Inequitable Gains and Losses from Conservation in a Global Biodiversity Hotspot

A billion rural people live near tropical forests. Urban populations need them for water, energy and timber. Global society benefits from climate regulation and knowledge embodied in tropical biodiversity. Ecosystem service valuations can incentivise conservation, but determining costs and benefits across multiple stakeholders and interacting services is complex and rarely attempted. We report on a 10-year study, unprecedented in detail and scope, to determine the monetary value implications of conserving forests and woodlands in Tanzania’s Eastern Arc Mountains. Across plausible ranges of carbon price, agricultural yield and discount rate, conservation delivers net global benefits (+US$8.2B present value, 20-year central estimate). Crucially, however, net outcomes diverge widely across stakeholder groups. International stakeholders gain most from conservation (+US$10.1B), while local-rural communities bear substantial net costs (-US$1.9B), with greater inequities for more biologically important forests. Other Tanzanian stakeholders experience conflicting incentives: tourism, drinking water and climate regulation encourage conservation (+US$72M); logging, fuelwood and management costs encourage depletion (-US$148M). Substantial global investment in disaggregating and mitigating local costs (e.g., through boosting smallholder yields) is essential to equitably balance conservation and development objectives

Inequitable gains and losses from conservation in a global biodiversity hotspot

A billion rural people live near tropical forests. Urban populations need them for water, energy and timber. Global society benefits from climate regulation and knowledge embodied in tropical biodiversity. Ecosystem service valuations can incentivise conservation, but determining costs and benefits across multiple stakeholders and interacting services is complex and rarely attempted. We report on a 10-year study, unprecedented in detail and scope, to determine the monetary value implications of conserving forests and woodlands in Tanzania’s Eastern Arc Mountains. Across plausible ranges of carbon price, agricultural yield and discount rate, conservation delivers net global benefits (+US$8.2B present value, 20-year central estimate). Crucially, however, net outcomes diverge widely across stakeholder groups. International stakeholders gain most from conservation (+US$10.1B), while local-rural communities bear substantial net costs (-US$1.9B), with greater inequities for more biologically important forests. Other Tanzanian stakeholders experience conflicting incentives: tourism, drinking water and climate regulation encourage conservation (+US$72M); logging, fuelwood and management costs encourage depletion (-US$148M). Substantial global investment in disaggregating and mitigating local costs (e.g., through boosting smallholder yields) is essential to equitably balance conservation and development objectives

Biomass and volume models for different vegetation types of Tanzania

Climate change and high rates of global carbon dioxide (CO2) emissions have increased the attention paid to the need for high-quality monitoring systems to assess how much carbon (C) is present in terrestrial systems and how these change over time. The choice of a system to adopt relies heavily on the accuracy of the method for quantifying biomass and volume as important primary variables for computing C stock and changes over time. Methods based on ground forest inventory and remote sensing data have commonly been applied in the recent decade to estimate biomass and volume in the tropical forests. However, regardless of the method, accurate tree level biomass and volume models are needed to translate field or remotely sensed data into estimates of forest biomass and volume. Therefore, the main goal of this study was to develop biomass and volume models for the forests, woodlands, thickets, agroforestry systems and some selected tree species in Tanzania. Data from destructively sampled trees were used to develop volume and above- and below-ground biomass models. Different statistical criteria, including coefficient of determination (R2), relative root mean square error (RMSE %) and Akaike Information Criterion (AIC), were used to assess the quality of the model fits. The models selected showed good prediction accuracy and, therefore, are recommended not only to support the ongoing initiatives on forest C Measurement, Reporting and Verificatio (MRV) processes but also for general forest management in Tanzania

Mixed method approaches to evaluate conservation impact: evidence from decentralized forest management in Tanzania

Nearly 10% of the world’s total forest area is formally owned by communities and indigenous groups, yet knowledge of the effects of decentralized forest management approaches on conservation (and livelihood) impacts remains elusive. In this paper, the conservation impact of decentralized forest management on two forests in Tanzania was evaluated using a mixed method approach. Current forest condition, forest increment and forest use patterns were assessed through forest inventories, and changes in forest disturbance levels before and after the implementation of decentralized forest management were assessed on the basis of analyses of Landsat images. This biophysical evidence was then linked to changes in actual management practices, assessed through records, interviews and participatory observations, to provide a measure of the conservation impact of the policy change. Both forests in the study were found to be in good condition, and extraction was lower than overall forest increment. Divergent changes in forest disturbance levels were in evidence following the implementation of decentralized forest management. The evidence from records, interviews and participatory observations indicated that decent- ralized management had led to increased control of forest use and the observed divergence in forest disturbance levels appeared to be linked to differences in the way that village-level forest managers prioritized conservation objectives and forest-based livelihood strategies. The study illustrates that a mixed methods approach comprises a valid and promising way to evaluate impacts of conservation policies, even in the absence of control sites. By carefully linking policy outcomes to policy outputs, such an approach not only identifies whether such policies work as intended, but also potential mechanisms

