1
|
Chapman CA, Gogarten JF, Golooba M, Kalbitzer U, Omeja PA, Opito EA, Sarkar D. Fifty+ years of primate research illustrates complex drivers of abundance and increasing primate numbers. Am J Primatol 2023:e23577. [PMID: 37985837 DOI: 10.1002/ajp.23577] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2023] [Revised: 09/25/2023] [Accepted: 11/05/2023] [Indexed: 11/22/2023]
Abstract
Many primate populations are threatened by human actions and a central tool used for their protection is establishing protected areas. However, even if populations in such areas are protected from hunting and deforestation, they still may be threatened by factors such as climate change and its cascading impacts on habitat quality and disease dynamics. Here we provide a long-term and geographically wide-spread population assessment of the five common diurnal primates of Kibale National Park, Uganda. Over 7 year-long or longer census efforts that spanned 52 years, our team walked 1466 km, and recorded 480 monkey groups. Populations were generally relatively stable with a few exceptions, for which no apparent causative factors could be identified. This stability is unexpected as many ecological changes documented over the last 34+ years (e.g., decreasing food abundance and quality) were predicted to have negative impacts. Populations of some species declined at some sites but increased at others. This highlights the need for large, protected areas so that declines in particular areas are countered by gains in others. Kibale has large areas of regenerating forest and this most recent survey revealed that after 20+ years, forest regeneration in many of these areas appears sufficient to sustain sizeable primate populations, except for blue monkeys that have not colonized these areas. Indeed, the average primate abundance in the regenerating forest was only 8.1% lower than in neighboring old-growth forest. Thus, park-wide primate abundance has likely increased, despite many pressures on the park having risen; however, some areas in the park remain to be assessed. Our study suggests that the restoration, patrolling, and community outreach efforts of the Uganda Wildlife Authority and their partners have contributed significantly to protecting the park and its animals.
Collapse
Affiliation(s)
- Colin A Chapman
- Biology Department, Vancouver Island University, Nanaimo, British Columbia, Canada
- Wilson Center, Washington, District of Columbia, USA
- Shaanxi Key Laboratory for Animal Conservation, Northwest University, Xi'an, China
- School of Life Sciences, University of KwaZulu-Natal, Scottsville, Pietermaritzburg, South Africa
| | - Jan F Gogarten
- Helmholtz Institute for One Health, Greifswald, Germany
- Department of Applied Zoology and Nature Conservation, University of Greifswald, Greifswald, Germany
| | - Martin Golooba
- Makerere University Biological Field Station, Fort Portal, Uganda
| | - Urs Kalbitzer
- Department for the Ecology of Animal Societies, Max Planck Institute of Animal Behavior, Konstanz, Germany
- Department of Biology, University of Konstanz, Konstanz, Germany
| | - Patrick A Omeja
- Makerere University Biological Field Station, Fort Portal, Uganda
| | - Emmanuel A Opito
- Makerere University Biological Field Station, Fort Portal, Uganda
| | - Dipto Sarkar
- Department of Geography and Environmental Studies, Carleton University, Ottawa, Canada
| |
Collapse
|
2
|
Functional Traits and Local Environmental Conditions Determine Tropical Rain Forest Types at Microscale Level in Southern Ecuador. DIVERSITY 2023. [DOI: 10.3390/d15030420] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/18/2023]
Abstract
The main objective of this study was to determine the heterogeneity of tropical mountain rain forests along a micro-altitudinal gradient scale, integrating species functional traits in the separation of communities. To achieve this, a forest area of 13 ha in the Biological Reserve of San Francisco was monitored. First, we performed non-metric multidimensional analyses, and afterwards, we looked for correlations between plot altitude and characteristics of the forest (basal area, the number of species, the number of trees ≥20 cm diameter at breast height, per hectare, the forest canopy opening) were associated. To determine which characteristics significantly influence the separation of forest “communities”, we used a multivariate canonical correspondence analysis (CCA). Finally, we carried out the “Four Corners” analysis, combining abundance matrices, traits and environmental variables. We confirmed that the altitude and some associated characteristics are the key factors for the formation of two forest types. In addition, we determined that the inclusion of species functional traits confirms the separation of forest communities, and that elevation and its associated environmental variables function over relatively small areas and scales.
