Bryophytes and lichens in 16th-century herbaria

The diversity of bryophyte and lichen collections in 9 of the oldest preserved herbaria (dating from ca 1542 to 1577) was compared, including the first reports of bryophytes and lichens from the ‘En Tibi’ herbarium (possibly 1542–1544) and the herbarium of Leonhard Rauwolf (1560–1563). Bryophytes and lichens formed only a minority in each herbarium compared to the numbers of vascular plant specimens; numbers ranged from representatives of 21 genera in the herbarium of Ulisse Aldrovandi to the single genus Conocephalum in the Rauwolf herbarium. The focus was on large, handsome species of bryophytes and macrolichens, apart from small amounts of additional species collected as ‘by-catch’ in mixed collections. All herbaria together included 34 genera of bryophytes (36 species and 10 specimens identified to genus level) and 13 genera of lichens (24 species and 4 specimens identified to genus level). The diversity of mosses was higher than that of liverworts, and pleurocarpous mosses were more diverse than acrocarpous mosses. The collectors probably aimed at selecting material that was either characteristic of the vegetation in the respective areas of collecting or used for certain purposes (or both). The former hypothesis is supported by the small overlap in taxonomic diversity between the herbaria, and the latter by the fact that several moss, liverwort, and lichen genera are included whose traditional uses are well documented.     

Chilean Bromeliaceae: diversity, distribution and evaluation of conservation status

Chile is home to 23 species of Bromeliaceae, including 2 subspecies and 4 varieties. Twenty species are endemic to the country. We examined 883 herbarium specimens from 27 herbaria for our treatment of the Bromeliaceae for the “Flora de Chile”. These data and field observations resulted in a comprehensive database that we used to generate distribution maps for each species. We applied ecological niche modelling to reveal distribution areas and centers of Bromeliaceae diversity. We further analysed the collecting dates of the herbarium specimens to assess possible changes in species abundance. In this study we assess the conservation status of the bromeliad species in Chile. IUCN categories were assigned to the 27 bromeliad taxa as follows: Critically endangered: 4, Endangered: 6, Vulnerable: 11, Near threatened: 2, Least concern: 4. No species has become “Extinct” up to now. We also put forth a hypothesis about their biogeographic history.     

Ecogeographic survey of the genus Coffea in the Mascarene Islands

An ecogeographic survey is required for the development of a strategy for the conservation and use of plant genetic resources. An herbarium-based ecogeographic survey is presented, supplemented by detailed field surveys of wild Coffea species in the Mascarene Islands. The geographical and ecological distribution of the different Coffea species in the Mascarene Islands, principally in Mauritius, is determined, and an assessment is made of the IUCN conservation status of native Coffea species. Ecogeographic data were collated from herbarium specimens from four major herbaria holding collections of Mascarene Coffea . The geography, ecology, phenology and conservation status of the Coffea species from Mauritius are discussed.     

Sources of information about botanic gardens and herbaria

Botany is the study of living plants in the garden and the wild and of dead plants in the herbarium and laboratory. The value of a botanic garden for teaching purposes became evident in the 16th century with the founding between 1543 and 1600 of botanic gardens at Pisa, Padua, Florence, Bologna, Leyden, Leipzig, Paris, Montpellier and Heidelberg: indeed most of the major European botanic gardens were founded during this and the next two centuries. Associated with the study of living plants in botanic gardens was the invention of the herbarium by Luca Ghini (1490–1556) and the subsequent making of many private herbaria, out of which have developed the large institutional herbaria, mostly in the 18th and 19th centuries. The continuous enrichment of European gardens by the introduction of new plants resulting from European exploration and colonization created many problems of classification and naming, and so led to the development of taxonomic methods and the adoption of consistent binomial nomenclature for species, following Linnaeus, during the 18th century. The fashion for collecting in the 17th and 18th centuries resulted in the amassing of big private collections which later became the basis of institutional collections. The increase of such public collections by making available material for study from all over the world has, in turn, increased the publications relating to this. Thus the botanic garden and the herbarium, with their associated libraries, have become complementary repositories of botanical information invaluable to the taxonomist, the plant geographer, the economic botanist and the student of evolution. Some useful publications relating to botanic gardens, herbaria and botanical and horticultural collectors are listed.     

