TROPICAL SECONDARY FOREST MANAGEMENT IN AFRICA:
Botswana Country Paper
Mosegofatsi Sedi Bose
Ministry of Agriculture
Department of Crop Production and Forestry
P/Bag 032, Kanye, Botswana
Tel. +267 5440 346; Fax. +267 5441 510
WORKSHOP ON TROPICAL SECONDARY FOREST MANAGEMENT IN AFRICA:
In collaboration with ICRAF and CIFOR
Nairobi, Kenya, 9-13 December 2002
The incidence of secondary forests (as defined in this paper) in Botswana is not significant at national level; it is mainly confined to areas which were used for arable field crops. However, frequent fires, overgrazing, and fuelwood collection has rendered most of the natural forests around human settlements to conform to the definitions of secondary forests.
A large portion of these forests falls under tribal land territory and hence is legally accessible to all citizens of Botswana. The economic value of these forests can never be overemphasised; they provide a variety of foods for subsistence, medicine, fuelwood, handicrafts and a service of biodiversity conservation.
However, it is unfortunate that management of secondary forests on Botswana is almost non-existent. This is in spite of cultural safeguards such as not cutting live trees for firewood and selecting certain species for firewood. The major management tool is the construction of a network of firebreaks all over the country. Another major activity is fighting of veld fires by community volunteer fire fighters and currently an initiative to form village conservation committees which will be in charge of the local forested areas.
The political and legal framework in the country has adequately addressed the conservation of the forest resources. This is evidenced and documented by the number and existence of many acts and policies dealing with this important resource. However, these legal instruments are rendered ineffective or difficult to implement because of the land tenure system. Another source of concern is that these acts are housed under different Ministries, making implementation, coordination and cooperation ineffective because of the perceived independence and competition by the Ministries. However the government is currently addressing this problem by making a major restructuring of ministerial portfolios resulting in creation of new Ministries.
This paper demonstrates that the secondary forests, as part of the natural forests, provide a base for rural development, conservation of both animal and plant diversity. They also provide alternatives for subsistence food, medicine, and firewood and income generation, thus improving the socio-economic status of the country. The status quo is not bound to change at least for the next ten years. This reasoning implies a need for setting up structures that will be responsible for the management of the forests rather than `letting nature to take its course.' This will of course require co-operation and major consultation between all stakeholders.
Another important step will be the institutionalisation of integrated forest management. The government and non-governmental institutions dealing with the management of forests should be strengthened so that they can meet the current needs. This will facilitate documentation and research on the importance, extent and value of the resources of the forest base and all its development stages, in the country.
Botswana is situated between 20º and 30º east and 17º and 27º south. The mean altitude is 1000 m above sea level and the total land area is 582 000 km². Natural forests (minimum area of 0.5 ha, attainable minimum tree height of 5 m, and 10 per cent crown cover, after FAO, 1993) cover 26.19 million ha, i.e. 45 per cent of the total land area. Natural forest includes 25 per cent closed forest (6.55 million ha) and 20 per cent woodland (5.24 million ha). Tree plantations cover a negligible 1200 ha (FAO FRA 2000 home page; FOSA national reports).
It is a landlocked country with Namibia (west), Zambia (north), Zimbabwe (northeast) and South Africa (southeast and south) as its neighbours. The socio-economics of Botswana is determined by a variety of factors (World Resources Institute, 1994). It is mainly arid (62 per cent of the country, with growing season <76 days per year) to semi-arid (38 per cent of country with 76 to 120 days growing season). The population was 1.24 million in 1990, with 31 per cent urbanized. The population is concentrated in the eastern part of the country. The GDP in 1990 was US$2893 per capita, with 58 per cent contribution from industry and 36 per cent from services. Agriculture contributes a small 6 per cent. It is a middle-income country with one of the strongest economies in southern Africa, mainly because of its mining industry.
