Chapter 3: SOIL AND LAND





   
 
  SOIL AND LAND

 
  3.0 Introduction

Malawi has a land area of approximately 9.4 million hectares of which 28% is in the northern region, 38% is in the central region, while the remaining 34% is in the Southern Region. Due to low mineral resources endowment, the relatively fertile land and fisheries form the basis of the country's economic infrastructure. Agriculture still dominates the economy.

There are three categories of land tenure in Malawi which help explain the scale of agricultural production: customary land, private land and public land. Customary land which forms the bulk of land in Malawi (Fig. 3.1), is held, occupied or used under customary law and excludes all public and private land. Public land is land that is used, occupied, or acquired by government and also any land that is not customary or held under freehold or leasehold title. Public land consists mainly of forest and wildlife reserves and any other public places.

The amount of land and extent of utilization in each tenure type is a matter of intense debate at present. Three land utilisation studies were commissioned recently to ascertain tenure status in Malawi. The Estate Land Utilisation Study (1997) estimated land under private estate at l. l million hectares. The Public Land Utilisation Study revealed that land under public tenure stands at 1.8 million hectares and land under customary tenure is estimated at 6.2 million hectares, according to the Customary Land Utilisation Study (BDPA, 1997).

Land provides water, food, fuel, income, grazing, building materials, fibre, space for living and recreation, and many other resources for supporting life. Various pressures exerted on land due to increasing population densities and bad land use practices cause several forms of land degradation. Soil erosion ranks as the most serious environmental problem in Malawi (DREA, 1994).

The population density in Malawi is considerably high and the national average density was approximately 87 people per square kilometer and 171 people per square kilometer of arable land during the 1987 Census (NSO, 1987). The Southern Region has the highest population density ranging between 230 and 460 people per square kilometer of arable land, varying from district to district (see Table 4.2, Chapter 4). With such high densities land holding sizes are too small to meet people's needs.

Further, intergenerational fragmentation of land holdings continue to rise to levels where, at present dominant traditional management levels, land parcels cannot produce enough food for households. Cultivation has, therefore, encroached into environmentally fragile areas like steep slopes, dambos and stream banks often with no conservation measures.
 
 
  3.1 Pressure indicators

3.1.1 High population growth rate

The high population growth has translated to rapid increasing demands from land in terms of food, shelter, energy (fuel-wood) and construction materials. While land available for agricultural production is limited to only 32% of the land area for rain-fed cultivation at traditional management level, as much as 48% of the land was found to be under cultivation by 1989/90 (Green and Nanthambwe, 1992). This meant that 16% of cultivation was taking place in marginal and unsuitable areas.

This was determined by land use studies conducted using satellite imagery and aerial photographs in the periods 1965/67, 1971-76, 1989/90 and 1995 (see Map 3.1). It was realised that land under agriculture increased from 2,064,600 ha in 1965/67 to 3,026,400 ha in 1971/76 and to 4,540,000 ha in 1989/90. Obviously, this figure has risen by now.

3.1.2 Loss of biomass energy sources for agricultural production activities.

Besides wood harvesting for fuelwood, land clearing for agriculture is one of the main contributors of deforestation in Malawi. Tobacco curing is another cause of deforestation and the estate sector alone consumes an estimated 84,826 m3 of wood for tobacco curing annually (Table 3.1).

Since the liberalisation of tobacco in 1994, the number of farmers growing tobacco has increased tremendously as manifested by the number of registered burley clubs which has increased by 680% from 1,318 clubs in 1994 to 19,014 clubs in 1997 (SADP, 1997). The production of flue cured tobacco has exacerbated this situation.
 

3.1.3 Poor agricultural practices

Agricultural practices that do not promote healthy growth of crops and fast development of good ground cover to protect the soil from rainfall induced erosion include; late land preparation, late planting, poor weed control, non-use of organic or inorganic fertilizers and poor plant populations.

The majority of smallholder farmers in Malawi practice unimproved traditional methods of cultivation. Most of them apply no or minimum improved inputs, soil and water conservation technologies are not practised, and generally, the adoption rate for most land husbandry technologies is low. As a result, production is largely for subsistence. While ridging is a common practice, except in a few areas in the low lying areas of lower shire valley and the lakeshore plain, most ridges are not made on the contour as recommended. It is estimated that only about 12% of the cultivated land has ridges on contour.

