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1.
Diversity of Medicinal Plants among Different Forest-use Types of the Pakistani Himalaya Medicinal plants collected in Himalayan forests play a vital role in the livelihoods of regional rural societies and are also increasingly recognized at the international level. However, these forests are being heavily transformed by logging. Here we ask how forest transformation influences the diversity and composition of medicinal plants in northwestern Pakistan, where we studied old-growth forests, forests degraded by logging, and regrowth forests. First, an approximate map indicating these forest types was established and then 15 study plots per forest type were randomly selected. We found a total of 59 medicinal plant species consisting of herbs and ferns, most of which occurred in the old-growth forest. Species number was lowest in forest degraded by logging and intermediate in regrowth forest. The most valuable economic species, including six Himalayan endemics, occurred almost exclusively in old-growth forest. Species composition and abundance of forest degraded by logging differed markedly from that of old-growth forest, while regrowth forest was more similar to old-growth forest. The density of medicinal plants positively correlated with tree canopy cover in old-growth forest and negatively in degraded forest, which indicates that species adapted to open conditions dominate in logged forest. Thus, old-growth forests are important as refuge for vulnerable endemics. Forest degraded by logging has the lowest diversity of relatively common medicinal plants. Forest regrowth may foster the reappearance of certain medicinal species valuable to local livelihoods and as such promote acceptance of forest expansion and medicinal plants conservation in the region. 相似文献
2.
The arboreal ant communities of a primary lowland rain forest and three differently disturbed forests that lie close together
forming an anthropogenic disturbance gradient were collected with insecticide fogging. Combined samples from all trees (87
foggings) comprised 153,504 ants sorted to 331 morphospecies. The primary forest ant fauna was characterized by high species
richness and 53 foggings were necessary to collect communities representatively. Another 63 species of ants were found in
the disturbed forests indicating a large regional species pool that might exceed 420 species of arboreal ants. Anthropogenic
disturbance caused a change in the taxonomic composition, diversity and structure of ant communities. Community size was a
predictor of species richness in the severely disturbed forest types but not in the old secondary or primary forest. Ant abundance
had declined significantly in the disturbed forests and only 10% of the primary forest’s species were collected in the most
disturbed forest type. In each of the secondary forests a change in the frequency distribution of species was observed and
a small number of species had gained numerical dominance. Analysis of species associations indicates that the strength of
species interactions changed with the degree of forest disturbance. These changes were still clearly recognizable after 40
years of forest regeneration despite optimal conditions for colonization from the adjacent primary forest, demonstrating that
the time scale needed for forest recovery after anthropogenic disturbance is very long. 相似文献
3.
The Tropical managed Forests Observatory: a research network addressing the future of tropical logged forests
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Plinio Sist Ervan Rutishauser Marielos Peña-Claros Alexander Shenkin Bruno Hérault Lilian Blanc Christopher Baraloto Fidèle Baya Fabrice Benedet Katia Emidio da Silva Laurent Descroix Joice Nunes Ferreira Sylvie Gourlet-Fleury Marcelino Carneiro Guedes Ismail Bin Harun Riina Jalonen Milton Kanashiro Haruni Krisnawati Mrigesh Kshatriya Philippa Lincoln Lucas Mazzei Vincent Medjibé Robert Nasi Marcus Vinicius N. d'Oliveira Luis C. de Oliveira Nicolas Picard Stephan Pietsch Michelle Pinard Hari Priyadi Francis. E. Putz Ken Rodney Vivien Rossi Anand Roopsind Ademir Roberto Ruschel Nur Hajar Zamah Shari Cintia Rodrigues de Souza Farida Herry Susanty Eleneide Doff Sotta Marisol Toledo Edson Vidal Thales A.P. West Verginia Wortel Toshihiro Yamada 《应用植被学》2015,18(1):171-174
While attention on logging in the tropics has been increasing, studies on the long-term effects of silviculture on forest dynamics and ecology remain scare and spatially limited. Indeed, most of our knowledge on tropical forests arises from studies carried out in undisturbed tropical forests. This bias is problematic given that logged and disturbed tropical forests are now covering a larger area than the so-called primary forests. A new network of permanent sample plots in logged forests, the Tropical managed Forests Observatory (TmFO), aims to fill this gap by providing unprecedented opportunities to examine long-term data on the resilience of logged tropical forests at regional and global scales. TmFO currently includes 24 experimental sites distributed across three tropical regions, with a total of 490 permanent plots and 921 ha of forest inventories. 相似文献
4.
