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1.
对桉树人工原料林林下植物多样性及多样性与生物量的关系研究概况进行了分析,结果发现:1)大面积单一种植桉树人工林减小了林下植物物种多样性,但通过改进培育手段、科学管理等可以实现桉树人工林的可持续经营;2)桉树人工林林下植物多样性与群落生物量呈现极显著正相关关系,增加桉树人工林物种多样性可以提高林分生物量.  相似文献   

2.
随着大面积规模化的种植,桉树人工林结构过于简单,林下植物多样性低的问题不容忽视。通过对普洱地区桉树人工林与同等条件下的天然林植物种类进行比较,桉树人工林群落物种数量流失,多样性下降和外来物种的入侵,说明一旦种植桉树以后,原有的生态系统都完全改变了,单一栽培桉树树种通常都造成了物种多样性的减少。  相似文献   

3.
为评价幕府山废弃矿地人工林的抚育效果,探讨了不同林分的最佳抚育模式,对林分抚育前后林下植物多样性及土壤养分变化进行了研究。结果表明:科学合理的森林抚育能有效降低林分郁闭度,改善林内光照条件,促进林下植物的更新、生长与演替,提高生物多样性,增强土壤肥力;对林分的人工扰动强度影响林下植物多样性,扰动大则多样性高,但在抚育后1、2年内,林下植物多样性相对不稳定,说明植被群落处于重建和恢复阶段。  相似文献   

4.
本文就滇中桉树人工林纯林、桉树混交林及其它种类的人工林调查材料,对不同林种的群落进行比较,从比较结果中分析桉树人工林生物多样性问题。通过比较分析发现:1、桉树本身的排它现象并不显著;2、桉树林下和松林的林下植物的丰富度相差不多;3、多种按树混交较单一桉树纯林的林下植物丰富。  相似文献   

5.
通过对华南地区阔叶次生林和桉树人工林的林下植物多样性进行调查对比分析,发现次生林林下植物123种,分属52科;桉树人工林林下植物102种,分属49科,两者数量上相差不大,相同的有64种。2个生境物种构成不同,次生林的丰富度指数、均匀度指数、多样性指数均略高于桉树人工林,方差分析显示两者各样方林下植物分布差异显著。2种生境中重要值前10的物种只有3个相同,两者林下植物重要值都集中在前10个物种中,均约占一半。总体上桉树人工林林下植物多样性与次生林的相近。  相似文献   

6.
该研究以桉树纯林、湿地松纯林、混交林的3种林龄阶段林分为对象,探究不同林龄林地土壤因子和林下植物丰富度及重要值,明确林下植物功能群与环境因子之间的关系。结果表明,3种类型林分土壤全氮、全钾、钾氮比与植物功能群重要值都有着显著的相关性,土壤氮元素和钾元素对林下植物群变异都发挥着重要作用。不同林分类型不同林龄人工林林下阳性、耐阴性植物功能群丰富度和重要值都存在显著差异,随着林龄或混交树种增加,耐阴性植物功能群的丰富度增加,重要值降低,群落逐渐向成熟阶段发展。  相似文献   

7.
桉树作为速生树种,是国内木材的主要来源,具有较高的经济价值。但前期无节制的大面积种植,且种植技术不规范,导致桉树人工林土壤结构受到破坏、林下植物多样性下降,破坏生态稳定性,不利于桉树人工林的可持续发展。许多研究者对桉树人工林进行改造,以改善桉树人工林生态环境。该文通过查阅近20年国内桉树人工林改造技术研究文献,分析桉树人工林经营存在的问题及其造成的生态后果,评述桉树人工林改造技术,提出今后桉树人工林改造研究方向的建议。  相似文献   

8.
长江中下游滩地杨树林植物多样性研究   总被引:3,自引:0,他引:3  
本文以3个人工杨树林下植物群落调查样地及原始无林滩地资料为基础,从物种丰富度、均匀度和物种多样性指数等方面对长江中下游江河滩地抑螺防病林试验示范区林下植物群落多样性进行了分析。结果表明,人工林栽植后植物多样性升高了,且不同林龄人工林的植物种类及物种多样性存在差异——3年生的人工林多样性指数最高,8年生的人工林均匀度最高。说明滩地造林明显增加了植物群落的多样性,但随着林分的郁闭会限制其下植物的生长,导致多样性呈下降趋势,可见人工林林分郁闭度左右着林下植物的组成及分布。  相似文献   

