林木分化对兴安落叶松异速生长方程和生物量分配的影响

林木因对资源竞争而产生分化,从而影响林木的异速生长方程和生物量分配,但其影响程度还不清楚。采用林木相对直径法将38株兴安落叶松(Larix gmelinii)样木在林分中的分化等级分为优势木、中等木和被压木,量化林木分化对林木异速生长方程和生物量分配的影响。结果显示:生物量组分异速生长方程多以胸径(DBH)为自变量为好,但以枝下高处的树干直径为自变量估测其枝、叶生物量时更精确。在一定的胸径范围内,同一胸径下不同林木分化等级的地下部分各组分生物量没有显著差异(P0.05),但优势木分配更多的生物量给枝和叶,中等木比优势木分配更多的生物量给树干,中等木比被压木分配更多的生物量给地上部分,而且被压木和中等木的树高显著高于优势木。除根茎生物量之外,不同林木分化等级的生物量组分(包括枝、叶、树干和根系)的相对分配比例无显著差异(P0.05),根冠比保持相对稳定。这些结果表明,主要由竞争而引起的林木分化改变了兴安落叶松地上生物量组分的异速生长和分配,但其相对分配格局较为保守。     

长白落叶松、日本落叶松和兴安落叶松幼苗光合作用特性比较研究

研究长白落叶松(Larix olgensis Herry.),日本落叶松(Larix kaempferi Carr.) 和兴安落叶松(Larix gmelinii Rupr.)当年生和一年生幼苗的光合作用日变化、季节变化和光响应曲线,结果表明：①三种植物中,长白落叶松、日本落叶松当年生和一年生幼苗和兴安落叶松当年生幼苗光合速率日变化都呈双峰曲线,具有明显的“午休”特征。兴安落叶松一年生幼苗的光合速率日变化呈单峰曲线。②日本落叶松的光饱和点 (LSP) 最高,兴安落叶松光补偿点（LCP）最低。③三种落叶松的一年生幼苗都是在生长中期表现出最大的光合能力。从年龄来看,落叶松当年生幼苗在生长初期和生长中期的光合能力要低于一年生幼苗,但在生长后期高于一年生幼苗。④从种来看,生长初期,当年生和一年生幼苗的最大净光合速率(P_max)均为日本落叶松＞兴安落叶松＞长白落叶松;生长中期,当年生幼苗的P_max规律与生长初期相似,一年生幼苗的P_max为长白落叶松＞日本落叶松＞兴安落叶松;生长后期,当年生幼苗的P_max为长白落叶松＞兴安落叶松＞日本落叶松,一年生幼苗的P_max与生长中期一年生幼苗的规律正好相反。通过分析我们得到结论：三个树种在生长季节相同阶段具有不同的光合特性;每个种不同年龄和生长季节不同阶段也表现出不同的光合特性;三个树种中,长白落叶松幼苗对光抑制引起的光合器官损伤的修复能力最强,日本落叶松次之,兴安落叶松最弱;日本落叶松幼苗较喜光,光合作用能力较强,不易发生光抑制,而兴安落叶松幼苗较耐阴。因此在育苗和造林时应考虑不同树种的光合特性调节最佳的光照条件。     

中国东北落叶松属植物rbcL 基因的序列分析及系统演化

长白落叶松的分类位置及与兴安落叶松的种间关系, 长期以来未有定论。本研究从大兴安岭、小兴安岭及张广才岭等6 个地点采集实验材料, 对其叶绿体DNA 的rbcL 基因进行PCR-RFLP 分析并测序。结果显示它们的rbcL 基因序列均没有差异, 表明东北地区落叶松属植物有共同起源。在系统演化上, 长白落叶松来自兴安落叶松(Larix gmelinii Rupr.), 应作为兴安落叶松的变种即L.gmelinii Rupr.var.olgensis Ostenfeld et S.Larsen     

