广东南岭大东山浙江润楠群落物种多样性与区系地理成分分析

应用植被调查样地法研究了广东南岭国家级自然保护区大东山片区的浙江润楠群落的物种多样性、区系地理成分,以及优势种种群的年龄结构。结果表明：（1）在1600m2的样地内共有维管束植物73科119属169种,群落的数量优势科为樟科、蔷薇科、山茶科、壳斗科及杜鹃花科等,种类组成的科、属地理成分中热带成分分别占74·51%和70·10%,温带成分分别占23·53%和33·64%;（2）该群落浙江润楠种群以幼、中龄树为主,其优势地位明显且稳定,乔木层的亚优势树种以罗浮栲、马尾松及荷木等为主;（3）群落垂直结构分为乔木层、灌木层和草本层3层,灌木层的物种最丰富,对群落物种多样性分析发现,Simpson指数：灌木层（乔木层=草本层,Shannon指数：灌木层（乔木层（草本层,Margalef指数：灌木层（乔木层（草本层,Pielou指数：乔木层（灌木层（草本层。     

四川大巴山巴山水青冈群落的物种多样性特征

巴山水青冈(Fagus pashanica)是川、陕、鄂、渝四省市交界处的特有植物。巴山水青冈林集中分布在四川省东北部的大巴山区。目前关于巴山水青冈群落的资料极其匮乏。作者在大巴山区通过对7个样地39个样方调查数据的分析, 探讨了巴山水青冈群落的物种多样性特征。主要结果有: (1) 巴山水青冈群落物种组成丰富, 共记录到维管束植物77科142属217种。乔木层物种集中于壳斗科、杜鹃花科、蔷薇科、山矾科等科; 灌木层物种集中于蔷薇科、忍冬科、壳斗科、槭树科等科; 草本层植物个体数量以苔草属(Carex)植物和普通鹿蹄草(Pyrola decorata)占绝对优势。(2) 群落乔木层物种多度对数呈倒“J”型分布, 灌木层与草本层的物种多度近似对数正态分布。群落物种丰富度由大到小依次为灌木层>草本层>乔木层; Shannon指数与Simpson指数的顺序为灌木层>乔木层>草本层; 均匀度指数的顺序为乔木层>灌木层>草本层。(3) 东坡、南坡的植物物种多样性高于北坡。乔木层Shannon指数与土壤第二层厚度回归关系显著; 草本层Shannon指数与土壤第一层厚度的回归关系显著; 灌木层的物种数和Shannon指数与土壤第一层有机质回归关系显著。(4) 群落建群种和乔木层主要树种重要值与物种多样性主要表现为负相关关系, 但与灌木层的物种多样性关系不显著(P≥0.05)。结果表明, 灌木层物种多样性主要受到环境因素的影响, 而乔木层和草本层物种多样性受到环境因子和群落自身特征的双重影响。     

大别山五针松群落物种多样性及区系分析

设置22个20m×20m的样地,对大别山五针松群落的物种多样性和区系成分进行了研究。结果显示,8800m²的样地内共有维管植物71科152属209种。其中,蕨类植物4科5属6种,裸子植物3科3属4种,被子植物64科144属199种。蔷薇科、樟科、菊科、杜鹃花科、豆科和禾本科等为优势科,所含物种较多。分析结果表明,大别山五针松群落种子植物区系起源古老,地理成分复杂,67个科中,世界分布、热带和温带分布的科分别有21、31和15个,显示出由热带向温带过渡的特性。147个属中,热带成分共43属,占总属数（不包括15个世界广布属）的32.58%;温带成分共有89属,占总属数的67.42%,并以北温带为主。群落垂直结构分为乔木层、灌木层和草本层,其中,Margalef指数、Simpson和Shannon-Wiener指数均以灌木层最大,其次为乔木层,草本层最低。灌木层与草本层的Pielou指数相近,且均大于乔木层。     

