Browsing by Author "Malimbwi, Rogers"

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Carbon stocks for different land cover types in Mainland Tanzania
(2019-04) Malimbwi, Rogers; Zahabu, Eliakimu; Njana, Marco Andrew; Mugasha, Wilson Ancelm; Mauya, Ernest William
Background: Developing countries participating in the mitigation mechanism of reducing emissions from defor- estation and forest degradation (REDD+), are required to establish a forest reference emission level (FREL), if they wish to seek financial support to reduce carbon emissions from deforestation and forest degradation. However, establish- ment of FREL relies heavily on the accurate estimates of carbon stock as one of the input variable for computation of the emission factors (EFs). The product of an EF and activity data, such as the area of deforestation, results in the total emissions needed for establishment of FREL. This study presents the carbon stock estimates for different land cover classes based on an analysis of Tanzania’s national forest inventory data generated through the National Forest Resources Monitoring and Assessment (NAFORMA). Results: Carbon stocks were estimated in three carbon pools, namely aboveground, belowground, and deadwood for each of the three land cover classes (i.e. Forest, non-forest, and wetland). The weighted average carbon stock was 33.35 t C ha −1 for forest land, 4.28 t ha −1 for wetland and 5.81 t ha −1 for non-forest land. The uncertainty values were 0.9% for forest land, 11.3% for wetland and 1.8% for non-forest land. Average carbon stocks for land cover sub-classes, which make up the above mentioned major land cover classes, are also presented in our study. Conclusions: The values presented in this paper correspond to IPCC tier 3 and can be used for carbon estimation at the national scale for the respective major primary vegetation type for various purposes including REDD+. However, if local based estimates values are needed, the use of auxiliary data to enhance the precision of the area of interest is recommended. Keywords: Carbon stock, REDD+, FREL, Emission factor, Uncertainty
Forestland tenure systems in Tanzania: an overview of policy changes in relation to forest management
(Department of Ecology and Natural Resource Management Norwegian University of Life Sciences, 2009) Zahabu, Eliakimu; Eid, Tron; Kajembe, George; Mbwambo, L.; Mongo, Cellina; Sangeda, Anthony; Malimbwi, Rogers; Katan, Josiah; Kashaigili, Japhet; Luoga, Emmanuel
ummary Zahabu, E., Eid, T., Kajembe, G. C., Mbwambo, L., Mongo, C., Sangeda, A.Z., Malimbwi, R. E., Katani, J.Z., Kashaigili, J.J. and Luoga, E.J. 2009. Forestland tenure systems in Tanzania: an overview of policy changes in relation to forest management [Eiendomsforholdene for skogarealer i Tanzania: en oversikt over policyendringer i skogforvaltningen]. INA-fagrapport no. 14, 24 pp. A review of the role of forestland tenure systems in Tanzania, and how different forestland tenure approaches and reforms have influenced forest management is presented. The complexity of land reforms and processes that have taken place in Tanzania during the pre-colonial, colonial and post-independence periods is discussed. The pre-colonial period, though not much is written, was characterised by forest management through traditional institutions, low population and low forest resources exploitation. Colonial governments undermined the role of local traditions in managing the forests related to for example burial areas and springs. They also established forest reserves and in some areas cleared indigenous forests to establish tea, coffee and exotic fruit and timber plantations. Different land reforms that were geared towards sustainable development occurred after independence, forests depletion continued, however. Currently, it is observed that there coexists state, village, private and collective rights on forests without clear ownership. This is greatly linked to the ongoing deforestation and forest degradation in the country. In this situation, sustainable forestland use may be attained through establishing an enabling environment that allows effective local communities’ participation in forest management. Sustainable management, however, always presupposes effective control of harvesting and other activities to secure the carrying capacity of forests and woodlands, whether it is undertaken by central authorities or local people. Studies on forestland tenures and rights, and the impact of changes in tenures and rights on forest resources and rural livelihoods are therefore important. Such studies are required for the provision of facts for the establishment of proper future policy means that aim at reducing forest degradation and improving livelihoods in Tanzania.
