Sierra Leone

Sierra Leone > countries > home

This report was prepared by
Prof/Head Edward Rhodes
Depart. of Soil Science, Njala University, Sierra Leone

last updated: 29 July 2004

News :

Country overview
Land resources
Water resources (AQUASTAT)
Plant nutrient resources
Hot spots
Bright spots
Challenges and viewpoints
References / Related internet links

1.   Country overview

1.1  Geography and administrative units

1.2  Socio-economic features

1.3  Climate

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1.1  Geography and administrative units


Sierra Leone lies between 6 55' N and 10 00'N and longitude 10 16'w and 130 18'N. It is bounded on the west by the Atlantic ocean, on the north by Guinea and the south-east by Liberia.

[Map 1.1.1: Outline Map]

[Link 1.1.1: Siera Leone geographical map]

Administrative Units

[Table 1.1.1: Administrative Units]

1.1 > 1.

1.2  Socio-economic features

1.2.1 Population
1.2.2 Economy
1.2.3 The Role of Agriculture in the Country’s Economy
1.2.4 Major food and cash crops
1.2.5 Cropping intensity

1.2.1 Population

The population in 1998 was estimated to be 4.6 million with a growth rate of 2.6 per cent.

1.2.2 Economy

The main economic sectors are agriculture (crop production, fishing, animal, husbandry, forestry); industry (mining and quarrying, manufacturing, handicrafts, construction); services (trade and tourism, hotels, transport, storage, communication, finance, insurance, real estate).

1.2.3 The Role of Agriculture in the Country’s Economy

Prior to the escalation of the rebel war, the agricultural sector (including forestry) accounted for 33% GDP. During the war (1990/1991 and 1998) the sector accounted for 43 to 49% of GDP, with the crops subsector accounting for 31 - 36%. The GDP between 1997 and 1999 was about $ 300 million to $ 350 million.

1.2.4 Major food and cash crops

The major annual crops of importance both in area and production are cereals ( rice, guinea corn, bulrush, millet, fundi); tubers (cassava, sweet potato, yam); oil seeds (groundnut, benniseed); grain legumes (pigeon pea, bean, cowpea ) and vegetables. Others are tobacco, cotton and pepper.

The perennial crops are oil palm, cacao, coffee, kola nut, citrus, mango, rubber, cashew, sugar cane, ginger and raffia palm.

The annual crops are mainly food crops with rice being the number one staple; tobacco and cotton are cash crops. The perennial crops are mainly used as cash crops with oil palm, cacao and coffee being the most important.

Rice production has not kept pace with demand.

FAO estimates that paddy production declined from 630,000 t in 1977/1978 to 430,000 t in 1989/90 (before the rebel war). According to the Ministry of Agriculture, Forestry and the Environment, production in the 1996 was 256,000 t with an estimated demand of 478,000 t.

Cassava production, according to estimates of the Central Statistics Office, rose from 113,000 t in 1986/87 to 123,000 t in 1990/91 while sweet potato increased from 14,000 t to 15,000 t over the same period.

More recent data on crop production is unavailable because of the rebel war. Despite the signing of a peace accord in July 1999 agricultural activities have not been normalized.

1.2 > 1.

1.3  Climate

Sierra Leone is in the lowland humid tropics. It experiences a marked rainy and dry season, with the changing position of the inter tropical convergence zone (ITCZ) being the dominant influence. The discontinuity line between the different air masses shifting seasonally north and south, causes the invasion of northerly dry winds from the Sahara desert (harmattan) in January and the southerly wetmon soon winds in July. There is a dry season (December to March) and premonsoon (April to June), monsoon (July to September) and post-monsoon (October to November).

Rainfall varies between 2000 mm in the north to 4000 mm in the south. Intensity of rainfall can be very high. A maximum daily rainfall of 297 mm in Bonthe and a maximum hourly rainfall of 150 mm in Freetown have been recorded.

[Map 1.3.1: Distribution of Mean Annual Rainfall]

Average rainfall far exceeds evapotranspiration; in the south and east there is an excess of precipitation over evapotranspiration for 8 months; in the north the period drops to 7 months. The minimum length of the growing season in Sierra Leone is about 250 days.

