Deforestation Pressures in Ghana

8/6/2019 Deforestation Pressures in Ghana

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GEOG 306/4-AA Term Project #3

Deforestation Pressures and Impacts in GhanaJane Sorensen, 3031284

March 28, 1995The current rate of deforestation in Ghana (defined as permanent removal of forest for land use inshifting cultivation, permanent agriculture, or settlements) is about 22,000 ha or 0.8Z of the totalforest per year [Note: this figure shows that the total forest cover is 2.75 million ha, in the first yearof calculation. If the rate continues at 22,000 ha/y, the percentage of deforestation rate increases].2,000 hectares of plantation are established each year (World Resources, 1990-91). Wagner andCobbinah state that the deforestation rate for 1981-1985 was 1.3Z annually, but they also concedethat this was a considerable decrease compared to peak years in the 1970s. The pace ofdeforestation is apparently slowing down, and the government would like to see sustainability oreven net reforestation. This may not be likely considering demographicsboth population andurbanization are increasing (Kurian, 1992).

Outside government control, however, reserve areas have suffered from illegal logging. Forestryofficials in Ghana estimate that as much as $50 million of wood is illegally exported from Ghanaper year (Myers, 1992). This figure cannot be translated with the information obtained into cubicmeters or estimated area deforested. It is sufficient to say that the majority of deforestation inGhana has resulted from overexploitation and conversion to agriculture, and that this seems to bethe largest continuing, if not only, danger.

Physical ImpactsIn a highly technical paper on the mineralogy and geochemistry of tropical rain forest soils, inwhich the study site was the Ashanti timber reserve in southwest Ghana, a few pertinent

observations were made. This area is within the inner tropical zone of partial plantation [cf. Butt,1987, in Bowell, 1993], where highly leached soils occur. It is considered a consequence of partialplantation that the soils on the upland slopes of the area are relatively thin, due to the removal ofsoil in the wet season. The Ashanti area was an exception, with some soil profiles being 7-10 mthick. In a warm, wet tropical rain forest terrain, chemical weathering is a relatively fast process,and when mineral weathering is coupled with organic decomposition, there is a rapid andconsiderable accumulation of feralsol soils. These do not harden on exposure as do the moreextensively leached laterite soils (probably making these soils more sustainable or more suited toagriculture than other converted lands). It was also noted that the absence of certain oxides in theAshanti soils indicated that there has not been the extreme leaching associated with soils in Brazil,South Africa, or eastern Australia (Bowell, 1993).

The erosion rate for tropical rain forest biomes is estimated at 50 m per million years. Sedimentcores of Lake Botsumtwi have been analyzed and it seems that the current tropical climate and highrainfall are fairly recent (about 9000 years old), preceded by savannah. The formation of the soilprofile has been estimated to proceed at 200-300 m per million years (Bowell, 1993). If this land isdeforested, therefore, the soil is not likely to suffer the way it has in other case studies.

Manns (1990) review of deforestation, traditional farming, and climatic change in Africa coveredGhana as a case study. Ghana experienced a severe drought in 1983. Bush fires were rampant in the


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countryside, destroying valuable woodland, farms and forestry plantations. Rainfall was decreasedover protracted periods of time compared to previous decades. Even in the rainforest zone, thewater table was depressed and water shortages were an urgent problem. The rains in 1987 werereported two months late throughout the country. Forest zone farmers were remarking that rainswere heavier and commenced earlier in the past, when there was more tree cover (Mann, 1990).

In the eastern region of Ghana, the rains have decreased by 60g since 1965, the year the Akosombodam was completed. Many farms have been abandoned due to low rainfall. Lake Botsumtwi isevaporating faster than it is being replenished by rainfall, that is, the lake level fell by 2.4 mbetween 1972 and 1987. The surrounding hills have been progressively deforested. The riverAyensu, which rises from many tributaries from within the remaining rainforest, displayed areduced flow in each dry season since 1981-82. A reservoir that was calculated, in April 1987, tohave sufficient water for three months, ran dry a mere two weeks later. In the north, increasedaridity is exacerbated by the large-scale annual burning of grass and woodlands. Uncontrolledburning creates soil erosion, depletes soil fertility and degrades forests (Mann, 1990).

