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Here we report a fossil flora from the Miocene Toupi Formation in Jiangxi Province, southeastern China, including megafossil genera Pinus, Podocarpus, Calocedrus, Cinnamomum, Quercus, Lithocarpus, Carya, Palaeocarya, Acer, and Yua. Among them, Yua jiangxiensis n. sp. is the first fossil record of the genus in Asia. A palynological analysis in this study reveals that the palyno-assemblage contains Selaginella, Pteris, Pinus, Picea, Quercus, Fagus, Carya, Ilex, and Rutaceae. Based on Integrated Plant Records (IPR) vegetation analysis, it is suggested that the fossil flora represents an evergreen broad-leaved forest, and the occurrence of tropical and subtropical Cinnamomum supports a warm and moist climate in the region during the middle Miocene.

Yellowwood or Podocarpus (spp.) holds the esteemed biodiversity status, as key forest species in the mist-belt Afromontane forests of southern Africa. The podocarps are listed as endangered species...

Fossil plants in the Tierra del Fuego Province, Argentinean Patagonia, are known since the expedition of Charles Darwin to the Beagle channel. However, only a few fossil plants have been described. In this work, a new fossil leaf collection is studied. It was collected from outcrops of the Cullen Formation (middle Miocene) located in the Atlantic coast of Tierra del Fuego, Patagonia, Argentina. Over two hundred pieces were collected in three localities: Cabo Espiritu Santo, Arroyo Beta, and Canadon de los Mineros. The taxonomic studies reveal the presence of nine fossil species; six of them are related to Nothofagus Blume (Nothofagaceae), one to Myrtaceae, one to Gesneriaceae and the last one to the genus Podocarpus Labill. Our study agrees with previous ones, which suggested that the Nothofagaceae were dominant in the Cullen Formation area, and support the development of a cold temperate and humid forest in the area. The megafloral association studied result similar to others paleofloras developed in Patagonia during the Neogene, according to the cluster analysis performed. Finally, it was characterized like a Subantartic paleoflora sensu Troncoso & Romero.

International audience; Quantitative pollen-based reconstruction of Holocene plant abundance has not been attempted in the tropics so far. Tropical vegetation is characterized by a large number of entomophilous species and pollen-vegetation modelling for such plants is widely considered too problematic. However, there is a pressing need for quantitative reconstructions of Holocene plant cover in tropical regions to better assess climate- and human-induced environmental crises over time. Of particular note is the environmental crisis at the end of the ‘African Humid Period’ (c. 3 thousand years before present [ka BP]) which remains unquantified. Here, we present results from a pilot study in the Cameroon highlands including estimates of relative pollen productivity (RPP) for major taxa of the Afromontane forests and grasslands using the Extended R-Value (ERV) model, and the first reconstructions of past regional and local Holocene plant cover using the Landscape Reconstruction Algorithm (LRA). RPP estimates were obtained for 12 taxa. We found that Celtis, Alchornea, Syzygium, Macaranga/Mallotus, Nuxia type, and Schefflera have RPPs larger than Poaceae, and Moraceae, Combretaceae/Melastomataceae, Prunus africana/Rubus pinnatus, Cyperaceae, and Podocarpus lower RPPs than Poaceae. The LRA was applied to three Holocene pollen records from Cameroon (Bambili, Mbi, Mbalang) and one from Nigeria (Tilla). The results confirm the abruptness of the forest collapse in Cameroon at 3 ka BP, and suggest that it was faster and of larger magnitude than earlier anticipated. The LRA reconstruction also indicates that the regional landscape in the mountain region was more open than uncorrected pollen percentages alone suggest. Moreover, it supports the earlier interpretation of a dense forest at Bambili 11–3.5 ka BP and the local occurrence of Afromontane forest taxa at Mbalang in the Mid-Holocene.

Southern Brazil's highland Araucaria forest is ancient, diverse and unique, but its future is under significant threat from 20th Century habitat loss and 21st Century climate change. Palaeoecological studies have revealed that it expanded rapidly over highland grasslands around 1,000 years ago, but whether this expansion was caused by human land use or climate change has been a topic of considerable debate. Discriminating between these potential drivers has so far not been possible with fossil pollen, however, as the palynological representation of floristic and structural differences in Araucaria forest remains poorly understood. Here, we address this shortcoming using modern pollen rain from moss polsters and vegetation surveys in forest areas with minimal current human disturbance. We show that forest plots with evident structural differences lack consistent differences in their floristic composition and cannot be reliably distinguished by their pollen spectra. We quantify pollen-vegetation relationships for 27 key tree genera of Araucaria forest, showing that, despite significant intra-taxon variability, 22 of these are under-represented or absent in the pollen record. These palynologically under-represented and silent taxa include many of the forest’s most ecologically important tree species, with only Araucaria, Lamanonia, Podocarpus, Myrsine and Clethra being more abundant in the pollen rain than vegetation. Our results suggest that subtle structural changes in Araucaria forest, as well as moderate to significant floristic changes, may not be clearly distinguished in fossil pollen records -- an important limitation when attempting to identify past human and climatic impacts on Araucaria forest via pollen analysis.\ud \ud Key words: Araucaria forest, pollen, moss polsters, modern analogues, human impact

New records of Micropeltidaceae are reported on leaves of Podocarpus parlatorei leaves in the Yungas, Argentina. A new variety, Micropeltis albomarginata var. macrospora is proposed. Dictyopeltis applanata is recorded for the first time in Argentina. Descriptions, illustrations, data on geographical distribution, habitat, and notes are provided. Se reportan nuevos registros de Micropeltidaceae sobre hojas de Podocarpus parlatorei en las Yungas, Argentina. Se propone una nueva variedad, Micropeltis albomarginata var. macrospora. Se registra por primera vez para la Argentina a Dictyopeltis applanata. Se proporcionan descripciones, ilustraciones, datos de distribución geográfica y hábitat. Fil: Gallo, María Cecilia Fátima. Universidad Nacional de Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; Argentina Fil: Romero, Andrea Irene. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Micología y Botánica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Micología y Botánica; Argentina Fil: Catania, Myriam del Valle. Fundación Miguel Lillo. Dirección de Botánica; Argentina

Abra de Zamora is an important biodiversity hotspot in southern Ecuador. Between 1938 and 2010, eleven species of frogs were described from here: Lynchius flavomaculatus, Gastrotheca psychrophila, Pristimantis balionotus, P. colodactylus, P. cryptomelas, P. percultus, P. versicolor, P. vidua, Telmatobius cirrhacelis, P. andinognomus, and Atelopus podocarpus. Unfortunately, many of these species were not re-encountered after their original description, and for the majority DNA samples were not available, making their phylogenetic position unknown. In this study, we assess the current state of the amphibians from Abra de Zamora, by: i. redescribing the species which were first reported from the area, by contributing genetic delimitation (for L. flavomaculatus, P. balionotus, P. colodactylus, P. percultus, and P. vidua), release call (L. flavomaculatus) and advertisement call descriptions (for P. balionotus, P. vidua and P. versicolor); ii. presenting an updated amphibian species list of Abra de Zamora, with the description of two additional Pristimantis species; iii. updating the distribution of these species, including data collected in similar montane habitats from surrounding areas; and iv. amending recommendations regarding their conservation status.