The contribution of small collections to species distribution modelling: A case study from Fuireneae (Cyperaceae)

The recent and rapid digitization of biodiversity data from natural history collection (NHC) archives has enriched collections based data repositories; this data continues to inform studies of species' geographic distributions. Here we investigate the relative impact of plant data from small natural history collections (collections with < 100,000 specimens) on species distributional models in an effort to document the potential of data from small NHCs to contribute to and inform biodiversity research. We modelled suitable habitat of five test case species from Fuireneae (Cyperaceae) in the United States using specimen records available via the Global Biodiversity Information Facility and that of data ready to mobilize from two regional small herbaria. Data were partitioned into three datasets based on their source: 1) collections-based records from large NHCs accessed GBIF, 2) collections-based records from small NHCs accessed from GBIF, and 3) collections-based records from two small regional herbaria not yet mobilized to GBIF. We extracted and evaluated the ecological niche represented for each of the three datasets by applying dataset occurrences to 14 environmental factors, and we modelled habitat suitability using Maxent to compare the represented distribution of the environmental values among the datasets. Our analyses indicate that the data from small NHCs contributed unique information in both geographic and environmental space. When data from small collections were combined with data from large collections, species models of the ecological niche resulted in more refined predictions of habitat suitability, indicating that small collections can contribute unique occurrence data which enhance species distribution models by bridging geographic collection gaps and shifting modelled predictions of suitable habitat. Inclusion of specimen records from small collections in ongoing digitization efforts is essential for generating informed models of a species' niche and distribution.     

Biological collections in an ever changing world: Herbaria as tools for biogeographical and environmental studies

Plant specimens stored in herbaria are being used as never before to document the impacts of global change on humans and nature. However, published statistics on the use of biological collections are rare, and ecologists lack quantitative data demonstrating the relevance to science of herbarium specimens. I found 382 studies with original data that used herbarium specimens to document biogeographical patterns or environmental changes. Most studies are less than 10 years old, and only 1.4% of the herbarium specimens worldwide have been used to answer biogeographical or environmental questions. The vast majority (82%) of papers dealt with vascular plants, but some studies also used bryophytes, lichens, seaweeds and fungi. The herbarium specimens were collected from all continents, but most of the studies used specimens from North America (40% of studies) or Europe (28%). Many types of researches (conservation, plant disease, plant invasion, pollution, etc.) can be conducted using herbarium specimens. Climate change, and especially phenological reconstructions, are clearly emerging research topics. By group, small herbaria (<100,000 specimens) are consulted as often as very large herbaria (>1,000,000 specimens) for biogeographical and environmental research, but in most cases, only large facilities provide specimens collected worldwide. The median number of specimens per study in papers using computerized collections (15,295) was much higher than for papers that did not include electronic data (226). The use of molecular analyses to investigate herbarium specimens is still relatively unexplored, at least from biogeographical and environmental points of view. Combined with recently developed procedures to correct biases, herbarium specimens might provide in the near future exciting additional spatio-temporal insights that are currently unimaginable.     

Assessing the Relevance of Herbarium Collections as Tools for Conservation Biology

Herbarium collections constitute permanent and often well-documented records of the distribution of taxa through space and time. Since their creation, their uses have dramatically expanded and with many new uses being proposed, including some for which herbaria were not initially intended for. In this paper we assess the potential of these collections on conservation biology, by providing exemplary studies that use herbarium specimens, grouped into four categories: (1) based on occurrence data, such as studies about plant extinction or introduction, or those focused on modelling their ecological niche; (2) based on the specimens themselves, such as morphological or phenological studies to evaluate the impact of climate change; (3) based in genetic data, such as phylogeographic or taxonomical studies; and (4), other applied studies.     

Predicting species distributions from herbarium collections: does climate bias in collection sampling influence model outcomes?

