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Identifying physical and ecological boundaries that limit where species can occur is important for predicting how those species will respond to global change. The island of Borneo encompasses a wide range of habitats that support some of the highest richness on Earth, making it an ideal location for investigating ecological mechanisms underlying broad patterns of species distribution. We tested variation in richness and range‐size in relation to edaphic specialization and vegetation zone boundaries using 3060 plant species from 193 families centered around the elevational gradient of Mt Kinabalu, Borneo. Across species, average range‐size increased with elevation, consistent with Rapoport's rule. However, plants associated with ultramafic soil, which is low in nutrient and water availability and often has high concentrations of heavy metals, had larger range‐sizes and greater richness than expected along the elevational gradient, as compared to a null model with randomization of edaphic association. In contrast, non‐ultramafic species had smaller range‐sizes and lower richness than expected. These results suggest that tolerance of resource limitation may be associated with wider range‐sizes, whereas species intolerant of edaphic stress may have narrower range‐sizes, possibly owing to more intense competition in favorable soil types. Using elevation as a predictor of average range‐sizes, we found that piece‐wise models with breakpoints at vegetation zone transitions explained species distributions better than models that did not incorporate ecological boundaries. The greatest relative increases in range‐size with respect to elevation occurred mid‐elevation, within the montane cloud forest vegetation zone. Expansion of average range‐size across an area without physical boundaries may indicate a shift in ecological strategy and importance of biotic versus abiotic stressors. Our results indicate that elevational range‐size patterns are structured by ecological constraints such as species' edaphic association, which may limit the ability of species to migrate up or down mountains in response to climate change. [ABSTRACT FROM AUTHOR]

Background and aims: Pioneer plants may improve the ecological restoration of degraded ultramafic areas by plant-soil interaction processes. In this study, we assess the effect of the pioneer actinorhizal tree C. terminale (Casuarinaceae) on the recovery of plant communities and soil functions on degraded tropical ultramafic sites. Methods: Soil and plant samples were collected along a tree-age gradient in two degraded ultramafic sites in Sabah (Northern Borneo, Malaysia): a Technosol and a Leptosol. Chemical composition of plants and soils, and biological activity of soils were assessed at both sites. Plant colonisation was assessed by plot vegetation surveys. Results: An improvement in soil fertility parameters (pH reduction from 8.5 to 6.8, an increase in the concentrations of several nutrients and enhanced soil enzyme activities) was observed along the C. terminale age gradient. However, plant cover and diversity was only improved around mature trees at the site that was not impacted by mining. Conclusion: C. terminale promotes the recovery of several soil functions, mainly related to the storage and recycling of N, P, K, S. Besides plant-soil feedback, other environmental factors (i.e. exposition to sunlight, drought) may play an important role on revegetation of ultramafic soils. [ABSTRACT FROM AUTHOR]

The Sunda Pangolin Manis javanica is naturally present in Gaya Island, Sabah, but its population status is largely unknown. Results from a recent survey using camera traps indicated the presence of a few individuals, who were strictly nocturnal. There is a strong indication that the population in Gaya Island is in danger of local extinction. There is also an urgent need to conduct an in-depth study to gather scientific information for further conservation action. [ABSTRACT FROM AUTHOR]

The foliar elemental profile of most plants reflects that of the soil on which plants grow in their natural habitat. The aim of this study was to elucidate foliar elemental profiles in the ultramafic flora of Kinabalu Park in Sabah, Malaysia. Kinabalu Park is ideal for studying plant elemental profiles because of its exceptionally rich flora and diversity in soil types. Foliar elemental profiles of 594 plant species in 99 families were analysed (totalling 1710 samples). This included 495 species (90 families) from ultramafic soils, and 120 species (45 families) from non-ultramafic soils (used as a comparison dataset). In general, the foliar elemental uptake ranges from exclusion of phytotoxic elements such as Ni and Mn, to a limited number of plant species characterised by extreme accumulation of specific elements, including trace elements (Co, Mn, Ni, Zn,), or non-essential elements (Al). This research identified hyperaccumulator behaviour (as defined by exceedances of established threshold foliar concentrations) in numerous plant species: Al > 1000 μg g−1 (38 spp.), Mn > 10 mg g−1 (7 spp.), Co > 300 μg g−1 (3 spp.), Ni > 1000 μg g−1 (24 spp.) and Zn > 3000 μg g−1 (2 spp.). Distinct phylogenetic patterns emerged for Ni in which 18 of the identified 24 Ni hyperaccumulators were in the order Malpighiales, predominantly in the families Phyllanthaceae, Salicaceae and Violaceae. [ABSTRACT FROM AUTHOR]

