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1.
采用典型抽样方法,对长白山北坡不同海拔高度带云冷杉林的植物种类组成进行了初步研究。结果表明,组成长白山北坡各类云冷杉林的种子植物和蕨类植物共计109种,分属43科88属,其中乔木植物15种,灌木层植物21种,草本植物73种。  相似文献   

2.
长白山自然保护区位于长白山北坡。从植被的分布,可把长白山北坡的林型划分为:杜鹃岳桦林、红松云冷杉暗针叶林、杜香落叶松林、灌木阔叶红松林和胡枝子长白赤松林五个主要林型。长白山北坡土壤也有明显的垂直带分布。从山顶到山麓,土壤的垂直分布可划分为:山地苔原土、山地生草森林土、山地棕色针叶林土和山地暗棕色森林土四个主要土壤类型。我们在1982年,对山地棕色针叶林土上生长的杜香落叶松林、山地暗棕色森林土上生长的胡枝子长白赤松林和灌木阔叶红松林。三个主要林型下土壤微生物生态分布的季节性动态变化?进行了调查和分析。  相似文献   

3.
通过对土壤温度的定位观测(土壤深度5cm处)及分析,长白山北坡3种不同林型土壤氮矿化速率表现为季节动态变化,与土壤温度季节动态变化比较相似。在不同月份氮矿化速率存在较大差异。在7、8月份时,氮矿化速率最大且红松云冷杉林土壤氮矿化速率明显高于阔叶红松林和岳桦云冷杉林。而在11、12、1~3月份之间氮矿化速率比较低且变化比较平稳。主要是因为温度对氮矿化速率起限制作用。就不同林型而言,阔叶红松林土壤年氮矿化量是44.13kg/hm2.a为最高,其次是红松云冷杉林31.3kg/hm2.a和岳桦云冷杉林25.73kg/hm2.a。因此阔叶红松林土壤供氮潜力更大。  相似文献   

4.
基于28个20mx90m样地的调查数据,利用Lotka-Volterra模型,本文分析了长白山北坡阔叶红松(Pinuskoraiensis)林和云冷杉林(也叫暗针叶林)群落交错区优势树种之间的竞争及动态。结果显示:在自然条件下,群落将向两个方向分化,一是以云杉(PiceajezoensisandP.koraiensis)和冷杉(Abiesnephrolepis)为优势的群落,并在达到平衡时冷杉占绝对优势(相对优势度的77.1%):另一种是以红松或云冷杉和阔叶树占绝对优势的针阔混交林,并在达到平衡时,阔叶树在阔叶红松林中占相对优势度的50%,在云冷杉一阔叶林类型中占66%。同时,本研究说明:(1)阔叶红松林和云冷杉林都是长白山气候顶极群落:(2)交错区具有过渡性质:(3)森林群落的分化结果说明演替的方向受局部生境的影响。图1表3参24。  相似文献   

5.
[目的]长白山自然保护区以原始林为主,森林结构复杂,稳定性好。建立自然保护区60年来,仅在2019年大规模暴发了落叶松毛虫灾害。本研究旨在对致灾状况和致灾因子进行分析。[方法]以长白山自然保护区遭受虫害的北坡森林为研究对象,设置样地,在2019年和2020年进行了监测,对森林受损和恢复情况进行了研究;并从气象条件和森林结构两个方面探究了长白山地区落叶松毛虫大暴发的原因。[结果]研究表明:(1)长白山自然保护区整体上成灾区发生比例不大,但局部受灾程度很重。虫灾区占到长白山自然保护区北坡总面积的12.5%,其中,一般灾区占21.8%,重灾区占79.2%。受灾的主要树种为鱼鳞云杉、臭冷杉、红松和长白落叶松。(2)长白山落叶松毛虫成灾区森林有所恢复,但是不同林型恢复程度差异明显。长白落叶松林受损林全部恢复,红松阔叶林中红松纯林以及海拔1 100 m至1 300 m云冷杉林重度受损林恢复差。(3)3种受损林型林分结构存在差异,导致3种林型虫口的密度存在差异。云冷杉针叶林竞争指数和大小比数低,树势强,虽然其多样性和混交度高,但都是针叶树种,可视为纯林,因此受害最重。红松针阔混交林竞争指数和大小比数...  相似文献   