Quantitative data on the effect of different land use systems on soil erosion and nutrient loss is scanty. However, a study was carried out at Bvumbwe to determine the impact of four agricultural practices on soil loss and the results are presented in Box 3.1.

3.1.4 Infrastructure development

The development of infrastructure projects like roads and buildings necessitate removal of vegetation and earth. If done without environmental impact considerations, they can cause untold environmental problems. Roads are normally aligned on crests (catchment riding lines) and require adequate drainage. The mitre drains from the roads are led to agricultural fields often at erosive grades, and these cause a lot of soil erosion and mostly result in unsightly gullies.

3.1.5 Government policy

Until recently there was no umbrella policy and legislation for environmental conservation. There is now a National Environmental Management Policy and National Environmental Act (1996) besides the numerous sectoral policies, laws and legislative rules and regulations relating to land use in Malawi, each of which deals with a particular aspect of land management.

Despite these policies and legislation, land degradation and other associated problems are continuing. This is mainly a result of policing problems due to, among other things, leek of both human and financial resources.

Liberalisation of tobacco growing has increased the pressure on land for tobacco growing and the devaluation of the local currency has led to sharp price increases for agricultural inputs, particularly fertilizers and has lowered the use of fertilizer by small holders.
 
 
 
  3.2 State indicators

3.2.1 Decreasing land holding sizes

It was noted earlier (section 3.0 and 3.1.1) that high population densities and growth rate have resulted in reduced amount of available land per farming family. In 1987/88, 56% of all smallholders in Malawi cultivated less than one hectare of land, 31 % had 1 to 2 hectares, and only 13% had more than 2 hectares (Fig.3.2).

In 1996/97 cultivated land was 0.86 ha per holding (BDPA 1997) which represents a decrease of about 22% over the last ten-year period. Land pressures are forcing smallholders to undertake continuous cropping, often of cereal mono-cultures dominated by maize (grown on 75% of total land area) without rotations or fallow (UNICEF, 1993).

3.2.2 Cultivation of marginal and unsuitable lands.

According to land resources appraisal results based on the FAO land suitability assessment methodology, under unimproved rain-fed traditional agricultural management 8% of the land area is good quality land, 24% is moderate quality land, 31% is marginal land and the remaining 37% is unsuitable land (Green and Nanthambwe, 1992).

Further agriculture growth is now expanding into the Brachystegia-Julbernadia woodlands that once dominated most of the plateau zone and the broad-leaved deciduous Combretum, Acacia and Piliostigma forests that were once common and are now replaced by agricultural crops. The broad grass-covered dambos have been either overgrazed or cultivated and are left bare without grass.

Silt loads in surface water run-off has recently led to significant problems in downstream water quality, such as increased suspended solids, biochemical pollution and water treatment costs, decreased hydroelectric power generation capacity, water flow problems and siltation of ports.

3.2.3 Declining soil fertility and yields

Most soils in Malawi are inherently low in nitrogen, which is a very important nutrient to plants. Most areas have light to medium textures and are liable to leach of nutrients to below the rooting zone under intense rainfall. Continuous cropping which does not give enough time for replenishment of soil fertility exacerbates the problem, leading to soil exhaustion, and increasing need for inputs of conservation. The use of organic matter is low as most land use practices destroy the crop residues and animal manure application is not common. Consequently crop yields are low. While use of inorganic fertiliser may be recommended, most smallholder farmers cannot afford it due to price increases resulting mainly from currency devaluation.

3.2.4 Soil erosion

Loss of topsoil is the most serious environmental problem in Malawi. The calculated impact on yields resulting from soil loss is demonstrated in Table 3.2.

Trends in soil loss for Malawi are difficult to determine as the data on soil loss is very scanty and the little data available is inconsistent.

Proximal indicators point to the conclusion that the rate of soil loss is on the increase, considering the increased sediment loads of the rivers and reservoirs. More work is needed, however, to identify the contribution to sediment loads in rivers from farms, river bank erosion, road construction and forest activities.

The common land preparation method among smallholders in Malawi is the annual construction of ridges of about 90 cm apart, a practice which involves shifting soil at the same depth annually. Under conditions of low inputs and continuous cultivation this practice creates a hard pan at shallow depth leaving the topsoil prone to erosion.
 
 
  3.3 Response indicators

3.3.1 New constitutional provision and legislation

The prevention of the degradation of the environment (including land) is enshrined under the new Constitution of Malawi adopted in 1994 and the government will ensure that measures are in place to reduce land degradation (see section 1.2.2, chapter 1).

