434 Journal of Food, Agriculture & Environment, Vol.5 (3&4), July-October 2007

Soil use and management strategy for raising food and cash output in Rwanda

Received 25 April 2007, accepted 29 July 2007.

Abstract Rwanda is a poor country and land is scarce, with only 0.65 ha of suitable farmland per household. Literature search for identifying constraints and solutions to productive and sustainable agriculture and livestock production was carried out. The country is facing with increasing soil fertility depletion and erosion due to steep landscape, continuous cultivation and high but not well distributed rainfall. Crops adequately allocated to the 0.65 ha farmland may produce enough food for energy and protein, but not cooking oil; animal production for meeting fat requirements is already at the limit. Forest resources are insufficient to produce necessary poles, timber, fuel and other forest-related products; alternatives must be found. Strategies to raise agricultural production include soil and water conservation, fertility improvement, irrigation and drainage, high-yielding plant varieties, improved animal management, pest control and reduction of postharvest losses. Labour shortage at critical periods of agricultural operations can be reduced through appropriate mechanisation. Such improvements that are high demanding in investments may substantially raise crop and livestock production, allowing Rwanda to develop agro-industries and the commercial sector. Alternatively, preference may be given to investments in high-value exports that can pay for imports of food, fuel and other necessities.

Key words: Rwanda, Central Africa, food security, soil fertility, land management.

Venant Rutunga 1*, Bert H. Janssen 2, Stephan Mantel 1 and Marc Janssens 3 1ISRIC-World Soil Information, Wageningen University and Research Centre, PO Box 353, 6700 AJ Wageningen, The Netherlands. 2 Plant Production Systems Group, Wageningen University and Research Centre, PO Box 430, 6700 AK

Wageningen, The Netherlands. e-mail: bert.janssen@wur.nl. 3 Tropical Agriculture Unit, University of Bonn, Sechtemer Strasse 29, D-50389 Wesseling, Germany; e-mail: marc.janssens@uni-bonn.de. * e-mail: rutunga@hotmail.com or soil.isric@wur.nl

Journal of Food, Agriculture & Environment Vol.5 (3&4) : 434-441. 2007 www.world-food.net Meri-Rastilantie 3 B, FI-00980

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Introduction Rwanda is a small (26,338 km2) land-locked country, some 1600 km from the sea; latitude 2oS and longitude 30oE; surrounded by Uganda, Tanzania, Burundi and Congo-Kinshasa. Its population density increased from 99 km-2 in 1962 to 309 km-2 in 2002 1, 2. Of a total population in 2002 of 8.1 million, 83% lived in rural areas and 36% was engaged in farming, the total active population being 42%. This population pressure means that, without adequate and highly productive soil use and management, there is land degradation and shortage of food and forest products. Before the 1994 war, many studies were carried out on control of soil erosion and improvement of soil fertility. Rwandese and donor teams working for country rehabilitation continue to pay attention to these issues; all point out the high annual loss of soil, organic carbon, and crop nutrients. However, published work since 1995 scarcely refers to the early studies that provide basic information for understanding the evolution of the present challenges of food security and cash income and which, also, can help in the rehabilitation of Rwandese programs and the efficient use of resources provided by international agencies. This paper deals with scientific information published up to and including 2005. It reviews the present state of land use in Rwanda, major constraints on production and strategies to assure sufficient food and cash income; it covers climate, soils, erosion and its control, soil fertility and its improvement, crop and livestock production.

Sources Data on climate, land area and soil properties were derived from the Rwandese–Belgian Soil Map project 3, 4. Data on cash income, food crop production and productivity are from reports by the Rwanda Agricultural Science Institute (ISAR) 5, 6, the National Commission of Agriculture (CNA) 7, 8, , the Ministry of Agriculture, Livestock and Forests (MINAGRI) 9, 10, Nyabyenda 11, 12 and Nezehose 13. Livestock numbers, fodder and production have been estimated from Minagri and project reports 7, 9, 14. Data on ruminants have been converted to Tropical Livestock Units (TLU) of 250 kg live weight; conversion factors for sheep or goats, heifers or pigs, cows, and oxen, respectively, are 0.1, 0.5, 0.8 and 1.1. One TLU needs 1264 Fodder Units (FU) year-1 for maintenance and production; one FU corresponds to the nutritional value of 1 kg of barley. The content of energy, proteins and fat in animal products consumed as human food are calculated using the norms provided by Minagri 10 and Latham 15. Norms for estimating human food requirements are from FAO 10, 16 and WHO 17. Data on forest plantations and natural forest reserves are from the Ministry of Lands, Human Resettlement and Environmental Protection (Minitere) 18, Murererehe 19 and CNA 20. Nutritional needs are calculated per average household of five persons 1, 21. Food requirements are based on a norm for an active male adult under light activity (2410 kcal energy, 59 g protein and 40 g fat per day) and proportionately less for females, children and older persons (Table 1). The food requirements of an average household are equivalent to those of 3.4 adult males.

