Registered users receive a variety of benefits including the ability to customize email alerts, create favorite journals list, and save searches.
Please note that a BioOne web account does not automatically grant access to full-text content. An institutional or society member subscription is required to view non-Open Access content.
Contact helpdesk@bioone.org with any questions.
Restoration of degraded tropical forests can enhance ecosystem service provisioning, improve habitat quality for tropical forest biota and generate income from timber and NTFPs. In Indonesia alone, an estimated 25 million ha of former logging concessions are without current management, representing a huge opportunity for biodiversity conservation. However, currently such forests are typically converted to plantations. Realising the restoration potential of these forests will require viable business models that couple restoration goals with income generation. Unfortunately, understanding of natural succession trajectories and cost-effectiveness of restoration interventions remains poor. We present an overview of research, including three planned experiments designed to test the economic viability of large-scale restoration treatments, in a former logging concession at Harapan Rainforest (98,455 ha), Indonesia. These experiments will address the following questions: (1) Can the selective removal of pioneer trees, including an invasive species, be used to accelerate succession; (2) how does the functional diversity of the planted matrix affect growth and survival of a high value target species; and (3) how does seed density affect recruitment success in direct seeding treatments? Treatments will be applied to large compartments (4~8 ha) to reduce edge effects and simplify management. Monitoring plots (20 × 20 m × 5 reps) within each compartment will be used to assess silvicultural responses, while changes in biodiversity and carbon storage will be monitored at the compartment level. The large spatial scale and high replication of the treatments will establish an experimental platform that will inform many different aspects of tropical forest ecology.
An estimated 63% of Southeast Asian forests are classed as disturbed and secondary as a result of human activity. Many of these forests remain important for biodiversity conservation and ecosystem services so there is much interest in their capacity for restoration. The role of larger animals as seed dispersers in natural regeneration is well-attested since they are often the only agent by which large-seeded trees can effectively disperse. This is especially important for late successional shade-tolerant species which might otherwise be excluded from disturbed sites. However, many larger animals are sensitive to habitat degradation so may be lost from the very areas that require them. We investigated the persistence of a suite of large mammals that are known seed-dispersers and are also threatened species, in a degraded site in lowland south-central Sumatra. We used camera traps and field observations to relate their distributions to prevailing vegetation conditions. Although most species were more frequently detected in the more intact areas, most were able to occupy habitats with high levels of disturbance and population densities were relatively high. It is clear that severe habitat degradation does not necessarily lead to the immediate loss of large-bodied seed dispersers, so ensuring adequate protection for these species from external threats, such as hunting, must be built into management plans for restoration concessions.
A short description of how the Harapan Rainforest may have been before logging is given, based upon interviews with the people who conducted surveys prior to timber extraction. This information is used to demonstrate similarity to the forests of the Pasir Mayang and Muara Bungo area, which have been more thoroughly surveyed. The former state is then contrasted with the current condition based upon botanical surveys undertaken in 2008, 2012 and 2013, highlighting both dominant and rare species as well as the need for more comprehensive information on the conservation status of the majority of species. Finally, a number of introduced weedy species are now present whose potential for continued population growth and potential to retard restoration is discussed.
Artificial ponds and swamps commonly occur throughout logged forests of Southeast Asia in association with roads. Dammed streams accumulate water, which floods the surrounding forest creating ponds and swamps, which are slow to recover to a condition that maximises their conservation value. In particular, ponds remain relatively anoxic and the self-recovery of swamps is slow due to delayed colonisation by swamp tolerant species. The Harapan Rainforest ecosystem restoration concession in Sumatra is a clear example of this issue. Within the 100,000 ha of lowland rain forest, four watersheds are present with more than 750 km of rivers and their tributaries. Across this area more than 175 artificial ponds and swamps have been created through the construction of the road network over the past 30–40 years. Despite the artificial nature of their creation there is a significant conservation value in improving the alluvial swamps due to the significant decline in extent of this habitat across Southeast Asia. However, tropical forest streams too have been widely degraded and are a conservation priority due to the uniqueness of their associated biodiversity. As such, we propose the restoration of these habitats through the drainage of ponds to improve stream flow and connectivity and the establishment of swamp specialist tree species. An approach for identifying sites suitable for restoration is presented focusing on making comparisons with ‘model’ streams and swamps. Restoration techniques are proposed, including a list of swamp species suitable for planting trials at swamp sites and techniques for the suppression of disturbance responsive species, such as bamboos, ferns and lianas. We stress that pond restoration activities in general should always include unmanaged control ponds to enable the measurement of the additional benefit of restoration activities beyond that of natural recovery.