Forestland tenure systems in Tanzania: an overview of policy changes in relation to forest management
(INA fagrapport, 2009) Zahabu, Eliakimu; Eid, Tron; Kajembe, George; Mbwambo, Lawrence; Mongo, Cellina; Sangeda, Anthony; Malimbwi, Rogers; Katani, Josiah; Kashaigili, Japhet; Luoga, Emmanuel
A review of the role of forestland tenure systems in Tanzania, and how different forestland tenure approaches and reforms have influenced forest management is presented. The complexity of land reforms and processes that have taken place in Tanzania during the pre-colonial, colonial and post-independence periods is discussed. The pre-colonial period, though not much is written, was characterised by forest management through traditional institutions, low population and low forest resources exploitation. Colonial governments undermined the role of local traditions in managing the forests related to for example burial areas and springs. They also established forest reserves and in some areas cleared indigenous forests to establish tea, coffee and exotic fruit and timber plantations. Different land reforms that were geared towards sustainable development occurred after independence, forests depletion continued, however. Currently, it is observed that there coexists state, village, private and collective rights on forests without clear ownership. This is greatly linked to the ongoing deforestation and forest degradation in the country. In this situation, sustainable forestland use may be attained through establishing an enabling environment that allows effective local communities’ participation in forest management. Sustainable management, however, always presupposes effective control of harvesting and other activities to secure the carrying capacity of forests and woodlands, whether it is undertaken by central authorities or local people. Studies on forestland tenures and rights, and the impact of changes in tenures and rights on forest resources and rural livelihoods are therefore important. Such studies are required for the provision of facts for the establishment of proper future policy means that aim at reducing forest degradation and improving livelihoods in Tanzania.
Linking science with stakeholders to sustain natural capital
(2007) Mwakalila, Shadrack; Burgess, Neil; Ricketts, Taylor; Olwero, Nasser; Swetnam, Ruth; Mbilinyi, Boniface; Marchant, Rob; Mtalo, Felix; White, Sue; Munishi, Pantaleo; Marshall, Andrew; Malimbwi, Rogers; Smith, Celina; Jambiya, George; Marshall, Andrew; Madoffe, Seif; Fisher, Brendan; Kajembe, George; Morse-Jones, Sian; Kulindwa, Kassim; Green, Jonathan; Balmford, Andrew
Monitoring forest carbon in a Tanzanian woodland using interferometric SAR: a novel methodology for REDD+
(Springer, 2015) Solberg, Svein; Gizachew, Belachew; Næsset, Erik; Gobakken, Terje; Bollandsås, Ole Martin; Mauya, Ernest William; Olsson, Håkan; Malimbwi, Rogers; Zahabu, Eliakimu
Background: REDD+ implementation requires establishment of a system for measuring, reporting and verification (MRV) of forest carbon changes. A challenge for MRV is the lack of satellite based methods that can track not only deforestation, but also degradation and forest growth, as well as a lack of historical data that can serve as a basis for a reference emission level. Working in a miombo woodland in Tanzania, we here aim at demonstrating a novel 3D satellite approach based on interferometric processing of radar imagery (InSAR). Results: Forest carbon changes are derived from changes in the forest canopy height obtained from InSAR, i.e. decreases represent carbon loss from logging and increases represent carbon sequestration through forest growth. We fitted a model of above-ground biomass (AGB) against InSAR height, and used this to convert height changes to biomass and carbon changes. The relationship between AGB and InSAR height was weak, as the individual plots were widely scattered around the model fit. However, we consider the approach to be unique and feasible for large-scale MRV efforts in REDD+ because the low accuracy was attributable partly to small plots and other limitations in the data set, and partly to a random pixel-to-pixel variation in trunk forms. Further processing of the InSAR data provides data on the categories of forest change. The combination of InSAR data from the Shuttle RADAR Topography Mission (SRTM) and the TanDEM-X satellite mission provided both historic baseline of change for the period 2000–2011, as well as annual change 2011–2012. Conclusions: A 3D data set from InSAR is a promising tool for MRV in REDD+. The temporal changes seen by InSAR data corresponded well with, but largely supplemented, the changes derived from Landsat data.