该文针对“西双版纳热带山地雨林的植物多样性研究”论文中存在的一些问题进行了讨论。原文所依据的6个调查样地, 从其分布海拔、生境、群落的生态外貌特征、植物区系组成及单位面积植物种数的统计上反映出它们并非都属于同样的植被类型,即原文所称的热带山地雨林,而可能分别属于《云南植被》中所应用的热带季节雨林的次生林群落(样地I和II)、季风常绿阔叶林群落(样地V和VI)及类似于苔藓常绿阔叶林(样地III和IV)的群落类型。由于这些样地代表了不同的植被类型, 导致在对这些样地的植物多样性特征的比较上出现较大差异。对原文在资料分析和与其它森林群落植物多样性的比较上存在的一些问题也作了讨论。原文的研究结果显示了西双版纳不同海拔高度上森林植物群落的物种多样性特征,但并不能全部运用于该地区的热带山地雨林这一特定植被类型。 相似文献
5.
High compatibility between arbuscular mycorrhizal fungal communities and seedlings of different land use types in a tropical dry ecosystem 总被引:1,自引:1,他引:0
Gavito ME Pérez-Castillo D González-Monterrubio CF Vieyra-Hernández T Martínez-Trujillo M 《Mycorrhiza》2008,19(1):47-60
We conducted this study to explore limitations for the establishment of mycorrhizal associations in disturbed areas of the tropical dry ecosystem in the Chamela region of Jalisco, Mexico. Specifically, we: (1) assessed the diversity and composition of arbuscular mycorrhizal fungal (AMF) communities through spore morphospecies identification in three common land uses (primary forest, secondary forest, and pasture), (2) tested the inoculum potential of the AMF communities and the effect of water stress on the establishment of mycorrhizal associations in seedlings of various plant species, and (3) explored the importance of AMF community composition on early seedling development. Soil and root samples were taken from 15 random points in each of three plots established in two primary forests, two 26-year-old secondary forests, and two 26-year-old pastures. We expected that because of soil degradation and management, pastures would have the lowest and primary forests the highest AMF species richness. We found evidence for changes in AMF species composition due to land use and for higher morphospecies richness in primary forests than in secondary forests and pastures. We expected also that water stress limited plant and mycorrhizal development and that plants and AMF communities from secondary forests and pastures would be less affected by (better adapted to) water stress than those from the primary forest. We found that although all plant species showed biomass reductions under water stress, only some of the plant species had lower mycorrhizal development under water stress, and this was regardless of the AMF community inoculated. The third hypothesis was that plant species common to all land use types would respond similarly to all AMF communities, whereas plant species found mainly in one land use type would grow better when inoculated with the AMF community of that specific land use type. All plant species were however equally responsive to the three AMF communities inoculated, indicating that all plants established functionally compatible AMF in each community, with no preferences. The results suggest that early seedling growth and mycorrhizal development in secondary forests and pastures is not likely limited by diversity, quantity, or quality of mycorrhizal propagules but by the high temperature and water stress conditions prevailing at those sites. 相似文献
6.
Diversity and abundance of vascular epiphytes: a comparison of secondary vegetation and primary montane rain forest in the Venezuelan Andes 总被引:5,自引:0,他引:5
Barthlott Wilhelm Schmit-Neuerburg Viviane Nieder Jürgen Engwald Stefan 《Plant Ecology》2001,152(2):145-156
Species diversity of vascular epiphyte plant communities was studied in La Carbonera, a montane rain forest dominated by Podocarpaceae in the Venezuelan Andes. We compared the epiphyte communities of the primary, disturbed, and secondary forest areas of La Carbonera in order to augment the scarce knowledge on the effects of anthropogenic disturbance on these important elements of tropical vegetation. Diversity of vascular epiphytes (191 species in the whole forest area) was low in the disturbed and secondary areas (81 spp.) compared to adjacent primary forest (178 spp.). Four types of disturbed forest and secondary vegetation supported different numbers of epiphyte species, showing a decline with increasing degrees of disturbance (65 spp. along a road transect, 42 spp. on relict trees in disturbed forest, 13 spp. in a tree plantation and 7 spp. in a former clearing, both secondary vegetation units). Epiphytic species composition in primary and disturbed or secondary forest areas differed markedly: disturbed habitats harboured fewer fern and orchid species but more bromeliad species than the primary forest. Probably the families occurring only in primary forest sites of our study may be useful as bioindicators to determine the degree of disturbance in other habitats of mountain rain forests as well. Epiphyte abundance was also lower in disturbed habitats: a remnant emergent tree supported only about half as many epiphyte individuals as a member of the same species of similar size in the primary forest. The decrease in species numbers and abundance as well as the differences in species composition are mainly due to the less diverse phorophyte structure and less differentiated microclimate in the disturbed and secondary vegetation compared to the primary forest. 相似文献
7.