Average temperatures are between 24.6C and 28.3C. There are diurnal and seasonal variations of temperature. Maximum temperatures occur in March and April and minimum in July and August (mean monthly maximum of 27C to 28C ). Mean monthly minimum temperatures in December, January and February are 14C to 20C. During the remainder of the year minimum temperatures vary little from 20 C to 23C.

Sunshine varies substantially with the amount of cloudiness averaging 6-8 hrs per day during the rainy period.

Relative humidity is usually very high (95 -100%) especially during the rainy season. It drops to 20% during the harmattan.

1.3 > 1.

2.   Land resources

2.1  Physiography

2.2  Soils

2.3  Agroecological systems

2.4  Wetlands, mangroves and inland valley bottoms

2.5  Inundation Land Types

2.6  Natural hazards

2.7  Land cover

2.8  Land use

2.9  Land use change

2.10  Land Productivity

2.11  Environmental Impact of land uses

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2.1  Physiography

There are four broad physiographic regions: coastal plains, most of which is less than 15m above sea level; interior plains which rises from an elevation of about 15m in the west to about 200m in the east; plateaux in the north-east and south-east with some areas as low as 150m but which in general rises from 300 m to 700m in elevation; hills and mountains with peaks higher than 1800m. The acreages of the regions and sub regions are shown in table 2.1.1.

[Table 2.1.1: Physiographic regions and subregions]

[Map 2.1.1: Main physical regions]

2.1 > 2.

2.2  Soils

The soils of Sierra Leone are ferralitic; they have been grouped in to 12 soil associations (Table 2) on the basis of soil attributes that are important for land suitability and can be easily measured.

[Map 2.2.1: Soil associations]

[Table 2.2.1: Soil associations]

[Link 2.2.1: Directory of Soil Institutions and Experts in Africa]

2.2 > 2.

2.3  Agroecological systems

Land suitability for major crops types

[Table 2.3.1: Suitability class and areas of selected crops]

2.3 > 2.

2.4  Wetlands, mangroves and inland valley bottoms

(information currently not available)

2.4 > 2.

2.5  Inundation Land Types

(information currently not available)

2.5 > 2.

2.6  Natural hazards

(information currently not available)

2.6 > 2.

2.7  Land cover

Refer to 2.8 Land use.

2.7 > 2.

2.8  Land use

Twenty land use types have been identified and are shown in Table 2.8.1.

[Table 2.8.1: Land use types]

[Map 2.8.1: Vegetation and land use]

[Table 2.8.2: Land type and size]

2.8 > 2.

2.9  Land use change

(information currently not available)

2.9 > 2.

2.10  Land Productivity

(information currently not available)

2.10 > 2.

2.11  Environmental Impact of land uses

(information currently not available)

2.11 > 2.

3.   Water Resources (AQUASTAT)

3.1  Hydrography

3.2  Irrigation and drainage

3. > top

3.1  Hydrography

[Link 3.1.1: AQUASTAT Country profile of Sierra Leone]

3.1 > 3.

3.2  Irrigation and drainage

[Map 3.2.1: Drainage and river basins]

3.2 > 3.

4.   Plant nutrient resources

4.1  Plant nutrient use and nutrient balance

4.2  Fertilizer production and costs

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4.1  Plant nutrient use and nutrient balance

[Table 4.1.1: Nutrient budgets in Siera Leone]

4.1 > 4.

4.2  Fertilizer production and costs

Use of chemical fertilizers

[Table 4.2.1: Fertilizer Consumption]

The chemical fertilizers commonly used in Sierra Leone are Urea and compound NPK's such as 15:15:15 and 20:20:0.

Mineral fertilizers are expensive and other options of soil fertility management are therefore being investigated. One such option is hedgerow intercropping (alley cropping) of fast growing leguminous shrubs with food crops. Among the shrubs investigated Gliricidia sepium is among the most promising; its foliage is a good source of nitrogen, and the woodier parts can serve as fuel wood (Table 7 and 8).

[Table 4.2.2: Effects of between row & within row spacing on leaf nitrogen yields of Gliricidia sepium]

[Table 4.2.3: Potential fuel wood production of Gliricidia sepium on land alley cropped with maize]

Fertilizer subsidies

Subsidy reduction commenced in 1993 (60% remora) and was completely removed by 1996. Up to 1999 fertilizers were sold by government at cost recovery prices.