Aim Adult survival is central to theories explaining latitudinal gradients in life history strategies. Life history theory predicts higher adult survival in tropical than north temperate regions given lower fecundity and parental effort. Early studies were consistent with this prediction, but standard-effort netting studies in recent decades suggested that apparent survival rates in temperate and tropical regions strongly overlap. Such results do not fit with life history theory. Targeted marking and resighting of breeding adults yielded higher survival estimates in the tropics, but this approach is thought to overestimate survival because it does not sample social and age classes with lower survival. We compared the effect of field methods on tropical survival estimates and their relationships with life history traits. Location Sabah, Malaysian Borneo. Time period 2008-2016. Major taxon Passeriformes. Methods We used standard-effort netting and resighted individuals of all social and age classes of 18 tropical songbird species over 8 years. We compared apparent survival estimates between these two field methods with differing analytical approaches. Results Estimated detection and apparent survival probabilities from standard-effort netting were similar to those from other tropical studies that used standard-effort netting. Resighting data verified that a high proportion of individuals that were never recaptured in standard-effort netting remained in the study area, and many were observed breeding. Across all analytical approaches, addition of resighting yielded substantially higher survival estimates than did standard-effort netting alone. These apparent survival estimates were higher than for temperate zone species, consistent with latitudinal differences in life histories. Moreover, apparent survival estimates from addition of resighting, but not from standard-effort netting alone, were correlated with parental effort as measured by egg temperature across species. Main conclusions Inclusion of resighting showed that standard-effort netting alone can negatively bias apparent survival estimates and obscure life history relationships across latitudes and among tropical species. [ABSTRACT FROM AUTHOR]

We investigated consequences of plant-soil feedbacks (PSFs) in a tropical montane forest on Mt. Kinabalu in Borneo by measurements of light and soil conditions, ecophysiological analyses of tree seedlings, a long-term adult and seedling census, and a simple simulation model. The study plot (2.74 ha) is in a mixed conifer-broadleaf forest with 24% relative basal area of conifers. First, we investigated light and soil conditions beneath two dominant species, a conifer Dacrydium gracilis (Podocarpaceae, arbuscular mycorrhizal tree) and a broadleaf Lithocaprus clementianus (Fagaceae, ectomycorrhizal tree). The relative light intensity was marginally higher beneath Dacrydium tree crown than beneath Lithocarpus tree crown. The concentrations of inorganic nitrogen and labile phosphorus, and the nitrogen mineralization rate, were lower beneath Dacrydium than beneath Lithocarpus, suggesting that soils beneath Dacrydium were more nutrient deficient. Microscopic observations confirmed that conifer seedlings (including Dacrydium) harbored arbuscular mycorrhizal fungi. In addition, a molecular analysis showed that root-associated mycorrhizal fungal communities were clearly different between conifer and broadleaf seedlings, and consequently, nutrient acquisition capacity of seedlings may be different between them. Indeed, stable isotopic evidence suggested that Dacrydium seedlings are more efficient in inorganic nitrogen acquisition than Lithocarpus seedlings. These results predicted that the conifer seedlings would out-compete broadleaf seedlings and have a greater advantage beneath the conifer canopy. To test the possible advantage of conifer seedlings in performance, we developed hierarchical Bayesian models and estimated growth and mortality rates using the seedling census data during 2006-2012. We found that conifer seedlings performed better than broadleaf seedlings beneath Dacrydium canopy. On the other hand, broadleaf seedlings performed better than conifer seedlings beneath Lithocarpus canopy. The consequences of the PSFs for the tree community composition were investigated by developing a simple simulation model, and were compared with the results of a model without PSFs. After a 10 000-year simulation, the relative abundance of conifers with PSFs converged to 22%, which was consistent with the actual abundance; the model without effects of PSFs predicted a relative abundance of only ~10%. The results suggested that PSFs contributed to the maintenance of the conifer dominance in the tropical montane forest. [ABSTRACT FROM AUTHOR]

