大兴安岭主要森林类型林分空间结构及最优树种组成

以2011—2012年大兴安岭的44块固定样地调查数据为基础,以常用的林分空间结构参数(角尺度、大小比、混交度、林分空间结构指数和林分空间结构距离)为切入点,对大兴安岭主要森林类型的林分空间结构特征及最优树种组成进行研究。结果表明:天然落叶松林、针叶混交林以及针阔混交林的林木水平分布格局均表现为随机分布,而白桦林则为明显的聚集分布;4种林型中树木的生长整体处于中庸状态,落叶松处于明显优势地位,其他伴生树种则处于不同程度受压状态;落叶松混交程度随着其优势程度的增加而降低,其他伴生树种则具有较高的混交度,整体上天然落叶松林、白桦林的树种空间隔离程度较低,而针叶混交林、针阔混交林的林分平均混交度相对较高;大兴安岭4种主要森林类型林分空间结构的优劣表现为针阔混交林针叶混交林天然落叶松林天然白桦林;天然落叶松林最优的树种组成为8落,其次为7落。     

大山冲森林公园亚热带典型天然混交林乔木层更新与演替研究

通过踏查、样地调查相结合的野外调查方法,结合群落重要性指数、相似性指数分析方法,对大山冲森林公园天然的针阔混交群落进行研究,了解其亚热带典型天然混交林的更新和演替规律。结果表明:群落物种组成结构差异在随着时间增加而增大,但总体变幅小,乔木层物种种类增加33.3%,平均胸径、平均树高和林分密度变幅小;4年演替过程中,山矾在群落乔木层中几乎消失,山矾种群数量下降94.4%,青冈栎种群数量相差小,但种群重要值从第三到第五,下降23.4%,丧失了原来的优势地位;群落中,常绿阔叶树种类和针叶树种类变化小或不变,落叶树种类增加了12.5%,但在数量及重要值两方面,常绿阔叶树和针叶树一直处优势地位,石栎和马尾松仍是群落优势种;群落乔木层相似性系数为0.4;在不出现天灾或人类有意干扰下,群落将继续朝顶级群落-常绿阔叶林方向更新演替。     

小兴安岭天然阔叶混交林群落及生长量特征

在小兴安岭伊春林区桃山等5个林业局的林场分别设立了调查试验区,发现5个调查试验区的天然阔叶混交林乔木树种共有12科17属22种,杨柳科、桦木科、椴树科和木樨科在数量上优势比较明显。群落组成的树种以软阔叶树种占多数,但硬阔叶树种也占4成以上,具有明显的向硬阔混交林过渡特征。5个试验区树种混交度均接近强度混交0.75。新青林业局试验区林分主林层林木的各生长因子均表现最好,桃山林业局试验区主林层林分材积最小但演替层林分材积最大。应根据林分的演替状况采用合理营林抚育措施,调整树种组成,逐渐加大针叶树种特别是红松的更新比例,实现"栽针保阔",促进森林演替进程。     

中亚热带2种森林群落组成、结构及区系特征

【目的】研究中亚热带演替阶段相邻的2种森林群落的组成、结构、区系特征,旨在丰富亚热带地区森林动态资料,为加快该地区森林生态恢复和保护生物多样性提供科学依据。【方法】采用空间代替时间方法,结合群落生态学研究方法,在湘中丘陵区选取林龄为45～50年处于演替中期阶段的马尾松+柯(又名石栎)+檵木针阔混交林(PLL)和林龄为80～90年处于演替亚顶极阶段的柯+红淡比+青冈常绿阔叶林(LAG),分别设置3块30 m×30 m固定样地,对胸径≥1 cm的林木进行调查,计算群落多样性指数、特征值和相似系数等指标。【结果】PLL、LAG树种丰富,具有占绝对优势的优势种,且在群落内空间分布比较均匀,LAG树种丰富度和多样性指数高于PLL,且双子叶植物明显增加; PLL、LAG树种组成的差异主要源于乔木树种,特别是常绿阔叶乔木树种,PLL以松科、壳斗科为主,呈现针阔混交林特征,LAG以壳斗科、樟科、漆树科、金缕梅科和八角枫科等常绿阔叶树种为主,呈现常绿阔叶林特征; PLL、LAG的种数和株数垂直结构层次分化明显,LAG各层次树种比PLL更丰富,特别是林下1～5 m层和林冠≥15 m层; PLL、LAG的种数和株数径级结构均呈倒"J"型分布,主要集中在1～8 cm径级; LAG中大径级的种数和株数多于PLL; PLL中,马尾松林下更新失去优势,为衰退型,柯、檵木为增长型,表现出PLL向LAG演替; LAG中,马尾松衰退明显,柯、青冈为增长型,杉木为稳定型; PLL、LAG植物区系以泛热带分布型为主,具有较强热带向温带过渡的性质,LAG热带成分科、属、种多于PLL。【结论】PLL、LAG树种组成、空间结构存在较大差异;亚热带低山丘陵区地带性植被恢复应遵循群落演替动态规律,对已处于演替中期阶段的马尾松针阔混交林可采用封山育林让其自然演替,或通过人工干预(如补植常绿阔叶树种)缩短恢复时间,搭配合理的树种组成,提高林分质量;次生林改造或"针改阔"过程中,应加强泛热带分布型植物的利用,选择起源和演化具有相似性的阔叶树种作为建群种。     