Gunung Palung National Park in West Kalimantan, Indonesia has been persistently threatened by illegal logging for the past several decades. Subsequent fires have led to the encroachment of noxious grasses such as Imperata cylindrica, which have arrested succession to secondary forest within and around the park. Since 2009, local NGO Alam Sehat Lestari (ASRI) has reforested 20 hectares of degraded Imperata grassland within the park, with the goal of restoring forest area and decreasing the incidence of illegal logging inside the park by providing jobs and income to local people. In February 2013, a survey was conducted to assess the social impacts of the reforestation program, and to test the hypothesis that participation in reforestation can reduce instances of illegal logging through two pathways: (1) economic improvement for participants; (2) altering perceptions towards illegal logging. Structured interviews were conducted with 50 local residents, one-third of which identified as former illegal loggers, to gauge their perceptions towards forest conservation and illegal logging. The survey found that 80% of respondents believed that the reforestation program helped to reduce illegal logging in the park. However, the pathways through which this change occurred were different from those hypothesized. There was little evidence supporting the “perceptions change” pathway, but greater evidence supporting the “economic improvement” pathway through the medium of skill-building rather than direct economic improvement. Approximately 50% of participants reported engaging in self-directed tree planting activities post-involvement. These results suggest that forest restoration can effectively be used as a community-engagement tool to address illegal logging.
The intensification of agricultural activity can have profound impacts on biodiversity. We evaluated the influence of the landscape's percentage of forest cover and shaded cocoa plantations on the community of zoochorous bromeliads in southern Bahia, Brazil. We selected two contrasting landscapes, one dominated by Atlantic tropical rainforest and the other by traditional cocoa plantations. In each landscape we sampled three forest fragments and three areas of cocoa plantation, where we conducted a survey of epiphytic bromeliads of the genera Aechmea and Hohenbergia in eight plots of 400 m2 in each area. The number of trees differed between landscapes and habitats, and was higher in forest fragments than in shade cocoa plantations, but the number of phorophytes was similar between landscapes and habitats. Highest richness of Aechmea and Hohenbergia species was found in forest fragments in landscapes where forests are predominant. Contrary to expectations, the richness in the other areas was relatively low, and extremely low in the landscape dominated by cocoa plantations, ranging from zero to four species per fragment. Bromeliad abundance was not different among landscapes and habitats, but the shade cocoa plantations located in predominant agroforest landscape showed the higher number of stands. Moreover, the species found in the cocoa plantations were more drought-tolerant species. These results suggest that the conservation of species of these genera depends on factors such as the conservation status of each forest fragment and the microclimatic alterations in the habitats, and not only on the percentage of forest in the landscape per se.
Tropical dry forests (TDF) in Mesoamerica are highly endangered by the expansion of human activities (e.g., agriculture and cattle ranching). In contrast, TDF in Costa Rica have experienced outstanding restoration due to changes in economic and conservation policies. Currently TDF landscapes in Costa Rica are a mosaic of different successional stages. Tree breeding systems and pollination and dispersal syndromes are key elements for understanding restoration processes in TDFs. In this study we describe and compare tree species composition and diversity in three TDF successional stages (early, intermediate and late) in Guanacaste, Costa Rica. We describe for the first time tree species breeding systems and pollination and dispersal syndromes for the largest and most significant TDF remnant in Mesoamerica. We set up nine plots, three per successional stage, and we measured and identified 1,072 trees from 96 species. Species richness and diversity indices were higher for the intermediate stage. Monoecy was the most common breeding system, as in other tropical life zones. Insects were the dominant pollinators, facilitated by the trees' small inflorescences. Wind was found to be not only the next most influential pollinator, mainly in open and disturbed early forests, but also it was also a good seed dispersal agent. As TDF age increases so does the relevancy of birds and mammals as dispersers; the late stage therefore has more tree species with adaptations to these dispersers.
