Forests In Tanzania Research Articles

Microbial carbon oxidation rates and pathways in sediments of two Tanzanian mangrove forests

Temporal and spatial variations in benthic metabolism and anaerobic carbon oxidation pathways were assessed in an anthropogenically impacted (Mtoni) and a pristine (Ras Dege) mangrove forest in Tanzania. The objectives were (1) to evaluate how benthic metabolism is affected by organic carbon availability; (2) to determine the validity of diffusive release of CO2 as a measure benthic carbon oxidation; and (3) to assess the partitioning of anaerobic carbon pathways and factors controlling the availability of electron acceptors (e.g. oxidized iron). Microbial carbon oxidation measured as diffusive exchange of O2 and CO2 (32–67 and 28–115 mmol m−2 day−1, respectively) showed no specific temporal patterns. Low intertidal sediments at Mtoni fed by labile algal carbon of anthropogenic origin had higher diffusive CO2 release than high intertidal sediments that primarily received less reactive mangrove detritus. Diffusive release of CO2 apparently underestimated total sediment carbon oxidation due to CO2 loss from deep sediments via emission through biogenic structures (i.e. crab burrows and pneumatophores) and porewater seepage into creeks. We propose that diffusive fluxes in the present mangrove sediments are roughly equivalent to depth-integrated reactions occurring in the upper 12 cm. Anaerobic carbon oxidation was dominated by FeR irrespective of anthropogenic influence in sediments where the oxidizing effects of biogenic structures increased the Fe(III) level. More than 80% of the anaerobic carbon oxidation in Mtoni and Ras Dege sediments was due to FeR when reactive Fe(III) exceeded 30 μmol cm−3. The anthropogenic influence at Mtoni was primarily noted as up to one order of magnitude higher denitrification than at Ras Dege, but this process always accounted for less than 1% of total carbon oxidation. It is noteworthy that organic and nutrient enrichment of anthropogenic origin in Mtoni has no measurable effect on microbial processes, other than carbon oxidation in the low intertidal area and denitrification throughout the forest, and indicates a strong resilience of mangrove environments towards disturbances.

Management Decentralization and Montane Forest Conditions in Tanzania

We examined how differences in local forest-management institutions relate to disparate anthropogenic forest disturbance and forest conditions among three neighboring montane forests in Tanzania under centralized, comanaged, or communal management. Institutional differences have been shaped by decentralization reforms. We conducted semistructured interviews with members of forest management committees, local government, and village households and measured anthropogenic disturbance, tree structure, and species composition in forest plots. We assessed differences in governance system components of local institutions, including land tenure, decision-making autonomy by forest users, and official and de facto processes of rule formation, monitoring, and enforcement among the three management strategies. We also assessed differences in frequencies of prohibited logging and subsistence pole cutting, and measures of forest condition. An adjacent research forest served as an ecological reference for comparison of forest conditions. Governance was similar for comanaged and centralized management, whereas communal managers had greater tenure security and decision-making autonomy over the use and management of their forest. There was significantly less illegal logging in the communal forest, but subsistence pole cutting was common across all management strategies. The comanaged forest was most disturbed by recent logging and pole cutting, as were peripheral areas of the larger centralized forest. This manifested in more degraded indicators of forest conditions (lower mean tree size, basal area, density of trees >or= 90 cm dbh, and aboveground biomass and higher overall stem density). Greater tenure security and institutional autonomy of the communal strategy contributed to more effective management, less illegal logging, and maintenance of good forest conditions, but generating livelihood benefits was a challenge for both decentralized strategies. Our results underscore the importance of well-designed institutional arrangements in forest management and illustrate mechanisms for improved forest governance and conservation in the context of Tanzanian decentralization reforms.

Mitochondrial evidence for the hybrid origin of the kipunji, Rungwecebus kipunji (Primates: Papionini)

