Intact Forest in Selective Logging Landscapes in the Tropics

Logging activities degrade forest habitats across large areas of the tropics, but the impacts on trophic interactions that underpin forest ecosystems are poorly understood. DNA metabarcoding provides an invaluable tool to investigate such interactions, allowing analysis at a far greater scale and resolution than has previously been possible. We analysed the diet of the insectivorous fawn leaf-nosed bat Hipposideros cervinus across a forest disturbance gradient in Borneo, using a dataset of ecological interactions from an unprecedented number of bat-derived faecal samples. Bats predominantly consumed insects from the orders Lepidoptera, Blattodea, Diptera and Coleoptera, and the taxonomic composition of their diet remained relatively consistent across sites regardless of logging disturbance. There was little difference in the richness of prey consumed in each logging treatment, indicating potential resilience of this species to habitat degradation. In fact, bats consumed a high richness of prey items, and intensive sampling is needed to reliably compare feeding ecology over multiple sites regardless of the bioinformatic procedures used.

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Using Landsat time series imagery to detect forest disturbance in selectively logged tropical forests in Myanmar

Canadian Journal of Forest Research ◽

10.1139/cjfr-2016-0244 ◽

2017 ◽

Vol 47 (3) ◽

pp. 289-296 ◽

Cited By ~ 16

Author(s):

Katsuto Shimizu ◽

Raul Ponce-Hernandez ◽

Oumer S. Ahmed ◽

Tetsuji Ota ◽

Zar Chi Win ◽

...

Keyword(s):

Time Series ◽

Forest Disturbance ◽

Landsat Imagery ◽

Forest Degradation ◽

Selective Logging ◽

Mitigation Strategies ◽

Forest Disturbances ◽

The Tropics ◽

Degradation Indicator ◽

Disturbance Detection

Detecting forest disturbances is an important task in formulating mitigation strategies for deforestation and forest degradation in the tropics. Our study investigated the use of Landsat time series imagery combined with a trajectory-based analysis for detecting forest disturbances resulting exclusively from selective logging in Myanmar. Selective logging was the only forest disturbance and degradation indicator used in this study as a causative force, and the results showed that the overall accuracy for forest disturbance detection based on selective logging was 83.0% in the study area. The areas affected by selective logging and other factors accounted for 4.7% and 5.4%, respectively, of the study area from 2000 to 2014. The detected disturbance areas were underestimated according to error assessments; however, a significant correlation between areas of disturbance and numbers of harvested trees during the logging year was observed, indicating the utility of a trajectory-based, annual Landsat imagery time series analysis for selective logging detection in the tropics. A major constraint of this study was the lack of available data for disturbances other than selective logging. Further studies should focus on identifying other types of disturbances and their impacts on future forest conditions.

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Carbon Dynamics in a Human-Modified Tropical Forest: A Case Study Using Multi-Temporal LiDAR Data

Remote Sensing ◽

10.3390/rs12030430 ◽

2020 ◽

Vol 12 (3) ◽

pp. 430 ◽

Cited By ~ 2

Author(s):

Yhasmin Mendes de Moura ◽

Heiko Balzter ◽

Lênio S. Galvão ◽

Ricardo Dalagnol ◽

Fernando Espírito-Santo ◽

...

Keyword(s):

