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1.
正长三角城市群居皖中、苏南、上海、浙北有上百所高校,其中许多相关院校建立了树木园或树木实训基地。根据对上海、南京、扬州、无锡、苏州、杭州、宁波等城市实地调查和参阅有关资料,提出适宜本地区自然地理和气候条件的乡土和外来栽培的归化树种,建设主要植物为北亚热带常绿阔叶、落叶阔叶混交林黄棕壤地带类型,兼有暖温带落叶阔叶林和中亚热带常绿阔叶林的过渡树木种类  相似文献   

2.
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   

3.
对天目山自然保护区8种典型森林类型(杉木林、马尾松林、针阔叶混交林、常绿阔叶林、毛竹林、常绿落叶阔叶混交林、落叶阔叶林、落叶矮林)进行样地调查并计算了各个森林类型乔木层林分密度、物种种类、优势树种、生物量.结果表明,生物量大小顺序为常绿落叶混交林>落叶阔叶林>针阔混交林>杉木林>常绿阔叶林>马尾松林>毛竹林>落叶矮林;在海拔1 000 m以下的5种森林类型,生物量变化不大;而在海拔1000m以上的3种森林类型,随海拔升高生物量下降,物种则增加.  相似文献   

4.
浙江九龙山分布有珍稀濒危落叶树种为主要树种的亚热带常绿落叶阔叶混交林。为探明这些落叶树种在常绿落叶阔叶混交林进展演替过程中生态位变化规律,选择该地区多脉青冈—鹅掌楸林演替过程中4个不同阶段的代表性群落,进展演替过程中,在群落垂直空间上常绿阔叶树不断挤压落叶阔叶树的生存空间,该地区常绿阔叶林顶极群落对珍稀濒危落叶树种是致危生境,不利于生物多样性保护。  相似文献   

5.
通过对定海松林及更新层的调查,发现多数松林在皆伐后演替为落叶阔叶林,少数为常绿落叶阔叶林和灌、草丛。更新树种共计34种,占优势的仅9种,且多为落叶阔叶树种。针对演替类型及更新树种存在单调贫乏的现状,结合海岛具体实际,提出封山育林、人工造林和树种选择的方向性建议,将为松村线虫病除治迹地的更新改造提供依据。  相似文献   

6.
浅谈江苏园林绿化中常绿、落叶树种的配植   总被引:5,自引:1,他引:4  
从常绿、落叶树种的生态习性及江苏省常绿树种的自然分布特点,探讨了落叶、常绿树种在园林绿化中的利用。认为徐淮地区、里下河、滨海盐土区不适宜常绿树种的生长,树种配植应为落叶阔叶树,而盱眙、六合丘陵、宁镇山脉及茅山山脉和长江三角洲丘陵地区可栽植少量耐寒性较强的常绿树种,但应以落叶阔叶树种为主。而在太湖沿岸及宜兴、溧阳较为适宜常绿阔叶树种的生长,可考虑增加常绿阔叶树种的种类及栽培规模。并认为,不必刻意追求单一的景观效果,常绿、阔叶树树种均具园林价值。  相似文献   

7.
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   

8.
常绿和落叶阔叶树叶中N和P的变化及转移   总被引:3,自引:0,他引:3       下载免费PDF全文
薛立  罗山 《林业科学研究》2003,16(2):166-170
从叶完全展开到生长季结束对常绿阔叶树种铁冬青、红楠和海桐及落叶阔叶树种日本朴、银杏和木叶的N和P浓度进行了定期测定。结果表明,常绿阔叶树种新叶的N和P浓度从5—7月急剧下降,然后小幅波动,而老叶的N和P浓度变化缓慢。落叶阔叶树种的N和P浓度随着季节的推移而明显下降。大多数树种的P转移率大于N转移率。常绿阔叶树种的N和P的转移率大于落叶阔叶树种。  相似文献   