Topographically the country is a tableland and can be divided into two regions:
The climate is generally subtropical, but ranges from continental to semi-arid. About 90 per cent of the rainfall occurs in the summer (November to April), peaking in January and February. Botswana is prone to droughts that extend over a number of years. Three rainfall regions are recognized:
This paper seeks to gather, analyse and make available knowledge on the current status, trends and extent of tropical secondary forests in Botswana: processes of formation and transformation, use patterns, social, economic and environmental importance, and management practices. It also provides an inventory and discussion of current policies, development actions for such policies, actions needed for the better management of the resource, and constraints and issues in forest management in general. Lastly, it identifies constraints and challenges, and recommends priority actions needed for the better management and sustainable use of the forest resource.
The vegetation, and particularly `forest' vegetation, is very much determined (limited) by the climate (mainly rainfall), and various edaphic and biotic factors. The vegetation of Botswana is composed of 60.8 per cent arid woodland, 33.2 per cent moist woodland, 4.4 per cent arid and moist grassland, and 1.6 per cent wetland (Kruger et al, 1994). The Vegetation Map of Africa (White, 1983) shows the following main vegetation units for Botswana:
The definition used in this paper for Secondary forests is "...forests regenerating largely through natural processes after significant human disturbance of the original forest vegetation at a single point in time or over an extended period, and displaying a major change in the forest structure and/or canopy species composition with respect to nearby primary forests on similar sites." Secondary forests (forest succession vegetation) have the following characteristics (according to the Terms of Reference for the Workshop):
The main conversion of natural forests was through land clearing for agriculture and/or livestock husbandry and unplanned and intensive tree extraction for structural timber. Fire was usually applied as a cheap and fast means of clearing large tracts of land for production systems and controlling pests like ticks. At local level, around forested areas, the decline of natural forests can be attributed to cutting and logging for firewood, building and construction and uncontrolled forest fires. The economic and environmental impacts on primary forests in the landscape, through tree and timber cutting, and farmers' crop and livestock production systems remain largely unknown.
The extent and characteristics of secondary forests in Botswana has never been documented. Nevertheless, the data available can be used as a reasonable baseline/yardstick for action or at least discussion. Approximately 10.48 million ha (18 per cent of the country) is classified as degraded and an additional 6.4 per cent of the country suffers from bush encroachment (Squazzin and Du Toit, 1998). The areas worst affected are commercial farms and areas around boreholes and watering points for livestock. In some areas, the thorny bushes grow so closely together that people and animals cannot move through. The indicator tree species for this bush encroachment are Acacia tortilis, A. mellifera, Dichrostachys cinerea and Terminalia sericea. These statistics summarise the extent and character of secondary forests at national level. However there are marked differences at local level.
The population of the country was historically quite low. The conversion from forests to other types of land use was not a problem. However, since independence, the population growth rate increased (3.5 per cent). This increased the pressure on the forests to satisfy the demands for fields, building poles, fuelwood, and non-timber forest products. This pressure is expected to continue even though the population growth rate has gone down to about 1.91 per cent in the 1995 to 2000 period (CSO, 2002). In some areas Mopane woodlands were reduced to shrub mopane.
There is a perception that at national level Botswana has a net surplus of firewood. However, there is an increasing problem of serious degradation related to collection of firewood, especially around the larger villages and towns. Poverty and lack of substitutes for fuelwood in these areas are causing this problem. It has been estimated that 9831 ha of forest land is cut deliberately for fuelwood production per year. This phenomenon can be witnessed along the roads during the winter season when fuelwood demand is high (NRTP, 2000). It has also been confirmed by surveys at Makomoto, Central District and the Kweneng Districts. Unfortunately, the impact of this at national level has not been researched on or quantified. In some areas post-extraction secondary forest has developed (often called bush encroachment), but in many areas the degradation continues.
Forest fires contribute a lot to the destruction of the natural forest resource. Control of damaging fires could help forest recovery through the formation of secondary forests (where the forest structure and composition were severely altered). For example, about 65 000 ha were burnt in Southern Region during the fire season April to November 1998. In addition, 156 forest fire incidents were recorded from January to 23 August 2002, burning an area of 402 876 ha with loss of property. The hardest hit Districts were Southern (51 fires), Kweneng (31 fires), Ngamiland (13 fires), Central (15 fires) and Kgalagadi (14 fires) regions.