This study documents the abundance, distribution and knowledge of medicinal plant species in a Ransa Dayak village and adjoining
forest in West Kalimantan, Indonesia. Over 250 medicinal plant species from 165 genera and 75 families are utilized by the
local healer. Late successional, primary and river bench forests contained the highest diversity of locally-utilized medicinal
species and the greatest number of species restricted to a single forest type for which alternative species or remedies were
unavailable. Epiphytes and trees restricted to primary forests are particularly important sources for plants used to treat
unusual ailments. A 100% survey of village residents 15 years of age and older (N = 32) revealed that people older than 25
years of age, and older females in particular, possessed greater knowledge of medicinal plants and their uses than younger
people and males. All residents, except the male healer, were more knowledgeable about medicinal plants found in early successional
forests than those of primary forests. Commercial logging and the loss of traditional knowledge through acculturation pose
twin challenges to the persistence of traditional medicinal plant use in this Ransa village and throughout much of Kalimantan.
Résumé Penelitian ini mengumpulkan informasi mengenai keberadaan, penyebaran dan pengetahuan tentang jenis tumbuhan obat di daerah perkampungan Daya’ Ransa dengan hutan sekitarnya di Kalimantan Barat, Indonesia. Lebih dari 250 spesies tumbuhan obat dari 165 genus dan 75 suku digunakan oleh dukun setempat. Hutan sekunder tua, hutan primer dan daerah hutan sepanjang pinggir sungai merupakan tipe hutan yang memiliki keanekaragaman dan jenis tumbuhan obat paling tinggi yang hanya tumbuh di tipe hutan tersebut serta tidak adanya jenis tumbuhan obat pengganti untuk mengobati penyakit yang sama di tipe hutan lain. Jenis epipit dan pohon yang ditemukan khusus di hutan primer mempunyai arti sangat penting bagi masyarakat karena digunakan untuk menogobati jenis penyakit yang tidak biasa. Dari survey 100% yang dilakukan terhadap penghuni desa yang usianya lebih dari 15 tahun (N = 32) diketahui bahwa penduduk yang berusia lebih dari 25 tahun, terutama perempuan berusia tua, mempunyai pengetahuan yang lebih banyak mengenai pemanfaatan tumbuhan obat dibandingkan dengan laki-laki dan perempuan yang lebih muda. Seluruh penduduk, kecuali sang dukun, lebih mengetahui pemanfaatan tumbuhan obat yang tumbuh di hutan sekunder muda dibandingkan dengan tumbuhan obat yang tumbuh di hutan primer. Kegiatan pembalakan hutan berskala besar (HPH) dan hilangnya pengetahuan tradisional lewat perubahan budaya adalah dua tantangan yang dihadapi untuk dapat mempertahankan pemakaian dan melestarikan tumbuhan obat di kampung ini khususnya dan di seluruh Kalimantan umumnya.相似文献
8.
Tropical rain forest fragmentation and its ecological and species diversity changes in southern Yunnan 总被引:6,自引:2,他引:4
Three fragmented rain forests and one primary forest in southern Yunnan were plotted. The microclimate and soil conditions of these forests were also studied. The following conclusions were drawn: (1) The microclimatic differences between inside and outside forest are less in the fragmented forests than in the primary forest, which indicates that the buffer effects to climatic change have been reduced in the fragmented forests. The soil has deteriorated to some extent due to forest fragmentation. (2) In species composition, especially the abundance of some species and the dominant ranks of some families have changed with fragmentation. Barringtonia macrostachya, the most dominant species in the control primary forest, disappeared from the fragmented forests, while Antiaris toxicaria, which is a characteristic but not dominant species in the primary forest, is dominant in fragmented forests. (3) The total number of species per plot was reduced in the fragmented forests and the more seriously disturbed the fragment was, the more the species richness diminished. (4) In life form spectra, the liana and microphanerophyte species increased, but epiphyte, megaphanerophyte, mesophanerophyte and chamaephyte species decreased in the fragmented forests. (5) The plant species diversity is generally lower in the fragmented forests than in the primary forest, although for some life forms it could be higher. (6) The tree species with small populations could be lost first in the process of rain forest fragmentation. (7) The heliophilous or pioneer tree species increased and the shade-tolerant species were reduced in the fragmented forests. 相似文献
9.