衡山青冈栎群落结构及物种多样性研究

利用样方法进行野外群落调查,共设计了15个样方,每个样方大小为20m×5 m,对衡山青冈栎(Cyclobalanopsis glauca)群落的种类组成、外貌、结构特征及物种多样性进行了研究.结果表明:在1 500 m2样地中,共有维管束植物26科37属46种,其中优势科为壳斗科、山茶科和蔷薇科等;该群落主要是以青冈栎为主的单优种群落,生活型谱以高位芽植物占绝对优势,叶级谱以中、小型叶为优势的特点,群落季相不明显;群落分层较明显,乔木层树种很少,灌木层种类较丰富,对群落物种多样性具有较大影响;物种多样性分析显示该群落多样性指数偏低,其多样性复杂程度由高到低的顺序为灌木层、藤本层、乔木层、草本层.     

井冈山自然保护区福建柏群落的研究

对井冈山福建柏(Fokienia hodginsii)群落4个样地的物种组成、区系成分和物种多样性进行了统计和分析.结果表明:该群落有维管植物32科43属59种,其中蕨类植物有4科4属5种,裸子植物3科3属3种,被子植物25科36属51种.区系分析显示该植物区系起源古老,地理成分复杂,以温带性成分为主,热带亚热带成分占有较大比例.群落为复层异龄结构,类型有福建柏 甜槠(Castanopsis eyrei)群落、福建柏 猴头杜鹃(Rhododendronsimiarum) 甜槠群落.群落物种多样性指数较高,各样地间多样性指数变幅不大;福建柏群落的4种多样性指数基本表现出相同的趋势,福建柏群落物种多样性在群落不同层次的变化规律为:灌木层>乔木层>草本层.     

格氏栲自然保护区常绿阔叶林植物组成特征分析

本文在11000m²样地调查材料的基础上,分析了福建三明格氏栲自然保护区常绿阔叶林群落的植物种类组成、分布区类型和物种多样性特点。结果显示,群落共计有维管植物223种,隶属于80个科159属,其中单种属占总属数的80.5%;地理成分复杂,具有中国15个种子植物属分布区类型中的12个,且以热带亚热带成分为主,其中泛热带分布属的比例最高,其次为热带亚洲分布属,温带成分占有一定比例;群落不同层次多样性指数由大到小的变化规律为:灌木层 >乔木层 >草本层;植物分布区类型与物种多样性指数的分析表明,该群落是介于南亚热带季风常绿阔叶林和中亚热带常绿阔叶林之间的过渡类型。     

赤水桫椤国家级自然保护区桫椤群落特征及物种多样性研究

桫椤(Alsophila spinulosa),为中生代古老孑遗物种,国家二级保护植物。贵州赤水桫椤国家级自然保护区是以桫椤及其生存环境为保护对象的自然保护区,是拥有世界上数量最多、面积最广的桫椤林区之一。该文采用植物生态学、区系学等方法,对保护区内群落及物种多样性、伴生物种区系成分、生活型谱、群落结构等进行研究。结果表明:(1)群落内维管植物共计60科96属122种,其中蕨类植物12科14属17种,裸子植物2科2属2种,被子植物46科80属103种。(2)群落内植物的科、属区系成分类型多样,热带成分占优势,温带成分次之,表现出从热带区系向温带区系过渡的特征。(3)生活型谱以高位芽植物为主(占57.38%),反映出中亚热带森林以高位芽植物为优势的特点。(4)群落垂直分层显著,乔木层树高在4~12m的比例最大为76.64%;灌木层树高在2~3m的比例最大为69.78%;草本层各区间分布较为均匀,但以0~0.2 m的比例较大,群落层次明显。(5)毛竹(Phyllostachys heterocycla cv.pubescens)和桫椤在该地乔木组成中占主导地位;灌木层中,桫椤为最优物种;草本层主要以红盖鳞毛蕨(Dryopteris erythrosora)、翠云草(Selaginella uncinata)为主;物种丰富度分析显示,乔木层灌木层草本层;多样性指数、均匀度指数分析表明,乔木层为聚集分布、组成较简单,灌木层和草本层为均匀分布,但数量较少。     