Farm budgets

[Table 4.2.4: Farm budgets - Upland rice]

  1. It has been estimated that the upland cropping system normally consists of more than fifteen different crops. This affords a better spread of cash flow. It is also a pragmatic risk aversion strategy. It also affords the farmer a better chance to vary his crop density in relation to labour constraints and market opportunities. It is assu med that rice, cassava and other crops(millet, sorghum, benniseed) occupy 0.7, 0.2 and 0.1 of space respectively.
  2. These consist of millet; sorghum; benniseed; maize; etc.
  3. The cost of hired labour varies considerably. It varies between Le.150/MD to Le.500/MD. This consists of cash payments, food beverages, kolanut, etc. A Le.250 per MD is assumed.
  4. Only rice and cassava are improved cultivars. Local cultivars are assumed for the other crops but they benefit marginally from fertilizer use.
  5. At the rate of one bag (50kg) of 20-20-0/acre.
  6. Farm tools consist of two hoes, two cutlasses and two harvesting knives depreciated over three years.
  7. Farmers are assumed to receive loans for fertilizers, improved cultivars, hired labour and farm tools at interest rate of 30%.
  8. The low returns/MD as will be observed for almost all of the major crops are the result of low productivity and lower prices of produce.

[Table 4.2.5: Farm budgets - Inland Swamp rice (one acre)]

  1. Farmgate price of paddy is Le.2500/bushel.
  2. 20% of required labour under traditional and 70% of required labour for development and 20% of required seasonal labour under developed.
  3. Cost of improved rice is Le.4000/bushel and that of traditional varieties is Le.3000/bushel.
  4. Fertilizer application is 50kgs of 0-20-20 and 50kgs of Urea acre.
  5. Consist of two sickles, two swamp hoes, one spade, two shovels, one mattock, two cutlasses and two head pans depreciated over three years.
  6. Interest at the rate of 30%.
  7. If the development cost of the swamp is amortized the negative returns for year one will be reduced but the returns for years 2;3 etc. will be lower. Return/MD is lower because the use of swamps is not normally optimized. The notion behind the use of swamps is to double crop - rice followed by rice and/or other high value crops and legumes. This practice has not been adopted on a sustained and sustainable basis. This is one of the major reasons for low returns/MD for developed swamps.

4.2 > 4.

5.   Hot spots

5.0  Overview: constraints to sustainable agriculture

5.1  Land-related constraints

5.2  Water-related constraints

5.3  Plant nutrition-related constraints

5.4  other constraints

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5.0  Overview: constraints to sustainable agriculture

Prognosis of environmental problems

Within the Sierra Leone context, the most significant problems hampering the cohesive, systematic, and effective protection of the environment embody the following box:

Box : Diagnosis of the main Environmental Problems in Sierra Leone

  1. Weak Institutional Framework and lack of Logistical Support
  2. Land Degradation and deforestation
  3. Pest Infestation
  4. Urban Degeneration due to poor Housing Facilities, Poor coverage of Water and Sanitation as Well as Waste Management for the Poor
  5. Loss of Biodiversity, and
  6. Pollution

Source : 2004 Report Summary Of The Environmenmt Sector Review

5.0 > 5.

5.1  Land-related constraints

Land Degradation and deforestation

The natural environment in Sierra Leone may be divided in six broad ecological zones based on geology, pedology, vegetation, physiography and fauna: They include the following: Forest in regrowth, Primary forest (Tropical Rain Forest), Savanna grass land, Boliland, Riverine grass land, Inland valley swamp, Mangrove swamps and Aquatic ecologies. Each of these ecological zones comprises distinct features including physical and biological characteristics. Each constitutes a distinct ecosystem.

The poor have to clear forests to conduct their farming activities as well as harvest forest and other land resources for their livelihood. Subsistence farming is the main culprit of widespread environmental degradation. Some of the major economic activities that lead to land degradation within the Sierra Leone context are found in following Box.

Box : Principal causes of Land Degradation

  1. Subsistence farming
  2. Deforestation (Fire wood collection, Logging, shelter construction etc.)
  3. Mining
  4. Urbanization
  5. Coastal and River erosion or Sedimentation
  6. Road Construction

Deforestation and Biodiversity loss

In 1979, the FAO supported Land Resources Survey Project published that the rain forest had shrunk to 5%. There are about 3.8 million hectares of forest regrowth, with 26,000 hectares of secondary forests (UNDP/FAO 1970). The situation is worse today.