中国东北落叶松属3种植物潜在分布对气候变化的敏感性分析

该文在东北地区多年平均的年均温、年降水分布图,海拔高程图、坡度图、坡向图和植被图的基础上,使用地理信息系统和Logistic回归模型的结合,预测3种落叶松(Larix sp.)的“气候-地形”潜在分布区。预测精度用敏感性、指定度和总正确率进行评价,3个树种的敏感性为61%~88%,指定度为80%~99.8%,总正确率为80%~99.8%。年均温、年降水和海拔是控制3种落叶松分布的主要环境因子。采用5种气温变化方案(+1 ℃、+2 ℃、+3 ℃、+4 ℃和+5 ℃)和6种降水变化方案(-30%、-20%、-10%、+10%、+20%和+30%),预测气候变化对各个树种潜在分布的影响,探索不同的树种对气候因子的敏感性。结果表明,气温每上升1 ℃,兴安落叶松(Larix gmelinii)将减少12%;长白落叶松(Larix olgensis var. changpaiensis)将增加23%;华北落叶松(Larix principis-rupprecntii)将增加500%。降水每增加10%,兴安落叶松将减少12.5%;长白落叶松将增加64%;华北落叶松将减少15%;随气候的“暖干化"(+5 ℃,-30%),兴安落叶松将向西北方退缩100 km左右;长白落叶松向西北方扩展100 km左右;华北落叶松将向东北方扩展800 km左右。随气候的“暖湿化"(+5 ℃,+30%),兴安落叶松将向西北退缩400 km左右;长白落叶松将向西北方扩展550 km;华北落叶松将向东北方扩展320 km左右。     

大兴安岭不同生态区域兴安落叶松树高曲线的研究

以大兴安岭3个不同生态区域的兴安落叶松伐倒木为对象,基于2 272株实测树高—胸径数据,分别选用12种树高曲线模型,对模型参数进行求解,并采用确定系数（R²）、误差(Bias)、均方根误差（RMSE）对模型精度进行检验。结果表明,Korf方程,唐守正方程和Hossfeld方程能较好地描述区域1和区域3的落叶松树高曲线;Richard方程,Weibull方程和Mitscherlich方程能较好地描述区域2的落叶松树高曲线。采用限制模型和无限制模型的假设检验方法对所选模型进行区域性检验。结果表明,任何2个区域的树高曲线都有显著不同,且区域2与区域1和区域3的树高曲线相差较大,区域1和区域3的树高曲线相差较小。不同生态区域树高曲线的错误应用会导致较大的预测误差。     

兴安、长白及华北落叶松RAPD 分子标记的物种特异性鉴定

以中国北方地区主要乡土落叶松树种兴安落叶松(Larix gmelini)、长白落叶松(L. olgensis)和华北落叶松(L. principisrupprechtii)的针叶及种子胚乳为研究材料, 采用RAPD分子标记技术对3种落叶松进行不同物种的种间鉴别。结果表明, 通过引物筛选得到了4个可以鉴别3种落叶松的RAPD引物, 其中有2个引物在落叶松针叶和种子胚乳基因组中都扩增出相同的条带。引物OPB-11在兴安和长白落叶松基因组DNA中1 500 bp处扩增出特异条带, 而在华北落叶松中没有; 引物OPX-14在兴安落叶松基因组DNA中1 200 bp处扩增出特异条带, 而在长白落叶松中没有; 还有2个引物可分别作为3种落叶松苗木和种子鉴别的辅助标记。本研究从分子水平上为落叶松的种间鉴别提供了新的鉴定方法。     

兴安、长白及华北落叶松RAPD分子标记的物种特异性鉴定

以中国北方地区主要乡土落叶松树种兴安落叶松（Larix gmelini）、长白落叶松（L.olgensis）和华北落叶松（L．principis—rupprechtii）的针叶及种子胚乳为研究材料,采用RAPD分子标记技术对3种落叶松进行不同物种的种间鉴别。结果表明,通过引物筛选得到了4个可以鉴别3种落叶松的RAPD引物,其中有2个引物在落叶松针叶和种子胚乳基因组中都扩增出相同的条带。引物OPB-11在兴安和长白落叶松基因组DNA中1500bp处扩增出特异条带,而在华北落叶松中没有：引物OPX-14在兴安落叶松基因组DNA中1200bp处扩增出特异条带,而在长白落叶松中没有：还有2个引物可分别作为3种落叶松苗木和种子鉴别的辅助标记。本研究从分子水平上为落叶松的种间鉴别提供了新的鉴定方法。     