Journal of Food, Agriculture & Environment, Vol.5 (3&4), July-October 2007 435

Present Situation of Land, Agricultural Production and Labour Geography and soils: Eleven per cent (2,849 km2) of the country is occupied by lakes, rivers, marshes, towns, roads and built-up areas. The remainder (23,487 km2), called “green land”, can be used for crops, grazing, and natural vegetation. In this study, land area always refers to this second category; flooded marshes are excluded because any action there will affect downstream flows to Lake Victoria and the River Nile that are governed by international treaty. Rwanda green land is located into three altitude zones: low, <1600 m, 38%; middle, 1600-2100 m, 33%; and high, >2100 m, 18%. Mean temperature ranges from 15oC at high altitude to 25oC at low altitude. There are two rainy seasons, centred round April and November, alternating with dry seasons. From highlands to lowlands, annual rainfall ranges from more than 2000 mm to less than 1000 mm 22. Rainfall events are erratic, especially in the eastern part of the country and drought or excess of rainfall may cause yield losses from 25 to 100%. The most relevant soil parameters for crop production in Rwanda are summarised in Table 2. Major interventions are needed for the maintenance and improvement of soil productivity: drainage is required for the 5% of land; special measures for erosion control are needed on the 53% of the country that has slopes steeper than the 6o limit for agronomic erosion-control measures; soil amendments and nutrients are always needed, but especially on the 51% of soils with base saturation less than 35%; shallow soils (thickness < 0.5 m) occupy 25% of the land; soil organic matter quality and, sometimes, its quantity also govern crop production23. Land suitability for crops is assessed by Verdoodt and van Ranst4 (Table 3). However, much unsuitable land is already cropped.

Crop production: The most important food crops and their nutritional values are listed in Tables 4a and 4b. For optimum land allocation to ensure enough food to the household, crops were matched with the areas where return on agricultural inputs would be maximised 20, 24, 25 taking account of farmers’ preferences and the complementary compositions of cereals, roots, tubers and legumes in matching the energy, fat, protein and vitamin needs of the household. To meet nutritional needs, the ratio of area under legumes (Re) is maximised as1[(1+ (a-b)/(c-a)]-1, where a is the ratio of needed energy fat-1 for a male adult in a day, b the ratio of energy fat-1 in a kg legume and c is the ratio energy fat-1 of all cultivated crops except leading legume. Farm area times Re provided the maximum area for the legume (Lm). For ensuring an adequate human diet, the Lm was iteratively decreased in order to have enough area for required non-legumes. Soya and peanuts are not adapted to the highlands, hence sunflower (Helianthus annuus L.) and/or colza (Brassica napus L. var oleifera Delire) may be introduced. Apart from these rain-fed crops, some irrigated rice is grown in the lowland valleys. The area may be increased to 60 km2 and the yield increased from the present 2.7 to 7.0 Mg ha-1 27, a real but still small contribution to food requirements. Table 5 gives the nutritional value of produced food if all currently suitable land is optimally cropped. Compared with the nutritional needs per household, there would be enough energy and protein; the production of fat is at the limit of sufficiency when averaged for the whole country and a whole year but insufficient in some parts of the country and in some households. Additional protein and energy may be obtained through processing and eating of mushrooms, vegetables and fruits, and of young leaves from legumes, tuber and root crops. At present, the supply of protein and fat is insufficient because the area allocated to soya and peanuts is substantially less than the calculated optimum (data not shown). Our allocations to maximise food security allocate no land to cash crops such as flowers 28, 29, tea, sugar cane and pyrethrum. At present, these crops occupy about 44,000 ha which can be related to the 522 km2 unaccounted for in Table 3.