Collapse
|
3
|
Opito EA, Alanko T, Kalbitzer U, Nummelin M, Omeja P, Valtonen A, Chapman CA. 30 years brings changes to the arthropod community of Kibale National Park, Uganda. Biotropica 2023. [DOI: 10.1111/btp.13206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2023]
Affiliation(s)
| | | | - Urs Kalbitzer
- Department for the Ecology of Animal Societies Max Planck Institute of Animal Behavior Konstanz Germany
- Department of Biology University of Konstanz Konstanz Germany
| | - Matti Nummelin
- Faculty of Biological and Environmental Sciences University of Helsinki Helsinki Finland
| | - Patrick Omeja
- Makerere University Biological Field Station Fort Portal Uganda
| | - Anu Valtonen
- Department of Environmental and Biological Sciences University of Eastern Finland Joensuu Finland
| | - Colin A. Chapman
- Biology Department Vancouver Island University Nanaimo British Columbia Canada
- Department of Anthropology The George Washington University Washington District of Columbia USA
- School of Life Sciences University of KwaZulu‐Natal Scottsville, Pietermaritzburg South Africa
- Shaanxi Key Laboratory for Animal Conservation Northwest University Xi'an China
| |
Collapse
|
4
|
Recovery of Logged Tropical Montane Rainforests as Potential Habitats for Hainan Gibbon. FORESTS 2021. [DOI: 10.3390/f12060711] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
As the world’s rarest ape, the main threat facing Hainan gibbon (Nomascus hainanus) is habitat degradation and loss caused by human disturbances. The insufficient area and continuous human disturbance in most of the existing habitats can hardly maintain the future recovery and development of the gibbon population. A large area of secondary tropical montane rainforest in recovery was retained in Bawangling National Nature Reserve after disturbance. Therefore, it is of great significance to study the recovery of these secondary forests for the protection and restoration of Hainan gibbon habitat. To explore the recovery of secondary tropical rainforests after different disturbances, and whether they have the potential to serve as the future habitats for Hainan gibbon, we calculated four dynamic indexes (including recruitment rate, mortality/loss rate, relative growth rate and turnover rate) of abundance and basal area for the total community and for food plants of Hainan gibbon based on data from two censuses of secondary forests recovered nearly 45 years after different disturbances (clear-cutting and selective-logging) and old-growth forest of tropical montane rainforest. The results are as follows: (1) There were no significant differences in recruitment rates, mortality rates and turnover rates of abundance and basal area between recovered clear-cutting forests, selectively logged forests and old-growth forests. (2) Abundance, basal area and species of small (1 < DBH ≤ 10 cm) and medium (10 ≤ DBH < 30 cm) food plants in the two disturbed forests were higher, while those of large food plants (DBH ≥ 30 cm) in the two forests were lower than in old-growth forests. (3) For the common food species occurring in all three kinds of communities, the relative growth rate of most small trees in clear-cutting forest was higher than that of old-growth forest. Our research demonstrates that the lack of large food plants is the key limiting factor for the development of the secondary mountain rainforest as habitats for Hainan gibbon at present. However, it has great potential to transform into suitable habitats through targeted restoration and management due to the high recruitment rate and relative growth rate of the small- and medium-sized food plants.
Collapse
|
5
|
Functional Diversity Changes after Selective Thinning in a Tropical Mountain Forest in Southern Ecuador. DIVERSITY 2020. [DOI: 10.3390/d12060256] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background: The impact of selective thinning on forest diversity has been extensively studied in temperate and boreal regions. However, in the tropics, knowledge is still poor regarding the impacts of this silvicultural treatment on functional diversity, especially in tropical mountain forests, which are considered to be highly biodiverse ecosystems and also endangered by human activities. By evaluating the changes on functional diversity by using different indicators, hypothesizing that selective thinning significantly affects (directly or indirectly) tropical mountain forests, this work promotes sustainable ecosystem use. Methods: A total of 52 permanent plots of 2500 m2 each were installed in a primary mountain forest in the San Francisco Biological Reserve to assess the impact of this silvicultural treatment. Selective thinning can be defined as a controlled process, in which trees that compete with ecologically and/or valuable timber species are progressively removed to stimulate the development of profitable ones, called potential crop trees (PCT). In doing so, the best specimens remain in the forest stand until their final harvest. After PCT selection, 30 plots were chosen for the intervention, while 22 plots served as control plots. The thinning intensity fluctuated between 4 and 56 trees ha−1 (average 18.8 ± 12.1 stems ha−1). Functional Diversity (FD) indices, including the community weighted mean (CWM), were determined based on six traits using the FD package implemented in R software. The difference between initial and final conditions of functional richness (FRic), functional divergence (FDiv), functional evenness (FEve), functional dispersion (FDis), and Rao quadratic entropy (RaoQ) was modeled using linear mixed models (LMM). As fixed factors, we used all the predictors inherent to structural and ecological forest conditions before and after the selective thinning and as a random variable, we used the membership to nested sampling units. Results: Functional Richness (FRic) showed significant changes after selective thinning, the other indexes (FEve, FDis, FDiv, RaoQ) were only influenced by predictors related to ecological conditions and characteristics of the community.