3种落叶松幼苗对CO2升高的光合生理响应

采用Li-6400便携式光合作用测定系统研究CO2升高对长白落叶松(Larix olgensisHerry.),日本落叶松(Larix kaempferiCarr.)和兴安落叶松(LarixgmeliniRupr.)当年生和1年生幼苗的光合特性的影响。结果表明:CO2升高使3种落叶松光饱和光合速率(Pmax)和呼吸速率均有不同程度的增加,其中,长白落叶松当年生和1年生幼苗Pmax分别比对照提高了91%和83%,日本落叶松当年生和1年生幼苗Pmax分别比对照提高了71%和94%,而兴安落叶松当年生和1年生幼苗Pmax分别比对照提高了32%和106%。除兴安落叶松外,CO2升高使所有落叶松当年生幼苗的光补偿点(LCP)下降,说明当年生幼苗对CO2浓度升高的反应更敏感。CO2升高使日本落叶松当年生和1年生幼苗光饱和点(LSP)都升高,反映了其光合作用提高的潜力较大。CO2升高条件下,除1年生兴安落叶松外,其他处理的落叶松最大量子效率(AQYmax)均增加。比较分析表明,在未来大气CO2浓度升高条件下,日本落叶松的生长潜能可能最大,具有较强的生态优势,长白落叶松次之,兴安落叶松最小。     

亚热带常绿阔叶林9个常见树种的生物量相对生长模型

生物量相对生长模型作为一种简便且有效的生物量估算方法,已得到广泛应用.国内偏重于针叶林或阔叶纯林的生物量相对生长模型研究,而在估算多树种阔叶林的生物量时,一般选用混合物种的生物量相对生长模型,这会导致估算结果产生较大误差.本文在亚热带常绿阔叶林典型分布区随机设置了33块样地,针对栲树、鹿角锥、钩锥、石栎、猴欢喜、虎皮楠、赤杨叶、乳源木莲和少叶黄杞9个常见的树种,构建了单物种及混合物种的生物量相对生长模型,并探讨了单物种模型及混合物种模型间估算误差的差异.结果表明:以D(胸径)和D2H(胸径的平方乘以树高)为自变量,分别构建混合物种模型,其中树枝、树叶、树根、地上和整株生物量是以D为自变量的模型为优,但树干生物量是以D2H为自变量的模型为优.将树高引入以D为自变量的单物种模型后,6个树种单物种模型的解释能力呈不同程度的下降趋势,最高下降5.6%(猴欢喜).与以D和D2H为自变量的混合物种模型相比,8个树种单物种模型的SEE(估计值的标准差)出现下降;对不同器官而言,其单物种模型的SEE不同程度地下降,最高达13.0%和20.3%(树枝).不考虑种间和模型形式间的差异,将会严重影响生物量碳库及其动态评估的准确性.因此,为提高生物量估算的准确性,应综合考虑种间和模型形式间的差异.     

千烟洲人工林主要树种地上生物量的估算

利用不同参数和函数,模拟了千烟洲人工林主要树种马尾松、湿地松和杉木的枝条、叶生物量和总生物量及单株各器官生物量,选择最佳函数计算生物量在各树种不同器官中的分配,估算不同林型的地上生物量.结果表明,不同树种的枝条基径(d)和枝条生物量(BW)、叶生物量(LW)之间,当d³为自变量时,相关系数最高,湿地松利用线性函数、马尾松和杉木利用幂函数模拟效果最佳;单木总生物量以利用D²H(胸径²×树高)为自变量的幂函数模拟相关系数最高;3个树种叶和枝生物量各有不同的最佳自变量和函数类型,但同一树种的叶、枝生物量最佳拟合方程的自变量和函数类型一致.马尾松林、湿地松林和杉木林的地上生物量分别为83.6、72.1和59 t·hm^-2,其中树干生物量所占比重最大,叶生物量最小.根据前人的研究结果推算3种林分地下生物量分别为10.44、9.42和11.48 t·hm^-2,其固碳量分别为47.94、45.14和37.52 t·hm^-2.     