Côte d'Ivoire is the world's leading cocoa producer, annually generating over 1,500,000 metric tons of Theobroma cacao beans. Growth of this agri-business has led to extensive deforestation in Côte d'Ivoire, where the majority of the country's forest (excluding that in Tai National Park) exists as small, fragmented forest islands. Most of these forest blocks are designated as national parks or forest reserves, i.e., protected areas (PAs), but wildlife within Côte d'Ivoire's PAs is increasingly threatened by two illegal activities: hunting and full sun cocoa farming. In this paper, we investigate the impact of cocoa production on primate populations inside protected areas. We surveyed twenty three PAs (5 national parks, 18 forest reserves) in Côte d'Ivoire to determine (1) the number of primate taxa present, (2) the number of human inhabitants living adjacent to or within each PA, (3) the extent of overall habitat degradation, and (4) the extent of habitat degradation due to cocoa farming. Our data reveal a significant positive correlation (r2 = .736, p < .01, α = 0.01) between cocoa farming and the absence of primate species inside Côte d'Ivoire's national parks and forest reserves. Thirteen of 23 protected areas surveyed have lost all primate populations, and four taxa - Colobus vellerosus (white-thighed black and white colobus), Colobus polykomos (Western black and white colobus), Procolobus badius waldroni (Miss Waldron's red colobus) and Procolobus badius badius (Bay colobus) – were not found in any PAs we visited. Aggressive conservation action is needed to curb hunting throughout Côte d'Ivoire, but unless illegal cocoa farming is similarly controlled, even effective enforcement of anti-hunting laws will not prevent the loss of additional primate diversity, since habitats capable of supporting primate populations – including those within protected areas - will no longer exist.
The fern and lycophyte flora of Mexico contains 13 species in the genus Phlegmariurus (Lycopodiaceae; club moss family), of which nine are found in the state of Veracruz (P. cuernavacensis, P. dichotomus, P. linifolius, P. myrsinites, P. orizabae, P. pithyoides, P. pringlei, P. reflexus, P. taxifolius). They are located primarily in undisturbed areas of humid montane, pine-oak and tropical humid forests, which are all ecosystems threatened by deforestation and fragmentation. The objective of this study was to evaluate and understand the distribution and conservation status of species of this genus in the state of Veracruz, Mexico. Using Maxent, probability distributions were modeled based on 173 herbarium specimens (25% from recent collections by the authors and/or collaborators), considering factors such as climate, elevation and vegetation cover. Additionally, anthropogenic impacts on the original habitat of each species were analyzed in order to assign threatened categories based on IUCN classifications at regional levels. Results show that potential distributions are located in the montane regions of the central and southern parts of the state. All nine Phlegmariurus species in Veracruz were found to be in some category of risk, with P. orizabae classified as critically endangered, having only a single specimen collected in 1854. The main reasons for species threats are the continuous loss and fragmentation of their natural habitat, uncontrolled harvesting activities, and the lack of protected areas that include humid montane and pine-oak forests in the central region of the state.
Informed conservation decision-making requires meaningful biodiversity assessment, yet performing an inventory of all species present at a site is an impossibility. A small group of species is frequently used as a proxy for “total” biodiversity, and various attributes required by bioindicator groups have been suggested. We synthesized these suggestions as four key criteria: i) tractable taxonomy, ii) easily surveyed, iii) broadly distributed higher taxa but specialized species, and iv) diversity patterns reflected in other groups; and compare three groups - bats, beetles and butterflies - against these criteria to evaluate their potential as bioindicators in Malaysia. DNA barcodes from butterflies, bats and beetles sampled during standardized surveys at Rimba Ilmu Botanic Garden and Ulu Gombak Forest Reserve were sorted into molecular operational taxonomic units (MOTU) and assigned species and family names. Beetle and butterfly sampling required a similar number of person-hours per species, which was an order of magnitude lower than that required for bat sampling. It was easier to generate DNA barcodes for butterflies and bats than for beetles and the number of MOTU assigned a species and/or family name was higher for butterflies and bats (>82%) than for beetles. Most butterfly and bat families were found at both sites but the species of all three groups showed little overlap between sites (<15%). The species richnesses of all three groups were correlated with each other, but only bat and butterfly species richness was strongly correlated and statistically significant. Based on the four criteria, butterflies showed greatest potential as bioindicators.
Habitat loss is one of the main factors reducing wildlife diversity and restricting its conservation. Habitat suitability models are important tools for wildlife management and conservation in order to evaluate the impacts of human activities on wildlife habitats. The capybara (Hydrochoerus hydrochaeris) is a semi-aquatic rodent that lives in South American wetlands that are subject to heavy human use. A spatially explicit model of capybara's Potential Habitat Suitability (PHS) was developed for the core area of its distribution in the humid subtropical region of Argentina. Predictive variables in this deductive model were related to capybara habitat requirements, and their values were obtained from existing published papers. The PHS model was performed using two data subsets that evaluated both ecological requirements and anthropogenic threats, resulting in two partial indices: Potential Ecological Suitability (PES), and Risk of Human Impact (RHI). The PES assesses vegetation cover and the presence of lentic and lotic freshwater bodies. The RHI estimates habitat fragmentation and accessibility of poachers. Variables for the habitat requirements were spatially expressed through Geographic Information Systems. The model accuracy assessment was performed through field work and achieved 72% of overall accuracy. Results indicate that 13% of the study area had the highest values of PHS index, characterized by the presence of vast wetlands, habitats with low fragmentation and low accessibility for poachers. These results are a useful tool to improve conservation and management programs for protection of capybara habitat.
