Ecological processes maintaining differential tree species distributions in an Australian subtropical rain forest: implications for models of species coexistence

All stems ≥ 1 cm dbh were measured, tagged, mapped and identified on a 1-ha plot of rain forest at Gambubal State Forest, south-east Queensland, Australia. The spatial patterns and size class distributions of 11 common tree species on the plot were assessed to search for mechanisms determining their distribution and abundance. The forest was species-poor in comparison to many lowland tropical forests and the common species are therefore present at relatively high densities. Despite this, only limited evidence was found for the operation of density-dependent processes at Gambubal. Daphnandra micrantha saplings were clumped towards randomly spaced adults, indicating a shift of distribution over time caused by differential mortality of saplings in these adult associated clumps. Ordination of the species composition in 25-m × 25-m subplots revealed vegetation gradients at that scale, which corresponded to slope across the plot. Adult basal area was dominated by a few large individuals of Sloanea woollsii but the comparative size class distributions and replacement probabilities of the 11 common species suggest that the forest will undergo a transition to a more mixed composition if current conditions persist. The current cohort of large S. woollsii individuals probably established after a large-scale disturbance event and the forest has not attained an equilibrium species composition.

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Development of forest soils in the Krkonoše Mts. in the period 1980–2009

Journal of Forest Science ◽

10.17221/79/2010-jfs ◽

2010 ◽

Vol 56 (No. 11) ◽

pp. 485-504 ◽

Cited By ~ 5

Author(s):

K. Matějka ◽

S. Vacek ◽

V. Podrázský

Keyword(s):

Species Composition ◽

Tree Species ◽

Large Scale ◽

Vegetation Change ◽

Soil Conditions ◽

Available Phosphorus ◽

Mountain Range ◽

Site Conditions ◽

Tree Species Composition ◽

Spruce Stands

This paper documents the development of soil conditions in the set of 32 permanent research plots in the Krkono&scaron;e (Giant) Mts. These plots represent an altitudinal gradient covering the ecosystems of beech, mixed beech-spruce and spruce stands. In all plots, representing the site conditions of the highest areas of the mountain range, standard soil pits were prepared and the soil sampling was performed in autumn of years 1980, 1993, 1998, 2003 and 2009. The results reflect extreme site conditions, soil acidification, large scale surface liming and in minor extent also different tree species composition of the stands. The general type of the soil-genesis is represented by the podzolisation, overlapping the other soil-genetic factors, including the tree species composition. Nevertheless, this development is mostly expressed in the spruce stands. The beech dominance and/or co-dominance are reflected especially by more efficient N-cycling, higher pH, S and V values and fluctuation and lower extractable Al3+ content. More efficient cycling in beech ecosystems is insignificantly documented for plant available phosphorus, calcium and magnesium contents; on the contrary higher dynamics for iron ions was registered in the spruce stands. The long-term soil dynamics with a hysteresis (evident on the base of ordination analysis) can be divided into some periods – processes of acidification (typical in the 1980's samples), liming (main effect in 1993 and 1998) and regeneration (2003, 2009). Other features, important for the soil development, are probably related to the vegetation change, but this relation is not statistically significant.

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Habitat selection determines abundance, richness and species composition of beetles in aquatic communities

Biology Letters ◽

10.1098/rsbl.2005.0310 ◽

2005 ◽

Vol 1 (3) ◽

pp. 370-374 ◽

Cited By ~ 86

Author(s):

Christopher A Binckley ◽

William J Resetarits

Keyword(s):

