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1.
紫果云杉天然中龄林分生物量和生产力的研究   总被引:10,自引:0,他引:10       下载免费PDF全文
江洪 《植物生态学报》1986,10(2):146-152
本文对四川松潘地区海拔3200—3300m的紫果云杉(Picea purpurea)天然中龄林分生物量和生产力进行了测定和研究。按平均标准木法和样方收获法分别调查了乔木层、幼树下木层、草本地被物层和枯枝落叶层的生物量。据调查数据,建立了估测乔木层单株林木各器官生物量的回归方程,方程的相关系数和估测的精度都较高,具有实用价值。结果表明:林分总生物量平均为158.779吨/公顷,净生产量为3.259吨/公顷·年。其中乔木层生物量为134.408吨/ 公顷,净生产量为2.890吨/公顷·年。研究证实叶面积指数与林分乔木层的生产力关系十分紧密。在—定范围内,叶面积指数为4.34的林分比叶面积指数3.32的,其乔木层净生产量可增加47.2%。林冠浓密的林分比林冠稀疏的生产力要高。另外,林分的产量结构上反映出下层木结 构不合理,应予间伐。  相似文献   

2.
森林生物量是林业生产经营和森林资源监测的重要指标,为探索高效低偏的单木生物量估测方法,引入人工神经网络.本研究采用黑龙江省东折棱河林场的101株长白落叶松地上生物量数据,基于不同变量(胸径、树高、冠幅)组合建立了4个聚合模型体系(AMS),采用加权回归消除模型的异方差.然后,基于最优的变量组合建立人工神经网络(ANN)...  相似文献   

3.
不同林分起源的相容性生物量模型构建   总被引:4,自引:0,他引:4  
目前为止已有不同方法构建生物量相容性模型,但不同林分起源的生物量相容性模型很少报道。针对此问题,以150株南方马尾松(Pinus masson iana)地上生物量数据为例,利用比例平差法和非线性联立方程组法建立不同起源地上生物量以及干材、干皮、树枝和树叶各分项生物量相容的通用性模型。根据分配层次不同,两种方法又各自考虑总量直接控制和分级联合控制两种方案。从直径、树高、地径、枝下高和冠幅5个林分变量中选取不同的变量构建一元、二元和三元生物量模型,并利用加权最小二乘回归法消除生物量模型中存在的异方差性。结果为:比例平差法和非线性联立方程组法都能有效保证各分项生物量总和等于总生物量,模型预测精度满足要求。总体而言,非线性联立方程组方法比比例平差方法精度高,同时两种方法中总量直接控制法比分级联合控制法预测效果好;各分项生物量模型本身作为权函数能有效消除异方差;各分项对应的三元生物量模型预测精度最高,其次是二元生物量模型,最低是一元生物量模型,但这些差异不是很大。总之,为权衡考虑模型预测精度和调查成本,建议把直径和树高作为协变量利用总量直接控制非线性联立方程组法对不同起源生物量建模。  相似文献   

4.
小陇山油松林乔木层生物量相容性线性模型   总被引:3,自引:0,他引:3  
以甘肃小陇山的油松林分为对象,应用图形分析、相关分析和回归分析法,建立了基于森林资源调查资料的林分生物量相容性线性模型.结果表明,小陇山油松林分各组分生物量(W)与林分活立木蓄积量(V)、与林分平均胸径-平均树高-林分密度(-D2-Hρ)均存在极其显著的线性相关关系.采用代数和法,建立了W=a bV、W=a b(-D2-Hρ)2种形式的林分乔木层生物量相容性线性模型,以95%的可靠性估计,2种形式模型的预估精度均在95%以上.理论上证明了W=a 6V这种建立在林分水平上的生物量线性估计模型可直接推广应用到区域尺度.  相似文献   