The yellow tailed woolly monkey (Lagothrix flavicauda) is one of the world's most threatened primate species. It is endemic to a small area of montane forest in northern Peru, an area with high immigration and deforestation rates. Since 2007, community conservation actions have been implemented in the area of Yambrasbamba, a farming community in Amazonas department. These actions included the signing of voluntary pledges by local villagers to control hunting and forest clearance. A first population density survey was carried out in 2008/9, shortly after the implementation of these pledges; a second survey in the same area that replicated the methods used in the previous survey was carried out in 2012/13. Using transect width estimation from line transects and a Normalized Difference Vegetative Index (NDVI) from satellite images, we compared population density and deforestation rates between surveys. Results showed an increase in the L. flavicauda population at the study site, with significant increases in densities of infant (P <0.001) and juvenile individuals (P = 0.019). This suggests that increases are from natural population growth rather than the in-migration of groups or individuals from outlying areas. The NDVI showed low levels of deforestation still occurring in the area, but at a lower rate than the regional and national averages. Our results provide compelling evidence that Community Conservation projects can be successful in highly populated areas, and we urge conservation practitioners to involve local actors when planning and implementing initiatives.
Conversion from timber-dominated forestry to forest ecosystem management needs a rational management intensity to manage forest structure, which should be decided upon by managers and scientists as well as stakeholders. However, few studies have attempted to quantify optimal silvicultural measures for forest management intensity. Here, we examined the short-term effect of light and heavy management intensities on structure dynamics (tree composition, diversity, volumes and slenderness) in monoculture forests of southern subtropical China. Species diversity was generally lower in the heavy-intensity forests than in the light-intensity forests. The range in diameters was larger in the logged forest compared to control ones. The stand volume varied greatly between management intensities. Though higher trunk slenderness value (>80) indicates higher susceptibility to meteorological disturbance such as wind storm and heavy snow, trunk slenderness in the control and the heavy-intensity plots increased significantly compared to that in the light-intensity plot. These results suggest that stand structure dynamic are influenced by different management intensities. We conclude that light-intensity management enhances the richness and affects their patterns of diversity, and heavy-intensity management promotes an increase in understory diversity and regeneration but deficits in volumes and basal areas. In summary, we provide insights beyond traditional studies on different management intensities and levers to sustainable development of forestry. Our study also emphasises the importance for forest managers' understanding between management and conservation of monoculture forest. Nevertheless, variation in structure response to management intensity calls for careful consideration in future strategies, not only of which structure to favor during operations, but also, of how the treatments are applied.
Asian tropical forests are under extreme stress from clearance, fragmentation, and logging. Because Singapore suffered these same impacts in the 19th century, it can act as an early warning system for the region. We identified invasive exotic tree species from a comprehensive survey, assessed their survival and growth in the open and under a forest canopy, and compared their traits with native pioneers and widely planted exotic species that have failed to naturalize. Nine species were invasive: Acacia auriculiformis (ear-leaf acacia), Cecropia pachystachya (trumpet tree), Falcataria moluccana (Moluccan albizia), Leucaena leucocephala (leucaena), Manihot carthaginensis subp. glaziovii (Ceara rubber tree), Muntingia calabura (Jamaican cherry tree), Piper aduncum (spiked pepper), Pipturus argenteus (white mulberry), and Spathodea campanulata (African tulip tree). Under the forest canopy, all grew little and suffered high (75–100%) mortality, with Spathodea surviving best. At the open site, mortality was low (0–25%) and height growth rapid (1.6–8.6 cm wk−1), with Leucaena growing fastest. The only significant trait difference between native pioneer trees and invasive exotics was the dispersal syndrome; none of the common native pioneers are wind dispersed, while two invasive species are. Among exotics, there were highly significant differences between invasive and non-invasive species in wood density and seed size, with invasive species having only 54% of the mean wood density and 19% of the dry seed mass of non-invasive species. Invasive exotics were also significantly farther from their native ranges than non-invasive species. None of these invasive tree species is a direct threat to the integrity of native closed-canopy forest, but they dominate on newly abandoned land and may pre-empt the recovery of native forest on such sites.