The genus Dyscolus Dejean, 1831 is a highly speciose taxon of neotropical Carabidae and the major component of high-altitude ground beetle communities in the tropical Andes. The aim of this study is threefold: (i) refine the taxonomic position of the equatorial members of Dyscolus using molecular data, (ii) provide a delimitation of the species found in Ecuador in paramo and montane forest environments based on a robust combination of molecular and morphological data, (iii) describe the new species and take the nomenclatural decisions made necessary by the results of this study. The seclusion of Dyscolus from more basal platynine clades including Platynus , Batenus and Glyptolenus , is supported by a phylogenetic analysis of the COI marker. Twenty-five new species of Dyscolus , most of them microendemic, are described and illustrated: D. aquator Moret sp. nov. (Tandayapa, Pichincha), D. arauzae Moret sp. nov. (Mt Cayambe, Pichincha), D. arborarius Moret sp. nov. (Parque Nacional Yacuri, Loja), D. barragani Moret sp. nov. (Mt Ayapungu, Chimborazo), D. crespoae Moret sp. nov. (Parque Nacional Podocarpus, Zamora-Chinchipe), D. danglesi Moret sp. nov. (Parque Nacional Yacuri, Loja), D. donosoi Moret sp. nov. (Parque Nacional Podocarpus, Zamora-Chinchipe), D. eleonorae Moret sp. nov. (Cotopaxi and Pichincha provinces), D. famelicus Moret sp. nov. (Papallacta, Napo), D. giselae Moret sp. nov. (Reserva Otonga, Cotopaxi), D. globoculus Moret sp. nov. (Parque Nacional Podocarpus, Zamora-Chinchipe), D. gobbii Moret sp. nov. (Guamani and Mt Antisana, Pichincha), D. incommunis Moret sp. nov. (Tandayapa, Pichincha), D. marini Moret sp. nov. (Parque Nacional Podocarpus, Loja), D. piscator Moret sp. nov. (Guamani, Napo), D. placitus Moret sp. nov. (Guamani, Napo), D. ravidus Moret sp. nov. (Parque Nacional Podocarpus, Loja), D. rivinus Moret sp. nov. (Reserva Otonga, Cotopaxi), D. rugitarsis Moret sp. nov. (Parque Nacional Yacuri, Loja), D. ruizi Moret sp. nov. (Parque Nacional Podocarpus, Loja and Zamora), D. salazarae Moret sp. nov. (Parque Nacional Podocarpus, Loja), D. silvestris Moret sp. nov. (Papallacta, Napo), D. sulcipedis Moret sp. nov. (Parque Nacional Yacuri, Loja), D. verecundior Moret sp. nov. (Mt Illiniza and Mt Corazon, Pichincha) and D. verecundissimus Moret sp. nov. (Mt Chimborazo, Chimborazo). Dyscolus palatus Moret, 1998 is newly synonymized with D. denigratus (Bates, 1891). We demonstrate the subgenus Hydrodyscolus Moret, 1996 to be polyphyletic and therefore consider it a junior synonym of Dyscolus Dejean, 1831.

Termites are one of the key ecosystem engineers in tropical forests where they play a major role in decomposition rates, both above and belowground. The interest in termite ecology and biogeography has increased in the last few decades; however, the lack of comparable data has limited the wider impact of termite research. For Ecuador, termite studies are relatively rare and comparable data that are collected using standardized sampling methods are missing. In this study, we aim to 1) provide comparable data of termite species and feeding-group diversity from two primary forests in Ecuador and 2) explore the differences in termite species and feeding-group diversity between the two forest sites. Sampling took place in the national parks of Yasuní and Podocarpus where three belt transects (100 × 2 m) following Jones and Eggleton (2000) were conducted in each forest. We found that termite species richness was higher in Yasuní (56 species) than in Podocarpus (24 species) and that 57% of the sampled termite genera had never previously been recorded in Ecuador. The inter-site species dissimilarity was almost complete (Bray Curtis (±SD), 0.91 ± 0.01), which may have been linked to the difference in tree density and species richness in the two forests. Termite feeding-groups diversity was significantly higher in Yasuní than in Podocarpus with the exception of soil-feeding termites which may have been due to competition between humus- and soil-feeding species.

Accumulating evidence suggests that species sensitivity to climatic change is strongly related to their ecological niches, which are somewhat evolutionary conserved. Insofar as this is true, climate change-driven extinctions may be non-random with respect to phylogeny, and entire branches of the tree of life might be lost. In mountainous regions, where macroecological conditions change abruptly with elevation, evolutionarily lineages may show deep phylogenetic turnover along elevational belts, and such “layering” of the phylogeny may lead to disproportionate losses of phylogenetic diversity. Here, we explored phylogenetic alpha and beta diversity patterns of plant assemblages among six elevational belts at Kilimanjaro (i.e. savanna woodland, lower montane forest, middle-montane Ocotea forest, upper-montane Podocarpus forest, Erica subalpine bushland and Helichrysum alpine scrubland). Specifically, we aimed at determining the degree of elevational turnover of plant evolutionary lineages as a diagnostic tool to assess phylogenetic diversity threats owing to shifting environmental conditions. We found relatively deep phylogenetic discontinuities that roughly matched the main modern vegetation types in East Africa, this is, subalpine-alpine vegetation, montane forests and savannas lowlands. However, the upper-montane Podocarpus forest was phylogenetically closer to subalpine-alpine vegetation than to middle (Ocotea) and lower montane forests, despite all these forest belts constituted a floristically integrated unit. Phylogenetic diversity followed a hump-shape relationship with elevation, with significantly high values in lower montane forest and lower than expected scores in savanna, subalpine and alpine belts. Overall, the phylogenetic layering of Kilimanjaro flora reported here suggests that a disproportionate amount of phylogenetic diversity in mountainous regions might be at risk, although the generality of this pattern is yet to be confirmed. In the particular case of Kilimanjaro, human population growth represents a pervasive threat to montane forest, and particularly to the phylogenetically singular remnants of lower montane forest. Besides, climate-change induced fires in the subalpine belt are causing over-riding shrinkage of the upper-montane Podocarpus forest from the timberline. Should these continuing pressures of global change persist, the montane forests of Kilimanjaro may experience substantial shrinking within the next decades, trapped between the “hammer and the anvil” of climate and land-use change.

The zonal vegetation of the subtropics with year-round rain (“wet subtropics”) consists of evergreen and semi-evergreen laurophyllous forests. Because they are located on the eastern sides of the continents, these forests receive rainfall throughout the year; towards the interior of the continents, maximum rainfall shifts into summer. Particularly in the Southern Hemisphere, these forests often include archaic conifers of the genera Araucaria and Podocarpus. It is remarkable that grassland occurs extensively, particularly in South America (campo, pampa), but also in South Africa, despite the consistently humid climate that would allow forest to occur. This grassland is considered to be a relic of postglacial dry periods; it is maintained by fire and grazing.

Vegetation dynamics during previous warm interglacial periods shed light on the human impacts on natural ecosystems during the Holocene. However, reliable terrestrial records that span such periods are rare and provide little information on regional scale. Here we present a high-resolution marine pollen record from the northern South China Sea, which reveals that during five peak interglacial periods, Marine Isotope Stages 13a, 11c, 9c, 5e and 1 (the Holocene), the vegetation successions in southern China were similar. At the beginning of each interglacial period, tropical rainforest conifers, which include Dacrydium, Dacrycarpus and Podocarpus, and associated broadleaved taxa, such as Altingia, expanded quickly at the expense of the subtropical/temperate montane conifer Pinus. Near the end of the warm periods, Pinus recovered and the tropical taxa retreated. However, the Holocene displays subtle but significant differences in which the species turnover was interrupted and the rainforest conifers did not fully expanded. The Mg/Ca-based sea surface temperature record from the same site reveals that temperature was the major control of the rise and fall of the peak interglacial vegetation. However, exceptionally high charcoal fluxes during the Holocene suggest that human activities through land-use modifications completely, and possibly permanently, altered the natural vegetation trend five to six thousand years ago. Human land use changed the evolution of vegetation in southern China 6,000 years ago, according to analyses of a high-resolution marine pollen record.

The origin of modern disjunct plant distributions in the Brazilian Highlands with strong floristic affinities to distant montane rainforests of isolated mountaintops in the northeast and northern Amazonia and the Guyana Shield remains unknown. We tested the hypothesis that these unexplained biogeographical patterns reflect former ecosystem rearrangements sustained by widespread plant migrations possibly due to climatic patterns that are very dissimilar from present-day conditions. To address this issue, we mapped the presence of the montane arboreal taxa Araucaria, Podocarpus, Drimys, Hedyosmum, Ilex, Myrsine, Symplocos, and Weinmannia, and cool-adapted plants in the families Myrtaceae, Ericaceae, and Arecaceae (palms) in 29 palynological records during Heinrich Stadial 1 Event, encompassing a latitudinal range of 30°S to 0°S. In addition, Principal Component Analysis and Species Distribution Modelling were used to represent past and modern habitat suitability for Podocarpus and Araucaria. The data reveals two long-distance patterns of plant migration connecting south/southeast to northeastern Brazil and Amazonia with a third short route extending from one of them. Their paleofloristic compositions suggest a climatic scenario of abundant rainfall and relative lower continental surface temperatures, possibly intensified by the effects of polar air incursions forming cold fronts into the Brazilian Highlands. Although these taxa are sensitive to changes in temperature, the combined pollen and speleothems proxy data indicate that this montane rainforest expansion during Heinrich Stadial 1 Event was triggered mainly by a less seasonal rainfall regime from the subtropics to the equatorial region., This work was funded by FAPESP research grant 2015/50683-2 to P.E. De Oliveira, VULPES Project, Belmount Forum.