5.
杉木人工林生物量估算模型的选择   总被引:7,自引:0,他引:7  
采用11种形式的生物量模型,分别对杉木幼龄林(7年生)、中龄林(16年生)、成熟林(28年生)和不分林龄的单木各器官和全株生物量进行拟合,共得到生物量估算模型308个.结果表明: 11种生物量模型均能较好地模拟杉木单木生物量,其中幂函数模型的拟合效果最优,其次为指数模型,然后为多项式模型;共选出估算杉木幼龄林、中龄林和成熟林各器官和全株生物量的最优模型21个(包括18个器官模型、3个全株模型),不分林龄的杉木单木各生物量的最优模型7个(包括6个器官模型、1个全株模型),均为幂函数模型;不同林龄的杉木单木生物量最优模型的通用性较差,而不分龄林的杉木单木生物量最优模型具有一定的通用性,精度较高,可用于估算不同林龄的杉木单木生物量.应用福建邵武杉木单木生物量模型对江西28年生的杉木成熟林单木各生物量的预测结果显示,不分林龄的大样本生物量模型精度较高,可在较大范围内应用,而区域小样本模型仅限于在区域小范围内应用.  相似文献   

6.
森林生物量估算中模型不确定性分析   总被引:2,自引:1,他引:2  
秦立厚  张茂震  钟世红  于晓辉 《生态学报》2017,37(23):7912-7919
单木生物量估算是区域森林生物量估算的基础。量化单木生物量模型中各种不确定性来源,分析各不确定性来源对森林生物量估算的影响,可为提高森林生物量估算精度提供理论依据。基于52株杉木地上部分生物量实测数据,建立杉木单木地上部分生物量一元与二元模型。在两种模型形式下,根据临安市2009年森林资源连续清查数据中杉木实测数据,分析单木生物量模型中所包含的2种不确定性,即模型参数不确定性和模型残差变异引起的不确定性。最后利用误差传播定律计算单木生物量模型总不确定性。结果表明,基于一元生物量模型的临安市杉木生物量估计均值为6.94 Mg/hm~2,由一元模型残差变异引起的生物量不确定性约为11.1%,模型参数误差引起的生物量不确定性约为14.4%,一元生物量模型估算合成不确定性为18.18%。基于二元生物量模型的临安市杉木生物量估计均值为7.71 Mg/hm~2,模型残差变异引起的不确定性约为7.0%,模型参数误差引起的不确定性约为8.53%,二元生物量模型估算合成不确定性为11.03%。研究表明模型参数不确定性随建模样本的增加逐渐降低,当建模样本由30增加到40再增加到52时,一元生物量模型模型参数不确定性分别为20.26%、16.19%、14.4%,二元生物量模型分别为13.09%、9.4%、8.53%。此外,建模样本的增加对残差变异不确定性也有一定影响,当建模样本由30增加到42再增加到48时,一元模型残差变异不确定性分别为15.2%,12.3%和11.7%;二元模型残差变异不确定性分别为13.3%,9.4%和8.3%。在2种不确定性来源中模型参数不确定性对估计结果影响最大,其次为模型残差变异。由于模型残差变异、参数不确定性与建模样本有关,因此可以通过增加建模样本来减小模型参数不确定性。二元生物量模型总的不确定性要低于一元生物量模型。  相似文献   

7.
目的:建立新疆云杉蓄积及地上生物量模型,为在林分尺度上估算云杉碳储量及生产力提供基础数据。方法:利用收获法采集西伯利亚云杉(Picea obovata)与雪岭云杉(Picea schrenkiana)各50株,以蓄积为自变量,地上生物量为因变量,采用4种生物量模型进行回归分析构建模型,综合模型评价、参数估计值的稳定性及相对误差筛选出最优生物量模型。结果:确定W=0.515V0.926 (R2=0.980)为西伯利亚云杉估测模型,W=0.541V0.953 (R2=0.954)为雪岭云杉估测模型。结论:新疆云杉蓄积和地上生物量极显著相关,4种估测模型以幂函数拟合效果最优。  相似文献   

