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Featured researches published by Robert Nasi.


International Forestry Review | 2011

Empty forests, empty stomachs? Bushmeat and livelihoods in the Congo and Amazon Basins

Robert Nasi; A. Taber; N. Van Vliet

SUMMARY Protein from forest wildlife is crucial to rural food security and livelihoods across the tropics. The harvest of animals such as tapir, duikers, deer, pigs, peccaries, primates and larger rodents, birds and reptiles provides benefits to local people worth millions of USS annually and represents around 6 million tonnes of animals extracted yearly. Vulnerability to hunting varies, with some species sustaining populations in heavily hunted secondary habitats, while others require intact forests with minimal harvesting to maintain healthy populations. Some species or groups have been characterized as ecosystem engineers and ecological keystone species. They affect plant distribution and structure ecosystems, through seed dispersal and predation, grazing, browsing, rooting and other mechanisms. Global attention has been drawn to their loss through debates regarding bushmeat, the “empty forest” syndrome and their ecological importance. However, information on the harvest remains fragmentary, along with understanding of ecological, socioeconomic and cultural dimensions. Here we assess the consequences, both for ecosystems and local livelihoods, of the loss of these species in the Amazon and Congo basins.


PLOS ONE | 2014

Four decades of forest persistence, clearance and logging on Borneo

David Gaveau; Sean Sloan; Elis Molidena; Husna Yaen; Doug Sheil; Nicola K. Abram; Marc Ancrenaz; Robert Nasi; Marcela Quinones; Niels Wielaard; Erik Meijaard

The native forests of Borneo have been impacted by selective logging, fire, and conversion to plantations at unprecedented scales since industrial-scale extractive industries began in the early 1970s. There is no island-wide documentation of forest clearance or logging since the 1970s. This creates an information gap for conservation planning, especially with regard to selectively logged forests that maintain high conservation potential. Analysing LANDSAT images, we estimate that 75.7% (558,060 km2) of Borneos area (737,188 km2) was forested around 1973. Based upon a forest cover map for 2010 derived using ALOS-PALSAR and visually reviewing LANDSAT images, we estimate that the 1973 forest area had declined by 168,493 km2 (30.2%) in 2010. The highest losses were recorded in Sabah and Kalimantan with 39.5% and 30.7% of their total forest area in 1973 becoming non-forest in 2010, and the lowest in Brunei and Sarawak (8.4%, and 23.1%). We estimate that the combined area planted in industrial oil palm and timber plantations in 2010 was 75,480 km2, representing 10% of Borneo. We mapped 271,819 km of primary logging roads that were created between 1973 and 2010. The greatest density of logging roads was found in Sarawak, at 0.89 km km−2, and the lowest density in Brunei, at 0.18 km km−2. Analyzing MODIS-based tree cover maps, we estimate that logging operated within 700 m of primary logging roads. Using this distance, we estimate that 266,257 km2 of 1973 forest cover has been logged. With 389,566 km2 (52.8%) of the island remaining forested, of which 209,649 km2 remains intact. There is still hope for biodiversity conservation in Borneo. Protecting logged forests from fire and conversion to plantations is an urgent priority for reducing rates of deforestation in Borneo.


Ecology and Society | 2013

An operational framework for defining and monitoring forest degradation.

Ian D. Thompson; Manuel R. Guariguata; Kimiko Okabe; Carlos Bahamondez; Robert Nasi; Victoria Heymell; César Sabogal