Aim Species distribution models and geographical information system (GIS) technologies are becoming increasingly important tools in conservation planning and decision‐making. Often the rich data bases of museums and herbaria serve as the primary data for predicting species distributions. Yet key assumptions about the primary data often are untested, and violation of such assumptions may have consequences for model predictions. For example, users of primary data assume that sampling has been random with respect to geography and environmental gradients. Here we evaluate the assumption that plant voucher specimens adequately sample the climatic gradient and test whether violation of this assumption influences model predictions. Location Bolivia and Ecuador. Methods Using 323,711 georeferenced herbarium collections and nine climatic variables, we predicted the distribution of 76 plant species using maximum entropy models (MAXENT) with training points that sampled the climate environments randomly and training points that reflected the climate bias in the herbarium collections. To estimate the distribution of species, MAXENT finds the distribution of maximum entropy (i.e. closest to uniform) subject to the constraint that the expected value for each environmental variable under the estimated distribution matches its empirical average. The experimental design included species that differed in geographical range and elevation; all species were modelled with 20 and 100 training points. We examined the influence of the number of training points and climate bias in training points, elevation and range size on model performance using analysis of variance models. Results We found that significant parts of the climatic gradient were poorly represented in herbarium collections for both countries. For the most part, existing climatic bias in collections did not greatly affect distribution predictions when compared with an unbiased data set. Although the effects of climate bias on prediction accuracy were found to be greater where geographical ranges were characterized by high spatial variation in the degree of climate bias (i.e. ranges where the bias of the various climates sampled by collections deviated considerably from the mean bias), the greatest influence on model performance was the number of presence points used to train the model. Main conclusions These results demonstrate that predictions of species distributions can be quite good despite existing climatic biases in primary data found in natural history collections, if a sufficiently large number of training points is available. Because of consistent overprediction of models, these results also confirm the importance of validating models with independent data or expert opinion. Failure to include independent model validation, especially in cases where training points are limited, may potentially lead to grave errors in conservation decision‐making and planning.     

A review and typification of some of Kunze's newly described South African Pteridophyta published in his Acotyledonearum Africae Australioris Recensio Nova

A brief historical background is provided concerning some early collectors and their pteridophyte collections in South Africa which preceded the publication of Kunze's Acotyledonearum Africae Australioris Recensio Nova , a paper which was largely based on the pteridophyta collection of Drege, Ecklon and Zeyher. This paper was reprinted twice during 1836. Inconsistencies led to a great deal of confusion. Kunze recognized a total of 123 species (a figure which excluded forms and varieties), and of these 29 were described for the first time. The destruction of Kunze's herbarium resulted in most of his species which are described here, and elsewhere, remaining untypified. A search in most of the prominent European herbaria has revealed that adequate duplicates still exist and most of the taxa described by Kunze in the relevant publication can now be typified.     

An elevational shift of cryophilous bryophytes in the last century – an effect of climate warming?

Aim To investigate altitudinal range shifts of bryophytes in Switzerland by comparing recent altitudinal distributions with historical distributions derived from herbarium specimens. Location Switzerland, covering 41,285 km² in Central Europe. Methods We used a dataset of 8520 herbarium specimens of 61 bryophyte species and compared altitudinal data between the two periods 1880–1920 and 1980–2005. The records we used were not specifically sampled for climatological analyses, but originate from non‐systematic fieldwork by various collectors. Historical and recent records were distributed all over Switzerland with occurrences in all major biogeographical areas. To account for different sampling efforts in the two time periods, different subsampling procedures were applied. Results Overall, we found a significant mean increase in altitude of 89 ± 29 m which was mainly driven by the cryophilous species (+222 ± 50 m). The mean increase in altitude of cryophilous species corresponds to a decadal upward shift of 24 m. The upper range limit of cryophilous species also increased by 189 ± 55 m, but there was no effect on the lower range limit. For intermediate and thermophilous species neither mean, nor upper or lower range limits changed. However, the proportion of records of thermophilous to cryophilous species increased considerably at lower altitudes, but levelled off above approximately 1800 m. Main conclusions We conclude that cryophilous bryophytes are expanding their range to higher elevations in Switzerland and that at lower elevations, a slow extinction process is going on, probably as a result of climate warming trends. The observed decadal upward shifts of cryophilous species closely match those reported from vascular plants in Europe and those expected, given recent estimates of climate warming trends. We emphasize that herbaria provide valuable data that can be used to detect ongoing changes in the distribution of species.     