Among different approaches to exploring and describing the ecological complexity of natural environments, soundscape analyses have recently provided useful proxies for understanding and interpreting dynamic patterns and processes in a landscape. Nevertheless, the study of soundscapes remains a new field with no internationally accepted protocols. This work provides the first guidelines for monitoring soundscapes in three different tropical areas, specifically located in the Atlantic Forest, Rupestrian fields, and the Cerrado (Brazil). Each area was investigated using three autonomous devices recording for six entire days during a period of 15 days in both the wet and dry seasons. The recordings were processed via a specific acoustic index and successively subsampled in different ways to determine the degree of information loss when reducing the number of minutes of recording used in the analyses. We describe for the first time the temporal and spectral soundscape features of three tropical environments. We test diverse programming routines to describe the costs and the benefits of different sampling designs, considering the pressing issue of storing and analyzing extensive data sets generated by passive acoustic monitoring. Schedule 5 (recording one minute of every five) appeared to retain most of the information contained in the continuous recordings from all the study areas. Less dense recording schedules produced a similar level of information only in specific portions of the day. Substantial sampling protocols such as those presented here will be useful to researchers and wildlife managers, as they will reduce time- and resource-consuming analyses, whilst still achieving reliable results.
Teak (Tectona grandis), which is among the most valuable tropical timber species, is under pressure from rapid deforestation and habitat fragmentation. Limited genetic information is available for Myanmar teak, which comes from the largest natural teak-bearing forest area in the world. To determine the phylogeographic patterns of Myanmar teak, we evaluated three newly developed chloroplast single nucleotide polymorphism (cpSNP) and 10 nuclear simple sequence repeat (nrSSR) markers in 480 individuals representing 20 natural populations. The cpSNP markers detected four haplotypes, each differing by a single mutation. The GST value was lower than the NST value and did not reveal a phylogeographic structure of Myanmar teak. Nuclear microsatellite analysis revealed high genetic diversity with the mean expected heterozygosity (0.652). The same level of genetic differentiation (4%) was observed for both cpSNP and nrSSR markers in different groups. Conservation of the HMB, TDG, KTA, and POL populations should receive highest priority because these contribute most to the total genetic diversity. The genetic boundaries of teak observed from combining the results of cpSNP and nrSSR marker barriers suggested four potential zones in the teak seed transfer guidelines of Myanmar. In light of our findings, we discussed appropriate gene conservation strategies and proposed seed zones to safeguard the current genetic resources of Myanmar teak.
Can the strategic incorporation of lianas (woody vines) into rainforest restoration plantings enhance biodiversity-conservation outcomes? Lianas are an integral component of primary tropical rainforests yet are often omitted from rainforest restoration plantings as they may damage trees and compete with them for resources. However, there is increasing evidence that many ecological and physiognomic characteristics of lianas may be of some value to restoration plantings, at least in certain contexts. We propose strategies for experimentally incorporating lianas into rainforest-restoration plantings to explore whether they can expedite rainforest establishment and enhance biodiversity-conservation outcomes.
We assessed land cover and land use change in Driefontein Grasslands Important Bird Area (Driefontein IBA), Zimbabwe, after the land reforms that took place in 2000, using remotely sensed satellite land cover images of 1995, 2000, 2005 and 2010. A drive transect was done for ground truthing. Data were analysed spatially in a Geographical Information System environment. Changes in land cover and land use proportions were recorded from 1995 to 2010 throughout the Driefontein IBA. The land cover classes of grassland and wetland showed a decrease, whereas land area under cultivation increased during 1995–2010. However, the woodland area marginally remained constant over the same time. We concluded that changes in land cover in the study area were largely driven by land use change, i.e., increase in cultivation, following the resettlement of people within the Driefontein IBA. It is likely that with increasing human population the natural habitat of the study area will be degraded further, negatively impacting key sensitive habitats such as wetlands, bird species, and other biodiversity. Threats to birds and wetlands habitats are also threats to human livelihoods because people in this semi-arid area depend on wetland ecosystem services for their survival. The study recommends continuous monitoring of Driefontein IBA for conservation of birds and their habitats.
This article is only available to subscribers. It is not available for individual sale.
Access to the requested content is limited to institutions that have
purchased or subscribe to this BioOne eBook Collection. You are receiving
this notice because your organization may not have this eBook access.*
*Shibboleth/Open Athens users-please
sign in
to access your institution's subscriptions.
Additional information about institution subscriptions can be foundhere