Forest degradation is broadly defined as a reduction in the capacity of a forest to produce ecosystem services such as carbon storage and wood products as a result of anthropogenic and environmental changes. The main causes of degradation include unsustainable logging, agriculture, invasive species, fire, fuelwood gathering, and livestock grazing. Forest degradation is widespread and has become an important consideration in global policy processes that deal with biodiversity, climate change, and forest management. There is, however, no generally recognized way to identify a degraded forest because perceptions of forest degradation vary depending on the cause, the particular goods or services of interest, and the temporal and spatial scales considered. Here, we suggest that there are types of forest degradation that produce a continuum of decline in provision of ecosystem services, from those in primary forests through various forms of managed forests to deforestation. Forest degradation must be measured against a desired baseline condition, and the types of degradation can be represented using five criteria that relate to the drivers of degradation, loss of ecosystem services and sustainable management, including: productivity, biodiversity, unusual disturbances, protective functions, and carbon storage. These criteria are not meant to be equivalent and some might be considered more important than others, depending on the local forest management objectives. We propose a minimum subset of seven indicators for the five criteria that should be assessed to determine forest degradation under a sustainable ecosystem management regime. The indicators can be remotely sensed (although improving calibration requires ground work) and aggregated from stand to management unit or landscape levels and ultimately to sub-national and national scales.


Philosophical Transactions of the Royal Society B | 2013

State and evolution of the African rainforests between 1990 and 2010.

Philippe Mayaux; Jean-François Pekel; Baudouin Desclée; François Donnay; Andrea Lupi; Frédéric Achard; Marco Clerici; Catherine Bodart; Andreas Brink; Robert Nasi; Alan Belward

This paper presents a map of Africas rainforests for 2005. Derived from moderate resolution imaging spectroradiometer data at a spatial resolution of 250 m and with an overall accuracy of 84%, this map provides new levels of spatial and thematic detail. The map is accompanied by measurements of deforestation between 1990, 2000 and 2010 for West Africa, Central Africa and Madagascar derived from a systematic sample of Landsat images—imagery from equivalent platforms is used to fill gaps in the Landsat record. Net deforestation is estimated at 0.28% yr−1 for the period 1990–2000 and 0.14% yr−1 for the period 2000–2010. West Africa and Madagascar exhibit a much higher deforestation rate than the Congo Basin, for example, three times higher for West Africa and nine times higher for Madagascar. Analysis of variance over the Congo Basin is then used to show that expanding agriculture and increasing fuelwood demands are key drivers of deforestation in the region, whereas well-controlled timber exploitation programmes have little or no direct influence on forest-cover reduction at present. Rural and urban population concentrations and fluxes are also identified as strong underlying causes of deforestation in this study.


The forests of the Congo basin: state of the forests 2006. | 2012

The Forests of the Congo Basin: State of the Forest 2010

C. de Wasseige; P. de Marcken; Nicolas Bayol; F Hiol-Hiol; Philippe Mayaux; Baudouin Desclée; Robert Nasi; Alain Billand; Pierre Defourny; R. Eba'a Atyi

Meat from wild terrestrial or semi-terrestrial animals, termed „bushmeat‟, is a significant source of animal protein in Central African countries, and a crucial component of food security and livelihoods in rural areas. Estimates of bushmeat consumption across the Congo Basin range between 1 million tonnes (Wilkie and Carpenter 1999) and 5 million tonnes (Fa et al. 2003) and harvest rates are estimated to range from 23 to 897 kg/km 2 /year (Nasi et al. 2008). Many sustainability assessments focusing on tropical forest wildlife in the region have warned about the increasing unsustainability of hunting and associated ecological impacts (e.g. examples within Bennett and Robinson, 2000).The term “value chain” is useful to understand the activities involved in bringing a product from the forest, through processing and production, to delivery to final consumers and ultimately disposal (Kaplinsky & morris, 2000). Value chain analysis is a conceptual framework for mapping and categorizing the economic, social and environmental processes. It helps to understand how and where enterprises and institutions are positioned in chains, and to identify opportunities and possible leverage points for upgrading. This analysis encompasses the organization, coordination, equity, power relationships, linkages and governance between organizations and actors. Photo 7.1: Kola nuts (Cola acuminata) for sale in a market in Kisangani, DRC


Ecology and Society | 2008

Sustainable Forest Management in Cameroon Needs More than Approved Forest Management Plans