Palynological study from the Dharmasthali Formation exposed in the northern part of Kathmandu valley revealed the composition of forest vegetation that were growing in middle Pleistocene (780 kyrs BP) in this area. In a total fifteen samples were collected from the 46 m exposed section for the palynological study. The profile can be divided into two zones on the basis of pollen assemblages. The lower part (DF-I) is dominated by Pteridophyte spores such as Lygodium, Polypodium, Cyathea and Pteris. The dominance of Pteridophytes indicate that the forest floor was moist and humid. The tree pollen consists of Abies, Pinus, Quercus, Podocarpus and Alnus. Other Gymnosperms such as Picea and Tsuga were represented by very low percentage. Poaceae and Cyperaceae show their strong presence indicating grassland and wetland conditions around the depositional basin. In the upper zone (DF-II) there is increase of Gymnosperms such as Picea and Abies. The subtropical Gymnosperm Podocarpus decreased while Tsuga completely became absent in this zone. Cold climate preferring trees such as Cedrus, Betula, Juglans and Ulmus appeared first time in this zone. The climate became even colder and drier in the upper part of the section. Near water plants such as Cyperaceae and Typha show their dominance in this zone. The plant assemblages from bottom part of the Dharmasthali Formation indicate warm climate condition which was becoming colder after 780 kyrs towards the top part of the sequence. Bulletin of Department of Geology, vol. 20-21, 2018, pp:37-48

Elevational diversity gradients are typically studied without considering the complex small-scale topography of large mountains, which generates habitats of strongly different environmental conditions within the same elevational zones. Here we analyzed the importance of small-scale topography for elevational diversity patterns of hyperdiverse tropical leaf beetles (Coleoptera: Chrysomelidae). We compared patterns of elevational diversity and species composition of beetles in two types of forests (on mountain ridges and in valleys) and analyzed whether differences in the rate of species turnover among forest habitats lead to shifts in patterns of elevational diversity when scaling up from the local study site to the elevational belt level. We sampled beetle assemblages at 36 sites in the Podocarpus National Park, Ecuador, which were equally distributed over two forest habitats and three elevational levels. DNA barcoding and Poisson tree processes modelling were used to delimitate putative species. On average, local leaf beetle diversity showed a clear hump-shaped pattern. However, only diversity in forests on mountain ridges peaked at mid-elevation, while beetle diversity in valleys was similarly high at low- and mid-elevation and only declined at highest elevations. A higher turnover of species assemblages at lower than at mid-elevations caused a shift from a hump-shaped diversity pattern found at the local level to a low-elevation plateau pattern (with similar species numbers at low and mid-elevation) at the elevational belt level. Our study reveals an important role of small-scale topography and spatial scale for the inference on gradients of elevational species diversity.

Long-standing arguments regarding the early cultural transition, the domestication of plants and the impacts of climate change on past Egyptian societies remain contentious. In this paper, we demonstrate that grazing started at our study site, Kom El-Khilgan in the NE Nile Delta, ca. 7000 years ago, which was several hundred years prior to crop farming. We examined pollen-spores and non-pollen palynomorphs (NPP) in a 1-m-deep sediment profile (KH-1) in the study site, defined archaeologically as the Pre-Dynastic (>5.9 ka) in age. Our results show that before ca. 7.0 ka, major floods prevailed in the Nile Delta, as highly-concentrated Podocarpus and Polypodiaceae were transported from the East African highlands and Cyperaceae of higher Nile flow indication. This humid phase was succeeded by a brief period of drying climate ca. 7.0–6.6 ka, allowing the entry of the first settlers who commenced grazing their animals on previously inundated wetlands. This change is indicated by the remarkable increase in fungal spores (Cercophora, Sordaria, Coniochaeta cf. Ligniaria) from accumulations of animal dung. At ca. 6.6 ka, the abrupt appearance of domesticated cereal pollen (Poaceae >35 μm) and cereal grass pathogens (Pericornia and Sorosporium) suggests an amelioration of the climate that allowed the introduction of cereal crops and related water management activities. Grazing and cropping co-existed for the remainder of the record during the time when there occurred a mega-tendency of climate drying towards recent time. A drought event recognized ca. 4.2 ka led to the collapse of the Old Kingdom.

The effects of climate change on the lowland vegetation of Amazonia during the last glacial cycle are partially known for the middle and late Pleniglacial intervals (late MIS 3, 59–24 ka and MIS 2, 24–11 ka), but are still unclear for older stages of the last glacial and during the last interglacial. It is known that a more seasonal dry-wet climate caused marginal forest retraction and together with cooling rearranged forest composition to some extent. This is observed in pollen records across Amazonia depicting presence of taxa at glacial times in localities where they do not live presently. The understanding of taxa migration is hindered by the lack of continuous interglacial-glacial lowland records. We present new data from a known locality in NW Amazonia (Six Lakes Hill), showing a vegetation record that probably started during MIS 5 (130–71 ka) and lasted until the onset of the Holocene. The vegetation record unravels a novel pattern in tree taxa migration: (1) from the beginning of this cycle Podocarpus and Myrsine are recorded and (2) only later do Hedyosmum and Alnus appear. The latter group is largely restricted to montane biomes or more distant locations outside Amazonia, whereas the first is found in lowlands close to the study site on sandy soils. These findings imply that Podocarpus and Myrsine responded to environmental changes equally and this reflects their concomitant niche use in NW Amazonia. Temperature drop is not discarded as a trigger of internal forest composition change, but its effects are clearer later in the Pleniglacial rather than the Early Glacial. Therefore early climatic/environmental changes had a first order effect on vegetation that invoke alternative explanations. We claim last glacial climate-induced modifications on forest composition favoured the expansion of geomorphologic-soil related processes that initiated forest rearrangement.

We describe a new species native to Ecuador and Peru, Miconia complanata . This species has been collected from two different localities: Parque Nacional Podocarpus (Ecuador) and Cordillera del Condor (Ecuador and Peru). The strongly quadrangular to winged stem, ridged nodes and coriaceous leaves make this species distinctive even within a large genus.

The pollen, spore and organic-walled dinoflagellate cyst associations of two marine sediment cores from the Java Sea off the mouths of Jelai River (S Kalimantan) and Solo River (E Java) reflect environment and vegetation changes for the last ca 3500 years. A decline in primary forest taxa (e.g. Agathis, Allophylus, Dacrycarpus, Dacrydium, Dipterocarpaceae, Phyllocladus and Podocarpus) suggest that the major change in vegetation is caused by forest canopy disturbance possibly as a consequence of human activity. The successive increase in pollen of pioneer tress/shrubs and herb taxa (e.g. Acalypha, Ficus, Macaranga/Mallotus, Trema, Pandanus) indicate the development of secondary vegetation. In Java these changes started much earlier (ca at 2950 cal yr BP) than in Kalimantan (ca at 910 cal yr BP) and seem to be more severe. Changes in the marine realm, reflected by the dinoflagellate cyst association, correspond to the changes in vegetation on land. They reflect a gradual change from relatively well ventilated to more hypoxic bottom/pore water conditions in a more eutrophic environment. Near the coast of Java, the shift of the water trophic status took place between ca 820 and 500 cal yr BP, while near the coast of Kalimantan it occurred as late as at the beginning of the 20th century. We observe an increasing amount of the cysts of Polykrikos schwartzii, P. kofoidii, Lingulodinium machaerophorum, Nematosphaeropsis labyrinthus and Selenopemphix nephroides at times of secondary vegetation development on land, suggesting that human induced terrestrial changes possibly affected the marine environment as well, most likely through increased eutrophication and pollution.