6.
为了评价现有云冷杉林的质量,给合理经营提供依据。本文在延边州范围内搜集省级样地80块,长白山自然保护区样地10块,县局级样地375块。分析了云冷杉林的树种组成结构、林分密度、各径阶间的株数变化和林分生长过程等情况,并据此提出了合理经营现有云冷杉林的意见。  相似文献   

7.
以长白山过伐林区金沟岭林场的云冷杉林4个局级固定样地连续12年的观测数据为研究对象,利用固定样地内主要针叶树种红松、冷杉和云杉,从1978年到1984年6年内的胸径与定期平均生长量对应值数据,建立林木径阶生长转移概率模型,预估林木径阶平均生长量,并利用1990年观测数据进行检验,结果表明:所建概率模型实际应用误差较小,精度较高;同时还分析了1978年至1990年12年间云冷杉林的枯损林木株数分布特征,通过模型模拟和检验,表明Weibull分布函数适用于异龄混交林的枯损株数分布模拟。  相似文献   

8.
《林业科学》2021,57(5)
【目的】研究长白山北坡云冷杉阔叶混交过伐林乔木层物种多度格局,阐明过伐林群落冠层结构维持的生态过程,探讨生境异质性、密度依赖、种间关联、扩散限制、更新限制和物种分化在针阔混交林群落装配中的作用,为揭示过伐林恢复过程中的物种多度分布机制提供理论指导。【方法】采用经验统计模型、生态位模型、群落中性理论模型以及复合生态位模型,对长白山北坡12块云冷杉阔叶混交过伐林样地进行物种多度格局分析。【结果】经验统计模型中对数正态模型和泊松对数正态模型拟合效果最佳,对数级数模型拟合效果较差,对数级数模型参数T和对数正态模型参数λ可作为表征群落多样性的重要参数;生态位模型中断棍模型拟合效果最佳,其次是生态位重叠模型和几何级数模型,再次为Zipf模型和Zipf-Mandelbrot模型,最后为随机分配模型和优势优先模型;复合生态位模型拟合效果较传统生态位模型有较大提高,复合模型可能在群落丰富种和稀有种呈现竞争等级多度分布时拟合效果最佳;以胸高断面积为指标的物种多度分布拟合与以个体数为指标的经验统计模型和生态位模型物种多度分布拟合表现基本一致,而在群落中性理论模型和复合模型拟合表现方面有一定差异,可能与稀有种断面积比重较大有关。【结论】复合模型可能成为连接经验模型、生态位模型和中性理论模型的纽带,为研究物种多度格局提供数学途径和思路。云冷杉阔叶混交过伐林群落物种等级多度分布某种程度上是生态位过程和随机干扰生态过程共同作用的结果。  相似文献   

9.
长白山云冷杉针阔混交过伐林优化结构研究   总被引:4,自引:0,他引:4  
以中国东北部长白山过伐天然林为研究对象,通过20多年的连续监测,使用4~14次的复测数据,探索不同经营方式下天然林的生长动态,从森林蓄积量、林分密度、树种组成、径级结构及q值、大中小径级比例等方面,研究天然林的优化结构及其目标,并得出与优化结构相匹配的经营措施,这对现实长白山云冷杉林的经营有普遍的实践意义。  相似文献   

10.
我局云冷、杉占优势的林分,面积均占过熟林的38%。主重类型有阔叶云、冷杉林、枫桦云、冷杉林、红松云、冷杉林及云、冷杉林。在海拔1400米处,分布有岳桦、鱼鳞松林。对云、冷杉林分。我局历来采取择伐作业。1961年以前实行径级择伐,以后是采育择伐。据1979年采伐更新普查,全局择伐比重占80.3%,而云,冷杉林分则几乎百分之百实行择伐。为了观察择伐后林分生长及更新效果,从1974年起,按不同地理位置,不同立地类型  相似文献   

