Effects of topography, soil type and forest age on the frequency and size distribution of canopy gap disturbances in a tropical forest

Lobo, Elena; Dalling, James W.

doi:10.5194/bg-10-6769-2013

Cited by 32 publications

(37 citation statements)

References 42 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Similar patterns are observed in flooded vs. terra firma neotropical forest types Boyd et al, 2013;Coomes and Grubb, 1996). Recent applications of airborne laser scanning (ALS) have identified power-law GSFDs in the neotropics (Asner et al, , 2014Boyd et al, 2013;Espírito-Santo et al, 2014;Kellner and Asner, 2009;Lobo and Dalling, 2013) and Hawaii (Kellner and Asner, 2009;Kellner et al, 2011). Our analysis of an Indomalayan tropical PSF landscape finds a very wide range of scaling exponents α ranging from 1.66 to 3.76 across all old-growth sites and canopy cross-sections (Fig.…”

Section: Forest Height and Canopy Structure Along The Peat Domementioning

confidence: 65%

“…Scaling exponent α of the GSFD Scaling parameter determining the decrease in frequency of gaps as gap size increases. It also relates to the ratio of large to small gaps (Lobo and Dalling 2013).…”

Section: Metric Descriptionmentioning

confidence: 99%

“…2ce). Recent studies using ALS to detect canopy gaps have fitted a power law to describe the GSFD Boyd et al, 2013;Espírito-Santo et al, 2014;Kellner and Asner, 2009;Kellner et al, 2011;Lobo and Dalling, 2013).…”

Section: Gap Size Frequency Distributionmentioning

confidence: 99%

See 2 more Smart Citations

Landscape-scale changes in forest canopy structure across a partially logged tropical peat swamp

Wedeux

Coomes

2015

Biogeosciences

View full text Add to dashboard Cite

Forest canopy structure is strongly influenced by environmental factors and disturbance, and in turn influences key ecosystem processes including productivity, evapotranspiration and habitat availability. In tropical forests increasingly modified by human activities, the interplay between environmental factors and disturbance legacies on forest canopy structure across landscapes is practically unexplored. We used airborne laser scanning (ALS) data to measure the canopy of old-growth and selectively logged peat swamp forest across a peat dome in Central Kalimantan, Indonesia, and quantified how canopy structure metrics varied with peat depth and under logging. Several million canopy gaps in different height cross-sections of the canopy were measured in 100 plots of 1 km 2 spanning the peat dome, allowing us to describe canopy structure with seven metrics. Old-growth forest became shorter and had simpler vertical canopy profiles on deeper peat, consistent with previous work linking deep peat to stunted tree growth. Gap size frequency distributions (GSFDs) indicated fewer and smaller canopy gaps on the deeper peat (i.e. the scaling exponent of Pareto functions increased from 1.76 to 3.76 with peat depth). Areas subjected to concessionary logging until 2000, and illegal logging since then, had the same canopy top height as old-growth forest, indicating the persistence of some large trees, but mean canopy height was significantly reduced. With logging, the total area of canopy gaps increased and the GSFD scaling exponent was reduced. Logging effects were most evident on the deepest peat, where nutrient depletion and waterlogged conditions restrain tree growth and recovery. A tight relationship exists between canopy structure and peat depth gradient within the old-growth tropical peat swamp forest. This relationship breaks down after selective logging, with canopy structural recovery, as observed by ALS, modulated by environmen-tal conditions. These findings improve our understanding of tropical peat swamp ecology and provide important insights for managers aiming to restore degraded forests.Published by Copernicus Publications on behalf of the European Geosciences Union.

show abstract

Section: Forest Height and Canopy Structure Along The Peat Domementioning

confidence: 65%

Section: Metric Descriptionmentioning

confidence: 99%

See 1 more Smart Citation

Landscape-scale changes in forest canopy structure across a partially logged tropical peat swamp

Wedeux

Coomes

2015

Biogeosciences

View full text Add to dashboard Cite

show abstract

“…The co-formation of soil units by spatially non-random disturbances could lead to an increase of taxonomic pedodiversity and self-organization over time, which was empirically demonstrated by Phillips (2001) and Saldaña and Ibañez (2004) in chronosequences of fluvial terraces. In a rain forest, Lobo and Dalling (2013) revealed a significant relation between soil type and canopy disturbance regime. The importance of past disturbances in pedodiversity can be quantified by a calculation of soil complexity (Phillips, 2013a).…”

Section: Discussionmentioning

confidence: 99%

Disturbances can control fine-scale pedodiversity in old-growth forests: is the soil evolution theory disturbed as well?