3.3.2 Family planning policy

Recognizing the problem of rapid population growth, the government commissioned a National Family Planning Programme that has been operational since 1982. During this intervening period, many lessons have been learnt leading to the formulation of Family Planning Policy and Contraceptive Guidelines. Besides government, a number of non governmental institutions are involved in the provision of health services that include family planning, safe motherhood and primary health care.

3.3.3 Land reform policy

The Government has initiated a land reform policy debate which is being coordinated by the Presidential Commission of Enquiry on Land Policy Reform. The Commission is consulting widely with stakeholders and making recommendations for a tenure system that promotes equitable access to land, security of title to land and improved land administration. Government has also commissioned studies to look at the amount of land under different tenure systems and levels of utilisation (see section 3.0). Preliminary information from the studies concludes that there is suitable land still uncultivated.

3.3.4 Land regulations

The Land Act is the main legal provision governing land matters in Malawi. It provides both substantive and procedural law relating to the administration of land. However, the provisions in the Act pertaining to use are not strictly adhered to, mainly due to enforcement problems. This Act and other natural resources sectoral Acts are in the process of being reviewed to be brought in line with the new Environmental Management Act (see Table 1.1).

3.3.5 Community based natural resources management (CBNRM)

Several Malawian organizations are engaged in implementing activities that strengthen the capacity of communities to manage their natural resources. This is a result of the realization that communities must be empowered to conserve the environment and get benefits from this effort if they are to participate fully in conservation activities.

3.3.6 Establishment of a natural resource endowment fund 

An Endowment Fund Working Group has been established under the auspices of the NATURE programme to identify and address issues relating to the creation and operation of a fund to be part of the Environmental Fund established in the Environmental Management Act. The objective of the fund is to provide a sustainable source of financing for conservation and natural resource management. The concept reflects the uncertainty of future donor financing and the need for leveraging private sector financing resources.

3.3.7 Soil conservation technologies 

Soil conservation technologies for cultivated land has the following main objectives:

  • to keep the soil healthy and so optimize soil condition for plant growth;
  • to optimize soil moisture availability for plant growth and, 
  • to keep the soil in place so as to retain soil and nutrients for plant growth.
The technologies fall into four main categories:
  • Correct land selection
  • Physical soil conservation measures
  • Agronomic practices
  • Agro-forestry practices
Correct land selection 

Correct land selection is a function of land use planning to determine the best use of land and is essential to ensure that soil and water conservation measures will be possible with the usual practices. The general objective of land use planning is to provide the most productive and efficient use of available resources (land, water, vegetation etc.), while conserving the resources so that this production can be sustained over time. For growing arable crops land is suitable if it has:

  • gentle to moderate slopes (less than 12% slope) so that rainwater run off speed is not excessive; and
  • deep well drained soils for reasonable infiltration and to avoid waterlogging conditions.
Correct land selection is not followed, especially not in the customary sector, where marginal and unsuitable lands are being used for agriculture. There is a lot of steep slope cultivation, river bank and dambo cultivation.

Physical soil conservation measures 

These measures provide physical control layouts that help both to store a maximum amount of rainwater in the soil and to control the remaining runoff. The measures involve: 

  • reducing slope length thereby reducing runoff velocity and volume;
  • reducing slope gradient which reduces runoff velocity and transportability of the soil particles; 
  • reducing catchment area thereby reducing runoff volume; and
  • providing safe drainage for controlled runoff
Two main low-cost soil conservation technologies are in use as first line of defense against soil erosion in Malawi are:

Contour ridges with the exception of some parts of the lower shire and the lakeshore, ridging is often used as first line of defense against soil erosion. The emphasis has been to ridge on the contour by using the A-Frame and the Line Level in pegging marker ridges. However, despite intensive campaigns by the Ministry of Agriculture and Irrigation through extension, only about 12% of the cultivated land can be said to have true ridges on the contour.

Box ridges or tied ridges are made across the furrows from one crop ridge to the next and slightly lower than (2/3 the height of) the main crop ridges. Spaced at approximately every 2 meters and staggered from one furrow to the next, box ridges help crop ridges hold back and infiltrates more water into the soil. This brings two main types of benefits: water conservation (harvesting) in dry areas and control of runoff and erosion particularly around depressions, anthills and other problem areas where crop ridges are not very close to the contour.

