Tropical forest management and rehabilitation as means of biodiversity conservation in Africa

Researcher in charge: Olavi Luukkanen

Funding period:1997– 2002

Funding source: Finnish Academy, Finnish Graduate School of Forest Sciences.

Partners: Sokoine Agricultural University (Tanzania); Ethiopian Agricultural Research Organisation (Ethiopia); Forest Research Institute of Ghana (FORIG), Kumasi, Ghana

Abstract

From 1997-1999 this project aimed at analysing and providing guidelines for agroforestry development in the East Usambaras, Tanzania, as a tool for improved conservation of mountain rainforests, especially focusing on cardamom cultivation.

From 2000-2002, additionally these aims were included in studies on biodiversity rehabilitation of the Ethiopian highlands using fast-growing plantation trees as nurse crops, as well as in those on domestication of Iroko (Milicia excelsa) in Ghana, also involving smallholders in germplasm conservation that also increased their incomes by improving the farming systems.

From 2003-2008 the research in Tanzania was continued under a separate project led by Teija Reyes and financed by the Finnish Graduate School of Forest Sciences.

Project components

Biodiversity management in the East Usambaras, Tanzania

In January 1998, the field work was started for a two-year project which ultimately aims at creating improved tools for management in one of the globally most important biodiversity conservation areas in the tropical zone. The East Usambaras in north-eastern Tanzania have an exceptionally high degree of endemism as a result of isolation during geological times.

Presently, the land-use pressure is high, and the needs of the farming communities in the areas surrounding the conservation forests must be considered in management decisions. This project is implemented jointly with researchers in Tanzania and other countries, and its immediate beneficiary is the ongoing, Finnish-supported East Usambara Catchment Forest Project.

The first part of the project focuses on the assessment of biodiversity and forest disturbance,so as to facilitate forest zoning for conservation; an attempt will also be made to model the successional development of woody plants.

The second part analyses the environmental history of the study area, covering society and ecological change, as well as the deforestation process. The third part, led by J.F. Kessy, will develop further community- based forest management models. In addition, research forimprovement of agroforestry systems in areas surrounding theconservation forests will also be carried out.

Master theses

Räisänen, S. 2001. Biodiversity in tropical agroforestry systems: on-farm case studies in the East Usambaras, Tanzania. Department of Forest Ecology, University of Helsinki. M.Sc. thesis.

Vihemäki, H. 2001. Black pepper (Piper nigrum L.) cultivation in the East Usambaras, Tanzania: associated tree species and their effects on agroforestry system management. Department of Forest Ecology, University of Helsinki. M.Sc. thesis.

Viisteensaari, J. 1999. The fate of an alien tree species in tropical conservation forest management: regeneration and dynamics of woody plant species in Maesopsis eminii plantations in the East Usambaras, Tanzania. Department of Forest Ecology, University of Helsinki. M.Sc. thesis.

Reviewed articles

Huang, W., Luukkanen, O., Johansson, S., Kaarakka, V., Räisänen, S. & Vihemäki, H. 2001. Agroforestry for biodiversity conservation of nature reserves: functional groups, identification and analysis. Agroforestry Systems 00:1-18. (in press). Abstract

Huang, W., Pohjonen V., Johansson, S., Luukkanen,O., Katigula, M.I.L. & Nashanda, M. 2001. Species diversity, forest structure and species composition in Tanzanian tropical forests. Forest Ecology and Management (in press). Abstract

Participatory forest management in Gwira-Banso, Ghana

The study was conducted within the Gwira-Banso Joint Forest Management Project in Ghana. Hundred farming households were interviewed. Problems relating to participation were identified and recommendations made on how local people can successfully been involved in the management of a timber concession area in the western region of Ghana.