9.
薛立  罗山 《林业科学研究》2003,16(2):166-170
从叶完全展开到生长季结束对常绿阔叶树种铁冬青、红楠和海桐及落叶阔叶树种日本朴,银杏和Lai木叶的N和P浓度进行了定期测定。结果表明,常绿阔叶树种新叶的N和P浓度从5-7月急剧下降,然后小幅波动,而老叶的N和P浓度变化缓慢。落叶阔叶树种的N和P浓度随着季节的推移而明显下降。大多数树种的P转移率大N转移率。常绿阔叶树种的N和P的转移率大于落叶阔叶树种。  相似文献   

10.
乳源县五指山林区按垂直分布,其林木复合群落有4种类型:1.常绿阔叶林复合群落;2.常绿阔叶树种与落叶阔叶树种混交林木本群落;3.针阔叶混交林木本群落;4.常绿落叶阔叶矮林复合群落。本文对每种类型的海拔高度、林地土壤和主要树种等分别作了介绍。  相似文献   

11.
通过现场踏勘和典型样地法,对杭州新地标钱江新城CBD公园植物景观进行调查,并对其植物多样性和植物群落结构作了相关分析。结果表明,钱江新城CBD公园现有种子植物60科85属108种(含种以下等级),植物种类比较丰富,其中乔灌草、常绿与落叶乔木、常绿与落叶灌木种类比例较为合理,植物景观表现多样;植物群落结构以复层混交型为主,主要包括落叶阔叶林、常绿阔叶林、常绿落叶阔叶混交林3类,季相景观和生态性较为明显;积极可进入型、消极可进入型、不可进入型3个类型植物空间,分别占22.2%、16.7%、61.1%,绿地空间类型多,但对城市公园来说,可进入型空间比不可进入型空间更重要,应适当增加可进入型植物空间来满足钱江新城CBD公园人口相对集聚性特点。  相似文献   

12.
[Objective]To study the leaf calorific value of different forest types.[Method]This study focused on four common forest types widely distributed across China, including boreal coniferous forest, warm temperate deciduous broad-leaved forest, subtropical evergreen broad-leaved forest, and tropical monsoon forest. The leaf calorific values of 175 dominant (or common) tree species were measured. The leaf calorific value characteristics of the trees found in the different forest types were analyzed, and the primary factors affecting leaf calorific value were investigated, including leaf morphological traits, nutrient elements, climate, and soil traits. [Result]The results showed that in these forest types, the leaf calorific values ranged from 14.84 to 21.98 KJ·g-1, with an overall mean of 19.06 KJ·g-1. The presence of organisms appeared to affect the leaf calorific value, which differed among forest types as follows: coniferous trees > broadleaf trees or evergreen trees > deciduous trees. [Conclusion]The latitudinal pattern of tree leaf calorific value, ordered from north to south, is as follows: warm temperate deciduous broad-leaved forest > subtropical evergreen broad-leaved forest > tropical mountain rainforest. The mean leaf calorific value of boreal coniferous forest was slightly lower than those of warm temperate deciduous broad-leaved forest and subtropical evergreen broad-leaved forest. The leaf calorific values were significantly correlated with leaf carbon content (R2= 0.89, P<0.001). A multiple regression equation was established to describe the relationships among leaf calorific value, leaf carbon content, leaf nitrogen content, and leaf thickness.  相似文献   

13.
The abandonment of sites after clearcutting plantations is increasing rapidly in Japan. Although a few stand-level studies have been conducted, a broad-scale study is needed to understand the general tendency of vegetation recovery and to obtain information for the management of such extensively distributed abandoned clearcut sites. This study is a province-level study that aims to interpret the patterns and factors in early-stage vegetation recovery at abandoned plantation clearcut sites. We also discuss the potential indicators that may determine whether a certain site recovers towards evergreen broad-leaved forest consisting of Castanopsis cuspidata and Quercus glauca or towards deciduous broad-leaved forest comprising Q. serrata and Q. acutissima. A cluster analysis revealed that five types of vegetation (evergreen trees, evergreen trees–deciduous pioneer shrubs, pioneer species, deciduous trees, and deciduous shrubs) were observed from an early stage of succession. The first two vegetation types were considered to recover successfully to the target vegetation of evergreen broad-leaved forest, but the remaining three vegetation types did not show any tendency to recover to the target vegetations. According to the results of the detrended correspondence analysis, a smaller size of the abandoned site with adjacent evergreen broad-leaved forest and a longer time after clearcutting were identified as factors that enhance the invasion of evergreen tree species; these factors are also useful to predict the future successional tendency. In conjunction with these factors, the existence of regeneration sources (i.e., stumps) that allow sprouting appeared to be an important indicator for predicting the early-stage vegetation recovery.  相似文献   