Integrating conservation goals with the sustainable use of tropical rain forests has received much attention in recent decades.
Amomum villosum, a traditional Chinese medicinal herb, has been cultivated in the understory of seasonal rain forest for 40 years in Xishuangbanna,
Southwest China. Cultivated area has reached 58.11 km2 much of which is distributed within nature reserves. This practice has caused controversy on whether A. villosum cultivation would alter the structure and function of the primary forest. This study examined the effects of medicinal plant
cultivation on seasonal rain forest by comparing plant diversity, biomass, litterfall and soil nutrients of primary rain forest
with disturbed areas where A. villosum is cultivated. The results indicate that plant diversity, tree biomass, litter production and soil nutrients are significantly
lower in the disturbed than in the primary rain forest. These results suggest that the cultivation of A. villosum affects the structure and function of the seasonal rain forest in Xishuangbanna. 相似文献
10.
浙江省金华北山地处中亚热带北部, 在植被区划上属于中亚热带常绿阔叶林北部亚地带。该区植被是遭砍伐后恢复的次生林, 目前正处于快速的正向演替进程中, 这为研究常绿阔叶林植物群落动态演替机制及受损生态系统的恢复提供了平台。为进一步了解金华北山地区主要植被类型的群落特征, 该文以国际上通用的大样地调查方法, 采用固定样方对其南坡主要植物群落进行了调查, 其中森林样方面积30 m × 30 m, 灌丛样方面积为20 m × 10 m、30 m × 10 m。调查群落物种组成及其数量特征, 记录群落生境信息, 计算木本植物重要值, 分析群落的类型及特征, 并制作每个样方主要木本植物的空间分布图。论文提供了24组详细的群落样方数据(包括21个森林样方和3个灌丛样方), 含有11个群系。 相似文献
11.
喀斯特峰丛洼地不同类型森林群落的组成与生物多样性特征 总被引:3,自引:0,他引:3
不同退化程度石漠化生态重建的关键是恢复植被, 提高土地生产力。本文基于动态监测样地(200 m × 40 m)植被的全面调查, 研究了喀斯特峰丛洼地人工林、次生林和原生林3类典型森林群落木本植物的组成与生物多样性特征。结果表明, 3类森林的物种组成分别为26科52属65种、33科68属100种和43科91属123种, 常绿物种分别占41.54%、47.00%和52.85%; 科、属、种和生活型组成复杂, 优势科或种明显, TWINSPAN分类第3级水平上可分别划分为8、9和8个群落类型。原生林多样性和结构性指标均高于人工林和次生林, 人工林的Shannon-Wiener指数、Simpson指数、均匀度、冠幅、胸径和树高均高于次生林, 而种类、密度和盖度则低于次生林。不同类型森林群落特征不同, 应采取相应的经营策略。 相似文献
12.
Plant composition associated with environmental gradients in tropical montane forests (Cueva de Los Guacharos National Park,Huila, Colombia)
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Niche differentiation among tropical forest plants can generate species turnover along gradients of soil, topography, climate, and land use history. In this study we explore the relative importance of these variables as drivers of floristic composition in Cueva de Los Guacharos National Park. We established twenty 0.1‐ha plots, within which trees, lianas, and shrubs (diameter ≥ 2.5 cm) were censused. We selected plot locations in primary and disturbed forests, and we measured topography and soil variables. Despite their structural similarity, primary and disturbed forests differed floristically, and also differed in environmental variables measured. A NMDS ordination showed that variation in the floristic composition across plots is highly correlated to the exchangeable acidity, elevation, temperature, and magnesium availability. Variance partitioning analysis shows that together spatial and environmental variables explain 24.2 percent of the variation in species composition. ‘Pure environmental’ variables were more important in explaining compositional variability than ‘pure spatial’ processes (9.8% and 1.4%, respectively). Residual variance may be attributed to stochastic process or non‐measured biotic effects. 相似文献
13.
西双版纳傣族“龙山”片断热带雨林植物多样性的变化研究 总被引:10,自引:0,他引:10
本文选择了西双版纳地区6个傣族“龙山”片断热带雨林和一个同样植被类型的自然保护区原始林为研究样地,在各样地中均设置一个2500m2面积的样方,采用植物群落学与植物种类编目相结合的方法,比较研究了各“龙山”片断雨林的群落结构(层次和覆盖度),植物丰富度(单位面积上的植物个体数)和物种多样性指数的变化情况,得出结论:随着隔离(孤立)时间的增加和人为干扰的加剧,“龙山”片断热带雨林的群落结构和植物丰富度将越趋偏离原始热带雨林,亦即群落结构变得不完整,植物丰富度降低,以及物种多样性指数显著下降,片断热带雨林中的雨林成分也将在一定程度上被先锋成分等其它植被类型成分替换。本文也对导致这些变化的原因作了探讨。 相似文献
14.