Fire is also a significant factor in forest reserve management, and impact on the only commercially exploitable timber trees. As far back as 1935 foresters in Chobe noted that, "There is ample proof throughout the concession area of the damage caused by man and animals, by insects, drought, frost and wind, but the combined damage from these causes is insignificant compared with the disastrous effects of fire." Nothing has changed today. "Fire has been and is still one of the worst threats to the forests of Botswana" (Gombalume and Manthe, 1995).
For Pterocarpus angolensis (the most valuable timber species in the forest reserves) the problem is compounded by elephant damage. The bark of mature trees is naturally resistant to the regular fires. However, the increasing elephant population has increased the instances of bark peeling of this species. With the bark removed the trees have no protection from fire. Healthier populations of the species occur in areas where the elephant population is lower (Burger, 1993).
Most of the woodlands of Botswana are located on tribal land. However, the most significant factor, which contributed to post abandonment forests, is conversion of forested areas to agricultural lands. It is hard to get the actual size of this secondary forest type. However, some agriculture statistics may indicate the extent of this type of secondary forest. For example, about 490 965 ha of crops were planted in the 1995/96 season while only 170 300 ha during 2001/02 year. The unutilised arable lands have mostly regenerated and formed secondary forest vegetation.
It must be noted that the information provided in this section does not distinguish between primary and secondary forest. Secondary forest has never been considered as an independent entity or land/forest management category in Botswana. Therefore, most of the data cuts across all forest types. Again, a major shortcoming is lack of definitive/accurate data as opposed to generalisations (rank speculation in some cases). The importance of secondary forests for environmental services is not yet assessed in Botswana.
It is estimated that Botswana currently consumes more woodfuel than it is replaced naturally: 2 014 000 m³ for consumption and 1 993 000 m³ of production (from Wood and Wood Product Supply and Demand in Africa to 2030, working paper for FAO, May 2001). These figures demonstrate the unsustainable exploitation of the resource at national level.
The following products are harvested from the forests as food sources for both subsistence and commercial purposes.
(i) Schinziophyton (Ricinidendron) rautnenii: A large spreading tree, 15-20 m in height, occurring on wooded hills and among sand dunes, always on Kgalagadi sand and sometimes forming pure stands (Palgrave, 1997). The fruits are 3.5 cm long and 2.5 cm in diameter with a mass of about 10 g. The flesh is 2-3 cm thick and surrounds a hard-shelled seed. The fruit and nut are edible and highly nutritious. Perkins (1999) described the nutrient content of the fruit as "...very sweet flesh with up to 30 per cent sucrose, good source of magnesium, potassium, carbohydrate, energy and thiamin, with small amounts of vitamin C. The nut is nutritionally rich, high in protein and oil content, linoleic acid 42 per cent and oleic acid (18 per cent), with a high energy value, and rich in minerals and riboflavin."
(ii) Sclerocarya birrea subsp caffra: Only female trees produce fruit. The fruits are 3-5 cm long, and 2-3 cm in diameter. A tree can produce up to 550 kg of fruit per year. The fruit has a high moisture and vitamin C content. The pulp is used to brew beer, fruit juice, jam and jelly. The seeds (two per fruit) taste like walnut and are highly nutritious.
(iii) Colophospermum mopane: The mopane tree is host to the Imbrasia belina moth. The moth lays eggs on trees in the widely available mopane woodland. The larvae (worms) feed on the leaves of the host tree and are harvested for human consumption. The `worm' is then cooked and spiced (usually with salt) and dried for packaging and sale to urban centres. The `mopane-worm' business is well established and provides seasonal employment to many rural households. The export business (mainly to South Africa) was valued at 7 366 738 pula (or US$1.3 million at current rates) in 1993 (CSO, 2000).
(iv) Strychnos cocculoides: The fruits are circular and 6.5-10 cm in diameter, with a woody brittle shell 3-4 mm thick, encasing a sweet, pleasantly flavoured pulp in which numerous seeds are embedded (Perkins, 1999). The fruits are sold in the informal market, as it is the case with most indigenous fruits.