Standing dead trees (or snags) are an important component of forest ecosystems, especially for tree cavity-nesting vertebrate species, but their prevalence in South African forests remains under studied. Consequently, we investigated forest structure, and the presence and abundance of snags in six southern mistbelt forests in the Eastern Cape, South Africa. These forests have had varying levels of timber extraction over the past 150 years or more. We found snags were relatively rare in all six forests (

This study carried out in the Sudanese field of Cote d'Ivoire aims to contribute to the safeguarding of Ivorian flora through the valorization of plants with decorative potentiality of the North of Cote d'Ivoire. The inventory method used is the roaming survey. It consisted of walking in different directions around large cities with different backgrounds and listing all the plant species with decorative potential encountered, regardless of their size. These species have been analyzed at the National Center for Floristics (NCF). These surveys allowed usto collect 287 plant species divided between 220 genera and 79 botanical families, with a predominance of herbs. The most abundant families are Fabaceae, Apocynaceae and Acanthaceae. Of these species, 73.5% are Phanerophytes and 0.3% epiphytes. Also, an Ivorian endemic species (GCI) Cyphostemma ornatum A.Chev. exHutch. & Dalziel (Vitaceae) was also enumerated. Thirteen species or 4.52% are considered introduced species (i). At the ecological level, hydrophytic species and the species like Senna podocarpus Guill. & Perr. (Fabaceae) which is a hardy plant has been inventoried. These results show a great decorative floristic richness in the Sudanian field. This work contributed to the knowledge of the composition and the diversity of the plants with decorative potentiality of the Sudanese field of Cote d'Ivoire.Cette etude realisee dans le domaine soudanais de la Cote d’Ivoire a pour objectif de contribuer a la sauvegarde de la flore ivoirienne a travers la valorisation des plantes a potentialite decorative du Nord de la Cote d’Ivoire. La methode d’inventaire utilisee est le releve itinerant. Elle a consiste a parcourir dans differentes directions autour des grandes villes ayant differents milieux et a recenser toutes les especes vegetales a potentialite decorative rencontrees, sans tenir compte de leur taille. Ces especes ont ete analysees au Centre National de Floristique (CNF). Ces releves nous ont permis de recolter 287 especes vegetales reparties entre 220 genres et 79 familles botaniques, avec une predominance des herbes. Les familles les plus abondantes sont celles des Fabaceae, des Apocynaceae et des Acanthaceae. Parmi ces especes, 73,5 % sont des Phanerophytes et 0,3 % des epiphytes. Aussi, une espece endemique ivoirienne (GCI) Cyphostemma ornatum A.Chev. exHutch. & Dalziel (Vitaceae) a ete egalement recensee. Treize especes soit 4,52% sont considerees comme especes introduites (i). Au niveau ecologique, des especes hydrophytes et l’espece comme Senna podocarpus Guill. &Perr. (Fabaceae) qui est une des plantes rustiques a ete inventoriee. Ces resultats montrent une grande richesse floristique decorative dans le domaine soudanien. Ces travaux ont contribue a la connaissance de la composition et de la diversite des plantes a potentialite decorative du domaine soudanais de la Cote d’Ivoire.

This study examines a one-million-year pollen record from a 194-m-long Lake Magadi core (HSPDP-MAG14-2A) in the south Kenya Rift Valley. The pollen indicate a general trend through the last 740 kyr from wetter conditions to generally drier environments. Grassland dominated with less common Podocarpus and Cyperaceae in a sparse flora between 1000 and 740 ka. Poaceae, woodland and herbaceous plants are common through the remaining core and abundant between 740 and 528 ka and after 200 ka. Pollen diversity increased after 200 ka. Podocarpus and Cyperaceae reached a peak abundance at ~575 ka with a subsequent decline that suggests a progressive increase in aridity, interrupted by wetter intervals. Podocarpus-dominated forests expanded and contracted many times during the Quaternary and document an anti-phased relationship with data from Lake Malawi. Similar anti-phased correlations are noted for herbaceous plants, suggesting that the two basins responded differently to the same climate or were influenced by contrasting climate regimes. Increases in macrocharcoal correlate with increasing pollen abundance and suggest wetter conditions. Data from the Magadi, Koora and Olorgesailie basins indicate similar trends and a dominant climate control on vegetation and habitats. Large lakes characterised all three basins at 740–528 ka with climate subsequently becoming drier, but with many wetter intervals. At various times the lakes expanded, contracted and dried out, except at Lake Magadi where spring inflows maintained lacustrine conditions through the late Quaternary. Faulting also contributed to fragmentation of the landscape and formation of a mosaic of habitats. An especially intense period of aridity at ~528–392 ka coincided with extinction of many large-bodied mammals and may have helped to drive a change from the use of Acheulean hand axes to the production of Middle Stone Age tools by 320 ka. After 200 ka pollen diversity increased substantially with a mix of montane, riparian and dry forest associations that were present in varying amounts through to ~4.2 ka at the core top.

Phylogenetic analyses indicate that the genus Podocarpus diverged around the Cretaceous/Paleogene boundary, and two monophyletic subgenera Podocarpus and Foliolatus had differentiated during the Paleogene. Most of described fossil remains were related to the subgenus Podocarpus, but those of the subgenus Foliolatus have not been well documented. Here, we described a new species of Podocarpus, P. yunnanensis sp. nov., and P. cf. forrestii from the lower Pliocene of western Yunnan, China based on a detailed comparisons of gross leaf morphology and cuticular structures between the studied fossils and extant Podocarpus. These two fossil taxa together with P. pliomacrophyllus H. Chen et J.Y. Wu from the same horizon, revealed a thriving of Podocarpus in western Yunnan during the Pliocene. For the subgenus Foliolatus, its early representatives might originate from Australasia and spread northward to northeastern India at least during the late Oligocene. The Neriifolius subclade within the subgenus is much older than the estimate of molecular clock studies, and the Indochinese subclade is probably derived from a rapid diversification driven by the continuous uplift of Hengduan Mountains (HDM) with the accompanying climate fluctuations since the late Miocene. Moreover, the thriving of Podocarpus in the Pliocene of western Yunnan reveals a warm and humid climate during that period. The Pleistocene glaciation and the geographic barriers posted by the HDM might contribute to the modern distribution of Podocarpus in South China and Indochina Peninsula.

The living species of the genus Retrophyllum C.N. Page (Podocarpaceae) are revised. A key to the six species recognised is given. Retrophyllum filicifolium (N.E.Gray) R.R.Mill comb. nov. from New Guinea and the Moluccas is recognised as a species distinct from R. vitiense (Seemann) C.N. Page, which is restricted to material from Fiji and the Solomon Islands. Additional characters are given by which to separate Retrophyllum piresii (Silba) C.N. Page (Brazil) from R. rospigliosii (Pilg.) C.N. Page (Andes). The six species fall into three species-pairs that differ in reproductive characters: one pair in Papuasia and Melanesia, a second on New Caledonia and a third in South America. In the New Caledonian species-pair, the adult leaves are flattened in four ranks with only minimal heterofacial twisting, whereas in the species-pair inhabiting Fiji, New Guinea and neighbouring areas, as well as the pair inhabiting South America, the adult leaves are arranged in two ranks with significant heterofacial twisting. The names Podocarpus filicifolius N.E.Gray and Nageia minor Carrière, respectively the basionyms of Retrophyllum filicifolium and R. minus, are lectotypified, and the typification of Nageia minor comprehensively discussed in an appendix. Adult female epitypes are additionally designated for Podocarpus filicifolius, which was originally based on juvenile foliage of Retrophyllum mixed with a detached seed of Nageia wallichiana, and for Nageia minor, which Carrière described on the basis of sterile material. Two other appendices provide a list of accepted names and synonyms, and a list of exsiccatae. Illustrations and distribution maps are provided for each species.