Peatland forests are the least diverse tree communities documented in Amazonia,but contribute to high regional beta‐diversity
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Frederick C. Draper Eurídice N. Honorio Coronado Katherine H. Roucoux Ian T. Lawson Nigel C. A. Pitman Paul V. A. Fine Oliver L. Phillips Luis A. Torres Montenegro Elvis Valderrama Sandoval Italo Mesones Roosevelt García‐Villacorta Fredy R. Ramirez Arévalo Timothy R. Baker 《Ecography》2018,41(8):1256-1269
Western Amazonia is known to harbour some of Earth's most diverse forests, but previous floristic analyses have excluded peatland forests which are extensive in northern Peru and are among the most environmentally extreme ecosystems in the lowland tropics. Understanding patterns of tree species diversity in these ecosystems is important both for quantifying beta‐diversity in this region, and for understanding determinants of diversity more generally in tropical forests. Here we explore patterns of tree diversity and composition in two peatland forest types – palm swamps and peatland pole forests – using 26 forest plots distributed over a large area of northern Peru. We place our results in a regional context by making comparisons with three other major forest types: terra firme forests (29 plots), white‐sand forests (23 plots) and seasonally‐flooded forests (11 plots). Peatland forests had extremely low (within‐plot) alpha‐diversity compared with the other forest types that were sampled. In particular, peatland pole forests had the lowest levels of tree diversity yet recorded in Amazonia (20 species per 500 stems, Fisher's alpha 4.57). However, peatland pole forests and palm swamps were compositionally different from each other as well as from other forest types in the region. Few species appeared to be peatland endemics. Instead, peatland forests were largely characterised by a distinctive combination of generalist species and species previously thought to be specialists of other habitats, especially white‐sand forests. We suggest that the transient nature and extreme environmental conditions of Amazonian peatland ecosystems have shaped their current patterns of tree composition and diversity. Despite their low alpha‐diversity, the unique combination of species found in tree communities in Amazonian peatlands augment regional beta‐diversity. This contribution, alongside their extremely high carbon storage capacity and lack of protection at national level, strengthens their status as a conservation priority. 相似文献
15.
In a Mapuche community situated in the sub-antarctic forest of the northwest of Argentine Patagonia, analysis was carried
out on forest environmental perception and its relation to the resilience of the body of traditional botanical knowledge regarding
medicinal plants. Data was obtained on the ethno-classification and differential use of the forest gathering environment with
respect to its practical and cultural value. Semi-structured interviews were carried out with 30 randomly chosen inhabitants,
and the data were analysed using qualitative methods and non-parametric statistics. Most citations (64.5%) were of species
gathered in Nothofagus antarctica forest, 26.2% were of species from N. pumilio forest, and 20.3% referred to species from a mixed forest, with N. dombeyi. The forests studied have low values for similarity in terms of medicinal species richness, indicating a unique offer of
therapeutic resources in each one. The use of the different forest types seems to be associated with the search for therapeutic
resources for specific ailments. However, the redundancy of functions of species in each forest type can offer alternative
remedies, which provides plant conservation, security and the possibility of reorganisation of their traditional medicinal
knowledge. This case study showed the importance of considering folk systems and the role that this knowledge has played in
plant resource management and forest protection. Different forests are used and valued differentially, not only with regard
to usefulness but also in symbolic-religious terms, and together they fulfil a cushioning function, protecting holistically
traditional botanical knowledge, people’s health and forests. It is of great importance, therefore, that conservation policies
favouring environmental heterogeneity are implemented, and that local inhabitants participate in the development of management
plans. 相似文献
16.