9.
通过对昆明市近郊的长虫山和元宝山林区具有代表性的4片不同龄级的华山松人工林进行了调查,并对不同林龄的华山松人工林的群落结构、物种组成,林下植物生活型、生长型进行了分析。研究结果表明,随着林龄的增长,华山松人工林郁闭度及华山松的株数呈现递减趋势,林下植物的科属种数呈现不同程度的增长趋势,但物种多样性仍然低下,50年龄的华山松人工林分的物种多样性仍然显著低于当地的天然林分;林下植物生长型以灌草为主,其中灌木的重要值随林龄的增长而有所增加,林分结构随林龄增长而趋向稳定。  相似文献   

10.
在黄柏山林场4种典型人工林中设置样地,对林下植物组成及多样性进行研究,旨在掌握该区域森林生态系统林下植被特征。研究表明:1)檫杉混交林林下植物丰富度最高。2)4种类型人工林林下物种Shannon-Wiener多样性指数,Simpson多样性指数和均匀度指数均存在显著性差异(p0.05),同时各林分灌木层和草本层植被类型都呈现为中等不相似或极不相似,说明乔木植被类型对于林下物种及其多样性影响较大。在营造人工林时,树种的选择对于其可持续经营有着重要影响作用。3)4种类型人工林林下植被群落多样性指数,包括Shannon-Wiener多样性指数,Simpson多样性指数和均匀度指数均是草本灌木。可能由于4种林分的郁闭度都较高,影响了灌木层生长,同时也为草本层喜阴植物的生长创造了一定条件。在黄柏山林场的人工林经营过程中,应适当进行抚育间伐,增加林内透光度,以利于林下植被的恢复。  相似文献   

11.
选择12和14地位指数的2种立地的林分,分别设置6种和5种保留密度,对间伐4年后的23年生马尾松天然次生林林下植物多样性进行研究。结果表明:马尾松天然次生林林下植物种数随着林分保留密度的增大,12和14地位指数的林分均表现为由逐渐增加至一个峰值后逐渐减少;适宜的保留密度有利于提高林下植物的多样性,12和14地位指数林分的植物多样性分别以保留密度130株/667 m2和100株/667 m2的样地为最优;随着林分密度与冠层郁闭度的增大,林下植物类型有由阳性植物为主向中性与荫性变化的趋势,而形成阳性、中性及荫性共存的多态性植物群落;适宜的保留密度有利于提高林下植物的生物量和植被总盖度,12和14地位指数林分的林下植物生物量和植被总盖度分别以保留密度130株/667 m2和90株/667 m2的样地为最佳;2种地位指数不同保留密度林分的林下枯落物自然风干重、枯落物层厚及腐殖质层厚差异均不显著,而林下地被物鲜重和植被总盖度则均表现为差异极显著。  相似文献   

12.
To reveal the relationship between species diversity and biomass in a eucalyptus (Eucalyptus urophylla × E. grandis) plantation located in the Dongmen State Forestry Farm of Guangxi, south China, 18 sample plots were established and the total biomass, arbor layer biomass and undergrowth biomass of communities were subsequently harvested. The results were as follows: 1) Species richness in eucalypt plantation had remarkable positive correlation with biomass of arbor layer, undergrowth and community (α = 0.001), its correlation coefficients were 0.6935, 0.7028 and 0.7106 respectively. 2) Leaf area index (LAI) had remarkable positive correlation with species richness and undergrowth biomass (α = 0.001). Its correlation coefficients were 0.7310 and 0.6856, respectively. 3) Arbor layer biomass had remarkable correlation with soil organic matter and hydrolysable N, its correlation coefficients was 0.6416 and 0.6203 respectively. Species richness had remarkable correlation with soil organic matter and correlation coefficient was 0.6359. Among them, the correlation was significant at the 0.1 level. Undergrowth biomass had little correlation with nine soil nutrients and correlation coefficients were under 0.4. To sum up, species diversity was advantageous to the promotion of the biomass of the eucalyptus plantation, and the variation of LAI and soil nutrient in small-scales could result in the difference of species diversity and biomass in different sample plots. Translater from Scientia Silvae Sinicae, 2008, 44(4): 14–19 [译自: 林业科学]  相似文献   