Sedimentos orgânicos ricos em palinomorfos, como os estudados na Vereda Juquinha/Cuba, na Serra do Cabral, no Estado de Minas Gerais, constituem um importante parâmetro para reconstituir a evolução paleoambiental. Este estudo apresenta a análise polínica qualitativa e quantitativa de 35 níveis estratigráficos de um testemunho de sondagem de 400 cm de profundidade que corresponde aos últimos ~18.500 anos cal. AP. No que diz respeito às mudanças climáticas um clima mais frio e úmido foi verificado entre ~18.500 e ~8.250 anos cal. AP e um clima mais úmido, com aumento nas temperaturas, que se iniciou a partir de ~7.800 anos cal. AP até os dias atuais. Três diferentes intervalos denominados JCI, JCII e JCIII foram estabelecidos com base nas mudanças palinológicas ao longo do testemunho de sondagem: intervalo JCI, com condições climáticas mais frias e mais úmidas que as atuais, entre ~18.500 e ~8.250 anos cal. AP, período em que foram registrados os táxons Podocarpus, Drimys brasiliensis, Eryngium, Hydrocotyle e Peperomia; intervalo JCII, de ~7.100 a ~2.900 anos cal. AP, com aumento de umidade, temperatura e diversidade de táxons e surgimento de Mauritia flexuosa a ~4.200 anos cal AP, neste intervalo a vereda tinha vegetação de entorno formada por um mosaico de Cerrado stricto sensu e Matas; intervalo JCIII, com condições de muita umidade como JCII mas com maior expansão da vereda e diminuição do mosaico de Cerrado stricto sensu e Matas da vegetação de entorno. Organic sediments rich in palynomorphs, as the ones studied in Juquinha/Cuba palm swamp, in Serra do Cabral, Minas Gerais State, can be an important proxy to reconstruct paleoenvironment evolution. This study presents the qualitative and quantitative pollen analysis of 35 stratigraphic levels from a core sample of 400 cm length corresponding to the last ~18.500 years cal. BP. Regarding to the climatic changes a colder and wetter climate was registered between ~18.500 and ~8.250 years cal. BP and a wetter climate with increase in temperatures from ~7.800 years cal. BP to the present days. Three different intervals called JCI, JCII e JCIII were established based on palynological changes along the core: interval JCI, with colder and wetter climatic conditions, between ~18.500 and ~8.250 years cal. BP recording Podocarpus, Drimys brasiliensis, Eryngium, Hydrocotyle and Peperonia taxa; interval JCII, from ~7.100 to ~2.900 years cal. BP, with the increase in humidity, temperature and taxa diversity and the first occurrence of Mauritia flexuosa at ~4.200 years cal. BP, the palm swamp in these interval was surrounded by a mosaic of Cerrado (broad sense) and forests; interval JCIII, with higher humidity conditions such as JCII conditions but with palm swamp expansion and mosaic of Cerrado (broad sense) and forests decrease.

This paper analyzes the distribution patterns of pollen and spore assemblages in modern surface sediments recovered from the bottom of the San Jorge Gulf (SJG) and from offshore sites, in relation to the location of different phytogeographic provinces surrounding the SJG, including the distant forest from southwestern Patagonia. Results reveal that pollen spectra are dominated by Chenopodiaceae-Amaranthaceae, Poaceae, Asteraceae subf. Asteroideae, Colliguaja integerrima and Ephedra sp.; which represents the vegetation adjacent to the SJG. Overall, the pollen distribution in surface sediments reflects the location of the different phytogeographic provinces and will be used as modern-analogues to document vegetation history around the SJG. Pollen assemblages also reveal the latitudinal variation of vegetation taxa in the Patagonian steppe, which is characterized by a slight increase in herbaceous pollen and a decrease in high shrubs (e.g. Colliguaja integerrima) towards the southern-central part of the SJG. Furthermore, we identified two pollen taxa from the southwestern Patagonian forest, Nothofagus and Podocarpus that could be used as indicators of past dynamics and variations of the Southern Westerly Wind Belt (SWWB) in the SJG during the Late Pleistocene and Holocene. High pollen concentrations are recorded at the central part of the SJG (480–8080 grains/g), while low concentrations are measured in the northern and southern parts of the Gulf, as well as at offshore sites (26–1806 grains/g). The pollen distribution in the study area is most likely governed by the SWWB in combination with the marine sediment composition and surface currents flowing through the SJG. Fil: Faye, Simon. Université Du Québec Á Rimouski; Canadá Fil: Rochon, André. Université Du Québec Á Rimouski; Canadá Fil: St Onge, Guillaume. Université Du Québec Á Rimouski; Canadá Fil: Vilanova, Isabel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; Argentina

Research Highlights: The study determined that selective thinning causes different responses, the initial size of the tree released is an influential factor in the growth of species. The temporality of climate and physiological conditions of each species are influential in the growth. It is evident that the defoliation of certain species is an important factor that limits the growth of the species causing thinning to have a negative response. Background and Objectives: The objective is to analyze the behavior of nine timber species, respective to diametric growth after their liberation. This research aims to answer the following questions: (i) How do the selected tree species react to the liberation? (ii) Can the productivity of the trees (diametric growth) be enhanced by liberation? (iii) Are there other factors that influence the diametric growth of the released trees? Materials and Methods: The study was executed in the “Reserva Biológica San Francisco” were 488 trees were monitored, including nine timber species. Therefore, 197 trees were released (removal of competitors) and 251 trees served as reference. To check whether the initial DBH or other factors, like the selective thinning or climate conditions, determine the diameter growth a linear mixed model GLMM was applied. To adjust the linear mixed model a one-way Anova test was executed. Results: Timber species responded differently to the thinning in comparing to reference trees. Therefore, the species analyzed were separated into three groups (positive, negative, and no response to liberation). Conclusions: Liberation potentiates the growth of certain timber species that do not defoliate and considered semi-tolerant to shade. Precipitation and temperature affect all species, but in the defoliate species, it would not be convenient to release them or at least the evidence of these first three years does not show clear differences with control trees. Increase in trees released are higher in trees of the first two diametric classes in all species, this means that larger trees (i.e., older) release does not affect them in a positive way so release should occur in the youngest trees.

The species of Podocarpus L’Hér. ex Pers. (Podocarpaceae) occurring on the islands of the Caribbean (excluding Trinidad and Tobago) are revised. Nine species are recognised, of which eight are known to be endemic to the Caribbean Bioregion. None of the species have infraspecific taxa. Four occur on Cuba, two on Hispaniola, two on Jamaica, and one on Puerto Rico and the Lesser Antilles. Keys are provided to all the species and to the species of Cuba, Hispaniola and Jamaica. The distributions of all species are mapped and discussed in relation to the geological history of the region as well as the climate, especially rainfall. The names Podocarpus urbanii Pilg. and Podocarpus buchii var. latifolius Florin are lectotypified. Revised or new IUCN conservation assessments are proposed for Podocarpus angustifolius, P. aristulatus and P. victorinianus and the existing assessments are detailed for the remaining species.

Glacial-aged vegetation dynamics of the Humaita—Western Brazilian Amazonia were studied by pollen, sedimentary facies, 14 C dating, δ 13 C org and C/N molar . Two sediment cores were taken to a depth of 10 and 8 m from areas covered by grassland and dense/open forest, respectively. The deposits represent a succession of sediment accumulation in active channel (> 42,600 cal yr B.P.), abandoned channel/floodplain (> 42,600 to ~ 39,000 cal yr B.P.), and oxbow lake sedimentary environments (~ 39,000 cal yr B.P. to modern). The predominance of mud sediments, depletion of δ 13 C org and decrease in C/N molar values identify the lake establishment. In these settings, low energy subaqueous conditions were developed, locally favoring preservation of a pollen assemblage representing herbaceous vegetation, some modern taxa from Amazonia and cold-adapted plants from the Andes represented by Alnus (2–11%), Hedyosmum (2–17%), Weinmannia (0–18%), Podocarpus (0–4%), Ilex (0–4%) and Drymis (0–1%), at least between > 42,600 and Alnus with other cold adapted plants from the Andes during the late Pleistocene indicates that Alnus probably penetrated the Western Amazonia lowland or was growing closer to the study site due to cooler temperatures during glacial times. The present study presents the first report of a glacial age forest containing Alnus in areas of the Brazilian Amazonian lowlands. In addition to its palaeogeographical importance, this work demonstrates the effectiveness of using a combination of proxies for reconstructing sedimentary environments associated with vegetation.

A palynological and sedimentological record from the Mahwaqa Mountain in KwaZulu-Natal, South Africa, provides evidence of the vegetation dynamics in this part of the Grassland Biome during the last c. 18,000 years. The wetland is located at 1,850 m on an isolated outlier of the Ukhahlamba–Drakensberg Mountain range on an ecotone along a climatic gradient. The vegetation responded to humidity and temperature changes during the late Pleistocene and Holocene. The period c. 18,000–13,500 cal. bp is characterized by high Ericaceae and Restionaceae percentages and decreasing values of charred particles, indicating cool conditions. Around 13,500–8,500 cal. bp, Ericaceae were gradually replaced by Poaceae, signaling climate warming. Growing environmental wetness during the same time period is inferred from Phragmites-type and Cliffortia pollen percentages. Since c. 8,500 cal. bp, Cliffortia, Restionaceae, and Phragmites-type percentages have maintained low levels. Ericaceae were almost completely replaced by grasses and Asteraceae by c. 7,500 cal. bp. All indications are that warm and fluctuating moisture conditions followed until 4,600 cal. bp but they became driest between c. 4,600 and 3,500 cal. bp, when high Asteraceae, Pentzia-type and Scabiosa percentages were prominent. From c. 3,500–800 cal. bp, the increase of sedges, Aponogeton and grass pollen (including Phragmites-type) at the expense of Asteraceae pollen suggests the return of slightly more humid conditions. Since c. 1,000 cal. bp an increase of water demanding Podocarpus and Cliffortia occurred. Pine pollen indicates the recent introduction of alien plants in the 19th and 20th centuries.