The following is an example to illustrate how a forest can help prevent aridity: On the eighth ofMay, 1987 at Yendi Agricultural Station, the bare ground temperature was an average of 67Cfrom 10 am to 5 pm, with a midday peak of 72C. Under the shade of trees at the same site, themaximum temperature was 40C. When vegetation cover is removed, albedo increases, surfacetemperature increases, and dust in the upper troposphere accumulates. This change in the energybudget theoretically intensifies the downward motion of the air in the upper troposphere, whichleads to compression and warming of the lower air masses. This pattern may tend to prevent theformation of rain-clouds, and it interrupts the progress of monsoon systems. Meteorologistsestimate that 250,000 km2 of forest must be removed in a region before climatic changes occur. InWest Africa, that figure has been exceeded several times over (Mann, 1990).

Cultural and Biological Impacts

Since the Ghanian declaration of independence from Britain almost four decades ago (it waspreviously known as the Gold Coast), the economy and the condition of most of its people havedeclined steadily, until the late 1980s (Kurian, 1992; Jamieson, 1993). The population has alsodoubled. As it will be shown, the largest danger to wildlife is the removal of habitat (Jamieson,1993; Fargey, 1992), and the largest danger to habitat, the forest, is population pressure (Mann,1990).

Cultural impacts and biological impacts causing or resulting from deforestation are almostinextricably intertwined. While certain cultural practices that sustain wildlife and the forest havebeen done away with, certain others have cropped up in their place. For instance, one tribal lawdictated that the tusks and ears of an elephant that is killed must be brought to the chief, but thechief no longer sanctions elephant killing. The wildlife and forest shrines are still widely respected,

and it is imperative that this cultural aspect is not lost (Jamieson, 1993).

A study on forest elephants in a Ghanaian rain forest fragment theorized that changes in selectivelogging regimes as a result of expanding international market for tropical hardwoods haveprofoundly altered forage availability for elephants in commercial forest reserves. The elephantsprefer secondary forest because of the relative accessibility of forage and for the succulent gapcolonizing species. The authors mention that fifty years ago, only one tree species was logged inGhana for the export market, but that now fifty species are heavily exploited. Some major timber


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species are important mast and fruiting trees. Mast species are infrequent but simultaneous fruiters;there are evolutionary advantages to this habit. If elephants are one of the methods these fruitingtrees have for seed dispersal, there will be an adverse effect if these trees are logged out of syncwith the masting or without regard for generation, or if other factors discourage the elephants fromforaging in that particular biome (Dudley, Mensah-Ntiamoah, and Kpelle, 1992).

For some communities, cash crops are the chief source of income for most households. This phraseseems to signal the danger of widespread deforestation in order to maximize economic benefit, butthere is no additional data on where the market for production lies or how much is exported outsidethe community. In fact, since the ability to rely on wild forest products in times of need is animportant asset of the community (Dei, 1989; Fargey, 1992), there is a chance that while certainareas may not be deforested, they may be overexploited in times of need or due to the expansion ofvillages (once again, it has been stated that the largest social threat to forested areas is populationincrease (Fargey, 1992)). Most food is gathered from the forest in these communities, such as roots,fibres, leaves, bark, fruits, seeds, nuts, crabs, insects, snails, molluscs, mushrooms, honey, sap andsyrup. Bush game is the most highly valued food and protein source, and although deforestation hasmade wildlife less plentiful now than in former times, game is not rare (Dei, 1988).

There has been increased exploitation of game, indicated by the change in morals from huntingonly old and infirm animals to including young and pregnant animals, and even animals that werepreviously forbidden as food. This occurred in the Boabeng-Fiema Monkey Sanctuary in the1970s, when Christian converts began killing monkeys to decry the traditional fetish rites. Thebiggest threat to the monkeys has already taken its toll: further expansion of the villages (Fargey,1992; Jamieson, 1993). Another reason for exploitation of previously ignored prey has beenattributed to the opening up of primary forest to secondary forest, making it easier for night huntersto capture game and also expanding trapping area, resulting in an overall decrease of game (Dei,1988). Ghanaians care about their forests and wildlife, but as an old Ashanti proverb states, Icannot be sympathetic to the antelope if there is no meat in my pot. (Jamieson, 1993).

Reducing the Pressure on Remaining ForestsConcerning the production of wood in wild habitat and/or production reserves for tropical moistforest, growth estimates of 3-6 cubic meters per hectare per year have been cited. The existingproduction-reserve tropical forests can be harvested at a rate of 1.4 million cubic meters per year,with complete sustainability, using a felling cycle of 60 years or longer. Annual harvests have beenbelow this volume since 1980, and peak timber harvests during the 1970s did not exceed 2 millioncubic meters annually (Wagner and Cobbinah, 1993).