8.
湿地翅碱蓬生物量遥感估算模型   总被引:5,自引:4,他引:5  
傅新  刘高焕  黄翀  刘庆生 《生态学报》2012,32(17):5355-5362
以黄河三角洲HJ-1A CCD遥感数据和滨海湿地翅碱蓬生物量实测数据为数据源,通过对比分析参数回归模型(单变量线性和非线性回归模型,多元线性逐步回归模型)和人工神经网络模型(BP网络、RBF网络、GRNN网络),构建黄河三角洲湿地翅碱蓬生长初期的生物量湿重遥感估算最优模型。研究表明:基于遥感信息变量能够建立生长初期翅碱蓬生物量湿重估算模型。尽管基于RDVI、MSAVI和PC2的3个变量的多元线性回归模型的拟合效果较优,但是以SAVI、MSAVI、RVI、DVI、RDVI和PC2等7个遥感信息变量构建的BP神经网络模型的精度更高,平均相对误差为12.73%,估算效果最优,能够满足较高精度的生物量湿重估算需求。翅碱蓬生长初期生物量湿重最优估算模型的建立,为滨海地区植被生物量监测、区域翅碱蓬生物量季节动态模拟以及黄河三角洲生态系统功能评价提供技术支持与基础。  相似文献   

9.
黄土高原北部典型灌丛枝条生物量估算模型   总被引:3,自引:0,他引:3  
杨宪龙  魏孝荣  邵明安 《生态学杂志》2016,27(10):3164-3172
于2015年8月末在陕西神木县六道沟小流域采集200个柠条和210个沙柳枝条,测定枝条的基径(D)、长度(H)、含水量(W0)、鲜质量(WF)和干质量(W),选用指数函数和异速生长方程建立了4种由枝条形态指标估算枝条生物量的简易模型,并对模型的拟合效果进行验证. 结果表明: 对于柠条和沙柳灌丛,基于DH二者组合变量(D2H)的异速生长方程是估算枝条生物量的最优模型,该模型经线性转化后可以消除生物量数据的异方差性,且拟合效果最优,决定系数(R2)最大,平均误差(ME)、平均绝对误差(MAE)、总相对误差(TRE)、平均系统误差(MSE)和平均绝对百分误差(MPSE)整体上最小,基本满足生态学研究的精度要求.  相似文献   

10.
11.
植物温度是森林生态系统能量平衡和植被呼吸估算的重要参数.采用T型热电偶监测树皮和木材特性各异的2个阔叶树种(白桦和水曲柳)不同深度、高度和方位的树干温度(Ts),探索Ts日变化的空间变异及其影响因素.结果表明: Ts月平均日变化格局与空气温度呈相似的正弦曲线,但Ts变化滞后于空气温度,时滞从树皮表面处的0 h增加到6 cm深度处的4 h.随测定深度的增加和高度的降低,Ts日变化的峰值和日较差均逐渐减小.Ts周向差异不大,休眠季节白天南向、西向Ts日峰值略高.两树种树皮和木材的热学特性(比热容和导热系数)的差异,会通过影响树干表面与外界的热交换和树干内部热扩散而造成Ts径向变化的种间差异.白桦树皮较高的反射率削弱了太阳辐射对Ts的影响.多元逐步回归分析表明,环境因子可以很好地估测Ts日动态(R2>0.85),影响程度依次为空气温度>水汽压>净辐射>风速.估算生物量热储和树干表面CO2通量时应考虑Ts径向、纵向和种间差异.  相似文献   

12.
基于森林调查数据的长白山天然林森林生物量相容性模型   总被引:9,自引:1,他引:9  
森林生物量估算是进行陆地生态系统碳循环和碳动态分析的基础,但现有估测模型存在着总量与分量不相容的问题.本文以吉林省汪清天然林区为例,提出了基于森林调查的相容性森林生物量模型设计思想,并采用联立方程组为不同森林群落构造了一系列引入林分蓄积因子的相容性生物量模型,得到的预估精度较高.其中,针叶林、阔叶林和针阔混交林群落的森林生物量模型预估精度均在95%以上,基本上解决了森林生物量模型的相容性问题.  相似文献   