Several factors account for deforestation. In each case vegetal cover has to be stripped to make way for man's development or economic aspirations. Some of the major development and economic activities include the following: Subsistence farming, Road construction, Fuel wood collection, Mining, Shelter construction, Logging, Charcoal burning, and Bushfires. Forests are the habitats of most of the fauna and flora in the country. As they dwindle so do the populations of living organisms. The farming system practiced in Sierra Leone is the "Slash and Burn or the Rotational method". In 1960, nearly 60% of the land area of the country was lush tropical rain forest with its full complement of biodiversity MAFFS). This has been systematically reduced to secondary forests through various life-sustaining economic activities. From recent surveys conducted (2004), an estimated 22mil. M3 (twenty two million metres cubed) of biomass is harvested every year for firewood.


Sierra Leone is endowed with several types of economic minerals. And their extraction is usually by open cast mining. This method of extraction literally converts large tracts of hitherto arable life-sustaining land into wasteland. It leaves behind pits ranging in dimension from 2m x 2m to 200m x 600m. These are soon filled with water, with the unsavory implications for vector propagated diseases. The districts where open cast has occurred or is ongoing include: Bo, Bonthe, Kenema, Kono, Moyamba, Port Loko, Pujehun, and Tonkolili, constituting nearly 60% of the land area of the country.

Roads, Erosion, Sedimentation and Urbanisation

The construction and periodic maintenance of roads and shelter necessitate the removal of vegetal cover and the exposure of land to the elements. It sets into motion a series of activities, which result in the lateritisation of otherwise arable land. First of all with the vegetation goes the humic layer, which normally supports plant life. The soil is then dissected by erosion upon exposure to runoff water. Coastal and Riverine erosion and sedimentation cause environmental catastrophes and pose problems in marine transportation. It is not uncommon that coastal settlements get swept away by tidal waves. As human populations keep increasing forests are constantly cleared to construct shelter.

Source : 2004 Report Summary Of The Environmenmt Sector Review

Problem Soils

Potential acid sulphate soils occur in the mangrove swamps, an important agro ecology for rice production in Sierra Leone. If these soils are allowed to dry pyrite is oxidized resulting in an extremely acid environment unsuitable for rice cultivation. A practical management option is to keep the soils submerged but since water in the coastal areas is saline, management options include use of salt tolerant rice varieties & delayed planting until rains have washed out the salt from the soil.

Human induced soil Degradation

Because of breakdown of the bush fallow system due to population pressure on the land, soils are not adequately rested and their fertility is declining. Small scale farmers especially those farming the uplands, extract more nutrients from the soil than they put in (nutrient mining).

Soil erosion caused by water

Soil erosion by water is a major constraint to sustainable crop production. Soil loss by erosion in a catchment in Sierra Leone (mean annual rainfall of 2380mm) is shown in Table 9.

[Table 5.1.1: Soil loss by Erosion in the Makoni catchment]

5.1 > 5.

5.2  Water-related constraints

(information currently not available)

5.2 > 5.

5.3  Plant Nutrition-related constraints

(information currently not available)

5.3 > 5.

5.4  Other constraints

A large number of Sierra Leoneans has been internally displaced as a consequence of the 10 year civil war and cities have become over-populated by these displaced people. Urban agriculture has emerged as a strategy for coping with food needs, but it poses a serious problem to the environment if unregulated.

Pest Infestation

agricultural yield is pest infestation. The pests range in size from a buffalo to grass hopper. They invariably destroy infrastructure and crops during and before harvest.

Urban Degradation and Pollution

The poor in urban areas tend to be concentrated in congested areas or marginal landscapes such as steep hillslopes or depressed river valleys. Their shelter normally comprise of rickety structures constructed from bush sticks, mud walls and corrugated iron or plastic roofing sheets. In the face of strong gusts and rain storms these structures are readily swept away. They lack access to vital services such as water and sanitation, road network, electricity, educational and health facilities as well as municipal waste collection services. These communities have to literally coexist with their own excrement. The urban poor often have to use local streams for the multiple purposes of washing, bathing, and refuse and faecal waste disposal. This is the bare face of urban poverty. All categories of waste are dumped without sotting. These include heavy toxic metals such as Lead, Mercury and, asbestos as well as pathogens. In the wider national context, according to a rapid survey conducted in February 2004, in the western area, at least 68% of all dwelling houses are fitted with water closets. In the rural areas, nearly 75% of the households lack access to flush toilets (WC) and/or latrines. . According to MICS (2000) up to 54% of Sierra Leoneans have access to potable water of safe drinking water. This refers to water from protected wells, piped, spring or main sources thus nearly 46% of the population still depend for drinking water, on streams, ponds and unprotected springs, wells, and swamps. Some 74% of urban dwellers have access to safe drinking water while only 46% of rural people use safe water (UNICEF 2000).