Carbon Cycle ◽

Tropical Forests ◽

Carbon Dynamics ◽

Carbon Stocks ◽

Forest Carbon ◽

Selective Logging ◽

Carbon Accounting ◽

Lidar Data ◽

Multi Temporal ◽

The Tropics

Tropical forests hold significant amounts of carbon and play a critical role on Earth´s climate system. To date, carbon dynamics over tropical forests have been poorly assessed, especially over vast areas of the tropics that have been affected by some type of disturbance (e.g., selective logging, understory fires, and fragmentation). Understanding the multi-temporal dynamics of carbon stocks over human-modified tropical forests (HMTF) is crucial to close the carbon cycle balance in the tropics. Here, we used multi-temporal and high-spatial resolution airborne LiDAR data to quantify rates of carbon dynamics over a large patch of HMTF in eastern Amazon, Brazil. We described a robust approach to monitor changes in aboveground forest carbon stocks between 2012 and 2018. Our results showed that this particular HMTF lost 0.57 m·yr−1 in mean forest canopy height and 1.38 Mg·C·ha−1·yr−1 of forest carbon between 2012 and 2018. LiDAR-based estimates of Aboveground Carbon Density (ACD) showed progressive loss through the years, from 77.9 Mg·C·ha−1 in 2012 to 53.1 Mg·C·ha−1 in 2018, thus a decrease of 31.8%. Rates of carbon stock changes were negative for all time intervals analyzed, yielding average annual carbon loss rates of −1.34 Mg·C·ha−1·yr−1. This suggests that this HMTF is acting more as a source of carbon than a sink, having great negative implications for carbon emission scenarios in tropical forests. Although more studies of forest dynamics in HMTFs are necessary to reduce the current remaining uncertainties in the carbon cycle, our results highlight the persistent effects of carbon losses for the study area. HMTFs are likely to expand across the Amazon in the near future. The resultant carbon source conditions, directly associated with disturbances, may be essential when considering climate projections and carbon accounting methods.

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Resilience of terrestrial mammals to logging in an active concession in Sarawak, Borneo

Mammalia ◽

10.1515/mammalia-2020-0011 ◽

2020 ◽

Vol 0 (0) ◽

Author(s):

Marius Joscha Maiwald ◽

Jayasilan Mohd-Azlan ◽

Jedediah F. Brodie

Keyword(s):

Species Richness ◽

Activity Patterns ◽

Selective Logging ◽

Diel Activity ◽

Individual Species ◽

Terrestrial Mammals ◽

The Tropics ◽

Reduced Impact Logging ◽

Malaysian Borneo

AbstractSelective logging is very widespread across the tropics and can alter the habitat for myriad wildlife species. But while many studies have assessed the impacts of past logging on forest animals, far fewer have investigated how species respond to logging while the timber operations are actually going on. This is an important knowledge gap because, considering the prevalence of logging across the world, numerous areas will be undergoing active extraction at any given time. We compared the occurrence and diel activity patterns of individual species of medium- to large-bodied terrestrial mammals, as well as the richness of the entire assemblage, among sites that were either unlogged, had been logged historically, or had ongoing ‘reduced impact’ timber extraction in the Kapit Region of Sarawak, Malaysian Borneo. We found no significant differences in estimated occupancy or activity patterns of particular species, or in overall species richness, among logging treatments. Across sites, species richness in this area appeared to be as high as or higher than in many other parts of the state, including some protected areas. Though monitoring is needed to assess potential long-term impacts, our results suggest that reduced-impact logging could allow economic development that is sustainable for many wildlife populations.

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Avian responses to selective logging shaped by species traits and logging practices

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2015.0164 ◽

2015 ◽

Vol 282 (1808) ◽

pp. 20150164 ◽

Cited By ~ 39

Author(s):

Zuzana Burivalova ◽

Tien Ming Lee ◽

Xingli Giam ◽

Çağan Hakkı Şekercioğlu ◽

David S. Wilcove ◽

...

Keyword(s):

Management Strategies ◽

Bird Species ◽

Timber Harvest ◽

Species Traits ◽

Selective Logging ◽

Species Response ◽

Feeding Group ◽

Avian Biodiversity ◽

Forest Use ◽

The Tropics

Selective logging is one of the most common forms of forest use in the tropics. Although the effects of selective logging on biodiversity have been widely studied, there is little agreement on the relationship between life-history traits and tolerance to logging. In this study, we assessed how species traits and logging practices combine to determine species responses to selective logging, based on over 4000 observations of the responses of nearly 1000 bird species to selective logging across the tropics. Our analysis shows that species traits, such as feeding group and body mass, and logging practices, such as time since logging and logging intensity, interact to influence a species' response to logging. Frugivores and insectivores were most adversely affected by logging and declined further with increasing logging intensity. Nectarivores and granivores responded positively to selective logging for the first two decades, after which their abundances decrease below pre-logging levels. Larger species of omnivores and granivores responded more positively to selective logging than smaller species from either feeding group, whereas this effect of body size was reversed for carnivores, herbivores, frugivores and insectivores. Most importantly, species most negatively impacted by selective logging had not recovered approximately 40 years after logging cessation. We conclude that selective timber harvest has the potential to cause large and long-lasting changes in avian biodiversity. However, our results suggest that the impacts can be mitigated to a certain extent through specific forest management strategies such as lengthening the rotation cycle and implementing reduced impact logging.

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