无锡市公园绿地植物群落组成分析

利用植物群落学研究方法,在无锡市公园绿地设立了45个标准样地,对样地群落植物组成、植被类型、结构特征进行了分析。结果表明:所调查样地群落中共有维管束植物319种,隶属于103科235属,占无锡地区现有植物科、属、种的57.22%、26.02%、16.03%,江苏乡土植物203种,占总数63.6%;样地可分为7种植被类型:落叶阔叶型占35.5%、常绿针叶型占17.8%、常绿阔叶型占15.6%、常绿落叶混交型占11.1%、针阔混交型占6.7%、常绿落叶针叶混交型占2.2%;通过乔木层密度、灌木层重要值、乔灌木层树种组成、草本层植物组成分析等得出群落结构特征。最后提出无锡公园绿地植物群落植物组成优化建议。     

不同演替阶段红松阔叶混交林空间结构研究

本文旨在探讨不同演替阶段红松阔叶混交林林分空间结构特征,为明确各林分结构与功能、合理保护和经营红松阔叶混交林提供科学依据。采用TOPCON全站仪在吉林省蛟河市林业实验区管理局不同演替阶段红松阔叶混交林内分别设置4块100 m×100 m监测样地,并进行群落调查,在Visual Studio平台上编写应用程序对不同林分的混交度和大小比数进行计算。结果表明:不同演替阶段林分的平均混交度在0.66和0.78之间,树种之间隔离程度较大;4种林分中树种数量最多的前5个树种平均混交度取值范围为0.69～0.82,其中过熟林最大,近熟林最小,按平均混交度数值大小排序为过熟林中龄林成熟林近熟林。中龄林、近熟林、成熟林和过熟林林分平均胸径大小比数分别为0.48、0.53、0.49、0.49,平均树高大小比数分别为0.48、0.50、0.49、0.49,平均冠幅大小比数分别为0.34、0.42、0.38、0.41。可以看出,胸径和树高平均大小比数取值范围相近,反映林木大小分化程度上具有一致性,而与平均冠幅大小比数取值范围具有一定的差异,说明用树高及胸径计算大小比数得出的结果较冠幅更为可靠。不同演替阶段红松阔叶混交林整体上呈现出一个由不同树种组成、处于强度混交向极强度混交过渡的复杂森林群落,且树种之间大小分化程度明显。     

关帝山次生林区典型植物群落物种多样性垂直分布研究

为了分析和探讨海拔对植物多样性的影响,沿海拔梯度(1600–2600m),设定14个样地,对每个样地内对植物物种进行调查。结果表明:随海拔升高,群落优势种变化依次为:辽东栎、油松、白桦、红桦、华北落叶松和云杉。群落内乔木树种的平均树高和胸径表现为先增大后减小,最大树高和胸径表现为单峰变化。群落内不同生活型树种(针叶树和阔叶树)的最大树高表现为先增大后减小.阔叶树最大胸径无明显变化规律,针叶树最大胸径不断减小。中海拔群落内,针叶树种的最大树高和胸径高于阔叶树种。群落的Shannon-wiener指数和Margalef指数均表现为单峰变化,中海拔群落(1900–2200m)植物多样性最高,高于低海拔群落(1600–1900m)和高海拔群落(2200–2600m)。Shannon-wiener指数和Margalef指数反映出的植物α多样性变化与海拔高度显著相关。在研究地区,植物多样性变化与群落所处的海拔显著相关,此外,还与群落结构、物种组成、树种特性和人为干扰有关。图8表3参13。     

