Palynological differentiation between genera of the Moraceae family and implications for Amazonian palaeoecology

The Moraceae family is one of the most abundant and ecologically important families in Neotropical rainforests and is very well-represented in Amazonian fossil pollen records. However, difficulty in differentiating palynologically between the genera within this family, or between the Moraceae and Urticaceae families, has limited the amount of palaeoecological information that can be extracted from these records. The aim of this paper is to analyse the morphological properties of pollen from Amazonian species of Moraceae in order to determine whether the pollen taxonomy of this family can be improved. Descriptive and morphometric methods are used to identify and differentiate key pollen types of the Moraceae (mulberry) and Urticaceae (nettle) families which are represented in Amazonian rainforest communities of Noel Kempff Mercado National Park (NKMNP), Northeast Bolivia. We demonstrate that Helicostylis, Brosimum, Pseudolmedia, Sorocea and Pourouma pollen can be identified in tropical pollen assemblages and present digital images of, and a taxonomic key to, the Moraceae pollen types of NKMNP. Indicator species, Maquira coriacea (riparian evergreen forest) and Brosimum gaudichaudii (open woodland and upland savanna communities), also exhibit unique pollen morphologies. The ability to recognise these ecologically important taxa in pollen records provides the potential for much more detailed and reliable Neotropical palaeovegetation reconstructions than have hitherto been possible. In particular, this improved taxonomic resolution holds promise for resolving long-standing controversies over the interpretation of key Amazonian Quaternary pollen records.

Recovery of soil physical properties by green manure, liming, gypsum and pasture and spontaneous native species

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

OFF-LINE SUPERCRITICAL-FLUID EXTRACTION - HIGH-RESOLUTION GAS-CHROMATOGRAPHY APPLIED TO THE STUDY OF MORACEAE SPECIES

Supercritical fluid extraction with CO2, Performed in a home-made system, of rhizomes of Dorstenia bryoniifolia Mart. ex Miq. (Moraceae) and of bark roots of Brosimum gaudichaudii Trecul (Moraceae) afforded crude extracts that were analysed by high resolution gas chromatography (HRGC). The D. bryoniifolia extract contained, besides the previously reported pimpinelin and isobergapten, the furocoumarins psoralen, bergapten, isopimpinelin and the triterpenes alpha- and beta-amyrin and the acetate of the latter. The B. gaudichaudii extract contained a number of terpenoids as well as the previously reported psoralen and bergapten. Supercritical fluid extraction gave extracts qualitatively similar to those obtained by Soxhlet extraction with hexane and, together with off-line HRGC, was shown to be a fast and accurate technique to be used in rapid phytochemical examination.

Associação micorízica em espécies arbóreas, atividade microbiana e fertilidade do solo em áreas degradadas de cerrado

The recuperation of areas used during the construction of the hydroelectric plant, especially in 'borrowed areas', is a difficult and long process since all vegetation and the fertile layer of soil were removed. Interventions in these degraded areas could accelerate the revegetation process. The objective of this research was to evaluate the association of arbuscular mycorrhizal fungi (AMF) in tree species, microbial activity (basal respiration) and fertility of 'cerrado' degraded areas. Soil from two areas, pasture soil and exposed subsoil, were utilized. Organic and mineral fertilization, and liming, were added to the pit for better seedlings' initial growth, where 50 mL of preserved cerrado soil was applied as inoculum of microorganisms. Seedlings of 11 tree species were planted: Anadenanthera falcata (Benth.) Speg ('angico-preto'), Acacia polyphylla D. C. ('monjoleiro'), Stryphnodendron adstringens (Mart.) Coville ('barbatimao'), Dimorphandra mollis Benth ('faveiro'), Hymenaea stigonocarpa Mart. ex Hayne ('jatoba-de-cerrado'), Dipteryx alata Vog. ('baru'), Machaerium acutifolium Vogel ('jacaranda-do-campo'), Schinus terebinthifolia Raddi ('aroeirapimenteira'), Magonia pubescens St. Hil. ('tingui'), Lafoensia pacari St. Hil. ('dedaleira') and Tabebuia aurea (Manso) Benth. & Hook ('ipe-amarelo'). Twelve months later, root samples were colleted at the depth of 0-0.10 m and used for evaluations. The subsoil, as compared to pasture soil, was poor in organic matter and presented less microbial activity. The highest mycorrhizal colonization was seen in the species Acacia polyphylla D. C. (monjoleiro), Magonia pubescens St. Hil. (tingui), Hymenaea stigonocarpa Mart. ex Hayne (jatoba-de-cerrado) and Schinus terebinthifolia Raddi (aroeira-pimenteira). These species could be indicated in revegetation projects in 'cerrado' degraded areas. Plants from both areas showed seedlings form high mycorrhizal colonization and low numbers of spores.

