Rain Forest

14,000,000 Leading Edge Experts on the ideXlab platform

Scan Science and Technology

Contact Leading Edge Experts & Companies

Scan Science and Technology

Contact Leading Edge Experts & Companies

The Experts below are selected from a list of 52146 Experts worldwide ranked by ideXlab platform

David M. J. S. Bowman - One of the best experts on this subject based on the ideXlab platform.

  • Phosphorus limits Eucalyptus grandis seedling growth in an unburnt Rain Forest soil.
    Frontiers in Plant Science, 2014
    Co-Authors: David Y. P. Tng, Gregory J. Jordan, David P. Janos, Ellen Weber, David M. J. S. Bowman
    Abstract:

    Although Rain Forest is characterized as pyrophobic, pyrophilic giant eucalypts grow as Rain Forest emergents in both temperate and tropical Australia. In temperate Australia, such eucalypts depend on extensive, infrequent fires to produce conditions suitable for seedling growth. Little is known, however, about constRaints on seedlings of tropical giant eucalypts. We tested whether seedlings of Eucalyptus grandis experience edaphic constRaints similar to their temperate counterparts. We hypothesized that phosphorous addition would alleviate edaphic constRaints. We grew seedlings in a factorial experiment combining fumigation (to simulate nutrient release and soil pasteurization by fire), soil type (E. grandis Forest versus Rain Forest soil) and phosphorus addition as factors. We found that phosphorus was the principal factor limiting E. grandis seedling survival and growth in Rain Forest soil, and that fumigation enhanced survival of seedlings in both E. grandis Forest and Rain Forest soil. We conclude that similar to edaphic constRaints on temperate giant eucalypts, mineral nutrient and biotic attributes of a tropical Rain Forest soil may hamper E. grandis seedling establishment. In Rain Forest soil, E. grandis seedlings benefited from conditions akin to a fire-generated ashbed (i.e., an “ashbed effect”).

  • Giant eucalypts – globally unique fire‐adapted RainForest trees?
    New Phytologist, 2012
    Co-Authors: David Y. P. Tng, Grant J. Williamson, Gregory J. Jordan, David M. J. S. Bowman
    Abstract:

    Contents   Summary 1001 I. Introduction 1001 II. Giant eucalypts in a global context 1002 III. Giant eucalypts – taxonomy and distribution 1004 IV. Growth of giant eucalypts 1006 V. Fire and regeneration of giant eucalypts 1008 VI. Are giant eucalypts different from other Rain-Forest trees? 1009 VII. Conclusions 1010   Acknowledgements 1011   References 1011 Summary Tree species exceeding 70 m in height are rare globally. Giant gymnosperms are concentrated near the Pacific coast of the USA, while the tallest angiosperms are eucalypts (Eucalyptus spp.) in southern and eastern Australia. Giant eucalypts co-occur with Rain-Forest trees in eastern Australia, creating unique vegetation communities comprising fire-dependent trees above fire-intolerant Rain-Forest. However, giant eucalypts can also tower over shrubby understoreys (e.g. in Western Australia). The local abundance of giant eucalypts is controlled by interactions between fire activity and landscape setting. Giant eucalypts have features that increase flammability (e.g. oil-rich foliage and open crowns) relative to other Rain-Forest trees but it is debatable if these features are adaptations. Probable drivers of eucalypt gigantism are intense intra-specific competition following severe fires, and inter-specific competition among adult trees. However, we suggest that this was made possible by a general capacity of eucalypts for ‘hyper-emergence’. We argue that, because giant eucalypts occur in Rain-Forest climates and share traits with Rain-Forest pioneers, they should be regarded as long-lived Rain-Forest pioneers, albeit with a particular dependence on fire for regeneration. These unique ecosystems are of high conservation value, following substantial clearing and logging over 150 yr.