Collapse
|
6
|
Quantifying Canopy Tree Loss and Gap Recovery in Tropical Forests under Low-Intensity Logging Using VHR Satellite Imagery and Airborne LiDAR. REMOTE SENSING 2019. [DOI: 10.3390/rs11070817] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Logging, including selective and illegal activities, is widespread, affecting the carbon cycle and the biodiversity of tropical forests. However, automated approaches using very high resolution (VHR) satellite data (≤ 1 m spatial resolution) to accurately track these small-scale human disturbances over large and remote areas are not readily available. The main constraint for performing this type of analysis is the lack of spatially accurate tree-scale validation data. In this study, we assessed the potential of VHR satellite imagery to detect canopy tree loss related to selective logging in closed-canopy tropical forests. To do this, we compared the tree loss detection capability of WorldView-2 and GeoEye-1 satellites with airborne LiDAR, which acquired pre- and post-logging data at the Jamari National Forest in the Brazilian Amazon. We found that logging drove changes in canopy height ranging from −5.6 to −42.2 m, with a mean reduction of −23.5 m. A simple LiDAR height difference threshold of −10 m was enough to map 97% of the logged trees. Compared to LiDAR, tree losses can be detected using VHR satellite imagery and a random forest (RF) model with an average precision of 64%, while mapping 60% of the total tree loss. Tree losses associated with large gap openings or tall trees were more successfully detected. In general, the most important remote sensing metrics for the RF model were standard deviation statistics, especially those extracted from the reflectance of the visible bands (R, G, B), and the shadow fraction. While most small canopy gaps closed within ~2 years, larger gaps could still be observed over a longer time. Nevertheless, the use of annual imagery is advised to reach acceptable detectability. Our study shows that VHR satellite imagery has the potential for monitoring the logging in tropical forests and detecting hotspots of natural disturbance with a low cost at the regional scale.
Collapse
|
7
|
Dynamics of Tropical Forest Twenty-Five Years after Experimental Logging in Central Amazon Mature Forest. FORESTS 2019. [DOI: 10.3390/f10020089] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Long-term studies of the dynamics of managed forests in tropical regions are lacking. This study aimed to evaluate the dynamics of a tropical forest, over a 25-year period, that was experimentally logged in 1987 and 1988 and submitted to three different cutting intensities. All trees with diameter at breast height (DBH) ≥ 10 cm have been measured annually since 1990. The three logging intensities that were applied were: light (T1)-trees harvested with DBH ≥ 55 cm; medium (T2)-DBH ≥ 50 cm; and heavy (T3)-DBH ≥ 40 cm. Control plots (T0) were also monitored. The highest mean annual mortality rates (1.82% ± 0.38), recruitment rates (2.93% ± 0.77) and diameter increments (0.30 ± 0.02 cm) occurred in the T3 treatment. Shifts in dynamics of the forest were mainly caused by a striking increase in a fast-growing pioneer species and their high mortality rates. The loss in stocking caused by mortality was greater than to that of replacement by recruitment. The results demonstrated that selective logging altered the natural dynamics of the forest through increased: mortality rates, recruitment and growth rates of the residual trees.