青海省高寒灌丛物种多样性、生物量及其关系

物种多样性对生态系统功能的作用是生物多样性研究的核心领域之一,生物量水平是生态系统功能的重要表现形式,而植物群落的生物量则是生态系统生物量的基础,因此研究植物群落物种多样性与生物量的关系,对于阐明植物多样性对生态系统功能的作用具有重要意义。通过对青海省高寒灌丛生物量、灌丛物种多样性特征以及与生物量的关系调查,得到以下结果:(1)被调查灌木植被群落的40个样地中共出现了207种植物(其中灌木植物18种,草本植物189种),隶属于130属,43科,灌木以蔷薇科、杜鹃花科为主,而草本以菊科、龙胆科、毛茛科和莎草科占优势。(2)群落多样性指数偏低,植物群落结构简单,物种组成稀少。小叶金露梅群落的多样性指数最大,金露梅群落、细枝绣线菊群落和鲜卑花群落次之,百里香杜鹃+头花杜鹃群落最低。(3)不同高寒灌丛类型生物量介于1893.03—7585.41 g/m~2之间,平均值为3775.9 g/m2,其中灌木生物量占灌丛总生物量的73.55%,草本为26.45%。(4)总生物量随草本物种多样性和群落物种多样性的增加而减小;草本生物量随其物种多样性的增加而减小,而灌木物种多样性与其生物量并无显著相关性。     

广东南岭国家级自然保护区疏齿木荷+福建柏群落结构与物种多样性研究

通过样方调查,对广东南岭国家级自然保护区秤架管理站辖区内海拔1 400 m左右的疏齿木荷(Schimaremotiserrata)+福建柏(Fokienia hodginsii)落的物种组成、群落结构和物种多样性进行分析.结果表明,在1 600 m~2的样地内共有维管束植物45科75属113种,以泛热带成分为主,热带和温带成分也有一定的比例,表现出较为明显的过渡性质;群落组成以疏齿木荷、福建柏和青茶冬青(Ilex hanceana)等为主,成分复杂,类型多样,优势种优势地位分散而不明显;群落分为乔木层、灌木层和草本.藤本层3层,层间植物稀少,生活型以常绿小、中高位芽植物为主,分别占30.97%和27.43%;按Raunkiaer标准,群落内的种群频度为1%～20%的种类占优势,为总种数的55.75%,福建柏种群以低龄幼树为主,呈增长状态;丰富度指数、Shannon-Wiener指数、Sknpson指数和均匀度指数等均表现出相同的趋势,为灌木层>乔木层>草本.藤本层.     

草海国家级自然保护区华山松群落特征及物种多样性研究

为探讨喀斯特地区森林群落的演替动态和生物多样性维持机制,采用样地调查法对草海国家级自然保护区的华山松(Pinusarmandii)群落的物种组成、植物区系特征、种群结构和物种多样性等进行了分析。结果表明,样地内共有种子植物37科69属81种,其中乔木11种、灌木32种、草本38种;群落内植物的科、属区系成分类型多样,以温带成分为主;生活型谱主要以高位芽植物(46.91%)和地面芽植物(27.16%)为主;乔木层华山松的重要值达58%,为群落的单优势种;径级结构呈左偏正态型分布,树高分布集中在12～21 m,冠幅分布呈V型;乔木层与灌木层、草本层间的多样性差异显著(P0.05),物种丰富度指数S和D_M、多样性指数H和D_S均为草本层灌木层乔木层,物种均匀度指数J为灌木层草本层乔木层。因此,草海国家级自然保护区内的华山松群落特征和物种多样性具有明显的地域特点。     