Paolo Omar Cerutti; Robert Nasi; Luca Tacconi

One of the main objectives of the 1994 Cameroonian forestry law is to improve the management of production forests by including minimum safeguards for sustainability into compulsory forest management plans. As of 2007, about 3.5 million hectares (60%) of the productive forests are harvested following the prescriptions of 49 approved management plans. The development and implementation of these forest management plans has been interpreted by several international organizations as long awaited evidence that sustainable management is applied to production forests in Cameroon. Recent reviews of some plans have concluded, however, that their quality was inadequate. This paper aims at taking these few analyses further by assessing the actual impacts that approved management plans have had on sustainability and harvesting of commercial species. We carry out an assessment of the legal framework, highlighting a fundamental flaw, and a thorough comparison between data from approved management plans and timber production data. Contrary to the principles adhered to by the 1994 law, we find that the government has not yet succeeded in implementing effective minimum sustainability safeguards and that, in 2006, 68% of the timber production was still carried out as though no improved management rules were in place. The existence of a number of approved management plans cannot be used a proxy for proof of improved forest management.


Scientific Reports | 2015

Major atmospheric emissions from peat fires in Southeast Asia during non-drought years: evidence from the 2013 Sumatran fires

David Gaveau; Mohammad A. Salim; Kristell Hergoualc'h; Bruno Locatelli; Sean Sloan; Martin J. Wooster; Miriam E. Marlier; Elis Molidena; Husna Yaen; Ruth S. DeFries; Louis Verchot; Daniel Murdiyarso; Robert Nasi; Peter Holmgren; Douglas Sheil

Trans-boundary haze events in Southeast Asia are associated with large forest and peatland fires in Indonesia. These episodes of extreme air pollution usually occur during drought years induced by climate anomalies from the Pacific (El Niño Southern Oscillation) and Indian Oceans (Indian Ocean Dipole). However, in June 2013 – a non-drought year – Singapores 24-hr Pollutants Standards Index reached an all-time record 246 (rated “very unhealthy”). Here, we show using remote sensing, rainfall records and other data, that the Indonesian fires behind the 2013 haze followed a two-month dry spell in a wetter-than-average year. These fires were short-lived (one week) and limited to a localized area in Central Sumatra (1.6% of Indonesia): burning an estimated 163,336 ha, including 137,044 ha (84%) on peat. Most burning was confined to deforested lands (82%; 133,216 ha). The greenhouse gas (GHG) emissions during this brief, localized event were considerable: 172 ± 59 Tg CO2-eq (or 31 ± 12 Tg C), representing 5–10% of Indonesias mean annual GHG emissions for 2000–2005. Our observations show that extreme air pollution episodes in Southeast Asia are no longer restricted to drought years. We expect major haze events to be increasingly frequent because of ongoing deforestation of Indonesian peatlands.


Environmental Conservation | 2003

Towards sustainable management of mixed dipterocarp forests of South-east Asia: moving beyond minimum diameter cutting limits

Plinio Sist; Robert Fimbel; Douglas Sheil; Robert Nasi; Marie-Hélène Chevallier

SUMMARY Selective logging applied in tropical forests is based on one universal criterion: a minimum diameter cutting limit for all commercial timber species. Minimum diameter cutting limits in mixed dipterocarp forests of the Malesia region lead to high felling intensities (10‐20� trees ha � 1 ). Such extraction rates create massive stand damage (� 50% of the remaining tree population), which has a negative impact on the regeneration and growth of many harvested dipterocarp species. As such, the minimum diameter cutting limit approach is seldom compatible with sustainable forest management. Where basic ecological characteristics of the commercial species are considered in timber harvesting prescriptions, mixed dipterocarp forests appear capable of sustained timber yields, habitat conservation, and providing other goods and services. This paper first presents the main silvicultural systems developed in mixed dipterocarp forests of Western Malesia and then reviews current knowledge of dipterocarp biology to finally develop guidelines aimed at improving the ecological sustainability of production forests of Western Malesia. These guidelines, a pragmatic reflection of science and ‘best guess’ judgement, include: (1) integration of reduced-impact logging practices into normal management operations; (2) cutting of eight trees ha � 1 or less (with a felling cycle of 40‐60 years to be determined according to local conditions); (3) defining minimum diameter cutting limits according to the structure, density and diameter at reproduction of target species; (4) avoiding harvesting species with less than one adult tree ha � 1 (diameter at breast height [dbh] � 50 cm over an area of 50‐100 ha); (5) minimizing the size and connectivity of gaps (� 600 m 2 whenever possible); (6) refraining from treatments such as understorey clearing; and (7) providing explicit protection for key forest species and the ecological processes they perform. Further refinement is encouraged to allow for local conditions, and for other forest types.