Sporophytic apomixis in polyploid Anemopaegma species (Bignoniaceae) from central Brazil

Apomixis and polyploidy have been important in the evolution of the angiosperms, and sporophytic apomixis has been associated with polyembryony and polyploidy in tropical floras. We studied the occurrence of polyembryony in populations of tetraploid Anemopaegma acutifolium, A.arvense and A.glaucum from the Brazilian cerrados, and histological features of sexual and apomictic processes were investigated in A.acutifolium. All populations and species were polyembryonic (68.9-98.4% of seeds). Normal double fertilization occurred in most ovules, with exceptions being that 3% of ovules were penetrated but not fertilized and in 4% of ovules both synergids were penetrated. The penetration of both synergids suggests a continuous attraction of pollen tubes and polyspermy. Adventitious embryo precursor cells (AEPs) arose from nucellar and integumental cells of the ovule in pollinated and unpollinated A.acutifolium, indicating sporophytic apomixis. However, further embryo and endosperm development required pollination and fertilization. This pseudogamy also allows concurrent sexual embryo development. Similar polyembryony rates and polyploidy indicated that A.arvense and A.glaucum are also apomictic, forming an agamic complex similar to that observed for some species of confamilial, but not closely related Handroanthus. The co-occurrence of apomixis and polyploidy in different groups of Bignoniaceae indicates homoplasious origin of these agamic complexes. © 2013 The Linnean Society of London.

Comportamento e dieta de Chiropotes albinasus (I. Geoffroy & Deville, 1848) - cuxiú-de-nariz-vermelho

Os cuxiús-de-nariz-vermelho são primatas neotropicais pouco conhecidos e encontramse na Lista de Espécies Ameaçadas da IUCN na categoria “Ameaçada de Extinção”. Este estudo foi desenvolvido com um grupo desta espécie de primatas na RPPN Cristalino, MT. Foi estudado o orçamento de atividades, uso de espaço e a ecologia alimentar do grupo, através do método de “Varredura Instantânea”. O grupo foi acompanhado durante 6 meses, incluindo 2 meses na estação chuvosa e 4 meses na estação seca. As categorias comportamentais Deslocamento, Alimentação e Parado foram responsáveis por 81,17% dos registros gerais de atividades. Os animais utilizaram com maior intensidade o estrato intermediário da floresta (entre 16 e 20 metros). A dieta do grupo foi preferencialmente frugívora (82,52%), mas também se alimentaram de invertebrados. Cerca de 18 famílias botânicas foram consumidas. Sendo os taxons Arrabidaea sp. e Brosimum latescens os mais comuns. Nos meses de seca houve um maior acréscimo de outros itens alimentares, como flores e invertebrados na dieta dos cuxiús. O tamanho do grupo variou entre 1 e 19 indivíduos ao longo do estudo, assim como a estrutura sexual que também variou bastante. Foi observado o cuidado parental por parte dos machos, além de interações agonísticas interespecíficas entre Ateles marginatus e Sapajus apella.

Contribution of woody habitat islands to the conservation of birds and their potential ecosystem services in an extensive Colombian rangeland

The conservation of birds and their habitats is essential to maintain well-functioning ecosystems including human-dominated habitats. In simplified or homogenized landscapes, patches of natural and semi-natural habitat are essential for the survival of plant and animal populations. We compared species composition and diversity of trees and birds between gallery forests, tree islands and hedges in a Colombian savanna landscape to assess how fragmented woody plant communities affect forest bird communities and how differences in habitat characteristics influenced bird species traits and their potential ecosystem function. Bird and tree diversity was higher in forests than in tree islands and hedges. Soil depth influenced woody species distribution, and canopy cover and tree height determined bird species distribution, resulting in plant and bird communities that mainly differed between forest and non-forest habitat. Bird and tree species and traits widely co-varied. Bird species in tree islands and hedges were on average smaller, less specialized to habitat and more tolerant to disturbance than in forest, but dietary differences did not emerge. Despite being less complex and diverse than forests, hedges and tree islands significantly contribute to the conservation of forest biodiversity in the savanna matrix. Forest fragments remain essential for the conservation of forest specialists, but hedges and tree islands facilitate spillover of more tolerant forest birds and their ecological functions such as seed dispersal from forest to the savanna matrix.