The project was established in 1995 as business co-operation between Dalhoff Larsen & Horneman A/S (DLH) and Ghana Primewood Product Ltd. (GAP), Ghana. The main objective of the project is to combine local people need for improve livelihood with the economic interest of DLH and GAP. The project has significantly improved local people’s livelihood by providing them with clean water, roads, and schools. In addition, some of the local farmers have been assisted to construct fishponds and snail farms. Free seedlings of black pepper and indigenous trees are also supplied to farmers. Another unique achievement is the development fund that has been established through the collection of US$ 5 fee per cubic meter of log extracted from the area. The co-operation between farmers in the area and the project initiators is very positive. However, long-term support of the local people for the project is crucial. Other main findings of the study suggest that a prerequisite for farmers long-term support for the reforestation on farmland will be to develop reliable and comparatively more productive farming systems that can integrate trees on farmland. Also Farmers need a guarantee of their legal rights to trees. Involvement of local people at all levels of the planning process is also emphasised in the study as a means to identify and meet local peoples needs. The study demonstrates that participation of local people is the best reliable tool for forest management in unreserved forest areas such as the Gwira-Banso concession.

Publications

Appiah, M. and Pedersen R. T., 1998. Participatory Forest Management in Gwira-Banso, Ghana. Department of Economics and Natural Resources, Royal Veterinary and Agricultural University, Denmark (M.Sc. thesis).

Appiah, M. 2002. Co-Partnership in Forest Management: The Gwira-Banso Joint Forest Management Project in Ghana. Submitted to Environment, Development and Sustainability 3(4): 343-360. Abstract

Conservation of Indigenous Tropical Tree Species in Ghana: Studies on Morphology and Physiology of Iroko (Milicia excelsa) 1999-2002

In 1995 Ghana Prime Wood Products Ltd. (GAP) and the Danish timber trading company Dalhoff Larsen and Horneman Ltd. (DLH), initiated a Joint Forest Management project to manage a 16,000 ha concession area in a lowland rainforest. The project, which is in collaboration with the local community of Gwira-Banso, undertakes forestry activities, which are supported financially by the Danish Government through DANIDA. Among the activities of the project, is the domestication of local tree species such as Iroko (Milicia excelsa of Moraceae family) in community farms and plantations. Iroko is a hard, all-purpose wood, which is used extensively in Ghana and accounts for a substantial portion of the timber export income of Ghana.

Poorly controlled use of natural forests and promotion of exotic trees in community-based land use have earlier characterised forestry activities in Ghana. Indigenous trees have not been sufficiently studied to ensure the protection of their genetic diversity or to allow their use in plantations and agroforestry for conservation and sustainable utilisation purposes. Previous socio-economic studies carried out on about 100 farming households indicated a high level of consciousness of forestry issues among rural people and willingness to adopt new forest management and agroforestry practices. The present studies will clarify the variation in different origins of Iroko using morphological and eco-physiological tree characteristics.

Results are expected to enhance the process of selection and practical forest management of selected species in different land use systems for the benefit of local people and to improve the ex-situ gene conservation of the Iroko tree species. So far, initial field results indicate that two years after planting in the field, the studied Iroko provenances had more than 50% survival across the three different ecological sites used in the study. Significant variation was observed between provenances of Iroko for height, diameter, branch angle, crown height, crown diameter, crown projection area and crown volume.

Biomass, gas exchange, leaf water relation and chlorophyll fluorescence studies are being carried out under greenhouse condition.

Publications

Appiah, M. and Pedersen R. T., 1998. Participatory Forest Management in Gwira-Banso, Ghana. Department of Economics and Natural Resources, Royal Veterinary and Agricultural University, Denmark (M.Sc. thesis).

Appiah, M. 2002. Co-Partnership in Forest Management: The Gwira-Banso Joint Forest Management Project in Ghana. Submitted to Environment, Development and Sustainability 3(4): 343-360. Abstract

Appiah, M., 2001. Conservation of Indigenous Tropical tree species: genetic variability in eleven provenances of Iroko (Milicia excelsa). Report title published in Tropical Forest Update, Vol. 11, Number 2 (ITTO).