Source : 2004 Report Summary Of The Environmenmt Sector Review

5.4 > 5.

6.   Bright spots

6.0  Overview: society's response to ameliorate the situation

6.1  Land-related response indicators

6.2  Water-related response indicators

6.3  Plant nutrition-related response indicators

6.4  Other response indicators

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6.0  Overview: society's response to ameliorate the situation

(information currently not available)

6.0 > 6.

6.1  Land-related response indicators

(information currently not available)

6.1 > 6.

6.2  Water-related response indicators

(information currently not available)

6.2 > 6.

6.3  Plant Nutrition-related response indicators

(information currently not available)

6.3 > 6.

6.4  Other response indicators

(information currently not available)

6.4 > 6.

7.   Challenges and viewpoints

The policy objectives of the Ministry of Agriculture (GOSL 1998) are to:

  1. Achieve national food self sufficiency
  2. Increase agricultural productivity and output
  3. Reduce the balance of payment deficit by improving the quantity & quality of cash crops for export
  4. Protect and conserve the environments biodiversity and the natural resource base for agriculture.

The strategies for attaining these objectives with respect to the crops sector and conservation of the resource base are as follows:

Land & Forest Conservation and Pest Control

Strategy: In order to achieve these goals the following strategies must be adopted:

Conservation & Protection of Biodiversity

Strategy: The following activities must result in the realization of this goal:

Source : 2004 Report Summary Of The Environmenmt Sector Review

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8.   References and related internet links

8.1  References

8.2  Related internet links

8. > top

8.1  References

All the maps on this report are from:

Andrew Bomah & Franklin Bassir (2004) Report Summary Of The Environmenmt Sector Review

GOSL (1998) Presentation of the Minster of Agriculture, Forestry and Environment. State of the Nation Symposium, Freetown.

Karim (1987) Alley cropping studies in the uplands of Sierra Leone DPhil Thesis Oxford University.

LRSP (1979) Land in Sierra Leone: a reconnaissance survey and evaluation for agriculture. Technical report No. 1. UNDP/FAO, Freetown.

MAF/FAO (1992) Agricultural sector Review/Programming Mission Sierra Leone. Mission Report Vol. 2. Ministry of Agriculture, Forestry & Fisheries. Food & Agriculture Organization, Rome.

Rhodes E.R. (1999) Macroeconomics, constraints, priorities, policies, strategies and programmes in agricultural development and management of natural resources in Sierra Leone. Consultancy Report submitted to FAO in support of the ECOWAS Agricultural Strategic Plan, Freetown.

Sesay M.E. & Stocking, M (1993) Financial cost of soil erosion on small farm intercropping systems in Sierra Leone p562-567. In Haskin, P.G. & Murphy, B.M (eds) People protecting their land. Proc. 7th ISCO Conference, Intern. Soil Conservation Assoc. Sydney.

Stoorvogel J.J. & Smaling, E.M.A. (1990) Assessment of soil nutrient depletion in sub-Saharan Africa: 1983 2000. Report 28. The Winand Staring Centre, Wageningen.

8.1 > 8.

8.2  Related internet links

Sierra Leone General

annotation: The site introduces the country in a manner somewhat similar to CIA country profile website. [editor's note]

annotation: This site aims "to globally disseminate news and ideas relating to Sierra Leone". [extract from the homepage]. Extensive links to the country, Africa, and Sub-Saharan Africa. [editor's note]

Sierra Leone on the Web
annotation: The Fact File section contains information on geography, climate, business, history, government, and language. [editor's note]

8.2 > 8.


[11/04/01] on-line
[29/07/04] add link to Directory of Soil Institutions and Experts in Africa on 2.2.1
[29/07/04] chapter 5.0, 5.1, 5.4 and 7 are updated

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