辽东栎群落特征研究及其进展

辽东栎是暖温带落叶阔叶林地区典型群落的建群种,也是该地区针阔混交林的重要组成成分,是较为稳定的森林植物群落。该文就辽东栎的形态特征、更新、种群结构以及群落特征等方面进行了综合评述。辽东栎在不同的发育阶段,在形态建成上具有不同的适应策略,表现出不同的形态特征;而在生境与动物的共同作用下,种子数量和质量受到很大影响,直接影响实生苗的形成从而导致栎林实生更新困难以萌生为主的现象;成熟林种群结构稳定,在分布区内处于优势地位;群落的不同层次在反映处于不同演替阶段群落间存在着较大的差异,而且辽东栎群落演替过程中多样性指数是波动的。通过辽东栎的个体适应、种群分布格局及群落特征、动态的研究,总结其在暖温带生态系统条件下的适应规律,分析其内在机理,从而为保护和扩大辽东栎种质资源及可持续经营提供科学依据。     

辽宁省森林经营区划布局与经营策略

在培育健康稳定森林生态系统的同时,提升森林生态系统的多样性供给能力,为全力推进林业供给侧结构性改革和实现辽宁经济社会可持续发展提供强有力保障。该文主要从森林分类经营、分区施策的角度对辽宁省森林进行了区划布局,即东北中温带针阔混交林经营区和华北暖温带落叶阔叶林经营区。东北中温带针阔混交林经营区进一步划分为经营亚区:辽东山地红松阔叶混交水源涵养林、辽西北阶丘平原松阔混交防风固沙林、辽西丘陵油松栎类混交水土保持林、辽河平原北软阔混交农田河岸防护林;华北暖温带落叶阔叶林经营区进一步划分为经营亚区:凌河源丘陵油松栎类混交水土保持林、辽东湾西部丘陵油松栎类混交海防林、辽河平原南软阔混交农田河岸防护林、辽东半岛丘陵油松栎类混交海防林。各经营亚区按照生态区位、森林类型和经营状况,因地制宜地提出各亚区的经营策略,实施森林分类经营。     

天然次生阔叶混交林空间结构特征分析——以湖北省远安县为例

【目的】研究区域性天然次生阔叶混交林林分组成与空间结构特征,为林分空间结构的优化调整奠定理论基础,指导优化与调节森林空间结构,以获得最佳林分空间分布结构,达到森林经营管理的理想结构目的。【方法】以远安县典型天然次生阔叶混交林为研究对象,布设5个30 m×30 m的固定样地,采用全面调查分析法。对树种组成、林分直径分布、密集度、混交度、大小比和角尺度5个林分空间结构参数进行测定分析,为该区域天然林结构的优化调整提供理论依据和技术支持。【结果】1)样地调查乔木层物种13科22属31种,林分主体为落叶阔叶混交林生态群落;林木径级株数分布遵从异龄林型。2)各树种密集度频率值分布在0.75～1.00之间,平均密集度为0.98。3)各树种平均混交度频率值为0.55～1.00,平均混交度频率值为0.79。4)各树种的平均胸径大小比平均频率分布在0.25～0.92之间,平均胸径大小比值为0.5。5)各树种平均角尺度值分布在0.13～0.54之间,综合平均角尺度值为0.48。【结论】该区域天然次生阔叶混交林群落物种组成丰富,结构复杂,树种组成搭配复杂,林分组成以壳斗科阔叶混交林为代表的优势树种占主体地位和生态空间;林分直径分布符合天然林径级特征;林分处于比较密集与很密集水平之间,为强度混交,混交状况较好,种群隔离程度较高;各树种空间大小分化和大小组合存在差异,既占优势也有受压,整体林分处于中庸和优势状态;天然次生阔叶混交林因树种不同,分布格局而不同,随机、团状、均匀并存,林分分布格局整体呈现随机分布。     

Hydraulic conductivity, photosynthesis and leaf water balance in six evergreen woody species from fall to winter