Species occurrence and richness of lichen, bryophytes and vascular plants near Abisko, Sweden and Toolik lake, Alaska

Little is known about the impact of changing temperature regimes on composition and diversity of cryptogam communities in the Arctic and Subarctic, despite the well-known importance of lichens and bryophytes to the functioning and climate feedbacks of northern ecosystems. We investigated changes in diversity and abundance of lichens and bryophytes within long-term (9-16 years) warming experiments and along natural climatic gradients, ranging from Swedish subarctic birch forest and subarctic/subalpine tundra to Alaskan arctic tussock tundra. In both Sweden and Alaska, lichen diversity responded negatively to experimental warming (with the exception of a birch forest) and to higher temperatures along climatic gradients. Bryophytes were less sensitive to experimental warming than lichens, but depending on the length of the gradient, bryophyte diversity decreased both with increasing temperatures and at extremely low temperatures. Among bryophytes, Sphagnum mosses were particularly resistant to experimental warming in terms of both abundance and diversity. Temperature, on both continents, was the main driver of species composition within experiments and along gradients, with the exception of the Swedish subarctic birch forest where amount of litter constituted the best explanatory variable. In a warming experiment in moist acidic tussock tundra in Alaska, temperature together with soil ammonium availability were the most important factors influencing species composition. Overall, dwarf shrub abundance (deciduous and evergreen) was positively related to warming but so were the bryophytes Sphagnum girgensohnii, Hylocomium splendens and Pleurozium schreberi; the majority of other cryptogams showed a negative relationship to warming. This unique combination of intercontinental comparison, natural gradient studies and experimental studies shows that cryptogam diversity and abundance, especially within lichens, is likely to decrease under arctic climate warming. Given the many ecosystem processes affected by cryptogams in high latitudes (e.g. carbon sequestration, N2-fixation, trophic interactions), these changes will have important feedback consequences for ecosystem functions and climate.

Vegetation, soil and site characteristics of samples taken along the Yamal Transet in 2007-2008

The overarching goal of the Yamal portion of the Greening of the Arctic project is to examine how the terrain and anthropogenic factors of reindeer herding and resource development combined with the climate variations on the Yamal Peninsula affect the spatial and temporal patterns of vegetation change and how these changes are in turn affecting traditional herding of the indigenous people of the region. The purpose of the expeditions was to collect groundobservations in support of remote sensing studies at four locations along a transect that traverses all the major bioclimate subzones of the Yamal Peninsula. This data report is a summary of information collected during the 2007 and 2008 expeditions. It includes all the information from the 2008 data report (Walker et al. 2008) plus new information collected at Kharasavey in Aug 2008. The locations included in this report are Nadym (northern taiga subzone), Laborovaya (southern tundra = subzone E of the Circumpolar Arctic Vegetation Map (CAVM), Vaskiny Dachi (southern typical tundra = subzone D), and Kharasavey (northern typical tundra = subzone C). Another expedition is planned for summer 2009 to the northernmost site at Belyy Ostrov (Arctic tundra = subzone B). Data are reported from 10 study sites - 2 at Nadym, 2 at Laborovaya, and 3 at Vaskiny Dachi and 3 at Kharasavey. The sites are representative of the zonal soils and vegetation, but also include variation related to substrate (clayey vs. sandy soils). Most of the information was collected along 5 transects at each sample site, 5 permanent vegetation study plots, and 1-2 soil pits at each site. The expedition also established soil and permafrost monitoring sites at each location. This data report includes: (1) background for the project, (2) general descriptions and photographs of each locality and sample site, (3) maps of the sites, study plots, and transects at each location, (4) summary of sampling methods used, (5) tabular summaries of the vegetation data (species lists, estimates of cover abundance for each species within vegetation plots, measured percent ground cover of species along transects, site factors for each study plot), (6) summaries of the Normalized Difference Vegetation Index (NDVI) and leaf area index (LAI) along each transect, (7) soil descriptions and photos of the soil pits at each study site, (8) summaries of thaw measurements along each transect, and (9) contact information for each of the participants. One of the primary objectives was to provide the Russian partners with full documentation of the methods so that Russian observers in future years could repeat the observations independently.

Plant species, biomass and environmental characteristics of relevés along the North America Arctic bioclimate gradient

Question: How do interactions between the physical environment and biotic properties of vegetation influence the formation of small patterned-ground features along the Arctic bioclimate gradient? Location: At 68° to 78°N: six locations along the Dalton Highway in arctic Alaska and three in Canada (Banks Island, Prince Patrick Island and Ellef Ringnes Island). Methods: We analysed floristic and structural vegetation, biomass and abiotic data (soil chemical and physical parameters, the n-factor [a soil thermal index] and spectral information [NDVI, LAI]) on 147 microhabitat releves of zonalpatterned-ground features. Using mapping, table analysis (JUICE) and ordination techniques (NMDS). Results: Table analysis using JUICE and the phi-coefficient to identify diagnostic species revealed clear groups of diagnostic plant taxa in four of the five zonal vegetation complexes. Plant communities and zonal complexes were generally well separated in the NMDS ordination. The Alaska and Canada communities were spatially separated in the ordination because of different glacial histories and location in separate floristic provinces, but there was no single controlling environmental gradient. Vegetation structure, particularly that of bryophytes and total biomass, strongly affected thermal properties of the soils. Patterned-ground complexes with the largest thermal differential between the patterned-ground features and the surrounding vegetation exhibited the clearest patterned-ground morphologies.

A descriptive account of the palo de vaca; or cow tree of the Caracas, with a chemical analysis of the milk and bark.

Mode of access: Internet.