11.
Disease and insect surveys of three Southern Appalachian spruce-fir ecosystems were conducted between 1985–1988. Visual tree decline was correlated with the presence of fungal pathogens and insect pests. Fungi were isolated from tree cankers, necrotic roots and diseased foliage; while insect incidence and impact was assessed visually. With the exception of damage to Fraser fir inflicted by the balsam wooly adelgid, little significant pathology or insect infestation was noted. This survey indicates that major diseases and insect damage, particularly on red spruce, appear not be primarily causal in the observed forest decline.  相似文献   

12.
Fraser fir (Abies fraseri [Pursh] Poir.) and red spruce (Picea rubens Sarg.) are codominants of southern Appalachian spruce-fir forests. Fraser fir generally dominates above 1740 m, while red spruce usually dominates below this elevation. This study was designed to determine whether the present segregation of the two species along elevational gradients is associated with seedling competition or contrasting physiological responses to environmental factors. Seedlings were grown for two years in a replacement series experiment along two elevational transects extending from 1300 m to 1900 m, and harvested for growth analysis.Competition increased with decreasing elevation and Fraser fir was apparently the stronger competitor. Mortality was inversely correlated with elevation and was most evident in red spruce in May, and in fir in late summer. Fir growth increased with elevation and red spruce grew most at the middle elevation (1600 m). Neither competitive interactions nor growth responses completely explained the elevational segregation of red spruce and Fraser fir. We hypothesize that the early-successional Fraser fir quickly dominates at higher elevations following disturbance and that continued disturbance will favor its dominance at higher elevations. However, the late-successional noncompetitive red spruce slowly establishes itself and, while consistently present, may only dominate in the absence of disturbance and where other species are at the margins of their distribution.  相似文献   

13.
The maximum size–density relationships or self-thinning lines were developed for three mixed-softwood climax forest habitats (hemlock-red spruce, spruce-fir, and cedar-black spruce) in the northeastern USA. The plot data were collected from an extensive data base used in growth studies from 1950 to 1970, and represented a wide range of species compositions, sites, management options, and densities. Plots having late successional species compositions with relative density index higher than 0.7 were selected as the most fully-stocked plots for model development. Reduced major axis regression was used to fit the self-thinning lines to the data. The differences between the three forest habitats were tested using the 95% confidence intervals of the coefficients of the self-thinning lines. The results indicated that there were no differences between the hemlock-red spruce and spruce-fir habitats for both relationships of the mean tree volume versus number of trees, and the quadratic mean tree diameter versus number of trees. Thus, these two habitats were combined to develop a single self-thinning line. However, the cedar-black spruce forest habitat required a separate self-thinning line. These maximum size–density relationships can be readily used to construct stand density management diagrams.  相似文献   

14.
甘肃插岗梁自然保护区苔藓植物与针叶林更新关系研究   总被引:2,自引:0,他引:2  
寒温性针叶林是甘肃插岗梁自然保护区内的主要森林植被,苔藓资源十分丰富,形成了苔藓云杉冷杉林以及草类、箭竹云杉冷杉林等丰富多样的林型。以苔藓林分和非苔藓林分为对比,研究了苔藓植物对保护区内寒温性针叶林林木更新的影响。通过对林木萌发质量及数量、土壤含水量、土壤类型、腐殖质、枯枝落叶层有机质含量的调查分析发现,藓类林分相比非藓类林分而言,更有利于树木的生长和更新。  相似文献   