It was elaborated in Myers book The Primary Source the amount of destruction or disturbanceselective logging can leave on the remaining forest community. Logging roads and skid paths, aswell as falling trees, can mar

previously healthy trees, exposing them to infection if not bleeding them to death. This effectdemonstrates that the low estimate of allowable cuts, compared to the estimate of annualproduction, is a prudent measure taken by the Ghanaian government and/or timber industry. Thefelling cycle was also recently extended from 25 to 40 years, which lengthens the recovery periodfrom logging (Wagner and Cobbinah, 1993).

There is a ban on the export of logs from twenty species that have resource life of 25 years or less.A resource life is the number of years that current extraction rates can continue before the standing


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volume of commercial size is depleted. The lowest figure quoted in a table in Wagner andCobbinah was for the species Milicia excelsa, common name Iroko, which has a resource life of 10years (Wagner and Cobbinah, 1993).

The forestry industry, third in contribution to Ghanas GDP, employs about 250 000 out of apopulation of 12 million. 7.5% of foreign exchange comes from the export of wood products.

Forest policies are structured to enhance value-added industries (how other countries co-operatewith Ghana will be a big factor here). 80% of the annual harvest is processed locally. Theprocessing industry is dominated by sawmills (100 of them), with 13 veneer plants, 9 plywoodmills, and one chipboard plant. There are no pulp mills, but this may change as the populationbecomes more literate. 50% of raw timber that is exported is of the abundant species, Triplochitonscleroxylon (Wagner and Cobbinah, 1993).

The current harvesting practice is to harvest the trees over the girth limit. It would be appropriate toleave residual over-mature trees in stands as seed sources and to preserve unique habitats.Secondary forests are preferable for logging interests, but a problem could be that greaterdisturbance will result at each forest entry, dramatically altering species composition. Managementof these secondary forests must improve, since they are a source of fuel wood, food, medicine, andconstruction materials (Wagner and Cobbinah, 1993). Harvesting secondary species is encouraged,particularly in game reserves, however, multiple-use plans for these reserves must understand theimportance of critical food and habitat timber species for wildlife populations, particularly for old-growth forest stands (Dudley, Mensah-Ntiamoah, and Kpelle, 1992).

The government has allegedly been promoting sustainable agro forestry programs, as well asattempting to extend the forest (Wagner and Cobbinah, 1993). All but one of Ghanas diverse andnumerous array of reserves have been established since the declaration of independence and havesurvived despite economic hardship. Attention has been drawn to the need for assistance insupporting all forms of agro forestry at the farm level, since if the trend of converting forest zonesto grassland savannah is not halted, this would lead to a disastrous situation of reduced food

production, declining soil fertility and water supply problems (Mann, 1990).In conclusion, deforestation has been the cause of a problem seen throughout Africa: aridity of landand water shortage. Population pressure is the main cause of deforestation and is a dual danger towildlife: through hunting of scarce game and through removal of habitat. While Ghana manages itsforestry reserves in a manner that should be emulated elsewhere, there is room for improvement.Continued protection of reserves and promotion of sustainable agro forestry programs andpopulation control, if possible, are necessary to achieve the proposed goal of net reforestation.


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ReferencesBowell, R.J. (1993). Mineralogy and geochemistry of tropical rain forest soils: Ashanti, Ghana.Chemical Geology, 106:345-358.

Dei, G.J.S. (1989). Hunting and gathering in a Ghanaian rain forest community. Ecology of Food

and Nutrition, 22(3):225-243.Dudley, J.P., A.Y. Mensah-Ntiamoah, D.G. Kpelle (1992). Forest elephants in a rainforestfragment: preliminary findings from a wildlife conservation project in southern Ghana.AfricanJournal of Ecology, 30(2):116-126.

Fargey, P.J. (1992). Boabeng-Fiema Monkey Sanctuaryan example of traditional conservation inGhana. Oryx26(3):151-156.

Jamieson, B. (1993). Return to Ghana.International Wildlife17:38-41.

Kurian, George T. 1992. Atlas of the Third World, 2~ ed. Facts on File Publishing Co., New York,New York. 384 pp.

Mann, R.D. (1990). Increasing aridity in Ghana/Time Running Out: the urgent need for treeplanting in Africa. The Ecologist 20(2):48-53.

Myers, N. 1992. The Primary Source. W. W. Norton ~ Company, New York, New York. 416 pp.

World Resources: a report by the World Resources Institute and International Institute forEnvironment and Development. 1990/1991. Basic Books, New York, New York. 383 pp.

Deforestation Pressures in Ghana

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