13.
不同施水量对云杉幼苗生长和生理生态特征的影响   总被引:14,自引:0,他引:14  
杨燕  刘庆  林波  吴彦  何海 《生态学报》2005,25(9):2152-2158
在中国科学院成都生物研究所茂县生态站,参照云杉分布区的年降水量,设置4种水分处理梯度(分别模拟年降水量为350mm、700mm、1000mm和1350mm),研究云杉幼苗的生长和生理特征差异。经过4a的研究,结果表明,不同施水量显著影响了云杉幼苗的株高、基径、生物量积累(叶重、茎重和根重)、主根长度、第一级侧根数量、气体交换、叶绿素含量、脯氨酸以及丙二醛含量。700mm施水量的云杉幼苗的以上参数显著高于其他3个施水量(350mm、1000mm和1350mm)的幼苗。干旱胁迫下,云杉幼苗净光合速率和蒸腾速率显著降低,抑制了云杉幼苗生物量积累;过量施水则降低了云杉幼苗的根生长。云杉幼苗通过调节水分利用效率来适应不同的水分条件,当受到干旱胁迫时,通过提高水分利用效率来提供生长所需要的水分;然而当水分充足的时候,水分利用效率又降低。此外,水分不足和过量均导致针叶叶绿素含量降低,同时引起丙二醛含量的增加,表明云杉幼苗不适宜在土壤过于干旱和湿润的条件下生长。  相似文献   

14.

Key message

Growth conditions related to inter-tree competition greatly influence black and white spruce foliage biomass and projected leaf area characteristics.

Abstract

Foliage characteristics such as biomass and area are important among other reasons because they can be related to tree growth. Despite their economic and ecologic importance, equations to characterize foliage biomass and projected area of black (Picea mariana (Miller) BSP) and white (Picea glauca (Moench) Voss) spruces are sparse. Total foliage biomass and projected leaf area, foliage biomass and leaf area density, and relative vertical distribution of black and white spruces foliage biomass and leaf area were modelled with linear and nonlinear mixed effect models. A total of 65 white spruces and 57 black spruces were destructively sampled at four different locations in Alberta, Québec, and Ontario, Canada. Our results show that for each species, total tree foliage biomass and projected leaf area is proportional to stem diameter, total height, and crown length. The addition of crown length in the equations improved the precision of the predictions of total foliage biomass for both species and diminishes greatly the site level random effect. An increase in DBH for black spruce and in the DBH to total height ratio for white spruce skewed the relative vertical foliage biomass distribution toward the base of the living crown. According to our results, growth conditions or tree development stage influence both foliage biomass and leaf area characteristics of black and white spruces. Our results emphasize the importance of inter-tree competition on foliage biomass characteristics.  相似文献   

15.
This study tests the hypotheses that (1) the above-ground structure of Norway spruce (Picea abies [L] Karst.) is derivable from the functional balance theory, and that (2) crown ratio is a key source of structural variation in trees of different age and social position. Twenty-nine trees were measured in three stands (young, middle-aged, and mature), with three thinning treatments (unthinned, normal, and intensive) in the two older stands. There was a strong linear relationship between the total cross-sectional area of branches and that of stem at crown base. Foliage mass was linearly related with stem basal area at crown base. Also an allometric relationship was found between foliage mass and crown length. The mean length (weighted by basal area) of branches obeyed an exponential function of crown length. The parameters of most of these relationships were independent of slenderness (tree height/breast height diameter) and tree age However, total branch cross-sectional area per stem cross-sectional area in the young trees was greater than in the older trees. The young trees also had slightly shorter branches than predicted by the mean branch length equation. This was probably caused by branch senescence which had not yet started in the young stand. The older trees had a relatively long lower crown segment which was growing slowly and senescing. It was proposed that a segmented crown structure is characteristic of shade tolerant tree species, and that the structural model could be further developed by making the two segments explicit.  相似文献   

16.
亚高山针叶林人工恢复过程中生物量和材积动态研究   总被引:7,自引:2,他引:7  
研究了近70年不同林龄亚高山人工云杉林的地上部分生物量及材积变化规律.结果表明,20年林龄前的云杉单株生物量增长缓慢,以小枝和叶生长为主,约占50%;20年以后,单株生物量增长加快,以树干积累为主,大体上超过60%;30年后增长速度相对减慢,自40年开始并保持快速增长.云杉种群生物量表现出类似的增长,但林龄在30至50年间增长速度减慢.群落生物量总体上持续增长,但灌木层生物量在初期快速增长,从20年林龄后逐渐减少;草本层生物量则一直减少,到70年时仅占不足0.2%.在近70年人工恢复过程中,云杉单株材积平均生长量和连年生长量都逐渐增大,越在后期生长越迅速;林分蓄积则在30至50年林龄之间有一段连年生长量相对减小的时期.根据树干解析资料,建立了70年人工云杉林的单株材积与胸径和树高的数学模型.  相似文献   