Background and aims: Kinabalu Park is the world's most species-rich hotspot with over 5000 plant species recorded for an area 1200 km. The aim of this study was to characterise the vegetation on ultramafic edaphic 'islands' in relation to soil chemistry and elevation. Methods: In total 87 non-permanent vegetation plots were established covering 12 ultramafic edaphic 'islands' from 474 to 2950 m asl in which 2854 plant species in 742 genera and 188 families were recorded from 14 662 collections. Results: The results show that plant diversity decreases with elevation, but a mid-elevation (circum 1500 m asl) 'hump' occurs for some plant groups (orchids, pteridophytes) as a result of the presence of cloud forests. Six main vegetation classes with associated soil types were discerned: (i) Sub-Alpine Scrub; and (ii) Graminoid Scrub, both associated with Hypermagnesic Cambisols ('hypermagnesian soils'); (iii) Montane Cloud Forest, associated with Cambisols often with accumulation of humus; (iv) Mixed Dipterocarp Forest, associated with deep Ferralsols ('laterites'); (v) Pioneer Casuarina Scrub; (vi) Mature Mixed Casuarina Forest, both associated with Hypermagnesic Leptosols. Conclusions: We hypothesised that 'adverse' soil chemistry would exacerbate vegetation stunting, and the results confirmed that stunted vegetation and elevational floristic compression occurs on chemically adverse soils (mainly hypermagnesian soils). However, no clear correlation with plant diversity was found, as some of the most 'adverse' soils on the summit of Mount Tambuyukon had up to 132 species per 250 m. [ABSTRACT FROM AUTHOR]

Ultramafic outcrops occupy less than 1% of the land surface of the Earth and are renowned as hotspots of plant diversity and endemism. With over 3500 km² of ultramafic outcrops in Sabah (4.6% of the total landmass of the state) on the island of Borneo and a total of 4252 plant species recorded occurring on this substrate, Malaysia has one of the most species-rich floras occupying these outcrops globally. Over 2542 plant species have been documented on ultramafic outcrops in Kinabalu Park alone, of which a large percentage is endemic to either Kinabalu Park or Borneo. Despite the existence of this species rich flora, the full plant diversity and ecology remains largely unknown because of a lack of focussed research. Furthermore, plant diversity in many areas of Sabah is severely threatened by land-use conversion and, because many plant species occur only in a single or a few ultramafic sites, impacts on the ecosystems that support them could eventually result in their extinction. Sabah (Malaysia) has some of the largest ultramafic outcrops on Earth and host at least 4252 plant species. The full plant diversity is yet unknown because of a lack of research, while this flora is also threatened by land-use conversion. [ABSTRACT FROM AUTHOR]

We describe here the structure, floristics and diversity of tropical montane rain forests over ultramafic soils on Mount Kinabalu, Borneo, and compared them with those on non-ultramafic soils. We used 14 sample plots from 1580 to 3080 m elevation, six on ultramafic soils and eight on non-ultramafic soils, and identified all trees ≥4.8 cm diameter. The plot area ranged from 0.1 to 1 ha, the majority (nine plots) being 0.25 ha. Forests on ultramafic soils showed more stunted structure, especially at higher altitudes, than those on non-ultramafic soils and on ridges than on slopes. Species of Coniferae (Araucariaceae and Podocarpaceae) and Myrtaceae strongly dominated on ultramafic soils occupying 61-96% of basal area in each plot, compared with 22-63% on non-ultramafic soils. Among 287 species found in the 14 plots, only nine species (including four species endemic to Mount Kinabalu) were strictly restricted to ultramafic soils. Nonmetric multidimensional scaling demonstrated that elevational change in species composition was accelerated on ultramafic soils and on ridges. Tree species diversity was generally lower on ultramafic soils than on non-ultramafic soils at the comparative altitudes. Multiple regression analysis suggested that soil nutrients (phosphorus and nitrogen) could be the cause of vegetation differentiation between ultramafic and non-ultramafic soils, although the data on soil metals are lacking. Comparison of our results with those from other mountains with ultramafic soils in South-east Asia demonstrated the uniqueness of the montane rain forests over ultramafic soils on Mount Kinabalu. Mount Kinabalu, Borneo, with the summit elevation of 4095 m and diverse geology, is one of the global centres of plant diversity. By using vegetation sample plots, we compared the tropical montane rain forests over ultramafic soils with those over non-ultramafic soils on Mount Kinabalu, and also with those on other mountains with ultramafic soils in South-east Asia. The results demonstrated the uniqueness of the ultramafic vegetation on Mount Kinabalu. [ABSTRACT FROM AUTHOR]