Common baboons ( Papio), gelada baboons ( Theropithecus) and baboon–mangabeys ( Lophocebus) are closely related African papionin monkeys. In 2005, the species Lophocebus kipunji was described from relict montane and submontane forests in Tanzania, based upon a single specimen and observations of living animals. Its initial assignment to Lophocebus was based on its overall morphology, but subsequent genetic studies suggesting that it was sister taxon to common baboons ( Papio) led to its generic separation, as Rungwecebus. As a mangabey-like sister-taxon to Papio, Rungwecebus could be interpreted either as an arboreal derivative from a more terrestrial, baboon-like ancestor, or as a survivor of a mangabey-like common ancestor of the Lophocebus–Papio–Theropithecus clade. Here, we present a new, strongly-supported, mitochondrial DNA (mtDNA) phylogeny that includes Papio baboons from populations geographically close to the kipunji. Rather than supporting sister-taxon status, the new phylogeny not only situates the kipunji’s mtDNA among Papio haplotypes, it clearly assigns it to a mitochondrial clade including geographically adjacent yellow baboons ( Papio cynocephalus). This relationship suggests either that the kipunji is descended from a yellow baboon, and has converged on a mangabey-like morphology, or, much more likely, that it originated by hybridization between Papio cf . cynocephalus females and Lophocebus sp. males, about 0.65 Ma. We believe this to be the first case among mammals in which a natural occurrence of inter-generic hybridization can be shown to have resulted in a new, distinct, long-surviving taxon. More such cases can be anticipated as molecular evidence accumulates.

Species richness and abundance estimates of small mammals in Zaraninge coastal forest in Tanzania

Species richness and abundance estimates of small mammals in Zaraninge coastal forest in Tanzania

Has the woodfuel crisis returned? Urban charcoal consumption in Tanzania and its implications to present and future forest availability

By lumping together charcoal and firewood consumption to determine the threats to forests from widespread use of woodfuel energy in sub-Sahara African, studies have greatly underestimated the individual impact of charcoal. Where high consumption levels are coupled with poor forest management and negligible regulation of the charcoal trade, the threat of an impending crisis caused by charcoal alone needs to be revisited. This study uses a survey of 244 households in six Tanzanian cities to determine whether current consumption levels, charcoal production techniques and forest management practices are sufficient to meet present and future charcoal demand. Projections to year 2100 were made to determine whether forests can continue to meet future demand under 24 scenarios that capture the numerous uncertainties that exist of converting charcoal consumption into forest needed. The findings suggest that the scenarios containing median consumption levels, low kiln efficiencies and low replenishment of harvested forests could deplete forests on public land by 2028. Best-case scenarios occurred when the opposite conditions existed. The study concludes that charcoal consumption is a real threat to the long-term persistence of forests in Tanzania and proposes policy interventions for alleviating forest loss.

Comparative penile morphology of East African galagos of the genus Galagoides (family Galagidae): implications for taxonomy

Recent studies on the comparative penile morphology of galagos have revealed complex patterns that vary among both genera and species, and help with species identification. So far the penile morphologies of 14 galago species have been described and an identification key has been proposed. The present study extends and revises previous work. Wild Galagoides cocos, G. granti, G. zanzibaricus and G. rondoensis from the Eastern Arc Mountains and coastal forests of Tanzania and Kenya were live-trapped, and one species (G. orinus) was examined using a museum specimen. Penile morphology was photographed, traced, and described qualitatively. All of the mature males had penile spines. Spines were absent or indistinct in immature males of all of the species. The penile morphologies of G. cocos, G. granti, and G. zanzibaricus are similar in their overall distribution and type of spines, but differ in the shape of the glans penis. Both G. orinus and G. rondoensis have divergent penile morphologies compared to all other galagos, and are probably phylogenetically distinct. The results support other recent morphological and behavioral studies that consider these five galagos to be distinct species. The evolution of the baculum and spines is thought to be linked to sexual selection in multimale mating systems, but the mechanisms involved are not entirely understood. Adult male G. rondoensis appear to display the penile spines by exposing the distal section of the penis.

Amphibian Diversity in East African Biodiversity Hotspots: Altitudinal and latitudinal Patterns

The Eastern Arc mountain chain and adjoining coastal forests of Tanzania and Kenya have been listed as world biodiversity hotspots. We report on an ongoing attempt to estimate amphibian diversity on the three best studied mountains of the Eastern Arc, the East Usambara, Uluguru and Udzungwa mountains of Tanzania, complemented by an estimate of diversity on the adjoining coastal lowland. This proves to be a complex task, which introduces a note of caution into evaluating global biodiversity estimates. Most amphibian species in eastern Tanzania occur on the coastal lowlands and are widely distributed, extending at least north or south of Tanzania and, to a variable extent, westwards to the elevated interior. Diversity patterns along the length of the lowlands are complex, with the presence of a Sahelian element in the extreme north. On the three Eastern Arc mountains studied, species turnover associated with rising altitude is greater than turnover associated with latitudinal distance between the mountain blocks, leading to greater altitudinal than latitudinal diversity in this equatorial region. A long-standing divergence is indicated between montane and lowland endemics. Although forest-associated species are not the largest contributor to the eastern Tanzanian total species diversity (some 48%), the uniqueness of these species both in lowland and montane forests, combined with their evident vulnerability to disturbance, makes them a subject for particular conservation concern, and justifies hotspot status for both montane and lowland forests.

