the importance of environmental stress and succession of community in the understanding of species diversity-productivity patterns. 相似文献