To confirm that freeze-thaw embolism is a primary stress for evergreen woody species in winter, hydraulic conductivity, photosynthesis and leaf water potential were measured during fall and winter in trees growing in a cool temperate zone (Nikko) and in a warm temperate zone (Tokyo). We examined two evergreen conifers that naturally occur in the cool temperate zone (Abies firma Siebold & Zucc. and Abies homolepis Siebold & Zucc.), and four evergreen broad-leaved woody species that are restricted to the warm temperate zone (Camellia japonica L., Cinnamomum camphora (L.) J. Presl, Ilex crenata Thunb. and Quercus myrsinaefolia Blume). In Tokyo, where no freeze-thaw cycles of xylem sap occurred, hydraulic conductivity, photosynthesis and water balance remained constant during the experimental period. In Nikko, where there were 38 daily freeze-thaw cycles by February, neither of the tracheid-bearing evergreen conifers showed xylem embolism or leaf water deficits. Similarly, the broad-leaved evergreen trees with small-diameter vessels did not exhibit severe embolism or water deficits and maintained CO(2) assimilation even in January. In contrast, the two broad-leaved evergreen trees with large-diameter vessels showed significantly reduced hydraulic conductivity and shoot die-back in winter. We conclude that freeze-thaw embolism restricts evergreen woody species with large-diameter vessels to the warm temperate zone, whereas other stresses limit the distribution of broad-leaved trees, that have small-diameter vessels, but which are restricted to the warm temperate zone.     

浙南次生阔叶林群落结构特征研究

浙南次生阔叶树种资源丰富,常见的自然恢复乔木阔叶树种达60余个,频度大于10%的有青冈、木荷、苦槠、白栎、甜槠、枫香、红楠、野漆、栲树、樟、冬青、檫木、野柿和杨梅14个;但树种总量较为集中,其中青冈、木荷、苦槠和白栎4个树种的立木总量占全部阔叶树种的65.14%。天然恢复条件下林分一般由1～5个乔木树种组成,其中乔木树种4个以下的占48.3%,乔木阔叶树种4个以下的占乔木树种4个以下的57.4%,只有10%的样地乔木树种数量超过10个;单位面积的乔木树种在3000株/hm2以下的占89.9%,不足2000株的占78.7%,1000株以下的占32.6%。根据各样地乔木层主要树种的重要值,浙南次生常绿阔叶林中青冈、苦槠、木荷、甜槠、枫香、石栎、米槠等种群为群落的优势种群。     

江苏宜兴市龙池山银缕梅种群的生态位研究

以江苏省无锡市宜兴林场龙池山的银缕梅种群为研究对象,通过5块调查样地,采用7个计算公式,对生态位开展了研究,结果表明:江苏宜兴市龙池山群落中银缕梅的生态位宽度小于青冈和其它阔叶树种;银缕梅与青冈、银缕梅与其它阔叶树、青冈与其它阔叶树的生态位相似性比例均小于0.5;银缕梅、青冈及其它阔叶树种间生态位重叠值的大小反映了各树种在不同层次上利用资源的相似程度;按Shannon-Wiener公式计算的生态位宽度比按Levins公式计算的生态位宽度更能体现树种间生态位的差别;青冈在群落中是优势种群,而银缕梅居于次要和从属的地位.     

Effects of topography and planted trees on the distribution of naturally regenerated broad-leaved trees in a 140-year-old <Emphasis Type="Italic">Cryptomeria japonica</Emphasis> plantation in northern Kyushu,Japan

We investigated factors affecting the distribution of naturally regenerated broad-leaved trees in a 140-year-old Cryptomeria japonica plantation. We used path analysis to examine the relationship among microtopography, the biomass of planted trees, and the biomasses of canopy and subcanopy trees of broad-leaved species. The study plot was divided into three topographic types (ridge, slope, and valley), and we discuss how the different topographic types are affected. For all topographic types, the biomass of canopy trees of broad-leaved species decreased with convexity. For slope and valley topographies, the biomass of subcanopy trees of broad-leaved species also decreased with convexity. For ridge topography, the biomass of subcanopy trees of broad-leaved species increased with the biomass of planted trees, and decreased with the biomass of canopy trees of broad-leaved species. These results suggest the effects of microtopography on the biomass of subcanopy trees were much larger than the effects of canopy trees for slope and valley topographies, while the effects of microtopography were smaller for ridge topography.     

厦门市山地植被的群落结构分析

对厦门市山地植被的群落结构分析结果表明,厦门市山地植物群落在外观主要表现为常绿阔叶林相,以常绿阔叶树种为主,其植被以台湾相思群落为主;在乔灌木树种组成上,乔木层优势种主要有台湾相思、朴树、马尾松、土蜜树和榕树等,灌木层优势种主要有豺皮樟、大青、牡荆、桃金娘、黄栀子、盐肤木等,同时,也分析了厦门市山地植被的生物多样性。       

The diversification of terpene emissions in Mediterranean oaks: lessons from a study of Quercus suber, Quercus canariensis and its hybrid Quercus afares