Monitoring the health of selected eastern arc forests in Tanzania

AbstractThe eastern arc mountains (EAMs) are a chain of isolated mountains (534,000 ha) in Kenya and Tanzania surrounded by arid woodlands and influenced by the Indian Ocean. In 1900 there was three times the amount of forest cover there is today. Much of the original forests have been converted into agricultural crops. These mountains are recognized as a globally important ‘hot spot’ by World Wide Fund for Nature (WWF) and World Conservation of Union (IUCN) for forest biodiversity and are major national, regional and local sources of hydropower, water and wide array of forest‐based benefits and agricultural production. In February 2000 we began a 3‐year evaluation of forest health, land‐use change and information sharing in the EAMs. Permanent sample plots were used to evaluate forest health. This paper summarizes the baseline data from eighteen permanent sample plots in the east Usambara's and nine in Ulugurus. The eastern arc web site (http://www.easternarc.org) was established, continues to expand and contains some detailed information on the project. Information gathered will assist land managers, planners, policy makers, interested communities (villages) and individuals in decision‐making. These data can also provide an early warning system of stresses on forest catchments.

The discovery of a second species of Cryptophilharmostes Balleriofrom Tanzania (Coleoptera: Scarabaeoidea: Ceratocanthidae)

Cryptophilharmostes merkli n. sp. is described from the Uluguru Mountains in eastern Tanzania. This is the second known species of this genus, which is only known for the Eastern Arc/Coastal lowland forests of Tanzania. The generic level characters of Cryptophilharmostes are revised and observations of the sexual dimorphism and male genitalia of this genus are included.

Highland sanctuary: environmental history in Tanzania's Usambara Mountains

For More Than A Century, The World has recognized the extraordinary biological diversity of the forests of Tanzania's Usambara Mountains. As international attention has focused on forest conservation, farmers, foresters, biologists, and the Tanzanian state have realized that only complex negotiations will save these treasured, but rapidly disappearing, landscapes. Highland Sanctuary unravels the complex interactions among agriculture, herding, forestry, the colonial state, and the landscape itself. In his examination of the region's history of ecological transformation, Christopher Conte demonstrates how these forces have combined to create an ever-changing mosaic of forest and field. His study illuminates the debate over conservation, arguing that contingency and chance, the stuff of human history, have shaped forests in ways that rival the power of nature. In Highland Sanctuary, the forest becomes part of human history, rather than something outside of it. Highland Sanctuary cuts through a legacy of contention and ill will to inform contemporary conservation initiatives. Professor Conte explains how ecological changes take divergent paths in similar environments, in this case on mountains that harbor unique flora and fauna, and how these mountain environments achieve international importance as centers of biodiversity.

Carbon Sequestration in Rural Communities

SUMMARY This study focuses on the possibility for income generation through carbon sequestration in land-use related projects under the Clean Development Mechanism (CDM) of the Kyoto protocol. The carbon sequestration potential of agroforestry and forestry projects was studied in Nepal, Uganda and Tanzania. Carbon sequestration in biomass was 0.43 and 2.0 Mg C ha−1 year−1 in regeneration of natural forests in Tanzania and Nepal, respectively. Carbon sequestration rates in planted forests were 4.0 Mg C ha−1 year−1 for Eucalyptus woodlots in Uganda and 5.9 Mg C ha−1 year−1 for Pinus patula plantations in Tanzania. The economic profitability of these land-use systems was calculated using the Net Present Value (NPV). Based on a carbon price of US $10 per ton (Mg) and an annual interest rate of 10%, the NPV increased by between 4.9% and 6.5% for these systems when the carbon value was added to the timber value and value of non-wood products. This increase in value is probably too small to justify the cost in relation to project development, establishment of baseline, carbon monitoring costs, assessment of leakage and documentation of the effect on sustainable development.