Agronomic practices

These are crop husbandry practices that emphasize conservation benefits aimed at the control of rain-splash and improvement of soil health. These include physical, chemical and biological measures such as cover crop management, contour farming, minimum tillage, early ploughing, good crop husbandry, crop rotation, fallow and crop residue management.

Agroforestry practices

Under agroforestry practices, trees, shrubs and grasses are grown in and around fields in various ways to provide overall resource benefits. Besides providing benefits such as woodfuel, poles and fodder, agroforestry technologies improve soil fertility and help reduce soil erosion. The Ministry of Agriculture and Irrigation (MOAI) is promoting Agroforestry technologies through a number of projects. A number of technologies have been packaged by the MOAI into an agroforestry Field Manual for extension staff.

Vetiver grass hedge 

Vetiver grass is planted on contour lines or contour marker ridges to form a thin but dense hedge line. This controls runoff and improves moisture retention mainly through accurately marking the contour to guide crop ridges, slowing down and dispersing concentrated flows of runoff water. Vetiver is very hardy and resistant to drought, rough grazing and fire. It has a very dense root system that completely binds the soil, and the hedge is dense and strong so that runoff water only passes slowly through it. Its seeds are sterile hence unwanted spreading of weeds does not occur. Vetiver grass is therefore the best vegetative contour hedge for control of erosion but it can also be used for thatching or mulching (e.g. in tobacco nurseries). 

The demand for this technology outstrips the limited supply of planting materials. To address these problems, MOAI has established a number of Vetiver nurseries in all ADD's.

Napier grass hedge

Napier grass is planted in a similar manner to vetiver but is generally less effective in controlling runoff. Napier grass is a very nutritious and palatable fodder and as a result, it is susceptible to rough grazing. It is also susceptible to fire and drought, but it can be useful as part of contour strip cropping and for stall feeding livestock. 

Contour shrub hedgerow 

A number of shrubby trees are planted at close spacing along the contour lines or marker ridges to mark the contour lines and provide fodder, stakes (mikangala), fuelwood and mulching material. 

Cassia spectabilis: Termite resistant, fairly drought tolerant, not grazed, and good for soil fertility. 

Gliricidia septum: Termite resistant, drought tolerant, generally not grazed although it can be used for fodder if dried and is good for soil fertility. 

Leucaena leucocephala (Lukina): Susceptible to termites and grazed, but drought resistant, good for soil fertility and provision of fodder. 

Cajanus cajan (Pigeon pea): Moderately susceptible to termites but provides food and mulching material for soil fertility improvement. 

3.3.8 Soil fertility improvement technologies

Early ploughing

Early ploughing, done very soon after harvest (March or April) while the soil is still moist has these advantages:

  • Allows incorporation and decomposition of trash and crop residues which improves the organic matter status of the soil and reduces the fertiliser requirement of the next crop.

  •  
  • Removes transpiring plants/weeds and leaves a broken soil layer which helps conserve the moisture in the soil for the next crop. 
Crop rotation

Crop rotation is a fundamental requirement of e cropping system. Because different crops have different characteristics, a number of benefits can accrue from growing crops in rotation. However, the prevalence of small land holdings precludes the practicing of crop rotation in the customary sector.

Khola manure

In areas where there are sufficient livestock, the manure from the kraal or khola is one of the best sources of organic fertiliser. To reduce the risk of introducing weed seeds or pests application of well-decomposed manure from kholas is recommended. The manure may be applied at each planting station in an established stand.

The organic material helps bind the soil particles together to improve structure, and also improve the ability of the soil to hold nutrients (e.g. from chemical fertilizers).

Crop residue management

Unless it has to be destroyed to prevent some disease or pest problem (as with tobacco or cotton), the crop residue remaining after harvest is a very valuable resource:

  • as a source of organic material for incorporation into the soil for maintenance of soil fertility and structure, but also assist in soil erosion control and water conservation;

  •  
  • as fodder for livestock.
A common practice is to incorporate such crop residues through early ploughing, to allow decomposition to release organic matter, which improves soil structure and fertility. However, it is noted that improperly managed crop wastes can reduce plant growth in the following season. 

Chapter Reference:
 


 
 Contents | Foreword  | Acknowlegdements | Editorial Process
Contributors | Preface | Acronyms  | Overview
Chapters: | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | Appendix I
Lists: Maps | Figures | Tables | Boxes | References