To understand the variation in community dynamics of tropical montane forests along gradients of soil fertility, death, recruitment and growth of trees (≥5 cm diameter) were monitored over 14 y (1997–2011) in nine plots placed in a matrix of three geological substrate types (Quaternary sediments, Tertiary sedimentary rocks and ultrabasic rocks) and three topographical units (ridge, middle and lower slopes) on Mount Kinabalu, Borneo. The plot area was 0.05 ha for ridge, 0.1 ha for middle slope and 0.2 ha (on ultrabasic rocks) and 1 ha (on the other substrates) for lower slope. Recruitment rates did not show a consistent pattern across geological substrates or topographies. Mortality rates were relatively high in almost all plots during the 1997–1999 period, including the El Niño drought, and in three plots on ultrabasic rocks during 2001–2005. Binomial logistic regression analyses showed that mortality during 1997–1999 increased with soil fertility (soluble phosphorus). Background mortality, excluding these periods, did not differ across geological substrates or topographies. The average growth rate during 1997–2011 was higher on more fertile soils and positively correlated with mortality during 1997–1999. We suggest that a high mortality rate during the drought period was related to high species diversity on more fertile soils, whereas a lower growth rate was related to stunted structures on poorer soils. [ABSTRACT FROM PUBLISHER]

Since 1991, researchers from approximately 45 nations have participated in eight International Conferences on Serpentine Ecology (ICSE). The Conferences are coordinated by the International Serpentine Ecology Society (ISES), a formal research society whose members study geological, pedological, biological and applied aspects of ultramafic (serpentine) ecosystems worldwide. These conferences have provided an international forum to discuss and synthesise multidisciplinary research, and have provided opportunities for scientists in distinct fields and from different regions of the world to conduct collaborative and interdisciplinary research. The 8th ICSE was hosted by Sabah Parks in Malaysia, on the island of Borneo, and attracted the largest delegation to date, 174 participants from 31 countries. This was the first time an ICSE was held in Asia, a region that hosts some of the world's most biodiverse ultramafic ecosystems. The presentations provided a cross-section of the current status of research in all aspects of ultramafic-biota relations. In this Special Issue of Australian Journal of Botany (Issues 1-2 combined and 3-4 combined), we have compiled a selection of papers from among the oral and poster presentations to provide insights into recent advances in geoecological and applied studies of ultramafic habitats worldwide. Here we provide a preview of select papers found in this Special Issue and summarise some of the contributions made during the 8th ICSE and describe some of the exciting challenges awaiting future research. The 8th ICSE was hosted by Sabah Parks in Malaysia attracted 174 participants from 31 countries and was the first held in Asia, the region that hosts some of the world's most biodiverse ultramafic ecosystems. Here we summarise some of the contributions made during the 8th ICSE and describe some of the exciting challenges awaiting future research. [ABSTRACT FROM AUTHOR]

Background: The picturesque limestone karsts across the Sino-Vietnamese border are renowned biodiversity hotspot, distinguished for extremely high endemism of calciphilous plants restricted to caves and cave-like microhabitats that have functioned as biological refugia on the otherwise harsh habitats. To understand evolutionary mechanisms underlying the splendid limestone flora, dated phylogeny is reconstructed for Asian Begonia, a species-rich genus on limestone substrates represented by no less than 60 species in southern China, using DNA sequences of nrITS and chloroplast rpL16 intron. The sampling includes 94 Begonia species encompassing most major Asian clades with a special emphasized on Chinese species. Results: Except for two tuberous deciduous species and a species with upright stems, a majority of Sino-Vietnamese limestone Begonia (SVLB), including sect. Coelocentrum (19 species sampled) and five species of sect. Diploclinium, Leprosae, and Petermannia, are rhizomatous and grouped in a strongly supported and yet internally poorly resolved clade (Clade SVLB), suggesting a single evolutionary origin of the adaptation to limestone substrates by rhizomatous species, subsequent species radiation, and a strong tendency to retain their ancestral niche. Divergence-time estimates indicate a late Miocene diversification of Clade SVLB, coinciding with the onset of the East Asian monsoon and the period of extensive karstification in the area. Conclusions: Based on our phylogenetic study, Begonia sect. Coelocentrum is recircumscribed and expanded to include other members of the Clade SVLB (sect. Diploclinium: B. cavaleriei, B. pulvinifera, and B. wangii; sect. Leprosae: B. cylindrica and B. leprosa; sect. Petermannia: B. sinofloribunda). Because species of Clade SVLB have strong niche conservatism to retain in their ancestral habitats in cave-like microhabitats and Begonia are generally poor dispersers prone to diversify allopatrically, we propose that extensive and continuous karstification of the Sino-Vietnamese limestone region facilitated by the onset of East Asian monsoon since the late Miocene has been the major driving force for species accumulation via geographic isolation in Clade SVLB. Morphologically species of Clade SVLB differ mainly in vegetative traits without apparent adaptive value, suggesting that limestone Begonia radiation is better characterized as non-adaptive, an underappreciated speciation mode crucial for rapid species accumulations in organisms of low vagility and strong niche conservatism. [ABSTRACT FROM AUTHOR]