15.
Patterns of tree mortality, rates and type of tree and snag fall, and relationships between snag characteristics and potential wildlife habitat value were estimated for hybrid spruce (Picea glauca (Moench) Voss × engelmannii Parry ex Engelm.) and subalpine fir (Abies lasiocarpa (Hook.) Nutt.) in east-central British Columbia in order to provide important parameters for deadwood modelling. We sampled 172 snags (52 spruce and 120 fir) for species, size, morphological, and habitat attributes, and used dendroecological techniques on a subsample of these (n = 158) to estimate year of death. Input of snags appeared to occur at a nearly constant rate in these stands. Estimated annual tree fall, including live trees and snags, was 5.3% for hybrid spruce and 6.1% for subalpine fir and stem breakage was more frequent than uprooting. Long-term annual snag fall rates were 4.6% for hybrid spruce and 2.9% for subalpine fir. Discriminant analysis based on time since death correctly classified snags into three decay classes for 85% and 72% of spruce and fir, respectively. Snags that potentially could provide important functions for wildlife habitat were more prevalent in fresh and intermediate classes for hybrid spruce and in intermediate and old classes for subalpine fir. The results provide valuable parameters for further development of deadwood models, which are an important tool for development of best practices for deadwood management.  相似文献   

16.
Fine structural studies on the needles of damaged fir (Abies alba Mill.) and spruce [Picea abics (L.) Karst.] trees from forest dieback areas in the Black Forest . The fine structural changes in the variously damaged needles of fir and spruce trees from forest dieback areas have been investigated with special reference to cytoplasmie organization in the vascular bundles, mesophyll tissue and cuticle. The results are compared with those available for a few plants affected both by natural and artificial stress factors, especially air pollutants.  相似文献   

17.
From 2001 to 2003, the litter decomposition dynamics of dominant tree species were conducted using a litterbag burying method in the broadleaf-Korean pine forest, spruce-fir forest and Ermans birch forest, which represents three altitudinal belts in Changbai Mountain, northeast China. The spatial and temporal dynamics of litter decomposition and the effects of litter properties were examined. Furthermore, the decomposition trend of different species was simulated by the Olson model, and results showed that annual mass loss rates increased over time, but was not significantly correlated. Leaf decomposition rates increased after decomposing for 638 days (1.75 years), and the order of dry weight remaining rates of leaf litter for different species is: Asian white birch (Betula platyphylla) (24.56%) < Amur linden (Tilia amurensis) (24.81%) < Korean pine (Pinus koraiensis) (38.48%) < spruce (Picea jezoensis var. microsperma) (41.15%) < Ermans birch (Betula ermanii) (41.53%) < fir (Abies nephrolepis) (42.62%). The dry weight remaining rates of twig litter was smaller than that of leaf litter, and followed the order of Amur linden (44.98%) < fir (64.62%) < Korean pine (72.07%) < spruce (73.51%) < Asian white birch (77.37%) < Ermans birch (80.35%). The simulation results by the Olson model showed that, in leaf, the 95%-decomposition rates ranged from 4.5 to 8.0 years, and annual decomposition rate (k) followed the order of Amur linden (0.686) > Asian white birch (0.624) > Korean pine (0.441) > spruce (0.406) > fir (0.397) > Ermans birch (0.385); in twig, it ranged from 7.8 to 29.3 years, and k follows the order: Amur linden (0.391) > fir (0.204) > Korean pine (0.176) > spruce (0.157) > Asian white birch (0.148) > Ermans birch (0.102). In general, the differences of decomposition rate are evident between leaf and twig litter and among species, and were higher in broad-leaved species compared with coniferous species at the same elevation, and decreased with the ascending of elevation. __________ Translated from Acta Ecologica Sinica, 2006, 26(4): 1,037–1,046 [译自: 生态学报]  相似文献   

18.
Inspection of Norway spruce and Silver fir on experimental plots in south-western Germany showed that Silver fir had suffered significantly less bark injuries than Norway spruce. Data from both federal forest inventories (1987, 2002) showed a similar species-specific vulnerability. Additional visual inspections of the basal cross-sections of trees removed from the experimental plots showed rather high proportions of butt rot in uninjured Norway spruce (51%). The proportion further increased to 93% in trees, which had sustained bark injuries. In contrast, decay symptoms were almost absent in uninjured Silver fir and less enhanced in trees with bark injuries (27%). Management implications for risk rating of tree species, as well as the necessity of implementing low-damage harvesting regimes, are discussed.  相似文献   

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