  • firescape ecology how topography determines the contrasting distribution of fire and Rain Forest in the south west of the tasmanian wilderness world heritage area
    Journal of Biogeography, 2011
    Co-Authors: Samuel W Wood, Brett P Murphy, David M. J. S. Bowman
    Abstract:

    Aim  To test the hypothesis that ‘islands’ of fire-sensitive Rain Forest are restricted to topographic fire refugia and investigate the role of topography–fire interactions in fire-mediated alternative stable state models. Location  A vegetation mosaic of moorland, sclerophyll scrub, wet sclerophyll eucalypt Forest and Rain Forest in the rugged, fire-prone landscapes of south-west Tasmania, Australia. Methods  We used geospatial statistics to: (1) identify the topographic determinants of Rain Forest distribution on nutrient-poor substrates, and (2) identify the vegetation and topographic variables that are important in controlling the spatial pattern of a series of very large fires (> 40,000 ha) that were mapped using Landsat Thematic Mapper (TM) satellite imagery. Results  Rain Forest was more likely to be found in valleys and on steep south-facing slopes. Fires typically burned within highly flammable treeless moorland and stopped on boundaries with less flammable surrounding vegetation types such as wet sclerophyll Forest and Rain Forest. Controlling for the effect of vegetation, fires were most likely to burn on flats, ridges and steep north-facing slopes and least likely to burn in valleys and on steep south-facing slopes. These results suggest an antagonism between fire and Rain Forest, in which Rain Forest preferentially occupies parts of the landscape where fire is least likely to burn. Main conclusions  The distribution of Rain Forest on nutrient-poor substrates was clearly related to parts of the landscape that are protected from fire (i.e. topographic fire refugia). The relative flammability of vegetation types at the landscape scale offers support to the proposed hierarchy of fire frequencies (moorland > scrub > wet sclerophyll > Rain Forest) that underpins the ecological models proposed for the region. The interaction between fire occurrence and a range of topographic variables suggests that topography plays an important role in mediating the fire–vegetation feedbacks thought to maintain vegetation mosaics in south-west Tasmania. We suggest that these fire–topography interactions should be included in models of fire-mediated alternative stable vegetation states in other fire-prone landscapes.

  • drivers of Rain Forest boundary dynamics in kakadu national park northern australia a field assessment
    Journal of Tropical Ecology, 2007
    Co-Authors: Daniel S Banfai, David M. J. S. Bowman
    Abstract:

    Understanding the causes of savanna–Forest dynamics is vital as small but widespread changes in the extent of tropical Forests can have major impacts on global climate, biodiversity and human well-being. Comparison of aerial photographs for 50 Rain-Forest patches in Kakadu National Park had previously revealed a landscape-wide monotonic expansion of Rain-Forest boundaries between 1964 and 2004. Here floristic, structural, environmental and disturbance attributes of the changes were investigated by sampling 588 plots across 30 Rain-Forest patches. Areas that had changed from savanna to Rain Forest were associated with a significantly higher abundance of Rain-Forest trees and less grasses, relative to stable savanna areas. Ordination analyses showed that overall floristic composition was not significantly different between newly established Rain Forest and longer established Rain Forest. Generalized linearmodels also indicated that contemporary levels of disturbance (fire and feral animal impact) and environmental variables (slope and soil texture) were poor predictors of historical vegetation change. We concluded that (1) the Rain-Forest boundaries are highly dynamic at the decadal scale; (2) Rain-Forest expansion is consistent with having been driven by global environmental change phenomena such as increases in Rainfall and atmospheric CO2; and (3) expansion will continue if current climatic trends and management conditions persist.

Hua Zhu - One of the best experts on this subject based on the ideXlab platform.

  • Species composition and biogeography of tropical montane Rain Forest in southern Yunnan of China
    The Gardens' Bulletin Singapore, 2006
    Co-Authors: Hua Zhu, H. Wang
    Abstract:

    The species composition, physiognomy and biogeography of tropical montane Rain Forest in southern Yunnan, SW China, have been studied based on data from 10 sampling plots and a complete floristic inventory. Two separate communities are recognized: a Mastixia euonymoides-Phoebe megacalyx Forest and a Parakmeria yunnanensis-Gymnanthes remota Forest based mainly on species composition and Forest structures. The tropical montane Rain Forest is characterized by evergreen meso-phanerophytes and micro-phanerophytes with simple, leathery and entire mesophyllous leaves, more or less frequent woody lianas and epiphytes, abundant herbaceous phanerophytes. However, it has few buttresses or cauliflory in physiognomy. The montane Rain Forest has similar species diversity to the lowland seasonal Rain Forest in the region. This indicates that species richness is not necessarily reduced with increasing altitude. We suggest this Rain Forest is a type of lower montane Rain Forest based mainly on its physiognomy, structure and floristics, but one that occurs at a higher altitude than those in equatorial SE Asia. The montane Rain Forest is dominated, in terms of species richness, by Lauraceae, Euphorbiaceae, Fagaccae, Theaceae, Rubiaceae and Papilionaceae, but by Lauraceae, Magnoliaceae, Euphorbiaceae, Fagaceae, Mastixiaceae and Nyssaceae in terms of phytosociological importance. In floristic composition, a total of 623 native species in 327 genera and 115 families of seed plants were recorded from the montane Rain Forest, of which recognizably 'tropical' elements contributed about 78.9% at the generic level and more than 80% at the specific level. Plants of tropical Asian distribution contribute 63.7% of the total sum of species. We conclude that the montane Rain Forest has strong tropical Asian affinities floristically even though it occurs at the northern margin of mainland SE Asia and at a higher altitude.