中国南部亚热带森林地表植被动态变化

系统研究了南方5个亚热带森林生态系统地表植被的动态变化情况.研究方法是:在每个研究区域内,按照地形梯度分别布设50个1m2 的样方,记录样方内所有物种的频度及相关的环境变量,5个研究区域共设250个样方,每个样方分别调查两次.通过单元及多元统计方法分析表明:维管植物物种频度在一个区域明显下降,另二个区域显著增加;苔藓物种频度在一个区域有明显下降,另一个区域明显增加;苔藓物种数量在3个区域显著增加,另二个区域显著下降;维管植物物种数量显著增加在二个区域;物种组成沿着第一个植被梯度轴DCA 1没有显著变化,沿着第二个植被梯度轴DCA 2在二个区域有显著变化.综合分析表明,苔藓对气候变化及其波动反映敏感,是较好的气候变化及气候波动生物指示因子,而管植物数量及频度的变化没有明显证据显示与土壤酸化和大气污染有紧密关系.     

Land use history, hurricane disturbance, and the fate of introduced species in a subtropical wet forest in Puerto Rico

Tropical forests are suffering from increasing intensities and frequency of disturbances. As a result, non-native species accidentally introduced or intentionally planted for farming, plantations, and ornamental purposes may spread and potentially invade undisturbed native forest. It is not known if these introduced species will become invasive, as a result of recurrent natural disturbances such as hurricanes. Using data from three censuses (spanning 15 years) of a 16-ha subtropical wet forest plot, we investigated the impact of two hurricanes on populations of plant species that were planted in farms and plantations that were then abandoned and from the natural spread of species introduced into Puerto Rico in the past. The populations of four species (Citrus paradis, Mangifera indica, Musa sp., and Simarouba glauca) changed little over time. Six species (Artocarpus altilis, Calophyllum calaba, Genipa americana, Hibiscus pernambucensis, Syzygium jambos, and Swietenia macrophylla) declined between the first two censuses after Hurricane Hugo, then increased again in Census 3 after Hurricane Georges. Spathodea campanulata gradually increased from census to census, while Coffea arabica declined. These introduced species represent only a small part of the forest basal area and few show signs of increasing over time. The number of stems per plant, new recruits, and the growth rates of these introduced species were within the ranges of those for native plant species. The mortality rates over both census intervals were significantly lower for introduced species (<5% year⁻¹) than for native ones (15% year⁻¹). Many new recruits established after Hurricane Hugo (prior to this study) had opened the forest canopy and these high mortality rates reflect their death as the canopy recovered. Only Swietenia macrophylla and Syzygium jambos showed an increase in stem numbers in the closed canopy area of forest that had suffered limited human disturbance in the past. A future increase in frequency of disturbance may enable greater stem numbers of introduced species to establish, while lower-mortality rates compared to native species, may allow them to persist during inter-hurricane intervals. An increase in the population of introduced species, especially for those that grow into large trees, may have an impact on this tropical forest in the future.     

Detection of a colonizing, aquatic, non-indigenous species

Detecting the presence of rare species has interested ecologists and conservation biologists for many years. A particularly daunting application of this problem pertains to the detection of non-indigenous species (NIS) as they colonize new ecosystems. Ethical issues prevent experimental additions of NIS to most natural systems to explore the relationship between sampling intensity and the detection probability of a colonizing NIS. Here we examine this question using a recently introduced water flea, Cercopagis pengoi , in Lake Ontario. The species has biphasic population development, with sexually-produced 'spring morphs' developing prior to parthenogenetically-produced 'typical' morphs. Thus, this biphasic morphology allows distinction between new colonists (spring morphs) from subsequent generations. We repeatedly sampled Hamilton Harbour, Lake Ontario for the presence of both spring and typical morphs. Probability of detection was positively related to both the number of samples taken and animal density in the lake; however, even highly intensive sampling (100 samples) failed to detect the species in early spring when densities were very low. Spatial variation was greatest when densities of Cercopagis were intermediate to low. Sub-sampling, which increased space between adjacent samples, significantly decreased the number of samples required to reach greater, calculated detection probabilities on these dates. Typical sampling protocols for zooplankton have a low probability (< 0.2) of detecting the species unless population density is high. Results of this study suggest that early detection of colonizing, aquatic NIS may be optimized through use of a risk-based sampling design, combined with high sampling intensity in areas deemed most vulnerable to invasion, rather than less intensive sampling at a wider array of sites.     