(v) Grewia spp: Twelve species are found in Botswana of which only four (Grewia bicolor, G. flava, G. flavescens and G. retinervis) are highly sought after. It forms a significant part of the diet because of availability. The fruit can be preserved by drying. It is also used to make nicely flavoured beer.
There is a host of other trees and plants that are used as food source in Botswana (Venter and Venter, 1996) and they are, amongst others, Adansonia digitata (Baobao fruits), Bauhinia petersiana (Wild coffee bean), Mimusops zeyheri (fruit), Vangueria infausta (fruit), Tylosema esculetum (Morama beans), Citrillus lanatus (Wild melon), Terfezia pfeilii (Kgalagadi desert truffles), gums, and mushrooms.
The forests in Botswana have numerous plants, which have been used as traditional medicine for many ailments. However, there is scanty local documentation on these plants. Traditional medicine practitioners often keep their knowledge secret. Nevertheless, Perkins (1999) notes that there are about 130 such plants in neighbouring South Africa, which should be comparable to Botswana.
The most documented and widely used plant in Botswana is devil's claw (Harpagophytum procumbens). Its tubers are cut, dried and finally processed and consumed as tea, capsules and tablets. The treatments have been proven to be an effective remedy for arthritic pain, diabetes, gall bladder, liver and kidney complaints. Lastly, there are three herbal teas (Artemisia afra, Lippia javanica and Lippia scaberrima) that are packaged and have established markets.
Most trees are used to make crafts for domestic use and for sale. However, the fan palm (Hyphaene petersiana) is the most significant at national level. This plant is the backbone of the famous Botswana basket industry which is also closely linked to tourism. The leaves of this palm are torn into strips to make the baskets. They are usually boiled with roots of mainly Berchemia discolor, Terminalia sericea and Euclea spp to add colour and decor on the final product. The mature palms are also tapped for an intoxicating palm wine.
The idea of secondary forests has not gained much recognition as yet, hence lack of both knowledge and/or experience in the management of these forests. The current management experience is that of sporadic exploitation because it seems like the current view is that `secondary forests are a free resource and can be exploited anyhow.'
Development of agricultural schemes caused the elimination of natural tree formations. This led to increased erosion and subsequent loss in ecosystem productivity and formation of secondary forests (when the schemes were abandoned). However, some of the agricultural fields are being re-used in areas where secondary forests have restored the productivity of the land.
Fires, mostly emanating from human activities, destroy vast areas annually. In the process, there is significant loss of biological diversity in terms of animal species, ecosystems and genetic variations. This is no exception for forests.
There is also a considerable damage by wildlife, particularly elephants, in the extreme north-east and to a lesser extent in the eastern part of the country (Burger, 1993). However, this problem continues because elephants are a tourism attraction, are internationally protected, and the culling of excess elephants has been phased off.
The most obvious management practices are linked to cultural and religious belief systems and perceptions. The most influential cultural practice has been the exclusive use of dead trees for firewood. This is very important in management terms because biomass energy is mainly consumed as firewood (Afrane-Okese, 2001). Consumption of other forms of energy, like charcoal, is non-existent. Afrane-Okese (2001) also states that in 1991, firewood accounted for 57 per cent of the national energy consumption. This figure is however, decreasing as the economy grows and people start using substitutes like cooking gas and electricity. The current contribution of firewood biomass to national energy has fallen to about 30 percent.
The complications brought about by the Land tenure system after independence has resulted in slackening of traditional management systems. This is especially true for tribal land where the forest resource is now accessible to everyone with little regard to conservation or sustainability. However, there have been some important endeavours in the management of forests, even though they are insignificant at national level. These include formation of village conservation committees and volunteer fire fighters around the country. The formation of village boards (Trusts) is another form of management that are mainly based on wildlife utilisation and management. The use of other forest products in this management system is just complementary.