More than 40 years of scientific investigations of the hominin bearing Plio-Pleistocene sediments of northern Tanzania have provided a number of paleobotanical data, which, taken as a whole, provide today a way to investigate vegetation changes between 4 and 1 Ma, at a time when our early ancestors emerged. Here, I have integrated the data from all vegetation proxies obtained for the paleontological sites of Laetoli, Olduvai, and Peninj (i.e. macroscopic plant remains, pollen and phytolith assemblages, carbon and oxygen isotopic ratios measured on carbonates, and organic biomarkers). This important, yet discontinuous botanical record suggests some similarities between past and present-day vegetation at the regional scale: Afromontane forests with Olea , Podocarpus , Juniperus , Hagenia abyssinica in the highlands, and wooded grasslands with grasses and drought-adapted Acacia , Commiphora , Capparidaceae, and Chenopodiaceae and/or Amaranthaceae in the lowlands were present in the southern Serengeti–Crater Highlands region since 4 Ma. Grasses of the C 4 photosynthetic type made their first appearance in the record at ∼3.7 Ma, i.e. during the mid-Pliocene, ∼700 ky before major p CO 2 and temperature decline. C 4 grasses became dominant in the vegetation soon after (∼3.66 Ma), probably in response to reduced precipitation. At ∼2.6 Ma, phytolith and isotope indicate grassland with abundant C 4 xerophytic grasses that document strong aridity during the Intensification of Northern Hemisphere Glaciation period (∼2.7–2.5 Ma). After 2 Ma, the detailed and diverse record at Olduvai indicates complex vegetation patterns linked to oscillating precipitation, varying lake levels, and the presence of geological faults. Hence, despite low (basin-averaged) reconstructed paleo-precipitation amounts of ∼250–700 mm/y, C 4 -grasslands, closed woodlands, wetlands, and palm-groves co-occurred on short spatial scales near saline Lake Olduvai. Freshwater wetlands and palm-rich woodlands occurred in highly localized areas on the lake margins, where aquifer barriers and/or outcrops caused by geologic faults allowed groundwater discharge. Botanical evidence of paleo-springs at Laetoli, Olduvai, and Peninj includes the marked presence of Typha (cattail) and Hyphaene (palm tree) in association with Acacia pollen grains, and (at Olduvai) abundant forest indicator phytoliths and organic and isotopic biomarkers. At Olduvai, freshwater wetlands were most developed when lake level and fluvial competence where low, i.e. during dry periods. When wet–dry climate variability was extreme in East Africa (∼1.9–1.7 Ma), freshwater springs may therefore have offered a sustainable habitat (i.e. refuge) for several species, including hominins, and favored hominin and artifact concentration at these specific places, particularly during environmentally stressful times.

Inter-bedded volcanic and organic sediments from Erazo (Ecuador) indicate the presence of four different forest assemblages on the eastern Andean flank during the middle Pleistocene. Radiometric dates (40Ar-39Ar) obtained from the volcanic ash indicate that deposition occurred between 620,000 and 192,000 years ago. Examination of the organic sediment composition and the fossil pollen, wood and charcoal it contains provides insight into depositional environment, vegetation assemblage and fire history. The high organic content and abundance of macro fossils found throughout the sediment suggest that during the period of deposition the local environment was either a swamp or a shallow water body. The correlation of fire activity (peaks in charcoal abundance) with volcanic ash deposits through most of the record suggests that volcanoes were the main source of ignition. The low abundance of grass (typically < 10%) throughout the sedimentary sequence along with the low abundance of other taxa indicative of open vegetation suggests the persistence of forest at Erazo. Four types of forest assemblage were identified (with the first taxa as the most dominant): i) Alnus-Arecaceae, ii) Miconia-Melastomataceae/Combretaceae-Moraceae/Urticaceae, iii) Arecaceae-Alnus, and iv) Podocarpus with Oreopanax sp. and Melastomataceae/Combretaceae. Changes in the forest floristic composition indicate high vegetation turnover and reassortment of taxa between upper and lower montane forests during the middle Pleistocene as well as the persistence of forest cover.

There is paucity in the proxy records available for the reconstruction of vegetation and climate histories of tropical eastern Africa, especially north of the equator. Here, we present a new paleoenvironmental record based on a 3.5-m sediment core from the Kapkanyar mire, Cherangani Hills, Kenya. Using analyses of pollen, microscopic charcoal, and loss-on-ignition data, we examine the vegetation and climate history of tropical eastern Africa over the past ∼23 Kyrs. Our findings show that high levels of dry montane forest vegetation and high frequencies of Poaceae and Chenopodiaceae/Amaranthaceae (Cheno/Am) pollen types dominate the LGM period (∼23.5–18 Kyrs). The last deglaciation (∼18–12 Kyrs) is marked by a decrease in Afromontane vegetation such as Ulmaceae, Combretaceae, and Podocarpus and resurgence in Cheno/Am pollen with a minimal representation of Olea pollen. The presence of Combretaceae pollen alongside increased percentages of Cheno/Am pollen indicates that cold and dry climate likely prevailed during the last deglaciation period. The record shows that the eastern African region was generally wet over most of the Holocene, albeit with increased frequency of drought episodes. The first imprints of anthropogenic activities in the record appear between ∼4 and 3.5 Kyrs.

We present a record of environmental and climatic changes in the northern Andes during the penultimate interglacial–glacial cycle based on integrated information from pollen and grain size distributions (GSDs). The record reflects the 58.33–26.21 m interval of a new sediment core from Lake Fuquene (2540 m elevation; 5°N) in the Colombian Andes. The age model is mainly based on cyclostyratigraphy and shows that this core interval reflects the period from 284 to 130 ka. The 1 cm sample increments yield a resolution of ~ 60 yr. In 2553 samples we analyzed 66 selected pollen and spore taxa with the best known ecological ranges. We reconstructed upper forest line (UFL) positions between ~ 2000 and ~ 3400 m elevation and the most abrupt temperature shifts ranged up to 10 °C/100 yr at Terminations II and III. Regional vegetation change is mainly driven by eccentricity (100 kyr) and obliquity (41 kyr) cycles, while changes in local aquatic vegetation show variability in the obliquity and precession (21 kyr) bands. Millennial-scale climate variability reflecting Dansgaard–Oeschger (DO) climate cycles in the upper part of the record, continues in this penultimate intergalcial–glacial cycle strongly suggesting that this variability has a persistent character in Pleistocene vegetation and climate dynamics. Short-lived upslope excursions of the UFL reflect 20 DO-style cycles during marine isotope stages (MIS) 7 and 6. Changes in species composition of montane forest are evident, and trees with most pioneer qualities ( Alnus , Morella , Quercus and Weinmannia ) migrated at the forefront. Other arboreal taxa like Podocarpus , Miconia , and Hedyosmum mostly followed later. Changes in regional vegetation distribution and forest composition, as well as in local aquatic vegetation and GSD of sediments supplied to the lake, allowed the development of an integrated reconstruction of the biotic and abiotic environments in the drainage basin.