Species Richness ◽

Habitat Selection ◽

Species Composition ◽

Large Scale ◽

Habitat Preferences ◽

Differential Mortality ◽

Aquatic Communities ◽

Species Sorting ◽

Random Dispersal ◽

Random Site

Distribution and abundance patterns at the community and metacommunity scale can result from two distinct mechanisms. Random dispersal followed by non-random, site-specific mortality (species sorting) is the dominant paradigm in community ecology, while habitat selection provides an alternative, largely unexplored, mechanism with different demographic consequences. Rather than differential mortality, habitat selection involves redistribution of individuals among habitat patches based on perceived rather than realized fitness, with perceptions driven by past selection. In particular, habitat preferences based on species composition can create distinct patterns of positive and negative covariance among species, generating more complex linkages among communities than with random dispersal models. In our experiments, the mere presence of predatory fishes, in the absence of any mortality, reduced abundance and species richness of aquatic beetles by up to 80% in comparison with the results from fishless controls. Beetle species' shared habitat preferences generated distinct patterns of species richness, species composition and total abundance, matching large-scale field patterns previously ascribed to random dispersal and differential mortality. Our results indicate that landscape-level patterns of distribution and species diversity can be driven to a large extent by habitat selection behaviour, a critical, but largely overlooked, mechanism of community and metacommunity assembly.

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Change in leaf structure in relation to crown position and size class for tree species within a Sri Lankan tropical rain forest

Botany ◽

10.1139/b08-039 ◽

2008 ◽

Vol 86 (6) ◽

pp. 633-640 ◽

Cited By ~ 15

Author(s):

P. A.K.A.K. Panditharathna ◽

B. M.P. Singhakumara ◽

H. P. Griscom ◽

M. S. Ashton

Keyword(s):

Tree Species ◽

Rain Forest ◽

Tropical Rain Forest ◽

Size Class ◽

Leaf Structure ◽

Sri Lankan ◽

Size Classes ◽

Canopy Trees ◽

Crown Position ◽

Closed Canopy

The purpose of our study was to examine change in leaf structure (anatomy and morphology) through different phases of tree size and crown position within a Sri Lankan rain forest. We selected four late-successional canopy species that represented dominant genera ( Shorea , Mesua ) within an Asian tropical rain forest. All are considered shade-tolerant and capable of growing to maturity beneath closed-canopy late-successional forests. Species within each genus were either restricted to seepages and bottom slopes (valley species) or to upper slopes and ridges (ridge species). The size classes represented (i) seedlings, (ii) saplings, (iii) poles growing beneath closed-canopy conditions, and (iv) trees of the rain forest canopy. Between size classes, leaves were thicker and with higher stomatal densities for canopy trees than for seedling, sapling, and pole size classes. Plasticities for measures of leaf structure were greater for ridge species than valley species; except for cuticle thickness, which showed the opposite trend (valley > ridge). Area, length, and width of leaves attained maxima for the sapling size class for all species. Drip-tip lengths were greatest for seedlings of all species, and least for canopy trees. Trends in leaf structure and morphology dimensions across size classes for late-successional canopy tree species are the same as those trends reported between rain forest species of different habitat strata (e.g., understory shrubs versus upper canopy trees). Our results suggest leaf dimensions could provide robust measures of environment, irrespective of species, or size class of tree.

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Tree species identification on large-scale aerial photographs in a tropical rain forest, French Guiana—application for management and conservation

Forest Ecology and Management ◽

10.1016/j.foreco.2005.12.046 ◽

2006 ◽

Vol 225 (1-3) ◽

pp. 51-61 ◽

Cited By ~ 10

Author(s):

Trichon Valérie ◽

Julien Marie-Pierre

Keyword(s):

Species Identification ◽

Tree Species ◽

Rain Forest ◽

Tropical Rain Forest ◽

Large Scale ◽

French Guiana ◽

Aerial Photographs ◽

Management And Conservation

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Shade-tolerance of seedlings of rain-forest trees: monodominants vs. subordinates and episodic vs. continuous regenerators

Journal of Tropical Ecology ◽

10.1017/s0266467415000486 ◽

2015 ◽

Vol 31 (6) ◽

pp. 541-552 ◽

Cited By ~ 4

Author(s):

Jennifer Read ◽

Stéphane McCoy ◽

Tanguy Jaffré

Keyword(s):