  • A tropical seasonal Rain Forest at its altitudinal and latitudinal limits in southern Yunnan, SW China
    The Gardens' Bulletin Singapore, 2004
    Co-Authors: Hua Zhu
    Abstract:

    The tropical seasonal Rain Forest (semi-evergreen Rain Forest) in Caiyanghe Nature Reserve, Simao, Yunnan, China, is at the northern and altitudinal limits of tropical Rain Forest in Asia. It shares the main physiognomic characteristics of tropical Rain Forest. Compared with lowland Rain Forests in China and equatorial regions in Asia, it has lower species diversity with more micro- and nano-phanerophytes and herbaceous phanerophytes in the life form spectra, more microphyllous plants and more plants with non-entire leaves. In floristic composition, it is dominated by tropical Asian elements and characterized by the Indo-Malayan tropical flora. It is suggested that the occurrence of tropical Rain Forest in southern Yunnan is more influenced by topography and local habitats than the regional climate.

  • Ecological and biogeographical studies on the tropical Rain Forest of south Yunnan, SW China with a special reference to its relation with Rain Forests of tropical Asia
    Journal of Biogeography, 1997
    Co-Authors: Hua Zhu
    Abstract:

    Ecological and biogeographic analyses of the tropical Rain Forest in south Yunnan were made using data from seventeen sample plots and floristic inventories of about 1000 species of seed plants. The Rain Forest is shown to be a type of true tropical Rain Forest because it has almost the same profile, physiognomic characteristics, species richness per unit area, numbers of individuals in each tree species and diameter classes of trees as classic lowland tropical Rain Forests. As the area is at the northern margin of monsoonal tropics, the Rain Forest differs from equatorial lowland Rain Forests in having some deciduous trees in the canopy layer, fewer megaphanaerophytes and epiphytes but more species of lianas as well as more species of microphylls. In its floristic composition, about 80% of total families, 94% of total genera and more than 90% of total species are tropical, of which about 38% of genera and 74% of species are tropical Asian. Furthermore, the Rain Forest has not only almost the same families and genera, but also the same families rank in the top ten both in species richness and in dominance of stems, as lowland Forests in southeast Asia. It is indisputable that the flora of the Rain Forest is part of the tropical Asian flora. However, most of the tropical families and genera have their northern limits in south Yunnan and most have their centre of species diversity in Malesia. More strictly tropical families and genera have relatively lower species richness and importance compared with lowland Rain Forests in tropical southeast Asia. Thus, the flora also shows characteristics of being at the margin of the tropics. Based mainly on physiognomy and floristic composition the tropical Rain Forest of Yunnan is classified into two types, i.e. seasonal Rain Forest and wet seasonal Rain Forest, the latter is further divided into two subtypes, i.e. mixed Rain Forest and dipterocarp Rain Forest. From analysis of geographic elements it is also shown that the tropical Rain Forest of Yunnan occurs at a geographical nexus with its flora coming mainly from four sources, i.e. Malesia, south Himalayas, Indochina and China.

Mikko Siitonen - One of the best experts on this subject based on the ideXlab platform.