13.
[目的]探讨天然次生林和人工林及人工林树种选择对树冠层蚂蚁群落多样性的影响。[方法]运用树栖蚂蚁陷阱法调查云南省绿春县天然次生林和4种人工林的树冠层蚂蚁群落、植物多样性及植物垂直密度变化。[结果](1)共采集蚂蚁标本17 998头,隶属于6亚科29属68种。(2)树冠层蚂蚁多度:紫胶林-玉米混农林紫胶林桉树林橡胶林天然次生林。(3)树冠层蚂蚁丰富度:紫胶林-玉米混农林紫胶林天然次生林橡胶林桉树林。(4)树冠层蚂蚁ACE估计值:紫胶林-玉米混农林紫胶林天然次生林桉树林橡胶林。(5)树冠层蚂蚁多度和丰富度与枯落物盖度、300 cm处垂直密度和乔木郁闭度呈显著或极显著负相关,而与植物盖度显著正相关;ACE估计值与枯落物盖度、草本植物盖度和乔木郁闭度显著负相关,与175 199.9 cm区段内垂直密度显著正相关。[结论]人工林对蚂蚁多样性保护有一定积极作用,尤其选择乡土树种保护效果更显著,对人工林进行合理的管理有利于保护生物多样性。  相似文献   

14.
【目的】研究海拔高度对周公山柳杉人工林林下植物多样性及土壤养分的影响,对人工林的抚育及合理经营有着重要意义,旨在为人工林近自然改造以及利用山地造林、恢复森林生态提供科学依据。【方法】采用代表性样地法和随机取样法相结合的方法,在800、1 000和1 200 m 3个海拔高度对周公山柳杉人工林林下的物种组成、物种重要值、物种多样性和土壤养分进行了初步研究和对比分析。【结果】1)林下草本层共发现植物33种,属于19科32属;林下灌木层共发现植物49种,隶属于39属26科。2)草本群落Shannon-Wiener多样性指数(H)、Simpson优势度指数(H’)和Pielou均匀度指数(JSW)均随着海拔的升高表现为先升高后降低的趋势,符合"中度膨胀"理论,而草本层物种丰富度指数(D)以及灌木层群落各多样性指数则符合负相关关系理论。3)林下植被0~40 cm深度土壤养分随土层深度增加,全氮、全磷、有效磷、速效钾、有机碳、有机质含量均降低。4)物种多样性指数与有机质、全氮(TN)、全磷(TP)、有效磷(AP)的含量呈显著负相关。【结论】应控制人为干扰的强度,保持合理的林分密度,改善柳杉人工林的物种组成和群落结构,使人工林处于一种天然更新状态。  相似文献   

15.
以不同森林经营模式下马尾松天然次生林为研究对象,对经营1年后其林下植被生物量的分布特征进行研究。结果表明:不同经营模式下,马尾松天然次生林下活地被生物量均以灌木层生物量为主,枯落物层生物量对林下植被总生物量的贡献亦大。经营模式为保留密度900株/hm2的马尾松林下植被总生物量最高,而保留密度为2 100株/hm2的马尾松林下植被总生物量最低。保留密度过大或过小林下植被生物量都不高,说明适宜的保留密度才有利于提高马尾松天然次生林下植被的生物量。  相似文献   

16.
Many forest species can be found in understory vegetation of old plantation plots, despite the fact that the native vegetation was a poor savanna growing on highly nonfertile sandy soils. The aim of the present paper is to describe the changes that occur in the environmental conditions when savanna is planted with fast-growing trees, and is particularly concerned with vegetation and soil macrofauna. The study was carried out in industrial eucalyptus plantations, and in experimental Acacia and pine plantations. Most plots were located on sandy soil, but some measurements were also carried out on clay soil planted with the same species in order to assess the influence of soil type.

A strong correlation was shown between the age of the eucalyptus trees and the percentage of forest species in undergrowth, emphasizing the progressive change from savanna vegetation towards forest vegetation.