Procedures for quantification of belowground biomass of three mangrove tree species
(Springer Science, 2015-02) Njana, Marco Andrew; Eid, Tron; Zahabu, Eliakimu; Malimbwi, Rogers
A review of studies on belowground biomass (BGB) of mangroves revealed that proce- dures for excavation and determination of dry weight are insufficiently documented. The main objective of this study was therefore to describe procedures for quantification of tree BGB for Avicennia marina (Forssk.), Sonneratia alba J. Smith and Rhizophora mucronata Lam. The study covered four sites in Tanzania where 30 trees were sampled (10 for each species). A new root sampling procedure applied for A. marina and S. alba seemed to work adequately. Dry to fresh weight ratios (DF-ratios) varied between tree species, between tree sizes and between root compo- nents. Therefore, for each tree species, tree- and root component-specific DF-ratios were applied for dry weight determination. For A. marina and S. alba trees, a significant proportion of total tree BGB is stored in the root crown (34 and 10 % respectively). Future studies should therefore ensure inclusion of root crown when accounting for total tree BGB.
A report to the food and agriculture organization of the united nations (FAO) in support of sampling study for National Forestry Resources Monitoring and Assessment (NAFORMA) in Tanzania
(FAO, 2010) Tomppo, Erkki; Katila, Matti; Makisara, Kai; Per ̈asaari, Jouni; Malimbwi, Rogers; Chamuya, Nurudin; Otieno, Jared; Dalsgaard, Søren; Leppanen, Mikko
The Food and Agriculture Organization of the United Nations (FAO) has collected global level forest in- formation since 1947. UN-ECE/FAO (United Nations Economic Commission for Europe/FAO) has co- operated with FAO in collecting and publishing the Temperate and Boreal region data (UN-ECE/FAO, 2000). The most recent report, FRA 2005 was published in late 2005 (FAO 2005). Forest resources assessment is based mainly on National Forest Inventories (NFI) conducted at national and sub-national levels. Countries are planning and conducting the inventories on the basis of their own information needs and traditions. Some countries have long traditions, from the beginning of 1920s, while other countries have conducted just one inventory or are even planning the first sampling based inventory, or at a global level, are lacking even the first inventory. While some inventories are wood production oriented, some other inventories are targeted to produce information about non-wood goods and services, or are multi-purpose inventories. Most inventories collect information on the same base variables; however, some inventories collect some hundreds of parameters measured on the field (Tomppo and Andersson 2008). During the past 10 years, The Forestry Department of FAO has invested substantial resources to develop a programme of support to national forest monitoring and assessment (NFMA) (Saket et al. 2010). NFMA operates is mainly that of countries in development. Technical, financial and institutional capacity are often needed.
A sampling design for a large area forest inventory: case Tanzania
(NRC Research Press, 2014-04-21) Tomppo, Erkki; Malimbwi, Rogers; Katila, Matti; Mäkisara, Kai; Chamuya, Nurdin; Zahabu, Eliakimu; Otieno, Jared; Henttonen, Helena M.
Methods for constructing a sampling design for large area forest inventories are presented. The methods, data sets used, and the procedures are demonstrated in a real setting: constructing a sampling design for the first national forest inventory for Tanzania. The approach of the paper constructs a spatial model of forests, landscape, and land use. Sampling errors of the key parameters as well as the field measurement costs of the inventory were estimated using sampling simulation on data. Forests and land use often vary within a country or an area of interest, implying that stratified sampling is an efficient inventory design. Double sampling for stratification was taken for the statistical framework. The work was motivated by the approach used by The Food and Agriculture Organization of the United Nations (FAO) in supporting nations to establish forest inventories. The approach taken deviates significantly from the traditional FAO approaches, making it possible to calculate forest resource estimates at the subnational level without increasing the costs.