Response of plant species and life form diversity to variable fire histories and biomass in the jarrah forest of south‐west Australia

Frequent fires reduce the abundance of woody plant species and favour herbaceous species. Plant species richness also tends to increase with decreasing vegetation biomass and cover due to reduced competition for light. We assessed the influence of variable fire histories and site biomass on the following diversity measures: woody and herbaceous species richness, overall species richness and evenness, and life form evenness (i.e. the relative abundance or dominance among six herbaceous and six woody plant life forms), across 16 mixed jarrah (Eucalyptus marginata) and marri (Corymbia calophylla) forest stands in south‐west Australia. Fire frequency was defined as the total number of fires over a 30‐year period. Overall species richness and species evenness did not vary with fire frequency or biomass. However, there were more herbaceous species (particularly rushes, geophytes and herbs) where there were fewer shrubs and low biomass, suggesting that more herbaceous species coexist where dominance by shrubs is low. Frequently burnt plots also had lower number and abundance of shrub species. Life form evenness was also higher at both high fire frequency and low biomass sites. These results suggest that the impact of fire frequency and biomass on vegetation composition is mediated by local interactions among different life forms rather than among individual species. Our results demonstrate that measuring the variation in the relative diversity of different woody and herbaceous life forms is crucial to understanding the compositional response of forests and other structurally complex vegetation communities to changes in disturbance regime such as increased fire frequency.     

中国高等植物数字化标本分析

传统上馆藏标本,主要用于植物分类学、植物资源学的研究。数字标本的出现将标本的使用拓展到从研究生物多样性时间空间分布到生态学和进化学理论、生物多样性保护、农业和人类健康等广泛领域。截至目前,从互联网上获取的采自中国的植物标本数量已有1 200多万份。该文通过整理和分析这些数据以了解中国植物标本的数字化精度、采集时间和采集地区规律以及采集空缺等状况。结果表明:中国标本采集形成了4个高峰,即20世纪30年代、60年代、80年代和21世纪初,中国植物标本采集和研究工作主要在20世纪50年代后由中国学者完成。标本采集地区覆盖度在省级较好,县级标本采集则很不平衡; 标本采集类群在科属层面覆盖率高,但近五分之一的物种采集不足; 标本的采集量既与植物分布幅度相关,也与采集地区的知名度、所获科研项目及采集者偏好有关。未来中国植物标本数字化方向应该在继续挖掘馆藏标本的同时,一方面开展对现有数字化标本信息再审核及补充,并加强与欧美大馆的信息共享以获取早期历史标本信息; 另一方面应用数字化标本信息分析结果,指导境内标本的精准采集,包括采集薄弱/空白地区、采集薄弱/空白属种的采集,以进一步增强实体标本馆能力,提高数字化标本质量,为进一步完善植物标本数字化和精准化采集提供依据,更好地服务科学和社会的发展。     

Mapping patterns of ferns species richness through the use of herbarium data

This paper aims to analyse the spatial patterns of sampling effort and species richness of pteridophyte in a well-investigated region as Tuscany, Italy, by using data stored from a geodatabase storing information on the specimens preserved in the main herbaria of the region. A total of 6,905 records about pteridophyte specimens were extracted from the geodatabase, and 5,638 of such specimens were studied through the use of spatial statistical techniques. The data about the sampling effort and species richness were analysed in relation to topographical variables to assess any significant relationship. Specimen-based rarefaction techniques were used to compare areas with different number of detected species. The analysis of the sampling effort data showed a nonhomogeneous distribution of herbarium data, with some areas being intensively sampled and others being almost unsampled. Thus, the geographical distribution of specimens was extremely clustered. The comparison across geographical areas through specimen-based rarefaction curves showed great differences in species richness and sampling completeness. The analysis of the residuals of species–area relationships evidenced that the distance to water bodies was the only significant topographical variable in controlling species diversity.     

Scale-dependent spatial patterns of species diversity in the tropical montane rain forest in Jianfengling,Hainan Island,China

Aims Spatial distribution patterns and formation mechanisms of species diversity are fundamental issues in community ecology. The objectives of this study are to assess the species diversity patterns at the different spatial scales in Jianfengling, Hainan Island, China.
Methods Based on the dataset from the 60 hm² plot in the tropical montane rain forest in Jianfengling, Hainan Island, the spatial distribution patterns of species richness, species abundance, Shannon-Wiener, Simpson and Pielou’s evenness indices were analyzed at six spatial scales, including 5 m × 5 m, 10 m × 10 m, 20 m × 20 m, 40 m × 40 m, 100 m × 100 m, and 200 m × 200 m, respectively.Important findings
Results showed that spatial distribution patterns of species richness, species abundance and Shannon-Wiener index were much more obviously changed with the spatial scales than Simpson and Pielou’s evenness indices. Change of variance of the species richness with the increase of spatial scales was unimodal, which had the maximum value at the 20 m × 20 m scale. Variance of the species abundance showed a linear relationship with the increase of spatial scales. The positive relationship between species richness and abundance gradually decreased and even disappeared with the increase of sampling scales, which may be correlated with the increase of habitat heterogeneity. The effects of spatial scales on Shannon-Wiener, Simpson, and Pielou’s evenness indices may be also correlated with the composition of rare species in the plot.     