Rain Forest ◽

Shade Tolerance ◽

Large Scale ◽

New Caledonia ◽

Dark Respiration ◽

High Plasticity ◽

Forest Trees ◽

Large Scale Disturbance ◽

Leaf Level ◽

Net Assimilation

Abstract:Several monodominant rain-forest trees in New Caledonia have population size structures suggesting establishment following large-scale disturbance, with eventual replacement by shade-tolerant species predicted in the absence of future disturbance. Links of dominance and population dynamics to leaf-level photosynthesis were investigated in seedlings of 20 tree species from these forests, grown in experimental sun and shade conditions. In particular, we tested whether episodically regenerating (ER) species, including monodominants, have higher assimilation rates at high irradiances and lower tolerance of shade than continuously regenerating species (CR). ER species had higher maximum net assimilation rates (Amax-area) in sun plants (9.6 ± 0.4 μmol m−2 s−1) than CR species (6.2 ± 0.3 μmol m−2 s−1) and high plasticity, typical of shade-intolerant species, but monodominant species did not differ from other ER species. CR species had leaf-level traits consistent with shade tolerance, including lower dark respiration rates (Rd-area = 0.47 ± 0.03μmol m−2 s−1; Rd-mass = 7 ± 1 nmol g−1 s−1) than ER species (Rd-area = 0.63 ± 0.06 μmol m−2 s−1; Rd-mass = 11 ± 2 nmol g−1 s−1) in shade plants. Hence leaf-level assimilation traits were largely consistent with regeneration patterns, but do not explain why some shade-intolerant species can achieve monodominance.

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A test of the hypothesis of ecological equivalence in an Australian subtropical rain forest

Journal of Tropical Ecology ◽

10.1017/s0266467402002249 ◽

2002 ◽

Vol 18 (3) ◽

pp. 327-352 ◽

Cited By ~ 1

Author(s):

Guy C. Penfold ◽

David Lamb

Keyword(s):

Soil Ph ◽

Tree Species ◽

Rain Forest ◽

Light Availability ◽

Positive Association ◽

Common Species ◽

Species Differentiation ◽

N Availability ◽

P Availability ◽

Ecological Differentiation

We tested the hypothesis that tree species in a subtropical rain forest in south-east Queensland are ecologically equivalent and therefore have identical environmental requirements for their regeneration. We assessed the evidence that juveniles of species differed in their distributions in treefall gap microsites and along gradients of light availability, soil pH, soil PO4-P availability and soil NO3-N availability. Pairwise comparisons were made on a subset of the common species selected on the basis that they showed a relatively high level of positive association, and would therefore, a priori, be expected to have similar regeneration requirements. Detailed comparisons between the species failed to demonstrate evidence for species differentiation with respect to their tolerance of the disturbance associated with gap microsites or to the gradient of NO3-N availability. However, species differed markedly in their distributions along the soil pH gradient and along the gradients of light availability and soil PO4-P availability. The overall level of ecological differentiation between the species is high: seven out of the 10 possible species pairings showed evidence for ecological differentiation. Such niche differentiation amongst the juveniles of tree species may play an important role in maintaining the species richness of rain-forest communities.

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Tree communities of white-sand and terra-firme forests of the upper Rio Negro

Acta Amazonica ◽

10.1590/s0044-59672011000400010 ◽

2011 ◽

Vol 41 (4) ◽

pp. 521-544 ◽

Cited By ~ 31

Author(s):

Juliana Stropp ◽

Peter Van der Sleen ◽

Paulo Apóstolo Assunção ◽

Adeilson Lopes da Silva ◽

Hans Ter Steege

Keyword(s):