Biomass and density of macrofauna were very low in both sandy and clayey savanna soils, total biomass being 3.3 and 5.8 g/m2 respectively. Soil macrofauna became more important as the age of plantations increased, and biomass reached 29 g/m2 in the 20-year-old eucalyptus plot on sandy soil, and 74 g/m2 in 26-year-old eucalyptus plantation on clay soil, compared to 33 g/m2 in the natural forest plot on sandy soil; however, frequency of occurrence and number of taxa were lower in old eucalyptus plot as compared to forest. Large differences in the abundance of macrofauna were observed in relation to planted species. Acacia was most favourable to soil macrofauna, with a total biomass of 60 g/m2 on sandy soil and many taxa present. Pine plantations had a poor macrofauna and several taxa were lacking, particularly in the sandy soil.

Total macrofauna frequency was significantly correlated with the percentage of forest species in understory vegetation. Both were correlated with soil pH and soil organic-matter content. The results suggest that soil organic matter and litter quality are of main importance in changing the above- and below-ground habitat in plantations.  相似文献   


17.
杉木林枯枝落叶层现存量的影响因素分析   总被引:1,自引:0,他引:1  
通过收集杉木林枯枝落叶层现存量数据,分析杉木林枯枝落叶层现存量与年平均温度、年降水量、林分年龄、枝叶生物量、凋落物量、林下植被生物量的相关关系。结果表明,杉木林枯枝落叶层现存量与林龄、林下植被生物量、凋落物量、枝叶生物量呈显著正相关,其中与林下植被生物量相关性最大,与年均温呈负相关,而与年降水量无显著相关。多元线性回归分析表明,林龄可单独解释枯枝落叶现存量变化的21.2%,而林龄、降水量、年均温、枝叶生物量可以解释枯枝落叶现存量变化的38.6%。  相似文献   

18.
为适应六盘山水源林可持续经营实践的需求,利用六盘山林业局120个森林连续清查固定样地调查资料,分析了林分郁闭度对林下灌木、草本植物生长影响的规律,建立了适用于当地的数学模型,提出了该区水源林林分的目标层次结构。结果表明:1)该区水源林林分郁闭度影响林下植被的生长,林下灌木层、草本层盖度随林分郁闭度升高而降低;2)该林区水源林林分郁闭度保持在0.5~0.8之间时能够形成明显的乔灌草层次结构,有利于实现水源林经营的生态功能和经济功能的协调;3)该区水源林林分的目标层次结构为,林分郁闭度0.5~0.8,灌木层盖度35%~46%,草本层盖度35%~46%。研究结果可为该区水源林结构调整提供依据。  相似文献   

19.
通过收集杉木林林下植被生物量数据,分析杉木林林下植被生物量与年平均温度、年降水量、林分年龄、林分密度、乔木层生物量、灌木层生物量、草本层生物量、枯枝落叶层现存量等8个因子的相关关系。结果表明,林下植被生物量与林龄、乔木层生物量、灌木层生物量、草本层生物量、枯枝落叶层现存量呈显著正相关,其中以与草本层生物量相关性最大,与林分密度呈负相关,而与年均温、年降水量无显著相关。多元线性回归分析表明,林龄、林分密度、草本生物量可解释枯枝落叶现存量变化的90.6%。  相似文献   

20.
Small-mammal communities were monitored over 4 years in South Moravian rural lowland forests in order to study relationships with various forest habitat types. Early successional sites (plantations) and forest edges maintained communities with higher abundance and diversity. Lowest total abundance was observed in unmanaged lowland forest and highest abundance in plantations with irregular undergrowth management. Low diversity was typical of non-fruiting monocultures. In plantations, both diversity and abundance were affected by herb layer removal, with sites subject to regular cutting, displaying lower levels. Significant differences in diversity and species richness were only detected between early and late successional sites, with the former showing higher values. Two basic small-mammal community groups were determined; (1) those inhabiting sites with a thick herb undergrowth and an open tree canopy (plantation) and (2) those inhabiting stands with sparse or no herb layer and a closed canopy (high forest). Forest stands support long-term populations of dominant small forest-dwelling mammal species and, as such, serve as reservoirs, even in rural landscapes dominated by intensive arable farming. Managed early succession lowland forests represent important refuges for a number of small open-habitat mammals negatively affected by intensive farming.  相似文献   

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