17.
Summary We investigated abscisic acid (ABA) metabolism among Norway and white spruce somatic embryo cultures which exhibited differences in maturation response when placed on racemic abscisic acid [(±)-ABA]. Differences in metabolic rate among the spruce genotypes could affect the ABA pool available for the maturation process, and might therefore be responsible for the differences in maturation response. The production of cotyledonary (stage 3) somatic embryos in cultures (genotypes) of Norway spruce (PA86:26A and PA88:25B) and of white spruce (WS1F cryoD and WS46) was compared. In each species pair one of the two genotypes failed to show stage 3 embryo development (respectively, PA88:25B and WS46). The investigation of ABA metabolism of each species pair showed that no substantial differences in ABA consumption or in the production of metabolites occurred. In each case ABA was metabolized to phaseic acid and dihydrophaseic acid over the 42-day culture period, metabolites were recoverable from the agar-solidified medium, and the sum of residual ABA and metabolites were equivalent to the ABA initially supplied. The results indicate that the process of ABA metabolism occurs essentially independently of somatic embryo maturation. NRCC no. 37345.  相似文献   

18.
The genetic diversity of ten natural populations of Picea asperata Mast. were studied using RAPD markers. A total of 160 reproducible fragments were produced from the ten primers used. The mean number of fragments detected per individual was 114.7. Altogether 120 fragments were polymorphic among the ten populations, none of them were found to be population-specific. Nei's expected heterozygosity (H (e)) ranged from 0.233 to 0.269, and the average was 0.247. The analysis of molecular variance revealed that the coefficient of gene differentiation among populations, based on F (ST) and the unbiased estimate PhiST, equaled 0.224 and 0.290, respectively. Such high values indicate that there is significant differentiation among populations, which could result from several factors, including restricted gene flow between populations (Nm = 0.866). Founder events may be another factor attributing to the high level of genetic differentiation. In addition, it was discovered that the geographic distribution is not correlated with the genetic distances among the populations of P. asperata.  相似文献   

19.
Interior spruce (Picea glauca engelmannii complex) and black spruce (Picea mariana Mill.) cotyledonary somatic embryos were encapsulated in sodium alginate. Somatic embryo viability was retained, but germination occurred at a reduced frequency compared with the equivalent zygotic embryos. The addition of 0.5% (w/v) activated charcoal to the alginate capsule significantly enhanced root development and germination for somatic embryos but not for zygotic embryos. The possibility of developing an artiflcal endosperm was also investigated, by addition of Litvay (Litvay et al. 1981) nutrients with or without 90 mM sucrose to the alginate-charcoal capsule. This treatment significantly enhanced root development for all embryo categories with the exception of black spruce somatic embryos. Encapsulated and non-encapsulated somatic embryos survived one month cold storage at 4 °C without reduction in germination frequency.NRCC No. 35895  相似文献   

20.
One of the main seed storage proteins of Norway spruce ( Picea abies ), is a salt-soluble protein with an average molecular mass of 42 kDa. This protein was localized by immunocytochemical methods in ultrathin sections of megagametophytes active in storage protein synthesis, as analyzed by SDS-PAGE. The megagametophyte in spruce starts accumulating storage materials, proteins and lipids, as the young embryo grows into the gametophytic tissue. It then continues to accumulate these storage products throughout seed development (Hakman 1993). Megagametophytes at an early stage of storage protein accumulation were chosen in this study for analysing the likely transport pathway of the proteins, since only a small amount of lipid had yet accumulated in the cells, and cell organelles were still easy to distinguish. An antibody against the 42 kDa storage protein showed very good reactivity with the 42 kDa protein in immunoblot experiments with total protein extracts from megagametophytes and embryos. In ultrathin sections of the megagametophyte, the antibodies were preferentially localized in the lumen of Golgi cisterna, in Golgi-associated vesicles, protein deposits close to the vacuolar membrane and in protein storage vacuoles (protein bodies). These observations indicate that the transport is mediated by the Golgi apparatus.
Also, proteins present in storage vacuoles in mature zygotic and somatic embryos showed intense labelling with these antibodies in ultrathin sections.  相似文献   

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