Conservation Biology | 2010

Biodiversity conservation in agricultural landscapes: challenges and opportunities of coffee agroforests in the Western Ghats, India

Claude A. Garcia; Shonil A. Bhagwat; Jaboury Ghazoul; Cheryl D. Nath; Konerira M. Nanaya; Cheppudira G. Kushalappa; Robert Nasi; Philippe Vaast

The new approaches advocated by the conservation community to integrate conservation and livelihood development now explicitly address landscape mosaics composed of agricultural and forested land rather than only protected areas and largely intact forests. We refer specifically to a call by Harvey et al. (2008) to develop a new approach based on six strategies to integrate biodiversity conservation with sustainable livelihoods in Mesoamerican landscape mosaics. We examined the applicability of this proposal to the coffee agroforests of the Western Ghats, India. Of the six strategies, only one directly addresses livelihood conditions. Their approach has a clear emphasis on conservation and, as currently formulated risks repeating the failures of past integrated conservation and development projects. It fails to place the aspirations of farmers at the core of the agenda. Thus, although we acknowledge and share the broad vision and many of the ideas proposed by this approach, we urge more balanced priority setting by emphasizing people as much as biodiversity through a careful consideration of local livelihood needs and aspirations.


BioScience | 2011

Forest Biodiversity and the Delivery of Ecosystem Goods and Services: Translating Science into Policy

Ian D. Thompson; Kimiko Okabe; Jason M. Tylianakis; Pushpam Kumar; Eckehard G. Brockerhoff; Nancy A. Schellhorn; John A. Parrotta; Robert Nasi

Biodiversity is integral to almost all ecosystem processes, with some species playing key functional roles that are essential for maintaining the value of ecosystems to humans. However, many ecosystem services remain nonvalued, and decisionmakers rarely consider biodiversity in policy development, in part because the relationships between biodiversity and the provision of ecosystem services are not generally appreciated. To date, the majority of work in which the functional importance of biodiversity has been examined has been conducted in relatively species-poor systems. Focusing on forest and agroforest systems, we synthesize recent research on the role of biodiversity in the provision of ecosystem services and provide examples of biodiversity science that informs ecosystem management and policy. Finally, we highlight barriers to the transfer of knowledge from scientists to decisionmakers and suggest that scientists can be much more effective at informing policy and improving resource management by asking policy-relevant questions and providing timely and consistent information to decisionmakers and the public on the linkages among biodiversity, ecosystem services, and their value to people.

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N. Van Vliet

Center for International Forestry Research

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Paolo Omar Cerutti

Center for International Forestry Research

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John E. Fa

Manchester Metropolitan University

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Alain Billand

Centre de coopération internationale en recherche agronomique pour le développement

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Douglas Sheil

Center for International Forestry Research

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Sylvie Gourlet-Fleury

Centre de coopération internationale en recherche agronomique pour le développement

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Manuel R. Guariguata

Center for International Forestry Research

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Guillaume Lescuyer

Centre de coopération internationale en recherche agronomique pour le développement

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Plinio Sist

Empresa Brasileira de Pesquisa Agropecuária

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