Interspecific gene flow is common in oaks. In the Mediterranean, this process produced geographical differentiations and new species, which may have contributed to the diversification of the production of volatile terpenes in the oak species of this region. The endemic North African deciduous oak Quercus afares (Pomel) is considered to be a stabilized hybrid between the evergreen Quercus suber (L.) and the deciduous Quercus canariensis (Willd.), presumably being monoterpene and isoprene emitters, respectively. In a common garden experiment, we examined the terpene emission capacities, terpene synthase (TPS) activities and nuclear genetic markers in 52 trees of these three oak species. All but one of the Q. suber and Q. canariensis trees were found to be genetically pure, whereas most Q. afares trees possessed a mixed genotype with a predominance of Q. suber alleles. Analysis of the foliar terpene emissions and TPS activities revealed that all the Q. canariensis trees strongly produced isoprene while all the Q. suber trees were strong monoterpene producers. Quercus afares trees produced monoterpenes as well but at more variable and significantly lower rates, and with a monoterpene pattern different than that observed in Q. suber. Among 17 individuals tested, one Q. afares tree emitted only an insignificant amount of terpenes. No mixed isoprene/monoterpene emitter was detected. Our results suggest that the capacity and pattern of volatile terpene production in Algerian Q. afares populations have strongly diverged from those of its parental species and became quantitatively and qualitatively reduced, including the complete suppression of isoprene production.     

雷波西宁古茶树居群分类与排序及物种多样性研究

对雷波西宁野生古茶树群落分布区进行群落学调查,共设置了37个群落样地(20 m×20 m)进行了DCA分类与排序分析;同时,利用丰富度指数(R)、辛普森指数(D)、香农-维纳指数(H)和Alatalo均匀度指数(E)分析了不同群落类型间的物种多样性。研究结果表明:通过DCA群落分类方法将古茶树群落分为6种类型,即Ⅰ茶树+枹栎+扁刺栲群落、Ⅱ茶树+丝栗栲+曼青冈群落、Ⅲ茶树+锐齿槲栎+白栎群落、Ⅳ茶树+柳杉+红椿群落、Ⅴ茶树+亮叶桦+野核桃群落、Ⅵ茶树+桤木+檫木群落。总体以常绿与落叶阔叶混交林为主,也有少量常绿阔叶林和人工柳杉林。样方的DCA排序明确地揭示各群落类型境地分布范围;样地和物种DCA排序较好地揭示立地因子对群落类型和物种分布格局的影响。从群落相似性和稳定性角度出发,野生古茶树首要应开展就地保护,尽量避免人为干扰,同时加大人工繁育研究。     

Wildlife species associated with non-coniferous vegetation in Pacific Northwest conifer forests: A review

Non-coniferous vegetation, including herbs, shrubs, and broad-leaved trees, makes a vital contribution to ecosystem function and diversity in Pacific Northwest conifer forests. However, forest management has largely been indifferent or detrimental to shrubs and trees that have low commercial value, in spite of a paradigm shift towards more holistic management in recent decades. Forest management practices that are detrimental to broad-leaved trees and shrubs are likely to decrease habitat diversity for wildlife, but the number of species that may be affected has not previously been enumerated. I reviewed life history accounts for forest-dwelling vertebrate wildlife species and derived a list of 78 species in Oregon and Washington that are associated with non-coniferous vegetation. The diversity of direct and indirect food resources provided was the primary functional basis for associations of most species with non-coniferous vegetation. Thus, a diversity of herbs and broad-leaved trees and shrubs provides the foundation for food webs that contribute to diversity at multiple trophic levels in Pacific Northwest conifer forests. Given the number of species associated with non-coniferous vegetation in conifer-dominated forests, maintaining habitats that support diverse plant communities, particularly broad-leaved trees and shrubs, will be an important component of management strategies intended to foster biodiversity. Silvicultural practices such as modified planting densities, and pre-commercial and commercial thinning, can be used to control stand density in order to favor the development of understory herbs, shrubs, and a diversity of tree species within managed stands. Allowing shrubs and hardwood trees to develop and persist in early seral stands by curtailing vegetation control also would benefit many species associated with non-coniferous vegetation.     

太子山几种阔叶树种测树因子相关性分析

以太子山常见的阔叶树种枫香树、麻栎及红果冬青为研究对象,采用SPSS分析胸径(D)与基部直径(Di)、树高(H)与胸径(D)、冠径(Cw)与胸径(D)等之间相关关系,结果表明:测树因子间存在极显著相关关系,各树种距离地面不同高处基径与胸径均呈线性相关,其中以D-D_0.50模型拟合效果最好;树高与胸径、冠径与胸径也均为线性相关。