Human land use, agriculture, pesticides and losses of imperiled species

Aim  Anthropogenic habitat loss is usually cited as the most important cause of recent species' extinctions. We ask whether species losses are in fact more closely related to habitat loss than to any other aspect of human activity such as use of agricultural pesticides, or human population density (which reflects urbanization).
Location  Canada.
Methods  We statistically compared areas in Canada where imperiled species currently occur, versus areas where they have been lost. Using multiple regressions, we relate the numbers of species that had suffered range reductions in an ecoregion to variables that represent present habitat loss, pesticide use and human population density.
Results  We find high losses of imperiled species in regions with high proportions of agricultural land cover. However, losses of imperiled species are significantly more strongly related to the proportion of the region treated with agricultural pesticides. The relationship between species losses and area treated with pesticides remains significant after controlling for area in agriculture.
Main conclusions  Our results are consistent with the hypothesis that agricultural pesticide use, or something strongly collinear with it (perhaps intensive agriculture more generally), has contributed significantly to the decline of imperiled species in Canada. Habitat conversion per se may be a less important cause of species declines than how that converted habitat is used.     

Assessment of the seaweed-seagrass resource of Mararison Island,Culasi, Antique,Philippines*

A bimonthly sampling of the seaweed-seagrass resource of Mararison Island, Culasi Antique, was undertaken over 1 year to assess the species composition, similarity of taxa, and biomass (dry weight [d.w.] g m^?2) at seven localities. A total of 45 species was identified: 17 Chlorophyta, seven Phaeophyta, 15 Rhodophyta, one Cyanophyta and five seagrasses. Except for some Rhodophyta and Syringodium isoetifolium (Ascherson) Dandy, the occurrence of species between stations was not significantly different; however, differences in biomass between sampling time (month) were significant. Identical taxa between stations were determined. The highest (40) and lowest (22) number of species collected were in May and July, respectively. The species were most abundant from March to May (dry months) and sparse from July to September (wet months). The most abundant species were: Sargassum polycystum C. Agardh (399 g m^?2) (Phaeophyta), Dictyosphaeria cav-ernosa (Forsskat) Borgesen (43.1 g m^?2) (Chlorophyta), Acanthopeitis japonica Okamura (97.2 gm^?2) (Rhodophyta) and Thalassia hemprichii (Ehrenberg) Ascherson (1370 g m^?2; seagrass). The Phaeophyta were abundant in March, and the Chlorophyta and Rhodophyta in May, while the seagrasses were abundant in September. Some species occurred only during the dry months: two Phaeophyta, nine Chlorophyta and five Rhodophyta. All the seagrasses were found year-round. Almost all of the seaweeds (39/45) were found associated with seagrass. The number of seaweeds in Mararison Island was higher than for seagrasses but the total biomass of the latter was much higher than the combined biomass of the seaweeds.     