Composition and diversity of the spider fauna in the canopy of a montane forest in Tanzania

Spiders were sampled using insecticide knockdown in an African montane forest in the Uzungwa Mountains of Tanzania. The results are used to discuss the faunal composition at the site and in comparison to other sites, and the implications of the results for estimating spider diversity in Africa are discussed. A total of 5233 adults comprising 149 species were collected from 11 samples covering a total of 906 m2 of projected area. Three species contributed 45% of the sample. Previous insecticide knockdown studies of tropical lowland forest canopies have shown a dominance of Theridiidae, Salticidae and Araneidae. In the present study Linyphiidae dominated in abundance and were the second most diverse in terms of species richness. Other abundant families were Oonopidae and Pholcidae, while Theridiidae, Salticidae and Araneidae were rich in species. This supports a previous study, which indicated that the importance of linyphiids increases with altitude. Species richness was predicted using a number of estimators, which produced relatively similar results. Using the abundance-based estimator, Chao 1, the predicted richness for the total area sampled is 183 ± 15 species. This indicates that at least 20% of the area's spider community remains unsampled. A high ratio of undescribed species (approximately 80%) and a relatively high species turnover compared to a site 20 km away within the same forest complex suggests that the number of spiders in Africa could well be much higher than the current, published estimate of 20000 species.

The role of traditional institutions in the conservation of forest resources in East Usambara, Tanzania

SUMMARY The study investigated the role of traditional institutions in the conservation of the East Usambara forests in Tanzania. It revealed that there had been institutional changes in management of forests, which had a negative impact on forest conservation. However, the presence of traditional institutions, which included among others traditional healers, traditional leaders, traditional taboos, sacred species and sites, had active roles in conserving the forest. More than 90% of the respondents had retained indigenous tree species on their farms and around households, with an average of six trees per household. This strategy is influenced by socio-economic factors whereby respondent age had a significant positive influence on the number of trees retained by a household. The study concludes by pointing out that traditional institutions have active roles in conserving the forests, and recommends that various strategies must be combined, including the use of traditional institutions, in Conservation of forests. Studying tradition institutions will give us knowledge on how they operate and how they can be combined with other strategies in government, NGOs and even the private sector in conservation of the forests. Socio-economic factors must be taken into account in the management of natural resources.

Potential and Cost of Carbon Sequestration in the Tanzanian Forest Sector

The forest sector in Tanzania offers ample opportunities to reduce greenhouse gas emissions (GHG) and sequester carbon (C) in terrestrial ecosystems. More than 90% of the country's demand for primary energy is obtained from biomass mostly procured unsustainably from natural forests. This study examines the potential to sequester C through expansion of forest plantations aimed at reducing the dependence on natural forest for wood fuel production, as well as increase the country's output of industrial wood from plantations. These were compared ton conservationoptions in the tropical and miombo ecosystems. Three sequestrationoptions were analyzed, involving the establishment of short rotation and long rotation plantations on about 1.7 × 106 hectares. The short rotation community forestry option has a potential to sequester an equilibrium amount of 197.4 × 106 Mg C by 2024 at a net benefit of 79.5 × 106, while yielding a NPV of 0.46 Mg-1 C. The long rotation options for softwood and hardwood plantations will reach an equilibrium sequestration of 5.6 and 11.8 × 106 Mg C at a negative NPV of 0.60 Mg-1 C and 0.32 Mg-1 C. The three options provide cost competitive opportunities for sequestering about 7.5 × 106 Mg C yr-1 while providing desired forest products and easing the pressure on the natural forests in Tanzania. The endowment costs of the sequestration options were all found to be cheaper than the emission avoidance cost for conservation options which had an average cost of 1.27 Mg-1 C, rising to 7.5 Mg-1 C under some assumptions on vulnerability to encroachment. The estimates shown here may represent the upper bound, because the actual potential will be influenced by market prices for inputs and forest products, land use policy constraints and the structure of global C transactions.