大兴安岭不同演替阶段天然林物种多度格局模拟

为实现大兴安岭地区落叶松天然林的全周期可持续经营,以新林林业局翠岗林场3块100m×100m不同演替阶段(白桦林、落叶松-白桦混交林和落叶松林)的天然林固定调查样地数据为基础,采用统计模型(对数正态模型)、生态位模型(断棍模型、生态位优先占领模型、Zipf模型、Zipf-Mandelbrot模型)和中性模型(群落零和多项式模型、Volkov模型)对不同演替阶段天然林的乔木层、幼苗层和由乔木层划分的不同林层的物种多度格局进行拟合,并用χ² 检验和Kolmogorov-Smirnov检验选择最佳模型。结果表明:(1) 在大兴安岭地区不同演替阶段的落叶松天然林群落中,Zipf-Mandelbrot模型的拟合效果均最好。(2) 对数正态模型对于稳定的演替阶段白桦林和落叶松林的群落相较于过渡阶段群落落叶松-白桦混交林的物种多度分布的拟合效果更好。(3) 在大兴安岭地区落叶松天然林中,生境过滤主导群落构建,随着群落不断演替生境过滤和中性过程减弱。(4) 天然林群落乔木层的群落构建过程与乔木层内不同生长阶段林层的构建过程不同,生境过滤过程在落叶松林乔木层中逐渐减弱,而在落叶松林不同生长阶段的林层和更新层中增强。     

Characteristic Isozyme Spectra of Anionic Peroxidases and Superoxide Dismutases in Callus Cultures of Larix sibirica Ledeb. and Larix gmelinii Rupr. Rupr.

Multiple molecular forms of anionic peroxidase (AP) and superoxide dismutase (SOD) were investigated in the callus lines of Larix sibirica and L. gmelinii. Eight distinct patterns of the AP spectra were discerned among 13 investigated lines. The spectra of SOD molecular forms were similar in all lines under investigation, although the lines were obtained from two Larix species and the calli were of different origin. Fe-containing SOD was for the first time described in the Larix isoenzyme spectrum. The authors conclude that the SOD isozyme spectra in dedifferentiated cells of L. sibirica and L. gmelinii are more stable than the isoperoxidase spectra.     

基于树木起源、立地分级和龄组的单木生物量模型

以马尾松(Pinus massoniana)和落叶松(Larix)的大样本实测资料为建模样本,以独立抽取的样本为验证样本,把样本按起源、立地和龄组进行分级,采用与材积相容的两种相对生长方程,分普通最小二乘和两种加权最小二乘,对地上部分总生物量、地上各部分生物量和地下生物量进行模型拟合和验证,使用决定系数、均方根误差、总相对误差和估计精度等8项统计量对结果进行分析。结果表明:两个树种地上部分总生物量,立地分类方法,模型的拟合结果和适用性都最优;马尾松VAR模型较优,而落叶松CAR模型较好;两种加权最小二乘方法,在建模样本和验证样本中表现得不一致。在建模样本中,加权回归2(权重函数1/f^0.5)略优于加权回归1(权重函数1/y^0.5),但在验证样本中,加权回归1却明显优于加权回归2。而同时满足建模样本拟合结果最优和验证样本检验结果最优的组合中,只有加权回归1。两个树种地上部分各分量生物量,模型拟合结果和适用性,均为干材最优,树叶最差、树枝和树皮居中,样本分类、模型类型和加权最小二乘方法对干材生物量的影响,规律和地上部分总生物量相同;样本分类、模型类型和加权最小二乘方法的最优组合,用验证样本检验的结果,总相对误差树枝不超过±10.0%,树皮不超过±5.0%,树叶马尾松不超过±30.0%,落叶松不超过±20.0%。两个树种地下部分(根)生物量,样本按龄组分类方法,模型拟合结果最优,与材积相容的模型总体上优于与地上部分总生物量相容模型。     