Collapse
|
8
|
Bowd EJ, Lindenmayer DB, Banks SC, Blair DP. Logging and fire regimes alter plant communities. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2018; 28:826-841. [PMID: 29411919 DOI: 10.1002/eap.1693] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2017] [Revised: 12/28/2017] [Accepted: 01/16/2018] [Indexed: 06/08/2023]
Abstract
Disturbances are key drivers of plant community composition, structure, and function. Plant functional traits, including life forms and reproductive strategies are critical to the resilience and resistance of plant communities in the event of disturbance. Climate change and increasing anthropogenic disturbance are altering natural disturbance regimes globally. When these regimes shift beyond the adaptive resilience of plant functional traits, local populations and ecosystem functions can become compromised. We tested the influence of multiple disturbances, of varying intensity and frequency, on the composition and abundance of vascular plant communities and their respective functional traits (life forms and reproductive strategies) in the wet sclerophyll, Mountain Ash Eucalyptus regnans forests of southeastern Australia. Specifically, we quantified the effect of the type and number of disturbances (including fires, clearcut logging, and salvage logging) on plant community composition. We found that clearcut and salvage logging and the number of fires significantly influenced plant community composition and functional traits. Specifically, multiple fires resulted in lower populations of species that depend on on-site seeding for persistence. This includes the common tree species Eucalyptus regnans, Pomaderris aspera, and Acacia dealbata. In contrast, clearcut and salvage logged sites supported abundant on-site seeder species. However, species that depend on resprouting by surviving individuals, such as common and keystone "tree ferns" Dicksonia antarctica and Cyathea australis, declined significantly. Our data have important implications for understanding the relationship between altered disturbance regimes and plant communities and the respective effects on ecosystem function. In a period of rapid global environmental change, with disturbances predicted to increase and intensify, it is critical to address the impact of altered disturbance regimes on biodiversity.
Collapse
Affiliation(s)
- Elle J Bowd
- Fenner School of Environment and Society, The Australian National University, Canberra, Australian Capital Territory, 2601, Australia
| | - David B Lindenmayer
- Fenner School of Environment and Society, The Australian National University, Canberra, Australian Capital Territory, 2601, Australia
| | - Sam C Banks
- Fenner School of Environment and Society, The Australian National University, Canberra, Australian Capital Territory, 2601, Australia
| | - David P Blair
- Fenner School of Environment and Society, The Australian National University, Canberra, Australian Capital Territory, 2601, Australia
| |
Collapse
|
9
|
Wu C, Vellend M, Yuan W, Jiang B, Liu J, Shen A, Liu J, Zhu J, Yu M. Patterns and determinants of plant biodiversity in non-commercial forests of eastern China. PLoS One 2017; 12:e0188409. [PMID: 29161324 PMCID: PMC5697849 DOI: 10.1371/journal.pone.0188409] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Accepted: 11/06/2017] [Indexed: 11/18/2022] Open
Abstract
Non-commercial forests represent important habitats for the maintenance of biodiversity and ecosystem function in China, yet no studies have explored the patterns and determinants of plant biodiversity in these human dominated landscapes. Here we test the influence of (1) forest type (pine, mixed, and broad-leaved), (2) disturbance history, and (3) environmental factors, on tree species richness and composition in 600 study plots in eastern China. In total, we found 143 species in 53 families of woody plants, with a number of species rare and endemic in the study region. Species richness in mixed forest and broad-leaved forest was higher than that in pine forest, and was higher in forests with less disturbance. Species composition was influenced by environment factors in different ways in different forest types, with important variables including elevation, soil depth and aspect. Surprisingly, we found little effect of forest age after disturbance on species composition. Most non-commercial forests in this region are dominated by species poor pine forests and mixed young forests. As such, our results highlight the importance of broad-leaved forests for regional plant biodiversity conservation. To increase the representation of broad-leaved non-commercial forests, specific management practices such as thinning of pine trees could be undertaken.
Collapse
Affiliation(s)
- Chuping Wu
- College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang, China
- Zhejiang Academy of Forestry, Hangzhou, Zhejiang, China
| | - Mark Vellend
- Departement de biologie, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Weigao Yuan
- Zhejiang Academy of Forestry, Hangzhou, Zhejiang, China
| | - Bo Jiang
- Zhejiang Academy of Forestry, Hangzhou, Zhejiang, China
| | - Jiajia Liu
- College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang, China
| | - Aihua Shen
- Zhejiang Academy of Forestry, Hangzhou, Zhejiang, China
| | - Jinliang Liu
- College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang, China
| | - Jinru Zhu
- Zhejiang Academy of Forestry, Hangzhou, Zhejiang, China
| | - Mingjian Yu
- College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang, China
- * E-mail:
| |
Collapse
|