14.
This article reports the regeneration dynamics of a temperate Abies–Tsuga forest in Kirishima Yaku National Park, southwestern Japan, and examines the influence of species coexistence mediated by gap disturbances on biomass production. All trees taller than 2 m in a 1-ha plot were monitored over four growing seasons. Three growth-form groups occupied different vertical layers. Evergreen conifers and deciduous broad-leaved trees tended to be spatially segregated from evergreen broad-leaved trees, which formed thickets in the understorey. The regeneration of understorey evergreen broad-leaved trees was affected by canopy gaps. The recruitment of conifers and deciduous broad-leaved species was not observed during the four growing seasons. This suggests that regeneration is sporadic and the present environmental conditions are not favorable for these canopy species. The mortality and unsuccessful recruitment of conifers and deciduous trees appeared to cause fluctuations in the productivity of the stand. However, an abundance of canopy gaps accelerates the regrowth of shorter species, and the fluctuation of productivity resulting from the population dynamics of canopy species would be partly mitigated by the regeneration of evergreen understorey species. The horizontal and vertical heterogeneity of the temperate mixed forest was a result of the patch structures of the three growth-form groups. The different regeneration patterns among the three groups, which were driven by interactions of species-specific regeneration niches and disturbance regimes, might be an important factor in maintaining the aboveground productivity in a transitional mixed forest between warm-temperate and cool-temperate zones.  相似文献   

15.
金佛山方竹笋用林混交常绿落叶阔叶树效果调查   总被引:2,自引:2,他引:0  
金佛山方竹笋用林混交常绿落叶阔叶树,能够提高光能和营养空间的利用率,有效改善林地的生境,相互之间能起到很好的促进作用,增加方竹出笋力,提高林分质量,具有较高的生产力和显著的经济效益,是方竹笋用林比较理想的经营模式。建议在营造方竹笋用林中混交常绿落叶阔叶树,以短养长、管竹育木,增加经济收益,提高林分的水源涵养功能。  相似文献   

16.
绥宁花园阁国家湿地公园植物资源现状与分析   总被引:1,自引:0,他引:1  
绥宁花园阁国家湿地公园植被丰富,为保护湿地生物资源,采用样方调查与样线调查相结合方法,开展植物资源调查。结果表明:湿地公园有维管束野生植物153科,336属,807种;主要森林类型可分常绿落叶阔叶林、落叶阔叶林、针叶林、竹林、灌草果群系、古树及珍贵树木;其中温带成分最多,植物区系成分以温带性质为主,热带成分也有较高的比例,区系成分出现较强的热带亚热带至温带的过渡性质。  相似文献   

17.
在调查群落种类组成的基础上,对三峡库区3种典型森林主要组成树种的种群结构进行分析,并推断群落的演替趋势.结果表明:1)三峡库区森林群落乔木层优势种主要为马尾松、柏木等针叶树种,短柄袍栎、栓皮栎等落叶阔叶树种及多脉青冈、石栎等常绿阔叶树种;2)针叶群落中乔木层个体高度级频度顶点位于10~15 m,针阔混交群落与阔叶群落为5~10 m;3)阔叶群落中短柄袍栎和栓皮栎等优势种的胸径频率为逆J字型,伴生树种主要为L型或逆J字型,主要组成树种的种群结构表明优势种种群处于稳定状态;4)针阔混交群落针叶优势种的种群属于单峰型和逆J字型的衰退类型,阔叶树种多为逐渐增长的L型或间歇性发展的多峰型;5)针叶群落优势树种胸径频率属于典型的单峰型,伴生树种为单柱型或L型;6)由主要组成树种的种群结构推断三峡库区森林群落演替过程为针叶林群落→针阔混交林群落→常绿阔叶林群落.研究结果为三峡库区生态建设和森林资源管理提供科学依据.  相似文献   