Forestry Mitigation Potential and Costs in Developing Countries Preface

The forest sector in Tanzania offers ample opportunities to reduce greenhouse gas emissions (GHG) and sequestered carbon (C) in terrestrial ecosystems. More than 90% of the country's demand for primary energy is obtained from biomass mostly procured unsustainably from natural forests. This study examines the potential to sequester C through expansion of forest plantations aimed at reducing the dependence on natural forest for wood fuel production, as well as increase the country's output of industrial wood from plantations. These were compared ton conservation options in the tropical and miombo ecosystems. Three sequestration options were analyzed, involving the establishment of short rotation and long rotation plantations on about 1.7 x 106 hectares. The short rotation community forest option has a potential to sequester an equilibrium amount of 197.4 x 106 Mg C by 2024 at a net benefit of $79.5 x 106, while yielding a NPV of $0.46 Mg-1 C. The long rotation options for softwood and hardwood plantations will reach an equilibrium sequestration of 5.6 and 11.8 x 106 Mg C at a negative NPV of $0.60 Mg-1 C and $0.32 Mg-1 C. The three options provide cost competitive opportunities for sequestering about 7.5 x 106 Mg C yr -1more » while providing desired forest products and easing the pressure on the natural forests in Tanzania. The endowment costs of the sequestration options were all found to be cheaper than the emission avoidance cost for conservation options which had an average cost of $1.27 Mg-1 C, rising to $7.5 Mg-1 C under some assumptions on vulnerability to encroachment. The estimates shown here may represent the upper bound, because the actual potential will be influenced by market prices for inputs and forest products, land use policy constraints and the structure of global C transactions.« less

Surface and leaf‐litter arthropods in the coastal forests of Tanzania

Surface and leaf litter arthropod assemblages of the seasonal lowland coastal forests of eastern Tanzania were investigated from eleven sites over a 3‐year period (1991–93). Pit‐fall trap data show that four groups comprise more than 10% of the total sample: ants (Hymenoptera: Formicidae, 31%), grasshoppers and crickets (Orthoptera, 22%), beetles (Coleoptera: 17.39%) and spiders (Araneae: 13.48%). Arthropod abundance varies considerably with season, with greater total numbers of arthropods in all groups found in wetter periods. Arthropod abundance also varies considerably according to habitat, with greatest numbers found in forests with the most intact canopy cover, and in valley‐bottom forest as compared to ridge‐top forest; the valleys are normally both wetter and with a more complete and taller canopy. Tullgren Funnel data show that over 50% of the leaf litter fauna comprises tiny arthropods of the groups Collembola and Acarina. Abundance of arthropods in the leaf litter of these forests varies from a maximum of ≈ 16,000 m–2, to a minimum of 780 m–2. Abundance is highest in wetter periods, in the forest areas with the most intact canopy cover, and in valley‐bottom as opposed to ridge‐top habitats.