海南尖峰岭热带山地雨林物种多样性空间分布格局的尺度效应

物种多样性的空间分布格局和维持机制是群落生态学的基本问题。为了探讨海南尖峰岭地区物种多样性空间分布格局的尺度效应, 以海南尖峰岭热带山地雨林60 hm²样地为研究对象, 分析了物种丰富度、物种多度、Shannon-Wiener指数、Simpson指数以及Pielou均匀度指数随6个空间取样尺度(5 m × 5 m、10 m × 10 m、20 m × 20 m、40 m × 40 m、100 m ×100 m、200 m × 200 m)的变化。结果表明: 相比Simpson指数和Pielou均匀度指数, 物种丰富度、多度以及Shannon-Wiener指数具有更为明显的空间尺度效应; 物种丰富度的方差随取样尺度增加呈现单峰分布特征, 并且在20 m × 20 m尺度上达到最大值, 而物种多度的方差随取样尺度的增加而增大; 物种丰富度和多度的正相关性随着取样尺度的增加逐渐减小甚至消失, 这可能与随取样尺度增加生境异质性增加有关; 取样尺度对3个物种多样性指数空间分布的影响可能与研究区域内稀有种的组成有关。     

Adaptive radiation of shrubby tarweeds (Deinandra) in the California Islands parallels diversification of the Hawaiian silversword alliance (Compositae-Madiinae)

Phylogenetic analyses of nuclear rDNA transcribed spacers and cytogenetic studies of interspecific hybrids reported here uphold Carlquist's hypothesis (1965, Island Biology) that shrubby tarweeds (Deinandra) of Guadalupe Island, Mexico, are products of in situ radiation in the California Islands, where evidence of plant diversification has been equivocal. Based on the rDNA findings, the Guadalupe Island endemics (D. frutescens, D. greeneana subsp. greeneana, and D. palmeri) constitute a clade that arose since the late Pliocene, well after the origin of Guadalupe Island and diversification of annual, mainland Californian lineages of Deinandra. High interfertility and normal meiosis in F(1) hybrids between the three endemics contrast with reduced interfertility (to complete intersterility) and meiotic irregularities in F(1) hybrids between other, mostly mainland species of Deinandra. Cloned rDNA sequences provided no convincing evidence of introgression among the Guadalupe Island deinandras; morphological, phenological, and/or habitat differences among those taxa indicate ecological barriers to gene flow and a probable role for ecological divergence in diversification. Biosystematic and molecular phylogenetic data for shrubby tarweeds of Guadalupe Island and another secondarily woody, oceanic-island tarweed lineage, the Hawaiian silversword alliance, reveal strikingly similar evolutionary histories. Both groups violate Baker's Rule by stemming from self-incompatible ancestors in western North America, and each has undergone within-island diversification without evolution of strong sterility barriers among lineages. Evolutionary parallels between these Hawaiian and California Island lineages of Madiinae, first suggested by Carlquist, may reflect characteristics of tarweeds that facilitate insular colonization and adaptive radiation.     

美国在华采集竹类植物标本的历史(1840-2010年)

植物标本采集是植物学研究的重要内容, 与植物引种密切相关。自19世纪以来, 美国植物采集者在全球尤其是中国进行了广泛的植物采集。在众多的植物类群中, 中国的竹类植物引起了美国采集者的极大关注, 并开展了大量调查研究和标本采集工作。研究美国植物采集者在中国采集竹类植物标本的历史, 对了解竹类植物从中国引种到美国的历史具有重要意义。本文基于国内外有关美国在华采集的竹类植物标本数据, 对其学名、采集地、采集人以及采集时间进行整理校对, 分析了美国采集者在华采集竹类植物标本的历史。结果表明: 1840-2010年, 美国在华共采集竹类植物标本960号2,238份, 隶属于25属120种(含变种和变型), 分别占中国竹类属和种数的73.5%和22.5%; 有45位(支)采集者(采集队), 在这些采集者中莫古礼最为重要; 采集地涉及20个省级行政区; 采集时间前后跨度约170年, 主要集中在20世纪上半叶。