Species Composition ◽

Tree Species ◽

Large Scale ◽

Species Abundance ◽

Tree Diversity ◽

Terra Firme ◽

Floristic Similarity ◽

White Sand ◽

Rio Negro ◽

Tree Communities

The high tree diversity and vast extent of Amazonian forests challenge our understanding of how tree species abundance and composition varies across this region. Information about these parameters, usually obtained from tree inventories plots, is essential for revealing patterns of tree diversity. Numerous tree inventories plots have been established in Amazonia, yet, tree species composition and diversity of white-sand and terra-firme forests of the upper Rio Negro still remain poorly understood. Here, we present data from eight new one-hectare tree inventories plots established in the upper Rio Negro; four of which were located in white-sand forests and four in terra-firme forests. Overall, we registered 4703 trees > 10 cm of diameter at breast height. These trees belong to 49 families, 215 genera, and 603 species. We found that tree communities of terra-firme and white-sand forests in the upper Rio Negro significantly differ from each other in their species composition. Tree communities of white-sand forests show a higher floristic similarity and lower diversity than those of terra-firme forests. We argue that mechanisms driving differences between tree communities of white-sand and terra-firme forests are related to habitat size, which ultimately influences large-scale and long-term evolutionary processes.

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Region effects influence local tree species diversity

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1523683113 ◽

2016 ◽

Vol 113 (3) ◽

pp. 674-679 ◽

Cited By ~ 54

Author(s):

Robert E. Ricklefs ◽

Fangliang He

Keyword(s):

Tree Species ◽

Physical Environment ◽

Large Scale ◽

Environmental Heterogeneity ◽

Species Coexistence ◽

Forest Tree ◽

Local Climate ◽

Coexisting Species ◽

Species Production ◽

Significant Region

Global patterns of biodiversity reflect both regional and local processes, but the relative importance of local ecological limits to species coexistence, as influenced by the physical environment, in contrast to regional processes including species production, dispersal, and extinction, is poorly understood. Failure to distinguish regional influences from local effects has been due, in part, to sampling limitations at small scales, environmental heterogeneity within local or regional samples, and incomplete geographic sampling of species. Here, we use a global dataset comprising 47 forest plots to demonstrate significant region effects on diversity, beyond the influence of local climate, which together explain more than 92% of the global variation in local forest tree species richness. Significant region effects imply that large-scale processes shaping the regional diversity of forest trees exert influence down to the local scale, where they interact with local processes to determine the number of coexisting species.

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Microhabitat specialization of tropical rain-forest canopy trees in the Sovi Basin, Viti Levu, Fiji Islands

Journal of Tropical Ecology ◽

10.1017/s0266467411000241 ◽

2011 ◽

Vol 27 (5) ◽

pp. 491-501 ◽

Cited By ~ 14

Author(s):

Gunnar Keppel ◽

Marika V. Tuiwawa ◽

Alifereti Naikatini ◽

Isaac A. Rounds

Keyword(s):

Species Diversity ◽

Tree Species ◽

Rain Forest ◽

Forest Canopy ◽

Niche Differentiation ◽

Forest Tree ◽

Common Species ◽

Habitat Specificity ◽

Canopy Trees ◽

Fiji Islands

Abstract:Island biotas often have lower species diversity and less intense competition has been hypothesized as a result. This should result in lower habitat specificity compared with mainland habitats due to larger realized niches. We investigate microhabitat associations of canopy trees with regard to differences in topography on an oceanic island (Viti Levu, Fiji) using twenty 10 × 60-m plots. We find high tree-species diversity (112 species with dbh ≥ 10 cm in a total of 1.08 ha) and high endemism (c. 60%), compared with other islands in Western Polynesia. Our sample plots aggregate into three distinct groups that are mostly defined by micro-topography: (1) ridges and steep slopes (well-drained sites), (2) moderate slopes and ridge flats (moderate drainage), and (3) flats (poor drainage). Associations with microhabitat are found for more than 50% of the 41 most common species but only one species is apparently restricted to a single habitat. These findings are similar to other rain forests and demonstrate considerable niche differentiation among island rain-forest tree species.

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