International audience; Despite the southern Cape's great climatic and botanical significance (occupying the transition between the temperate and subtropical circulation systems and forming part of a global biodiversity hotspot), palaeoenvironmental data for this region of southern Africa is limited. This study presents pollen, charcoal and sedimentological data preserved in the Vankervelsvlei wetland, situated in the modern year-round rainfall zone at the ecotone between the Fynbos and Afrotemperate Forest biomes. Combining optically stimulated luminescence and radiocarbon dating techniques, it was possible to establish a chronology for a sediment sequence spanning the last 140,000 years, the longest record yet produced in the region. The data suggest that MIS 5d was relatively warmer (low fynbos pollen percentages and Pentzia-type pollen) than later MIS 5, MIS 4 and most of MIS 3 (~96e37 ka), which were characterised by decreased temperatures (dominance of ericaceous fynbos). The pollen data indicate a complex response to the change from interglacial to glacial conditions, and suggest an important threshold is crossed in regional ecological dynamics. We postulate that during MIS 5d increased summer rainfall under warmer conditions may have offset increased potential evapotranspiration, allowing for the development of more extensive forests. During its early stages of development Vankervelsvlei was more open (increased aquatics and coarse sediment), trapping more longer-distance pollen (Podocarpus). As the mire became more closed, local elements dominated; a succession that is reflected in significant changes in the pollen assemblage, as Podocarpus remains only in trace percentages, but pollen of Can-thium and Morella, which occupy nearly identical climatic niches as Podocarpus, increase in abundance. It is suggested that drought stress remains limited during the last glacial period as a result of reduced temperatures, compensating for what may have been a more seasonal winter-dominated rainfall regime, and that changes in the pollen record relate to vegetation succession and the development of the wetland rather than to major changes in moisture availability. Due to the virtual absence of palaeodata from the southern Cape covering MIS 5 to MIS 3, the establishment of this record provides an important contribution to the overall palaeoenvironmental history of the region.

Little is known about the southernmost occurrence of small areas with Araucaria angustifolia populations in Caçapava do Sul in low elevated areas of Rio Grande do Sul State, about 130 km to the south of to the highlands of southern Brazil where the main distribution of Araucaria is found. This occurrence is about 130 km further south to the main area of Araucaria angustifolia which is on the highlands in southern Brazil. The question is whether this occurrence is natural, due to indigenous peoples, or due to plantation by post-Columbian settlers. To trace the origin of this little known southernmost existence of Araucaria angustifolia trees is of particular interest for conservation issues. To address this question we did a vegetation survey and studied a 150 cm-long radiocarbon dated sediment core from the Fazenda da Mônica by pollen analysis. The vegetation survey of the study area indicates that also other typical taxa of the Araucaria forest as well as the Atlantic lowland rainforest are found in the present-day semi-deciduous forest, such as Podocarpus, Ilex, Myrsine and Prunus for the former, and Alchornea, Moraceae, Arecaceae, and Myrtaceae for the later. The pollen record, due to bad pollen preservation, starts only after 44 cm core depth, which is about 515 cal yr BP old (AD 1490), indicating that Araucaria angustifolia as well as other Araucaria forest and Atlantic rainforest taxa occurred in this area since the beginning of the pollen record. The occurrence of these taxa can be seen as natural and not introduced during the post-Columbian colonisation. First settlers at the beginning of the 19th century reduced existing population of Araucaria markedly and in particular since about AD 1950. The population of Araucaria angustilfolia before the post-Columbian settlement was much larger than today. peerReviewed

This paper presents the late Holocene vegetation and fire history record from Parque Provincial Cruce Caballero, Misiones, NE Argentina (26° 30′ 55.35″ S, 53° 59′ 44.73″ W). The pollen and charcoal content of the 194 cm deep sediment core dating to ca. 1840 cal yr BP permitted the recognition of three distinct zones. Zone CC - 1 (before ca. 1810 cal yr BP) was characterised by a forest dominated by Myrtaceae that also included other forest taxa like Alchornea , Trema and Moraceae/Urticaceae. The presence of Zea mays (maize) pollen grains around 1840 cal yr BP suggests the presence of pre-Colombian groups in the region who practiced food-production. Zone CC - 2 (ca. 1810 to ca. 40 cal yr BP) witnessed the establishment of an herbaceous wetland in the locality as evidenced by the formation of peat and the increase in wetland taxa, in particular the Cyperaceae, indicating the change to a wetter and less seasonal climate that appears to be coeval with pollen records and soil-depth profiles' carbon isotope records documented in other regions of the southern Brazilian highlands during the late Holocene. The basal section of this zone also documents the arrival of Araucaria angustifolia trees to the region, the presence of maize, and a moderate increase in fires that could be related to more intense human activity in the region. The upper section of this zone shows a slight increase in A. angustifolia paralleled by a raise of other typical elements of mixed Araucaria forests like Clethra , Ilex , Myrsine and Podocarpus . Zone CC - 3 (ca. 40 cal yr BP–today) shows a major increase in trees and ferns (particularly Osmunda ) at the expense of sedges and grasses evidencing a local change from a wetland dominated herbaceous vegetation to the one dominated by arboreal taxa and ferns that exists today. This zone also shows a reduction in regional fires and the disappearance of local fires that seems to be associated to the creation of the Parque Provincial Cruce Caballero. Poaceae pollen percentages remained relatively low throughout the sequence indicating that the region did not support Campos (grassland) vegetation but was a forested landscape during the late Holocene.

The paleoecology of tropical Podocarpaceae is reviewed for Africa and Southeast Asia. The family first appeared in the Triassic of Gondwana, after which it diversified through the Cretaceous and earliest Tertiary, and although some Northern Hemisphere Jurassic records are known, it has essentially remained a southern or southern-derived family until the present day. It seems to show a preference for areas of wet climate throughout its history. Podocarpus sensu lato dispersed into Southeast Asia during the late Eocene, and its present distribution is best explained by dispersal from India and possibly multiple long-distance dispersal events from Australia. Dacrydium reached Southeast Asia during the early Oligocene, presumably by island hopping, via the Ninety East Ridge and India and subsequently expanded its range to Japan during the middle Miocene climatic optimum. It is likely that the dispersal pathway was via low-altitude heath forests. Dacrycarpus and Phyllocladus dispersed into New Guinea as the island became established during the late Miocene and then island hopped to Borneo during the mid-Pliocene. Dacrycarpus subsequently reached Sumatra and the Malay Peninsula during the Pleistocene. In Africa, Podocarpus sensu lato was probably present in upland areas during the mid-Tertiary but dispersed by island hopping between montane areas to West Africa in the late Pliocene. In both Africa and Southeast Asia, the Podocarpaceae have clearly increased their range within the low latitudes following mid-Pliocene global climate deterioration and the Northern Hemisphere ice expansion.

Dinoflagellate cysts, pollen and charred cuticle fragments from two sediment cores (giant piston Calypso core MD03-2708 and giant gravity Casq core MD03-2708CQ) collected off the Ogooue River mouth, Gabon (01°10.33′S–08°19.01′E, 920 m water depth) have been analysed to identify the direction and timing of marine–terrestrial environmental changes over western equatorial Africa during the last 26,000 yr. Changes in the proxy records indicate that both terrestrial and oceanic domains off Gabon were impacted synchronously by significant climate changes during the last glacial–interglacial transition and Holocene. Leading into, and during, the Last Glacial Maximum (LGM), heterotrophic dinoflagellate cysts and Ca X-ray fluorescence intensity suggest nutrient enrichment off the river mouth, while pollen records indicate expansions of open forest, savannah woodland, and the Afromontane forest in the catchment area. From the deglaciation to mid-Holocene, however, a marked decrease in Brigantedinium spp. as well as in Poaceae, Cyperaceae and Podocarpus pollen reflects a reduction in nutrient supply to the coastal ocean in parallel with a reduction in grassland, herbaceous communities and Afromontane forest within the catchment. A sharp decline or even disappearance of heterotrophic species during this period is almost contemporaneous with an appearance of Operculodinium aguinawense , reflecting enhanced river influence in the study area. A marked increase of Rhizophora (mangrove) pollen during this transition also indicates eustatic sea-level rise after the LGM which forced a major expansion of the mangrove ecosystem across the gradually submerging shelf. The combination during the late Holocene of a reoccurrence of heterotrophic dinoflagellate cysts with increased Poaceae, Cyperaceae and Podocarpus pollen indicates enhanced nutrient supply to the ocean concordant with a shift to cooler/drier conditions over the Gabon basin. This appears to be linked to a deterioration of the monsoon system induced by the low sea-surface temperatures in the tropical Atlantic Ocean in association with decreased summer insolation.

article i nfo Article history: Pollen analysis of soils overlain by welded tuffs of the Yellowstone hotspot provides a radiometrically-dated chronology of the vegetation 12-7 Ma for central Snake River Plain. The welded tuffs, produced as the Yellowstone hotspot migrated eastward, overlie soils containing perfectly-preserved pollen, occasionally containing cytoplasm. The pollen assemblage is dominated by Artemisia (sagebrush; ave. 32%, range 11-61%) and Poaceae (grass; ave. 21.3%, range 4-55%). This assemblage is very similar to that found in the area today, except the welded-tuff samples contain low percentages (b5%) of arboreal taxa not found in the current flora: Podocarpus, Cedrus, Taxus, Aesculus, and Ulmus. The values of Artemisia and Poaceae are much higher than those found in samples of the same age (12-7 Ma) from the Pacific Northwest (which are dominated by tree pollen) and the Great Salt Lake basin (which are dominated by pine (Pinus), and greasewood (Sarcobatus)). Furthermore, the welded-tuff samples from the Snake River Plain contain a diverse herbaceous taxa characteristic of modern sagebrush steppe, and a diverse fungal spore assemblage including the root symbiont Glomus and the dung fungus Sporormiella. These results show that sagebrush steppe was widespread on the western Snake River Plain 12 Ma, at least 5 Ma earlier than previously recognized. © 2010 Published by Elsevier B.V.