18.
峨眉山常绿阔叶林常绿和落叶物种叶片C、N、P研究   总被引:2,自引:0,他引:2  
采用常规方法对峨眉山常绿阔叶林的常绿和落叶物种植物C、N、P含量及其之间的相互关系进行了研究,结果表明:①峨眉山常绿阔叶林常绿物种叶片C、N、P平均含量分别为42.30%、1.46%、0.10%;落叶物种叶片C、N、P平均含量分别为41.078%、1.59%和 0.12%.常绿和落叶物种植物叶片N-P成极显著的乘幂关系,而C-N和C-P关系不显著;②峨眉山地区常绿阔叶林常绿物种叶片N/P比平均值为14.48,落叶物种的N/P比平均值为13.61,其对生态环境的适应性较低;③在峨眉山海拔700、1 100和1 500 m处,植物叶片N-P亦成显著的关系,而植物叶片C-N和C-P关系不显著.  相似文献   

19.
为全面掌握龙王山自然保护区落叶阔叶林的林分结构特征,设置了3个100m×100m样地,对其中的6个30m×30m样方,进行群落和林分调查。经统计分析,结果表明龙王山落叶阔叶林中树种种类多,优势树种为小叶白辛树和锐齿槲栎,林分树种组成具有一定的复杂性和多样性。林分株数密度平均为1511株/hm2,林分样地间差异不明显。胸径分布呈典型的倒"J"型;树高主要集中在4-9m的树高级,分布则呈偏左的正态分布。林分结构总体上具有多树种复层异龄的基本特征,具有良好的生物多样性保护和植物种质资源保存作用。  相似文献   

20.
Kosugi Y  Matsuo N 《Tree physiology》2006,26(9):1173-1184
Seasonal fluctuations in leaf gas exchange parameters were investigated in three evergreen (Quercus glauca Thunb., Cinnamomum camphora Sieb. and Castanopsis cuspidata Schottky) and one deciduous (Quercus serrata Thunb.) co-occurring, dominant tree species in a temperate broad-leaved forest. Dark respiration rate (Rn), maximum carboxylation rate (Vcmax) and stomatal coefficient (m), the ratio of stomatal conductance to net assimilation rate after adjustment to the vapor pressure deficit and internal carbon dioxide (CO2) concentration, were derived inversely from instantaneous field gas exchange data (one-point method). The normalized values of Rn and Vcmax at the reference temperature of 25 degrees C (Rn25, Vcmax25) and their temperature dependencies (Delta Ha(Rn), Delta Ha(Vcmax)) were analyzed. Parameter Vcmax25 ranged from 24.0-40.3 micromol m(-2) s(-1) and Delta Ha(Vcmax) ranged from 29.1- 67.0 kJ mol(-1). Parameter Rn25 ranged from 0.6-1.4 micromol m(-2) s(-1) and Delta Ha(Rn) ranged from 47.4-95.4 kJ mol(-1). The stomatal coefficient ranged from 7.2-8.2. For the three evergreen trees, a single set of Vcmax25 and Rn25 parameters and temperature dependence curves produced satisfactory estimates of carbon uptake throughout the year, except during the period of simultaneous leaf fall and leaf expansion, which occurs in April and May. In the deciduous oak, declines in Vcmax25 were observed after summer, along with changes in Vcmax25 and Rn25 during the leaf expansion period. In all species, variation in m during periods of leaf expansion and drought should be considered in modeling studies. We conclude that the changes in normalized gas exchange parameters during periods of leaf expansion and drought need to be considered when modeling carbon uptake of evergreen broad-leaved species.  相似文献   

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