Non-woody life-form contribution to vascular plant species richness in a tropical American forest

We provide total vascular plant species counts for three 1-ha plots in deciduous, semi-deciduous and evergreen forests in central Bolivia. Species richness ranged from 297 species and 22,360 individuals/ha in the dry deciduous forest to 382 species and 31,670 individuals/ha in the evergreen forest. Orchidaceae, Pteridophyta and Leguminosae were among the most species-rich major plant groups in each plot, and Peperomia (Piperaceae), Pleurothallis (Orchidaceae) and Tillandsia (Bromeliaceae), all epiphytes, were the most species-rich genera. This dominance of a few but very diverse and/or widespread taxa contrasted with the low compositional similarity between plots. In a neotropical context, these Central Bolivian forest plots are similar in total species richness to other dry deciduous and humid montane forests, but less rich than most Amazonian forests. Nevertheless, lianas, terrestrial herbs and especially epiphytes proved to be of equal or higher species richness than most other neotropical forest inventories from which data are available. We therefore highlight the importance of non-woody life-forms (especially epiphytes and terrestrial herbs) in Andean foothill forest ecosystems in terms of species richness and numbers of individuals, representing in some cases nearly 50% of the species and more than 75% of the individuals. These figures stress the need for an increased inventory effort on non-woody plant groups in order to accurately direct conservation actions. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Two fungi associated with necrotic leaflets of areca palms (Areca catechu)

Information on fungi associated with necrotic leaflets of exotic palms in Thailand is scanty, as previous studies were mainly focused on decaying fronds. This study provides some information regarding fungi associated with necrotic leaflets of exotic palms in Thailand. Specimens in this work were collected from several locations in Chiang Mai province, including natural and planted areas. One new species, Cercospora arecacearum on areca palm (Areca catechu), is described and illustrated. An ITS sequence data analysis confirms the separation of the new Cercospora species from related taxa. Another species, Neorehmia arecae, hitherto only known from areca palm, is newly recorded for Thailand. Furthermore, Wallichia siamensis is a new host for this species.     

松嫩平原盐碱土饱和浸提液与土水比1∶5浸提液间化学参数的换算关系

采用饱和浸提液与土水比1∶5浸提液两种方法分析了松嫩平原94份盐碱土样品的电导率、钠吸附比、主要阳离子(Na⁺、K⁺、Ca²⁺、Mg²⁺)以及总阳离子浓度等化学参数,并对两种方法测定的盐碱化参数相关性进行了研究。结果表明：饱和浸提液电导率、钠吸附比、总阳离子浓度、Na⁺离子浓度与土水比1∶5浸提液相应参数存在极显著的相关关系,其关系方程可用于松嫩平原盐碱土饱和浸提液与1∶5浸提液间化学参数的换算;而K⁺、Ca²⁺、Mg²⁺离子浓度在两种浸提液间不存在相关性。     

Vegetative micro-cloning to sustain biodiversity of threatened Moringa species

Efficient vegetative cloning in vitro requires definition of plant growth regulator regimes for each genotype, and therefore formulation of a uniform culture protocol for a genetically heterogeneous wild or uncultivated plant population is often impossible. The likelihood of cloning a wide array of plant genotypes by avoiding the use of plant growth regulator(s) was explored with Moringa oleifera Lamk., Moringa stenopetala (Baker f.) Cufod, and Moringa peregrina Forssk. ex Fiori tree seedlings. Propagation was achieved by multiple shoot regeneration from the cotyledonary node of decapitated seedlings, followed by axillary shoot growth from single node shoot segments and rooting of excised shoots. All steps were accomplished on basal Murashige and Skoog medium without plant growth regulator supplements. The results revealed competence for generation of multiple shoots from cotyledonary node tissue, stimulated by repeated shoot harvest, in seedlings of all three tree species. Tens of plants per seedling were regenerated in about 4 mo from culture initiation. In a given species clone size was seedling-dependent, which presumably stems from genotypic variability among seedlings in regeneration ability in vitro. By this means the laborious search for a plant growth regulator regime suitable for organogenesis induction and adapted per genotype became redundant, and biodiversity of the seed germplasm could be maintained. The approach ideally suits establishment of clones of wild plants of endangered species, like those of the Moringaceae, species with high ability for producing supplementary shoots, and without the need to add plant growth regulators, including the rooting stage.     