  • the fragmented atlantic Rain Forest of brazil size shape and distribution of Forest fragments
    Biodiversity and Conservation, 1998
    Co-Authors: Pertti Ranta, Tom Blom, Jari Niemela, Elina Joensuu, Mikko Siitonen
    Abstract:

    The geographical characteristics of a total of 1839 Forest fragments surrounded by sugar cane fields were studied in the Brazilian Atlantic Rain Forest region of the northeastern state of Pernambuco. The size and shape of the fragments as well as inter-fragment distances and the effects of varying edge width were examined using a geographical information system. The analyses show that the fragments are relatively small and close to each other. Approximately 48% of the Rain Forest fragments are 100 hectares. Forest fragments are close to each other, as fragments located 50m or less apart formed groups that included ca. 50% of the total Forest area. At 350m inter-fragment distance, 98% of the Rain Forest area was included in groups of fragments. Due to the small size and irregular shape of the fragments, the total area of edge zone exceeds that of the interior habitat when the edge width is ca. 60m. At an edge width of 300m ca. 94% of the total fragment area is edge zone. For conservation purposes, ways of establishing networks of Forest fragments connected by corridors and stepping stone fragments are demonstrated using GIS. Simulations using these techniques show that reForestation of sugar cane fields between the Forest fragments would considerably increase the area of interior Forest habitat and connectivity between fragments.

Frank J Sterck - One of the best experts on this subject based on the ideXlab platform.

  • wood mechanics allometry and life history variation in a tropical Rain Forest tree community
    New Phytologist, 2006
    Co-Authors: H Van Gelder, Lourens Poorter, Frank J Sterck
    Abstract:

    Summary • Wood density plays a central role in the life-history variation of trees, and has important consequences for mechanical properties of wood, stem and branches, and tree architecture. • Wood density, modulus of rupture, modulus of elasticity, and safety factors for buckling and bending were determined for saplings of 30 Bolivian Rain Forest tree species, and related to two important life-history axes: juvenile light demand and maximum adult stature. • Wood density was strongly positively related to wood strength and stiffness. Species safety factor for buckling was positively related to wood density and stiffness, but tree architecture (height : diameter ratio) was the strongest determinant of mechanical safety. Shade-tolerant species had dense and tough wood to enhance survival in the understorey, whereas pioneer species had low-density wood and low safety margins to enhance growth in gaps. Pioneer and shade-tolerant species showed opposite relationships between species traits and adult stature. • Light demand and adult stature affect wood properties, tree architecture and plant performance in different ways, contributing to the coexistence of Rain Forest species.

Samuel W Wood - One of the best experts on this subject based on the ideXlab platform.

  • firescape ecology how topography determines the contrasting distribution of fire and Rain Forest in the south west of the tasmanian wilderness world heritage area
    Journal of Biogeography, 2011
    Co-Authors: Samuel W Wood, Brett P Murphy, David M. J. S. Bowman
    Abstract:

    Aim  To test the hypothesis that ‘islands’ of fire-sensitive Rain Forest are restricted to topographic fire refugia and investigate the role of topography–fire interactions in fire-mediated alternative stable state models. Location  A vegetation mosaic of moorland, sclerophyll scrub, wet sclerophyll eucalypt Forest and Rain Forest in the rugged, fire-prone landscapes of south-west Tasmania, Australia. Methods  We used geospatial statistics to: (1) identify the topographic determinants of Rain Forest distribution on nutrient-poor substrates, and (2) identify the vegetation and topographic variables that are important in controlling the spatial pattern of a series of very large fires (> 40,000 ha) that were mapped using Landsat Thematic Mapper (TM) satellite imagery. Results  Rain Forest was more likely to be found in valleys and on steep south-facing slopes. Fires typically burned within highly flammable treeless moorland and stopped on boundaries with less flammable surrounding vegetation types such as wet sclerophyll Forest and Rain Forest. Controlling for the effect of vegetation, fires were most likely to burn on flats, ridges and steep north-facing slopes and least likely to burn in valleys and on steep south-facing slopes. These results suggest an antagonism between fire and Rain Forest, in which Rain Forest preferentially occupies parts of the landscape where fire is least likely to burn. Main conclusions  The distribution of Rain Forest on nutrient-poor substrates was clearly related to parts of the landscape that are protected from fire (i.e. topographic fire refugia). The relative flammability of vegetation types at the landscape scale offers support to the proposed hierarchy of fire frequencies (moorland > scrub > wet sclerophyll > Rain Forest) that underpins the ecological models proposed for the region. The interaction between fire occurrence and a range of topographic variables suggests that topography plays an important role in mediating the fire–vegetation feedbacks thought to maintain vegetation mosaics in south-west Tasmania. We suggest that these fire–topography interactions should be included in models of fire-mediated alternative stable vegetation states in other fire-prone landscapes.