Mountains of the tropical Pacific are influenced by synoptic-scale air subsidence, which causes a temperature inversion and a distinct dry meteorological condition above the inversion. The inversion appears at a lower altitude in the eastern Pacific where descending air of the Walker circulation prevails. On the other hand, if or how the alpine ecosystem of the tropical mountains of the western Pacific is influenced by dry synoptic-scale air subsidence is not well documented. We studied the vegetation and climate of the summit zone of Mount Kinabalu (4095 m) of Borneo. The leaf-size spectrum and physiognomy of forest community changed abruptly along the slope approximately at 3200 m from microphyll to leptophyll, suggesting that dry climatological conditions influence the vegetation above that altitude. Mean daily vapor pressure deficits (VPDs), estimated daily potential evapotranspiration (ET0), and the ratio of 30-day total ET0 to 30-day total rainfall increased drastically during El Niño and the magnitude of the increase was greater in the summit zone than in the montane zones. Increased VPDs during El Niño were linked with katabatic winds in the summit zone. We suggest that such irregular dry spells caused by synoptic-scale air subsidence in El Niño years can be a major factor for the formation of xeromorphic vegetation of the summit zone of Mount Kinabalu. [ABSTRACT FROM AUTHOR]

Biodiversity-rich tropical ultramafic areas are currently being impacted by land clearing and particularly by mine activities. The reclamation of ultramafic degraded areas requires a knowledge of pioneer plant species. The objective of this study is to highlight the functional traits of plants that colonize ultramafic areas after disturbance by fire or mining activities. This information will allow trait-assisted selection of candidate species for reclamation. Fifteen plots were established on ultramafic soils in Sabah (Borneo, Malaysia) disturbed by recurrent fires (FIRE plots) or by soil excavation and quarrying (MINE plots). In each plot, soil samples were collected and plant cover as well as species abundances were estimated. Fifteen functional traits related to revegetation, nutrient improvement, or Ni phytomining were measured in sampled plants. Vegetation of both FIRE and MINE plots was dominated by perennials with lateral spreading capacity (mainly by rhizomes). Plant communities displayed a conservative growth strategy, which is an adaptation to low nutrient availability on ultramafic soils. Plant height was higher in FIRE than in MINE plots, whereas the number of stems per plant was higher in MINE plots. Perennial plants with lateral spreading capacity and a conservative growth strategy would be the first choice for the reclamation of ultramafic degraded areas. Additional notes for increasing nutrient cycling, managing competition, and implementing of Ni-phytomining are also provided. [ABSTRACT FROM AUTHOR]

Since 1991, researchers from approximately 45 nations have participated in eight International Conferences on Serpentine Ecology (ICSE). The ICSE conferences are coordinated by the International Serpentine Ecology Society (ISES), a formal research society whose members study geological, pedological, biological and applied aspects of ultramafic ecosystems worldwide. These conferences have provided an international forum to discuss and synthesise multidisciplinary research, and have provided opportunities for scientists in distinct fields and from different regions of the world to conduct collaborative and interdisciplinary research. The 8th ICSE was hosted by Sabah Parks in Malaysia, on the island of Borneo, and attracted the largest delegation to date, 174 participants from 31 countries. This was the first time an ICSE was held in Asia, the region that hosts some of the world's most biodiverse ultramafic ecosystems. The presentations provided a cross-section of the current status of research in all aspects of serpentine-biota relations. In this Special Issue of Australian Journal of Botany, which encompasses two double issues (1-2 and 3-4), we have compiled a selection of papers from among the oral and poster presentations to provide insights into recent advances in geoecological and applied studies of serpentine habitats worldwide. The 8th ICSE was hosted by Sabah Parks in Malaysia attracted 174 participants from 31 countries and was the first held in Asia, the region that hosts some of the world's most biodiverse ultramafic ecosystems. [ABSTRACT FROM AUTHOR]