The land use system can be traced to colonial times when tribal Chiefs were custodians of the land. This was the period before the advent of Land Boards after independence in 1966. The Chiefs were land overseers and had `sweeping powers' enabling them to control the production areas, fields, grazing land and forests in their tribal territory. However, in 1973, the power of the chiefs was usurped by the Land Boards which were given the power to allocate, administer and manage land which was previously under control of the tribal authorities.
It comprises about 55 per cent of the total National land area. There are 12 land boards holding all communal land in trust for the citizens of Botswana and allocate it for residential, commercial and agriculture uses. Everybody is legally entitled to own communal land for own use. On allocation, the holder does not pay any price for the land and does not acquire any exclusive rights or perpetual rights to it. However, if the land is used for the allocated purpose it stays in the family indefinitely and is used as if exclusive rights and perpetual rights have been attained. In 1995 large chunks of this land (24 per cent) was designated and zoned as Wildlife Management Areas (WMAs). Therefore, in legal terms tribal land used to cover about 79 per cent of the total area.
The owner has perpetual and exclusive rights to the land, including natural resources within the land, with exception of Wildlife. It comprises about 3 per cent of the total land area in designated blocks along the eastern and southern parts of the country. There are also some blocks in the western part of the country. This area is most suitable for agricultural land. Most of the freehold farms are dominated by private commercial farms, which are dominated by the livestock sector.
It comprises 42 per cent of the total land area. It consists of land that the government has reserved for conservation purposes and land covered by ranches of the Botswana Livestock Development Corporation (BLDC). Conservation areas cover about 98 per cent of the state land. These areas include National Parks and Game reserves, forest reserves and other wildlife sanctuaries. A major increase of this land (24 per cent) was gained from communal land in 1995 as parcels of land close to protected areas were declared Wildlife Management Areas (WMAs). The land use type for WMAs is an integrated one as it encompasses hunting, game ranching, farming and live-capture of animals. These areas also act as buffer zones between conservation areas (National Parks and Game Reserves) and areas of intensive agriculture use.
The acts discussed below were found to be the most relevant in the management of forests in Botswana, including secondary forests.
This act provides for the conservation and improvement of the agricultural resources of Botswana. Agricultural resources are defined to include soils, waters, plant life, fauna, vegetation and vegetable products and such other things declared by the Minister. The Agricultural Resources Board is vested with powers geared towards the conservation of the agricultural resources. The Board may issue orders to the owner or occupier of the land to conserve the agricultural resources or make regulations to regulate agricultural land use practices in designated areas. The Board is empowered to issue conservation orders and stock control orders. In the event that the administrative orders are not complied with, criminal sanctions may be applied.
The Act provides for the better regulation and protection of forests and forest produce in Botswana. The President is empowered to declare any area on State land to be a forest reserve. A local authority or land board may propose that a forest reserve be established on any area or land in its area. An order may provide for the protection, control and management of such forest reserve and shall be subject to control by the forest officer. The Minister may declare any tree to be a protected tree and a licence is required to fell, cut or remove the tree. There are prohibited acts in the forest reserve and on state land. For example, the Forest Act states that:
(a) No person shall fell, cut, take, burn, injure or remove any forest produce
(b) Set fire to any grass or undergrowth, or light or assist in lighting any fire or leave unattended a fire which he has lit, or caused by his negligence, before such a fire has been thoroughly extinguished or leave therein any object likely to cause a fire unless he holds a license to do otherwise from the forest authority.
Licenses may be issued to persons to do otherwise prohibited actions in the forest reserves. Penalties are provided for commission of forest offences. Enforcement powers, such as search and arrest without warrant and seizure of property, are provided in the act to protect forests. Any person who contravenes the conditions on any license issued to him/her under the Forest Act shall be guilty of an offence and liable to a fine not exceeding P5000 or imprisonment for the term not exceeding 2 years or to both and if he/she is not the holder of a license, the forfeiture of such a license in future.