Increasing numbers of bird species result from taxonomic progress,not taxonomic inflation

The impact and significance of modern taxonomy on other fields in biology have been subjects of much debate. It has been proposed that increasing numbers of vertebrate species are largely owing to ‘taxonomic inflation’. According to this hypothesis, newly recognized species result from reinterpretations of species limits based on phylogenetic species concepts (PSCs) rather than from new discoveries. Here, I examine 747 proposals to change the taxonomic rank of birds in the period 1950–2007. The trend to recognize more species of birds started at least two decades before the introduction of PSCs. Most (84.6%) newly recognized species were supported by new taxonomic data. Proposals to recognize more species resulted from application of all six major taxonomic criteria. Many newly recognized species (63.4%) were not based exclusively on PSC-based criteria (diagnosability, monophyly and exclusive coalescence of gene trees). Therefore, this study finds no empirical support for the idea that the increase in species is primarily epistemological rather than data-driven. This study shows that previous claims about the causes and effects of taxonomic inflation lack empirical support. I argue that a more appropriate term for the increase in species is ‘taxonomic progress’.     

Influence of settlement time, human population, park shape and age, visitation and roads on the number of alien plant species in protected areas in the USA

Abstract. I examined a data set of 77 protected areas in the USA (including national and state parks) to determine which of the following variables most strongly influence alien plant species richness: park area, climate (temperature and precipitation), native species richness, visitation rate, local human population size, total road length, park shape and duration of European settlement. Many of these predictor variables are intercorrelated, so I used multiple regression to help separate their effects. In support of previous studies, native species richness was the best single predictor of alien species richness, probably because it was a good estimator of both park area and habitat diversity available for establishment of alien species. Other significant predictors of alien species richness were years of occupation of the area by European settlers and the human population size of adjacent counties. Climate, visitation rate, road length and park shape did not influence alien species richness. The proportion of alien species (alien richness/native richness) is inversely related to park area, in agreement with a previous study. By identifying which variables are most important in determining alien species richness, such findings suggest ways to reduce alien species establishment.     

云南西双版纳的淡水蟹类 (软甲纲:十足目:束腹蟹科:溪蟹科)

本文记述西双版纳６种淡水蟹类的种类组成及分布,其中包括二新种的描述。     

贵州兴义实蝇类昆虫多样性特征

【目的】掌握贵州兴义实蝇的种类组成和不同生境中的发生规律及多样性变化。【方法】2010-2011年,在贵州兴义 5个不同生境的监测点,采用性诱剂、食物引诱剂及被害瓜果培养法对实蝇类昆虫种类和数量进行了系统调查和监测,并对监测数据进行分析。【结果】贵州兴义实蝇优势种包括桔小实蝇 Bactrocera dorsalis (Hendel)、瓜实蝇 B. cucurbitae (Coquillett)、南瓜实蝇 B. tau (Walker)及具条实蝇 B. scutellata (Hendel),且不同年份各监测点实蝇优势种及相似性系数(0.33~0.89)存在差异;但其年种群动态相似。聚类分析结果显示,两个农村生境果园中实蝇种群关系最近,城市混合果园与其他生境果园中实蝇种群关系最远;各监测点的多样性指数在不同年份也不同,监测的2年间 Simpson 指数、Shannon 指数和均匀度指数分别在0.11~0.68、0.28~1.25和0.18~0.62之间。【结论】贵州兴义实蝇种类丰富,种群发生规律与气候、寄主、生态位竞争等因素有关;相近生境混合果园诱捕到的实蝇种数和数量大于单一果园;离城区越近,实蝇发生期越早,数量越大。研究结果为了解该地区实蝇种类分布以及预防实蝇危害提供了科学依据。     

指示种、伞护种与旗舰种:有关概念及其在保护生物学中的应用

指示种、伞护种和旗舰种等的运用常常可以作为解决保护生物学问题的捷径。指示种被用来评价环境中人为干扰因素的程度,监测其他物种的种群动态,或用于确定生物多样性较高的区域;伞护种则常用来确定需保护生境的类型和面积;而旗舰种被用于引起公众对保护行为的关注。本文试图对上述术语和概念在使用上加以明确区分,并对其应用提出一些指导性原则。认为针对上述不同类型的代理种,使用的目的和选择的标准应有所不同,彼此不能混淆使用。