Assessing the above‐ground biomass of a complex tropical rainforest using a canopy crane

Abstract Current estimates of the total biomass in tropical rainforests vary considerably; this is due in large part to the different approaches that are used to calculate biomass. In this study we have used a canopy crane to measure the tree architectures in a 1 ha plot of complex mesophyll vine forest at Cape Tribulation, Australia. Methods were developed to measure and calculate the crown and stem biomass of six major species of tree and palm (Alstonia scholaris (Apocynaceae), Cleistanthus myrianthus (Euphorbiaceae), Endiandra microneura (Lauraceae), Myristica insipida (Myristicaceae), Acmena graveolens (Myrtaceae), Normanbya normanbyi (Arecaceae)) using the unique access provided by the crane. This has allowed the first non‐destructive biomass estimate to be carried out for a forest of this type. Allometric equations which relate tree biomass to the measured variable ‘diameter at breast height’ were developed for the six species, and a general equation was also developed for trees on the plot. The general equation was similar in form to equations developed for tropical rainforests in Brazil and New Guinea. The species equations were applied at the level of families, the generalized equation was applied to the remaining species which allowed the biomass of a total of 680 trees to be calculated. This has provided a current estimate of 270 t ha⁻¹ above‐ground biomass at the Australian Canopy Crane site; a value comparable to lowland rainforests in Panama and French Guiana. Using the same tree database seven alternative allometric equations (literature equations for tropical rainforests) were used to calculate the site biomass, the range was large (252–446 t ha⁻¹) with only three equations providing estimates within 34 t ha⁻¹ (12.5%) of the site value. Our use of multiple species‐specific allometric equations has provided a site estimate only slightly larger (1%) than that obtained using allometric equations developed specifically for tropical wet rainforests. We have demonstrated that it is possible to non‐destructively measure the biomass in a complex forest using an on‐site canopy crane. In conjunction the development of crown maps and a detailed tree architecture database allows changes in forest structure to be followed quantitatively.     

利用混合模型分析地域对国内马尾松生物量的影响

开展全国森林生物量监测和评估,建立适合较大区域范围的通用性立木生物量模型是一项重要的基础工作,而分析森林生物量受不同地域的影响并保证不同尺度范围森林生物量估计值的可靠性,是必须面临的问题。以南方马尾松(Pinus massoniana)地上生物量数据为例,介绍了如何利用混合模型理论来分析地域对马尾松地上生物量的影响以及利用混合模型构建全国通用性立木生物量模型,为得到不同区域尺度范围内可靠的森林生物量评价和估计提供了有效途径。结果表明,混合模型不仅提高了模型的精度和通用性,并且模型中每个参数都有特定的数学含义,通过这些参数很容易分析出随机因子对生物量的影响程度。因此混合模型方法具有较大的灵活性和适应性,可推广到其它通用性模型(如材积方程)的建立。     

不同林分起源的相容性生物量模型构建

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。     

Comparisons of recruitment, survival, and growth in invasive and native saplings on a volcano

