The main phases of plant dispersal into, and out of the South-East Asian region are discussed in relation to plate tectonics and changing climates. The South-East Asian area was a backwater of angiosperm evolution until the collision of the Indian Plate with Asia during the early Cenozoic. The Late Cretaceous remains poorly understood, but the Paleocene topography was mountainous, and the climate was probably seasonally dry, with the result that frost-tolerant conifers were common in upland areas and a low-diversity East Asian aspect flora occurred at low altitudes. India's drift into the perhumid low latitudes during the Eocene brought opportunities for the dispersal into South-East Asia of diverse groups of megathermal angiosperms which originated in West Gondwana. They successfully dispersed and became established across the South-East Asian region, initially carried by wind or birds, beginning at about 49 Ma, and with a terrestrial connection after about 41 Ma. Many Paleocene lineages probably went extinct, but a few dispersed in the opposite direction into India. The Oligocene was a time of seasonally dry climates except along the eastern and southern seaboard of Sundaland, but with the collision of the Australian Plate with Sunda at the end of the Oligocene widespread perhumid conditions became established across the region. The uplift of the Himalaya, coinciding with the middle Miocene thermal maximum, created opportunities for South-East Asian evergreen taxa to disperse into north India, and then with the late Miocene strengthening of the Indian monsoon, seasonally dry conditions expanded across India and Indochina, resulting eventually in the disappearance of closed forest over much of the Indian peninsula. This drying affected Sunda, but it is thought unlikely that a ‘savanna’ corridor was present across Sunda during the Pleistocene. Some dispersals from Australasia occurred following its collision with Sunda and following the uplift of New Guinea and the islands of Wallacea, Gondwanan montane taxa also found their way into the region. Phases of uplift across the Sunda region created opportunities for allopatric speciation and further dispersal opportunities. There is abundant evidence to suggest that the Pleistocene refuge theory applies to the South-East Asian region.

Seed dispersal effectiveness (SDE) is related to the role of seed dispersal agents in realizing the reproductive potential of plants through seed dispersal and subsequent plant recruitment. The SDE of a given seed disperser may vary spatially and temporally, with important implications for our understanding of the mutualistic relationships involving plants and frugivores. Here we observed 22 frugivorous bird species visiting an individual tree (Cabralea canjerana) over a 9-y period in a fragment of Atlantic forest in south-eastern Brazil to document the temporal variation in SDE. The quantitative (that takes into account the frequency of feeding visits to the focal plant and the number of fruits removed per visit) and qualitative (that considers the probability of seed deposition on a suitable site for plant recruitment) components of SDE varied in two and one order of magnitude both among bird species and among years within bird species, respectively. As a result, the SDE of bird species fluctuates over the years, especially for a migratory species that is the main seed disperser of C. canjerana (Chivi vireo Vireo chivi) whose quantitative component (i.e. the product of visit and fruit intake rates) varied from 3.0 to 7.1. This study illustrates the dynamic nature of the seed-dispersal environment to which a plant is subjected to over the course of its life, which has important consequences for the plant's individual fitness.

Forest fires pose an important threat to tropical rain-forest biodiversity. In the present study, we assessed ground layer (herb and shrub) communities in six differentially disturbed landscape plots in East Kalimantan, Indonesia, including primary and logged forest and once-, twice- and frequently-burnt forest. Overall, we recorded 175 species of herbs and shrubs; richness was highest in twice-burnt forest and lowest in logged forest. Vegetation and topographical variables including the percentage of the plot burnt and tree abundance were significant predictors of variation in composition. The main compositional gradient showed a clear distinction between subplots in unburnt versus burnt forest. A subset of subplots in burnt forest, however, clustered together with subplots from unburnt forest. These plots were located in a network of relatively unscathed forest along floodplains that persisted in the burnt-forest matrix. Small plant species associated with unburnt forest included several species of Dryopteridaceae, Marantaceae and Rubiaceae. Species associated with once- and twice-burnt forest included Mikania scandens (Compositae), Microlepia speluncae (Dennstaedtiaceae), Nephrolepis cf. biserrata (Nephrolepidaceae), Lygodium microphyllum (Schizaeaceae) and Hornstedtia cf. reticulata (Zingiberaceae). The frequently-burnt landscape plot was characterized by a high cover of the grass species Imperata cylindrica and the invasive exotic shrub Chromolaena odorata. Importantly, these species and other exotics had also invaded the once- and twice-burnt forest and represent a potential threat to forest recovery.

Liana abundance and size have increased in neotropical forests. High vegetative reproductive capacity (clonality) may be the cause of high abundance in some liana species. Correlations between vegetative propagation capacity and (1) relative abundance of liana species, (2) rooting and foliar sprouting potentials of congeneric species, and (3) phylogenetic position were determined. Species selection was based on the relative abundance of lianas in ten 0.5-ha parcels in continuous forest within the Biological Dynamics of Forest Fragments Project (BDFFP), Brazil. Five individuals per species were replicated with seven cuttings per individual. Cuttings placed in moistened sand and coconut fibre were observed for 5 mo in a humid greenhouse. Survival percentage, rooting percentage, potential regeneration index and longest root length were determined per species. The two most abundant species (9.3% and 4.1% relative abundance) had low vegetative regeneration capacity, contrary to expectations. However, a significant, positive relationship between vegetative propagation and relative abundance of liana species whose relative abundances were <4% was found. Congeneric species showed no difference in vegetative propagation between rare and abundant species, except congeners of Machaerium. Vegetative reproductive capacity occurred in all major evolutionary lineages, but was highest in Fabaceae and Bignoniaceae, families of high abundance both locally and broadly across Neotropical forests.

The variation in CO2 flux from the forest floor is important in understanding the role of mangrove forests as a carbon sink. To clarify the effects of soil temperature and tidal conditions on variation in CO2 flux, sediment–atmosphere CO2 fluxes were measured between June 2012 and May 2013. We used the closed chamber method for two plots, with a 0.5 m difference in elevation (B, high elevation; R-B, low elevation), in a mangrove forest in south-western Japan. CO2 fluxes were highest in the warm season and showed a weak positive correlation with soil temperature in both forests. Estimated monthly CO2 flux showed moderate seasonal variation in accordance with the exposure duration of the soil surface under tidal fluctuation. Additionally, measured CO2 flux and soil temperature were slightly higher in the R-B plot than the B plot, although estimated annual CO2 flux was higher in the B plot than the R-B plot due to different exposure durations. These results suggest that variation in the exposure duration of the forest floor, which changes seasonally and microgeographically, is important in evaluating the annual CO2 flux at a local scale and understanding the role of mangrove ecosystems as regulators of atmospheric CO2.