et al. 2014

View full text Add to dashboard Cite

Abstract. Biota–soil interactions in natural ecosystems are the subject of considerable research. Our hypothesis is that individual trees play a significant role through biomechanical and biochemical disturbances affecting soil formation in temperate forests, resulting in a complex spatial pattern of disturbance regimes and a close relationship between disturbance histories and soil units. In Žofínský Prales (Czech Republic) – the fourth oldest, continuously protected reserve in Europe and the first site of global research network SIGEO (Smithsonian Institution Global Earth Observatories) in continental Europe – we compared extensive dendrochronological, soil and pit–mound microtopography data both temporally and spatially from an area of anthropogenically unaffected 42 ha collected from 2008–2012. These data sets differ in terms of information complexity and length of memory: tree cores contain complex information about the disturbance history of the past 350 years, footprints of disturbances from the uprooting of a specific tree can persist 1700 years, and soils represent an extensive composite phenotype that has been developing for at least the entire postglacial period (10 500 years). On average, 6.18–13.41% of the canopy on individual soil units was disturbed per decade. Even though the "backbone" of key events in the development of the forest ecosystem remained the same (e.g. the 1870s, 1880s and 1980s), the internal structure of disturbance history often differed among soil units; the most exceptional were Gleysols and Histosols, where important feedback from soil to trees was expected. However, the characteristics of treethrow dynamics as well as the frequencies of stronger releases in core series also significantly differed along a gradient of terrestrial soil weathering and leaching (Haplic Cambisols – Dystric Cambisols – Entic Podzols – Albic Podzols). These results suggest the existence of several disturbance regimes within the forest, controlling fine-scale pedodiversity.

show abstract

“…10 cm) canopy trees. A potential explanation for increased seedling diversity on sloped terrain is that steep slopes may be too unstable for large trees, which would mean that those areas are subject to a more rapidly cycling disturbance regime and a higher proportion of treefall gaps (Lobo and Dalling 2013). Upward concave terrain curvature is positively correlated with species richness, indicating that the hydrologic controls may be important to structuring the forest environment.…”

Section: Species Richness and Microtopographymentioning

confidence: 99%

Predicting spatial variations of tree species richness in tropical forests from high‐resolution remote sensing

Fricker

Wolf²,

Saatchi

et al. 2015

Ecological Applications

View full text Add to dashboard Cite

There is an increasing interest in identifying theories, empirical data sets, and remote-sensing metrics that can quantify tropical forest alpha diversity at a landscape scale. Quantifying patterns of tree species richness in the field is time consuming, especially in regions with over 100 tree species/ha. We examine species richness in a 50-ha plot in Barro Colorado Island in Panama and test if biophysical measurements of canopy reflectance from high-resolution satellite imagery and detailed vertical forest structure and topography from light detection and ranging (lidar) are associated with species richness across four tree size classes (>1, 1-10, >10, and >20 cm dbh) and three spatial scales (1, 0.25, and 0.04 ha). We use the 2010 tree inventory, including 204,757 individuals belonging to 301 species of freestanding woody plants or 166 ± 1.5 species/ha (mean ± SE), to compare with remote-sensing data. All remote-sensing metrics became less correlated with species richness as spatial resolution decreased from 1.0 ha to 0.04 ha and tree size increased from 1 cm to 20 cm dbh. When all stems with dbh > 1 cm in 1-ha plots were compared to remote-sensing metrics, standard deviation in canopy reflectance explained 13% of the variance in species richness. The standard deviations of canopy height and the topographic wetness index (TWI) derived from lidar were the best metrics to explain the spatial variance in species richness (15% and 24%, respectively). Using multiple regression models, we made predictions of species richness across Barro Colorado Island (BCI) at the 1-ha spatial scale for different tree size classes. We predicted variation in tree species richness among all plants (adjusted r² = 0.35) and trees with dbh > 10 cm (adjusted r² = 0.25). However, the best model results were for understory trees and shrubs (dbh 1-10 cm) (adjusted r² = 0.52) that comprise the majority of species richness in tropical forests. Our results indicate that high-resolution remote sensing can predict a large percentage of variance in species richness and potentially provide a framework to map and predict alpha diversity among trees in diverse tropical forests.

show abstract

Effects of topography, soil type and forest age on the frequency and size distribution of canopy gap disturbances in a tropical forest

Cited by 32 publications

References 42 publications

Landscape-scale changes in forest canopy structure across a partially logged tropical peat swamp

Landscape-scale changes in forest canopy structure across a partially logged tropical peat swamp

Disturbances can control fine-scale pedodiversity in old-growth forests: is the soil evolution theory disturbed as well?

Predicting spatial variations of tree species richness in tropical forests from high‐resolution remote sensing

Contact Info

Product

Resources

About