Biomass and volume models for different vegetation types of Tanzania

Climate change and high rates of global carbon dioxide (CO2) emissions have increased the attention paid to the need for high-quality monitoring systems to assess how much carbon (C) is present in terrestrial systems and how these change over time. The choice of a system to adopt relies heavily on the accuracy of the method for quantifying biomass and volume as important primary variables for computing C stock and changes over time. Methods based on ground forest inventory and remote sensing data have commonly been applied in the recent decade to estimate biomass and volume in the tropical forests. However, regardless of the method, accurate tree level biomass and volume models are needed to translate field or remotely sensed data into estimates of forest biomass and volume. Therefore, the main goal of this study was to develop biomass and volume models for the forests, woodlands, thickets, agroforestry systems and some selected tree species in Tanzania. Data from destructively sampled trees were used to develop volume and above- and below-ground biomass models. Different statistical criteria, including coefficient of determination (R2), relative root mean square error (RMSE %) and Akaike Information Criterion (AIC), were used to assess the quality of the model fits. The models selected showed good prediction accuracy and, therefore, are recommended not only to support the ongoing initiatives on forest C Measurement, Reporting and Verificatio (MRV) processes but also for general forest management in Tanzania

Mixed method approaches to evaluate conservation impact:evidence from decentralized forest management in Tanzania

This article is available at http://www.doi.org/10.1017/S0376892914000241Nearly 10% of the world’s total forest area is formally owned by communities and indigenous groups, yet knowledge of the effects of decentralized forest management approaches on conservation (and livelihood) impacts remains elusive. In this paper, the conservation impact of decentralized forest management on two forests in Tanzania was evaluated using a mixed method approach. Current forest condition, forest increment and forest use patterns were assessed through forest inventories, and changes in forest disturbance levels before and after the implementation of decentralized forest management were assessed on the basis of analyses of Landsat images. This biophysical evidence was then linked to changes in actual management practices, assessed through records, interviews and participatory observations, to provide ameasure of the conservation impact of the policy change. Both forests in the study were found to be in good condition, and extraction was lower than overall forest increment. Divergent changes in forest disturbance levels were in evidence following the implementation of decentralized forest management. The evidence from records, interviews and participatory observations indicated that decentralized management had led to increased control of forest use and the observed divergence in forest disturbance levels appeared to be linked to differences in theway that village-level forest managers prioritized conservation objectives and forest-based livelihood strategies. The study illustrates that a mixed methods approach comprises a valid and promising way to evaluate impacts of conservation policies, even in the absence of control sites. By carefully linking policy outcomes to policy outputs, such an approach not onlyidentifies whether such policies work as intended, but also potential mechanisms

Mixed method approaches to evaluate conservation impact: evidence from decentralized forest management in Tanzania

Nearly 10% of the world’s total forest area is formally owned by communities and indigenous groups, yet knowledge of the effects of decentralized forest management approaches on conservation (and livelihood) impacts remains elusive. In this paper, the conservation impact of decentralized forest management on two forests in Tanzania was evaluated using a mixed method approach. Current forest condition, forest increment and forest use patterns were assessed through forest inventories, and changes in forest disturbance levels before and after the implementation of decentralized forest management were assessed on the basis of analyses of Landsat images. This biophysical evidence was then linked to changes in actual management practices, assessed through records, interviews and participatory observations, to provide a measure of the conservation impact of the policy change. Both forests in the study were found to be in good condition, and extraction was lower than overall forest increment. Divergent changes in forest disturbance levels were in evidence following the implementation of decentralized forest management. The evidence from records, interviews and participatory observations indicated that decent- ralized management had led to increased control of forest use and the observed divergence in forest disturbance levels appeared to be linked to differences in the way that village-level forest managers prioritized conservation objectives and forest-based livelihood strategies. The study illustrates that a mixed methods approach comprises a valid and promising way to evaluate impacts of conservation policies, even in the absence of control sites. By carefully linking policy outcomes to policy outputs, such an approach not only identifies whether such policies work as intended, but also potential mechanisms