Floristic composition and diversity of mixed primary and secondary forests in northwest Guyana 总被引:3,自引:3,他引:0
Tinde van Andel 《Biodiversity and Conservation》2001,10(10):1645-1682
The adequate protection and sustainable management of a tropical rain forest requires a good knowledge of its biodiversity. Although considerable parts of Guyana's North-West District have been allocated as logging concessions, little has been published on the forest types present in this region. The present paper reviews the floristic composition, vegetation structure, and diversity of well-drained mixed and secondary forests in northwest Guyana. Trees, shrubs, lianas, herbs and hemi-epiphytes were inventoried in four hectare plots: two in primary forests, one in a 20-year-old secondary forest and one in a 60-year-old secondary forest. The primary forests largely corresponded with the Eschweilera–Licania association described by Fanshawe, although there were substantial variations in the floristic composition and densities of dominant species. The late-succession forest contained the highest number species and was not yet dominated by Lecythidaceae and Chrysobalanaceae. There is a need for updating the existing vegetation maps of northwest Guyana, as they were based on limited information. Large-scale forest inventories may provide a fair indication of species dominance and forest composition, but do not give a reliable insight in floristic diversity. Although previous reports predicted a general low diversity for the North-West District, the forests plots of this research were among the most diverse studied in Guyana so far. These results will hopefully influence the planning of protected areas in Guyana. 相似文献
17.
18.
East African coastal forests possess considerable botanical importance as an area of high plant endemicity, but are little known ecologically. Quantitative botanical sampling techniques have been used to determine vegetation communities in Pande and Kiono coastal forests, Tanzania. Data from 76 quadrats established in six transects (three in each forest) and containing a total of 146 plant species have been classified using TWINSPAN. Seven species-associations and four sample-associations are recognised. Undisturbed forest supports six species-associations which are rich in plant species of restricted distribution, and these differ between the sites studied. Forest heavily disturbed by man supports one species-association composed of more generalist forest species and this association is similar between sites. Variation in vegetation types of undisturbed forests appears to be caused by edaphic conditions, rainfall and degree of exposure. Variation in the vegetation of disturbed forests appears to be controlled by the intensity of forest disturbance. Heavy human disturbance of coastal forests reduces their biodiversity values as plant-diversity and the habitats of rare plant species are lost. 相似文献
19.
Louis Zapfack Stefan Engwald Bonaventure Sonke Gaston Achoundong Birang A Madong 《Biodiversity and Conservation》2002,11(11):2047-2061
Floristic surveys were carried out in different land use systems(primary and secondary forest, fallows of different ages, cocoa plantations,crop fields) within the forest zone of Cameroon, to assess the impact of landconversion on above-ground plant biodiversity. Beside various diversity studies,plant density was measured and diameter at breast height was estimated.The results showed that the forest areas, which represent thehistoric biodiversity of the region, preserve the greatest number of species(160 species in primary forest and 171 in secondary forest). Our resultsindicate the relatively great importance of secondary forests as refuge areasfor primary forest plant species that may function as a starting point forpossible regeneration of original biodiversity. Species richness is reducedprogressively from the original forest (160 spp.) and secondary forests (171spp.), to Chromolaena odorata (Asteraceae) fallow fields(149 spp.), to an old fallow field (139 spp.), to a cocoa plantation (116 spp.)and to the farmland (64 spp.), where only weeds and crops contribute essentiallyto plant biodiversity. Also the number of species that are used for non-timberproducts (construction, food and medicines) decreased with increased landconversion. 相似文献
20.
Julieta Benitez‐Malvido 《Biotropica》2006,38(2):171-182
I assessed the role of low vegetation (plants ca 1 yr old and ≤50 cm tall) as a biotic facilitator or barrier in the recruitment of different growth forms and species in primary forests, secondary forests, and old‐fields (abandoned pastures) in southeastern Mexico. I removed by hand all plants (≤100 cm tall, including roots) and litter from 20, 0.25 m2 plots in each habitat. For 1 yr, I counted the number of plant species (5–50 cm tall) recruited, grouped them into different growth forms, and compared them to undisturbed control plots. Prior to manipulation, the standing density of trees and lianas was highest in primary and secondary forests. Shrubs were more abundant in secondary forests, whereas herbs, epiphytes, and hemi‐epiphytes were more abundant in old‐fields. Herbaceous plants appeared as important components of the community in all habitats. The removal of low vegetation increased total plant recruitment in all habitats. Considering each growth form, the absence of vegetation increased recruitment in primary forests for herbs, in secondary forests for epiphytes and hemi‐epiphytes, in old‐fields for trees, and for lianas in primary forests and old‐fields. In vegetation removal plots, recruitment of species was greater in pastures, lower in secondary forest, and similar in primary forest with respect to control plots. Depending on habitat type, species, and growth form, the presence of low vegetation may act as a recruitment barrier or facilitator for different species, affecting plant community structure, diversity, and composition in different habitats. 相似文献