This act provides for the declaration of national parks and game reserves, the conservation and management of wildlife, the protection and preservation therein of wild animal life, and for the establishment, control and management of the declared national parks and game reserves. Provision is made for the declaration of Wildlife Management Areas and Controlled Hunting areas under this act. Protected game animals are specified in the Schedules of the act. Licenses and permits are issued for hunting and capturing activities. Enforcement powers are provided to Wildlife Officers to enable them to perform their duties under this act. The Act provides for the prohibition, restriction, control or regulation of the burning of vegetation or felling cutting and removal of trees therein or there from. The act also states that no one can willingly cause a veld-fire in a National Park. Any person who contravenes or fails to comply with any other provisions of the Act shall be guilty of an offence and without derogation from his liability under any other provisions of the Act, shall be liable to a fine of P2000 and to imprisonment for two years.
This act provides for the orderly and progressive development of land, both in urban and rural areas, and to preserve amenities thereof, for the grant of permission to develop land and for the powers of control over use of land. The Minister may declare planning areas to which the provisions of the act may apply, and has to prepare a development plan indicating how the land in the planning area may be used. The plan may define sites for proposed roads, public and other buildings or works, airfields, parks, pleasure grounds, nature reserves, open spaces and allocate areas for forestry, mining, water resource, industrial etc. The Minister may in the interest of amenity, make provision for the preservation of trees or woodlands in any area. The act uses the enforcement notices to defaulters, as well as penalties in contravention of enforcement notices.
The act provides for the establishment of tribal land boards. It also defines the powers and duties of the Land Boards. They hold land in trust on behalf of the citizens of Botswana and for the purpose of promoting the economic and social development of the people. The land board's functions in relation to customary tenure of land include the grant and cancellation of the rights to use the land, the imposition of restrictions to use land, authorising a change of user of tribal land and transfer of tribal land. The land board is required to define land use zones and submit for determinations to the Minister. The land board makes grants of land for any land use in conformity with the use for which the land is zoned. There is provision on offences and penalties for contravention of the act.
The human influence on forests, including secondary forests, in the country is at its highest point. However, forests will continue to contribute directly and indirectly to the national economy even in the long-term. The forest is a very important economic base, especially for rural livelihoods.
There is a serious lack in institutional capability and capacity in the inventory, research and monitoring of the forest resource base. Consequently, the value of forests in general, and secondary forests in particular, in economic and ecological terms has gone unreported and is not quantified. The secondary forests in Botswana are under unprecedented threat of further degradation because they are viewed as a `free' resource.
Nevertheless, these forests offer many important services like food, construction material, traditional medicine and a wide array of other domestic needs. They also meet other broad-base objectives/services such as environmental protection, tourism and conservation of bio-diversity and ecosystems.
It has also been demonstrated that the legal system in Botswana can be used to address the utility and conservation of forests. However, the institutional set-up is so fragmented to the extent that the legal instruments are difficult to implement. The government structures dealing with management of forests work more or less independently of each other. The inadequacy of communication and consultation results in people and departments often working in isolation. These problems need to be addressed effectively if all the laid out policies are to achieve the desired results. In conclusion, there is a serious need for collaborative management and co-operation from all stakeholders for the legal instruments to be applied for better stewardship of the country's forests, and those secondary forests that are in a state of recovery after serious degradation.
The first recommendation is that the integrated forest management approach should be institutionalised. This will foster the need for co-operation and collaboration by all concerned stakeholders. The method of exploitation of the forests should be scrutinised with the ultimate goal of giving more responsibility and legal authority to communities residing in the vicinity of the forest. Also the rural communities must have a fair share in the distribution of benefits accrued from the forest resource, to prevent further degradation and to facilitate recovery through secondary forest development. Empowerment of communities (especially continuity over generations) should encourage better stewardship of the resource over time.
Secondly, there is a serious need for capacity building/strengthening of relevant institutions for the control, management and protection of forest resources at local level. This should also include intensified extension and education programs on the utility and the need for conservation of secondary forests.
Lastly, the government should strongly and systematically start to encourage and support farmers to increase the planting of small tree lots around homesteads, along linear features such as roads, rivers, boundaries (hedges, shelter-belts and fences) and fields (agroforestry systems). If executed successfully, such planting can help to reduce pressure on natural forests and woodlands, to enhance environmental conservation, to increase food production through planting of food-yielding and multipurpose trees, and to increase wood production.
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