Fossils of forest habitat beetles and leaves of Nothofagus menziesii provide evidence of a forest refugium at times between ca. 34 000 and ca. 18 500 cal. a BP at an upland site in Howard Valley, located adjacent to glaciated valleys in South Island, New Zealand. The stratigraphy of the glacial-aged terrace sequence of organic-rich silts and fluvial sand/gravels indicates that soil development occurred episodically for around 15 000 a. Fifty-four beetle taxa represent seven habitat types: forest, forest or scrub, riparian and aquatic, litter, grass/tussock, marshland and moss habitats. Leaf and beetle fossils indicate that forest dominated by N. menziesii persisted at the site for most of the time period represented, and tree line taxa such as Taenarthrus sp. 1 (Carabidae) and Podocarpus sp. (Podocarpaceae) indicate that the site may represent the upper tree limit for full-glacial time. The finding of forest at this elevated site adds to the growing fossil evidence for multiple forest refugia in New Zealand during the last glaciation and is consistent with the pollen records, which have consistently indicated the presence of forest species during the last glaciations. Copyright © 2009 John Wiley & Sons, Ltd.

Throughout the tropics, processes of ecological degradation, land-use change, deforestation, and frontier expansion have been linked to roads. Roads, and the access they give people, are correlated...

Two new species, Macrocarpaea claireae and M. quizhpei (Gentianaceae: Helieae), are described from the Huancabamba region of southern Ecuador. Macrocarpaea claireae occurs around Valladolid, adjacent to P. N. Podocarpus, and M. quizhpei occurs in the Nangaritza watershed. M. claireae is closely related to M. pringleana and M. sodiroana, yet differs notably in its glaucous-green, campanulate-urceolate calyx. Macrocarpaea quizhpei has affinities to M. dies-viridis, but differs in having a large, diffusely branched, open thyrse to 1.3 m high.

This paper documents a continuous ∼ 44,000-yr pollen record derived from the Mfabeni Peatland on the Maputaland Coastal Plain. A detailed fossil pollen analysis indicates the existence of extensive Podocarpus-abundant coastal forests before ∼ 33,000 cal yr BP. The onset of wetter local conditions after this time is inferred from forest retreat and the development of swampy conditions. Conditions during the last glacial maximum (∼ 21,000 cal yr BP) are inferred to have been colder and drier than the present, as evidenced by forest retreat and replacement of swampy reed/sedge communities by dry grassland. Forest growth and expansion during the Holocene Altithermal (∼ 8000–6000 cal yr BP) indicates warm, relatively moist conditions. Previous records from Maputaland have suggested a northward migration of Podocarpus forest during the late Holocene. However, we interpret a mid-Holocene decline in Podocarpus at Mfabeni as evidence of deforestation. Forest clearance during the mid-Holocene is supported by the appearance of Morella serrata, suggesting a shift towards more open grassland/savanna, possibly due to burning. These signals of human impact are coupled with an increase in Acacia, indicative of the development of secondary forest and hence disturbance.

The Huancabamba Biogeographical Province covers sections of southern Ecuador and northern Peru, and is well known for both its biodiversity and high levels of endemism. Paramo, a form of tropical alpine vegetation, covers less area in this region than in other tropical montane regions, and is dominated by shrubs instead of tussock grasses. A botanical inventory was conducted at a paramo site in Podocarpus National Park, southern Ecuador. Located between 3385 and 3250 m elevation, this site covers 2.4 ha of grass- and shrub-dominated vegetation communities. Fifty-five families, 90 genera and 136 species occurred, 27 of which are endemic to Ecuador. Both the combination of species and the growth forms differ markedly from those of most other paramo ecosystems. After describing the floristic characteristics of the site, I discuss the species composition, growth forms, and patterns of endemism in relation to various geographical and ecological factors.

Pollen, spore, macrofossil and stable isotope (C and N) analyses from a 266-cm sediment core collected from a swamp on the Eastern Arc Mountains, Tanzania, are used to reconstruct vegetation and environmental history. An estimated time scale based on five14C ages records approximately 38,000 yr. This palaeorecord is the first from this biodiversity hotspot and importantly extends through the last glacial maximum (LGM). The altitudinal transition from montane to upper montane forest shifted from 1700–1800 m (38,00014C yr BP) to 1800–1900 m (35,000–29,00014C yr BP). From 29,000 to 10,00014C yr BP, it shifted from 1850–1950 m across the LGM to 1750–1800 m (during 10,000–350014C yr BP), and to present-day elevations at 2000 m during the last 350014C yr BP. The relative ecosystem stability across the LGM may be explained by the Indian Ocean's influence in maintaining continuous moist forest cover during a period of East African regional climate aridity. During the late Holocene, presence of abundant coprophilous fungi and algal blooms demonstrates increasing human impact.Neurospora spores indicate frequent fires, coinciding with clear signals of decline inPodocarpus and Psychotria trees that possibly represent selective logging.

The potential to provide environmental proxies using stable carbon isotopes from modern and archaeological charcoal is explored. Experiments on modern Podocarpus (Yellowwoods) show that δ 13 C values of stems, branches and charcoal preserve proxy environmental conditions, including rainfall, humidity and temperature. An additional experiment showed that combustion temperature affects the carbon isotope signature of charcoal. Burning at 450 °C to 500 °C depletes δ 13 C values with respect to the original wood, but the charcoal retains the seasonal and inter-annual isotopic trends recorded during the growth of the tree. The δ 13 C of Podocarpus charcoal from three levels from the Middle Stone Age site of Sibudu Cave, KwaZulu-Natal, South Africa, was compared with modern analogues from two different environments, Seaton Park (KwaZulu-Natal) and the Baviaans Kloof (Eastern Cape). Other environmental proxies from levels dated from > 70 ka and ~ 48 ka, show that environmental conditions changed from warmer and wetter to colder and drier and finally becoming warmer and drier. The isotope data is consistent with this reconstruction. The results from this series of experiments indicate that it is possible to obtain meaningful palaeoenvironmental information from δ 13 C values of archaeological charcoal.

In order to study the stability and dynamics of mountain rainforest and paramo ecosystems, including the biodiversity of these ecosystems, the Holocene and late Pleistocene climate and fire variability, and human impact in the southeastern Ecuadorian Andes, we present a high-resolution pollen record from El Tiro Pass (2810 m elevation), Podocarpus National Park. Palaeoenvironmental changes, investigated by pollen, spores and charcoal analysis, inferred from a 127 cm long core spanning the last ca. 21 000 cal. yr BP, indicate that grass-paramo was the main vegetation type at the El Tiro Pass during the late Pleistocene period. The grass-paramo was rich in Poaceae, Plantago rigida and Plantago australis, reflecting cold and moist climatic conditions. During the early Holocene, from 11 200 to 8900 cal. yr BP, subparamo and upper mountain rainforest vegetation expanded slightly, indicating a slow warming of climatic conditions during this period. From 8900 to 3300 cal. yr BP an upper mountain rainforest developed at the study site, indicated by an increase in Hedyosmun, Podocarpaceae, Myrsine and Ilex. This suggests a warmer climate than the present day at this elevation. The modern subparamo vegetation became established since 3300 cal. yr BP at El Tiro Pass. Fires, probably anthropogenic origin, were very rare during the late Pleistocene but became frequent after 8000 cal. yr BP. Copyright # 2007 John Wiley & Sons, Ltd.