Appiah, M., 2001. Crown characteristic in four Iroko (Milicia excelsa ) provenances grown in the dry semi-deciduous forest zone in Ghana. Ghana Journal of Forestry 11: 20-29.

Appiah, M., Koskela, J., Cobbinah, J, R., Luukkanen, O., 2001. Early growth performance of 11 Iroko (Milicia excelsa) provenances grown under different environmental conditions in Ghana. Ghana Journal of Forestry 11: 39-51.

Restoration of biodiversity on degraded highlands of Ethiopia by using plantation species as foster trees

The relatively early and extensive deforestation in Ethiopia, coupled with cultivation of steep marginal lands, overgrazing and socio-political instability, has resulted in severe land degradation over large areas of the country. We assume that, forest plantations established on degraded land long devoid of native tree cover can act as successional catalysts, facilitating the recolonisation of the woody native flora through their influence on understory microclimate and soil fertility, suppression of dominant grasses and provision of habitats for seed dispersing animals. Plantations can play an important role in restoring productivity, ecosystem stability and biological diversity of degraded lands.

The principal aim is to compare species diversity between degraded areas, plantations and natural forests as well as between plantations of different species, in a situation of severe tropical forest degradation. The influence of temporal variations, microclimate and physical factors on tree and shrub species diversity will also be studied. The seed dispersal mechanisms of the important local tree species will be clarified. Soil analysis will be conducted to clarify how plantations improve the edaphic conditions for the native flora invasion and subsequent re-establishment.

Combined with results from Tanzania and Ghana, the present research work will help in developing guidelines for forest plantation managers on enhancing the tree species richness of the extensive exotic monoculture forest plantations in Ethiopia. The results of this study will contribute to the conservation of the endangered and valuable native tree and shrub species in particular as well as other plant species in general. It will also help to develop practical methods of rehabilitating large bare and degraded areas in Ethiopia, and sites under similar conditions elsewhere.

Thesis

Yirdaw, E. 2002. Restoration of the native woody-species diversity, using plantation species as foster trees, in the degraded highlands of Ethiopia. Doctoral thesis. Univ. Helsinki Tropical Forestry Rep. 24.

The dissertation consisted of the following publications:

Yirdaw, E. 1996. Deforestation and forest plantations in Ethiopia. In: Palo, M. & Mery, G. (eds.). Sustainable forestry challenges for developing countries. Kluwer Academic Publishers, The Netherlands. Abstract

Yirdaw, E. 2002. Diversity of naturally-regenerated native woody species in forest plantations in the Ethiopian highlands. New Forests 22: 159-177. Abstract

Yirdaw, E. & Leinonen, K. 2002. Seed germination responses of four afromontane tree species to red/far-red ratio and temperature. Forest Ecology and Management 168: 53-61. Abstract

Yirdaw, E. & Luukkanen, O. 2003. Photosynthetically active radiation transmittance of forest plantation canopies in the Ethiopian highlands. Forest Ecology and management 188 (1-3): 1724. Abstract

Yirdaw, E. & Luukkanen, O. 2002. Indigenous woody species diversity in Eucalyptus globulus Labill. Ssp. Globulus plantations in the Ethiopian highlands. Biodiversity and Conservation 12 (3): 567-582. Abstract

Other related publications

Yirdaw, E.1996. Deforestation in tropical Africa. In: Palo, M. & Mery, G. (eds.). Sustainable forestry challenges for developing countries. Kluwer Academic Publishers, The Netherlands. Abstract

Yirdaw, E & Palo, M. 1996. Deforestation and sustainable forestry challenge in Ghana. In: Palo, M. & Mery, G. (eds.). Sustainable forestry challenges for developing countries. Kluwer Academic Publishers, The Netherlands. Abstract

Yirdaw, E. 1999. Restoration of biodiversity on degraded lands of Ethiopia through the use of forest plantations. World forests, Society and Environment Volume III. Kluwer Academic Publishers, The Netherlands.