New Species of Xylopia and Uvaria (Annonaceae) from Tanzania

Two new species of Annonaceae from the threatened lowland coastal forests of Tanzania are described and illustrated. Xylopia mwasumbii D. M. Johnson has distinctive flattened monocarps, unique among its African congeners. Uvaria puguensis D. M. Johnson is a small-flowered species belonging to a complex including, in East Africa, U. angolensis, U. lucida, and U. tanzaniae. A key to the taxa of the U. angolensis group in East Africa is provided. Annonaceae are especially diverse in the lowland coastal forests of Tanzania and Kenya, with six genera and 35 species endemic to these forests (Verdcourt, 1971, 1986; Verdcourt & Mwasumbi, 1988; Vollesen, 1980). At the same time that the biological diversity of these coastal forests is being recognized, this rare forest formation is disappearing due to pressure from land development and charcoal production (Burgess et al., 1992; Mwasumbi et al., 1994). Pugu Forest Reserve near Dar es Salaam, Tanzania, is the best-studied coastal forest in Tanzania (Burgess et al., 1992), yet we have just recently gathered sufficient material to describe two new species of Annonaceae, one in Xylopia and one in Uvaria, from this small reserve and nearby areas. Both species occur in forested uplands with a distinctive suite of associated species, including Baphia puguensis Brummitt, Hugonia castaneifolia Engler, Hymenaea verrucosa Gaertner, Hymenocardia ulmoides Oliver, Landolphia kirkii Dyer, Lasiodiscus holtzii Engler, Manilkara sulcata (Engler) Dubard, Monanthotaxis fornicata (Baillon) Verdcourt, Nesogordonia holtzii (Engler) Capuron, Scorodophloeus fischeri (Taubert) J. Leon, Suregada zanzibariensis Baillon, and Uvaria pandensis Verdcourt, as well as species of Croton, Haplocoelopsis, Ochna, Megalochlamys, Rinorea, and Tessmannia. Verdcourt (1971), in his treatment of Xylopia for the Flora of Tropical East Africa, first drew attention to the specimen Semsei 3704 from the Pugu Forest Reserve, identifying it as Xylopia Species B and commenting, material is scarcely adequate for description and only one of the two specimens seen bears flowers; both bear globose artichoke-like galls covered with conical tubercles which appear to be derived from the flowers. The name Xylopia Species B has, in the meantime, crept into East African floristic literature (e.g., Hawthorne, 1993), but it is now possible to name and describe this species in detail. Xylopia mwasumbii D. M. Johnson, sp. nov. TYPE: Tanzania. Coast Region: Kisarawe District, Pugu Forest Reserve, along N road 0.5 km E of brick factory, 6?52'S, 39006'E, 200 m, 16 Feb. 1996, Johnson & Ndangalasi 1884 (holotype, OWU; isotypes, DSM, K, MO). Figure 1A-H. Inter africanas Xylopiae species petalis lanceolatis olivaceis, staminibus non-capitatis, staminodiis nullis, carpellis duobus vel tribus, stigmatibus glabris oblongo-falcatis, toro leviter tantum concavo, et monocarpiis foliiformibus falcatis venosis compressis distincta. Tree 4-9 m tall, DBH up to 8 cm, often with multiple trunks, the principal trunk often arching rather than erect; bark white with gray and orange mottling, exfoliating in places; slash brown on yellow (ex Hawthorne). Nodes occasionally with two or more axillary branches. Twigs 0.7-2.1 mm diam., gray, longitudinally wrinkled, with epidermis soon exfoliating, sparsely lenticellate, sparsely appressed-pubescent to glabrate, the simple hairs 0.2-0.4 mm long. Lamina of larger leaves 4.6-7.7 cm long, 2.4--4.3 cm wide, paler abaxially, subcoriaceous, broadly elliptic to elliptic, occasionally ovate, elliptic-ovate, or obovate-elliptic; base cuneate, decurrent on petiole; apex 4-8 mm long, blunt-acuminate, or occasionally obtuse and emarginate; lamina with adaxial surface glabrous, abaxial surface sparsely sericeous; midrib impressed to plane adaxially, abaxially raised and keeled; secondary veins 9-11 per side, departing at 50-600 from the midrib, weakly brochidodromous, anastomosing 1-2 mm from margin; secondary and highNovoN 9: 55-60. 1999. This content downloaded from 157.55.39.138 on Tue, 19 Apr 2016 04:43:31 UTC All use subject to http://about.jstor.org/terms

Changing Roles in Natural Forest Management: A Case Study From the Udzungwa Mountains

The new Tanzanian forest policy was cleared in early 1998, and empowers community groups to own and manage forest resources. The Tanzania Forest Conservation Group (TFCG), a local NGO, is now in a position to rethink its role and move towards facilitating the balancing of local peoples' rights, responsibilities, returns from forest resources and relationship to forest maintenance. This article tracks changes in Lulanda Forest, in the Udzungwa, Eastern Arc Mountains, and analyses the evolution of local control over forest management.

96/03142 - Carbon flows and economic evaluation of mitigation options in Tanzania's forest sector

96/03142 - Carbon flows and economic evaluation of mitigation options in Tanzania's forest sector

Carbon flows and economic evaluation of mitigation options in Tanzania's forest sector

This paper presents estimates of the rate of forest use, deforestation and forest degradation, as well as the corresponding carbon flows, in the Tanzanian forest sector. It is estimated that the country lost 525,000 ha of forests in 1990, with associated committed emissions of 31.5 Mt carbon (MtC), and 7.05 MtC of committed carbon sequestration. The paper then describes the possible response options in the forest sector to mitigate GHG emissions, and evaluates the most stable subset of these—i.e. forest conservation, woodfuel plantations and agroforestry. The conservation options were found to cost an average of U.S.$1.27 per tonne of carbon (tC) conserved. Five options for fuelwood plantations and agroforestry, with two different ownership regimes were evaluated. Each one of the options gives a positive net present value at low rates of discount, ranging from U.S.$1.06 to 3.4/tC of avoided emissions at 0% discount rate. At 10% discount, the eucalyptus and maize option has a highest PNV of U.S.$1.73/tC, and the government plantation gives a negative PNV (loss) of U.S.$0.13 tC sequestered. The options with a private/community type of ownership scheme fared better than government run options. This conclusion also held true when ranking the options by the BRAC indicator, with the government fuelwood plantation ranked the lowest, and the private agroforestry option of eucalyptus and corn performing best. The mitigation options evaluated here show that the forest sector in Tanzania has one of the most cost-effective GHG mitigation opportunities in the world, and they are within the developmental aspirations of the country.