新一代植物志：iFlora

进入21世纪,随着分子生物学及计算机信息等技术的快速发展,人们认知自然的手段和方式发生了根本性的变化。在现有电子植物志（eFlora）的基础上,融入新一代测序技术、DNA条形码数据、地理信息数据和计算机信息技术等新元素的新一代植物志（iFlora）应运而生。iFlora是通过系列关键技术的集成和攻关,构建便捷、准确识别植物和掌握相关数字化信息的新一代植物志（或智能装备）,它将极大地促进植物分类学和系统发育、演化生物学、生态学、生物地理学和保护生物学等相关学科的发展,有效地服务于生物多样性保护和生物资源可持续利用、国家生态安全和社会公共教育等,并进一步提升公众对生物多样性的认识。iFlora的实施,将为培育和拓展物种识别圈（taxasphere）和生物文化圈（bioliterate world）做出应有的贡献,并可能成为引领国际植物学发展新的生长点。     

An asymmetry in niche conservatism contributes to the latitudinal species diversity gradient in New World vertebrates

The Tropical Niche Conservatism hypothesis is a leading explanation for why biodiversity increases towards the equator. The model suggests that most lineages have tropical origins, with few dispersing into temperate regions. However, biotas are comprised of lineages with differing geographical origins, thus it is unclear whether lineages that originated on different continents will exhibit similar patterns of niche conservatism. Here, we summarised biogeographical patterns of New World vertebrates and compared species diversity patterns between families that originated in North and South America. Overall, families with southern origins exhibit niche conservatism with many lineages restricted to the Neotropics, whereas many northern‐origin families are distributed across the Neotropics and the Nearctic. Consequently, northern lineages have contributed to high tropical biodiversity, but southern lineages have contributed relatively little to temperate biodiversity in North America. The asymmetry in niche conservatism between northern and southern lineages is an important contributor to the biodiversity gradient.     

Plant diversity controls arthropod biomass and temporal stability

Understanding the linkages among species diversity, biomass production and stability underlies effective predictions for conservation, agriculture and fisheries. Although these relationships have been well studied for plants and, to a lesser extent, consumers, relationships among plant and consumer diversity, productivity, and temporal stability remain relatively unexplored. We used structural equation models to examine these relationships in a long‐term experiment manipulating plant diversity and enumerating the arthropod community response. We found remarkably similar strength and direction of interrelationships among diversity, productivity and temporal stability of consumers and plants. Further, our results suggest that the frequently observed relationships between plant and consumer diversity occur primarily via changes in plant production leading to changed consumer production rather than via plant diversity directly controlling consumer diversity. Our results demonstrate that extinction or invasion of plant species can resonate via biomass and energy flux to control diversity, production and stability of both plant and consumer communities.     

Beta‐diversity gradients of butterflies along productivity axes

Aim Several lines of evidence suggest that beta diversity, or dissimilarity in species composition, should increase with productivity: (1) the latitudinal species richness gradient is most closely related to productivity and associated latitudinal beta‐diversity relationships have been described, and (2) the scale dependence of the productivity–diversity relationship implies that there should be a positive productivity–beta‐diversity relationship. However, such a pattern has not yet been demonstrated at broad scales. We test if there is a gradient of increasing beta diversity with productivity. Location Canada. Methods Canada was clustered into regions of similar productivity regimes along three remotely sensed productivity axes (minimum and integrated annual productivity, seasonality of productivity) and elevation. The overall (β_j), turnover (β_sim) and nestedness (β_nes) components of beta diversity within each productivity regime were estimated with pairwise dissimilarity metrics and related to cluster productivity with partial linear regression and with spatial autoregression. Tests were performed for all species, productivity breadth‐based subsets (e.g. species occurring in many and a moderate number of productivity regimes), and pre‐ and post‐1970 butterfly records. Beta diversity between adjacent clusters along the productivity gradients was also evaluated. Results Within‐cluster β_j and β_sim increased with productivity and decreased with seasonality. The converse was true for β_nes. All species subsets responded similarly; however, productivity–beta‐diversity relationships were weaker for the post‐1970 temporal subset and strongest for species of moderate breadth. Between‐cluster beta diversity (β_j) and nestedness (β_nes) declined with productivity. Main conclusions As predicted, beta diversity of communities within productivity regimes was observed to increase with productivity. This pattern was driven largely by a gradient of species turnover. Therefore, beta diversity may make an important contribution to the broad‐scale gradient of species richness with productivity. However, this species richness gradient dominates regional beta diversity between productivity regimes, resulting in decreasing between‐productivity dissimilarity with productivity driven by a concurrent decline in nestedness.