We monitored the recruitment, survival, and growth of tree saplings on invasive (Larix kaempferi) versus native species (Betula and Populus) using 16 20 m × 20 m plots established along elevation gradient on the volcano Mount Koma, Japan, for 7 years because the sapling behaviors should determine forest structures. The crowding of overstory consists mostly of Larix decreased with increasing elevation. Larix recruits were conspicuous, particularly at middle elevation where overstory crowding was intermediate, while Betula recruits were least. Larix overstory crowding inhibited the recruitment of all the taxa, although intermediate crowding promoted the recruitment of Larix. The restriction of sapling emergence was conspicuous at lower elevation where the overstory crowding was highest, probably because of shading, and/or competition with overstory trees. Sapling recruitment for all taxa was restricted at higher elevation, due to high stresses derived from direct solar radiation and strong wind without overstory. The survival of saplings was 96% for Larix and Betula, while it was ca. 50% for Populus. Larix overstory decreased the survival and growth of all the taxa, except Larix survival and Betula growth. The results implied that Larix could establish by high survival once the recruits succeeded everywhere and native sapling regeneration was restricted by Larix overstory. Strong recruitment, survival, and growth of Larix, together with resistance to overstory crowding, enables it to dominate and persist in such disturbed areas regardless of the canopy closure.     

Fine root architecture, morphology, and biomass of different branch orders of two Chinese temperate tree species

We have limited understanding of architecture and morphology of fine root systems in large woody trees. This study investigated architecture, morphology, and biomass of different fine root branch orders of two temperate tree species from Northeastern China—Larix gmelinii Rupr and Fraxinus mandshurica Rupr —by sampling up to five fine root branch orders three times during the 2003 growing season from two soil depths (i.e., 0–10 and.10–20 cm). Branching ratio (R _b) differed with the level of branching: R _b values from the fifth to the second order of branching were approximately three in both species, but markedly higher for the first two orders of branching, reaching a value of 10.4 for L. gmelinii and 18.6 for F. mandshurica. Fine root diameter, length, SRL and root length density not only had systematic changes with root order, but also varied significantly with season and soil depth. Total biomass per order did not change systematically with branch order. Compared to the second, third and/or fourth order, the first order roots exhibited higher biomass throughout the growing season and soil depths, a pattern related to consistently higher R _b values for the first two orders of branching than the other levels of branching. Moreover, the differences in architecture and morphology across order, season, and soil depth between the two species were consistent with the morphological disparity between gymnosperms and angiosperms reported previously. The results of this study suggest that root architecture and morphology, especially those of the first order roots, should be important for understanding the complexity and multi-functionality of tree fine roots with respect to root nutrient and water uptake, and fine root dynamics in forest ecosystems.     

Soil warming and CO2 enrichment induce biomass shifts in alpine tree line vegetation

Responses of alpine tree line ecosystems to increasing atmospheric CO₂ concentrations and global warming are poorly understood. We used an experiment at the Swiss tree line to investigate changes in vegetation biomass after 9 years of free air CO₂ enrichment (+200 ppm; 2001–2009) and 6 years of soil warming (+4 °C; 2007–2012). The study contained two key tree line species, Larix decidua and Pinus uncinata, both approximately 40 years old, growing in heath vegetation dominated by dwarf shrubs. In 2012, we harvested and measured biomass of all trees (including root systems), above‐ground understorey vegetation and fine roots. Overall, soil warming had clearer effects on plant biomass than CO₂ enrichment, and there were no interactive effects between treatments. Total plant biomass increased in warmed plots containing Pinus but not in those with Larix. This response was driven by changes in tree mass (+50%), which contributed an average of 84% (5.7 kg m^?2) of total plant mass. Pinus coarse root mass was especially enhanced by warming (+100%), yielding an increased root mass fraction. Elevated CO₂ led to an increased relative growth rate of Larix stem basal area but no change in the final biomass of either tree species. Total understorey above‐ground mass was not altered by soil warming or elevated CO₂. However, Vaccinium myrtillus mass increased with both treatments, graminoid mass declined with warming, and forb and nonvascular plant (moss and lichen) mass decreased with both treatments. Fine roots showed a substantial reduction under soil warming (?40% for all roots <2 mm in diameter at 0–20 cm soil depth) but no change with CO₂ enrichment. Our findings suggest that enhanced overall productivity and shifts in biomass allocation will occur at the tree line, particularly with global warming. However, individual species and functional groups will respond differently to these environmental changes, with consequences for ecosystem structure and functioning.