Livestock production: Animals provide milk, meat, eggs, hides and wool for consumption or sale, and manure; production depends on the number of animals (Table 6), the quantity and quality of feed, and the management. Table 7 presents the capacity of fodder production in the livestock area as estimated on the basis of the Rwanda Soil Map. In addition to the total production of 729 million FU under present conditions and 984 million FU under optimal allocation and improved management, feed is derived from agricultural by-products (estimated at 477 million FU at present 14).

Population Factora Equivalent male adults

Age group

Male Female Male Female From male population

From female population

0-4 and 75+ 690,036 709,813 0.3 0.24 207,011 170,355 5-14 and 65-74 1,166,375 1,225,837 0.6 0.48 699,825 5,884,011 15-49 1,840,411 2,067,022 1.0 0.80 1,840,411 1,653,618 50-64 182,626 246,433 0.8 0.64 146,101 157,717 Total population 8,128,553b 5,463,439

Table 1. Rwanda population and its equivalent number as male adults for food requirement, August 2002.

a Conversion factors for nutritional requirements in relation to male adult under light activity b Five persons form one average household

Characteristics Area

Characteristic Value, % % of total land km2

Slope class 0-13 47 11,045 14-55 30 7,013 >55 23 5,429

<20 25 5,866 Base saturation 20 – 35 27 6,224 >35 45 10,590 Not measured (Histosols) 3 807

Soil texture >60% clay 10 2,378 35-60% clay 70 16,194 20-34% clay 17 4,086 Sand and Histosols 3 829

Soil orders 26: Oxisols 10 2,433 Ultisols/Oxisols 19 4,549 Ultisols 33 7,647 Vertisols 2 559 Inceptisols 16 3,645 Entisols 17 3,847 Histosols 3 807

Table 2. Area of soils in Rwanda with some characteristics relevant for crop production4.

436 Journal of Food, Agriculture & Environment, Vol.5 (3&4), July-October 2007

Assuming that 1 TLU needs 1264 FU per year, 0.9 and 1.2 million TLU can be sustained under present and optimal conditions, respectively. For supplementary concentrates, only industrial by- products are available; the production of maize and soybeans is already insufficient for human needs. It is obvious that feed production is hardly sufficient for the present number of animals (Table 6). The quantity of animal products and of the human food derived from these is presented in Table 8. In 2002, the animal products provided 87 Mcal, 4 kg protein and 5 kg fat per household (calculations not shown). The fat supply from livestock products is just enough to make good the shortage in vegetable fat production under an optimum crop allocation but not enough if yields are poor, e.g. by failure of rains, or if less land is allocated to soybean and peanuts than indicated in Tables 4 and 5. The contribution of honey production is considerable.

Forest production: The area of land under natural vegetation, called in Rwanda “forests and natural reserves” but actually degraded is 7339 km2 in the Soil Map of Rwanda (Table 3), corresponding to 0.45 ha per household. This area had decreased to 4741 km2 in 2002 18, equivalent to 0.30 ha per household, which is only one tenth of the equivalent world-wide average of 3.0 ha 31. Wood products from agroforestry are equivalent to the production from 1649 km2 of degraded natural vegetation. Products are mainly wood, fodder, medicines, wild animal products and culturally- related advantages, mostly not yet quantified except for annual production of wood products estimated at 6,916,700 m3 or 0.85 m3 per person in 2002 19; the FAO norm is 0.91 m3 per person.

Labour: The number of active persons per household was calculated from the data of Table 1 using the following conversion factors: 1.0 for males between 15 and 50 years old, 0.8 for females between 15 and 50 and for males between 50 and 64 years old. It comes down to 2.24 human labour days (Hd) per household. The total available Hd per month of 22 working days is then 49, equivalent to 591 Hd per year if nobody from the household is sick or away from the farm. The labour required per ha for cropping operations of various crops is estimated in Table 9. Table 10 gives the required number of Hd per month for the three altitude zones, taking into account the calendar of the crop husbandry activities (data not shown). Availability of labour on the farm is insufficient when many tasks have to be accomplished in a short, critical period: agricultural operations are not evenly distributed over the year. After cropping operations, the labour available for livestock management, erosion control and other activities is roughly 257, 239 and 202 Hd in low, middle and high lands, respectively.

Constraints on Agricultural Production Climate and soils: In the lowlands, soils are relatively high in nutrients but dry spells are limiting production so irrigation or the use of plants tolerant to dry spells is essential in improving productivity. In the highlands, leaching is more intense; soils are poor in nutrients and, often, high in soluble aluminium 33, 34. The middle zone is intermediate. On steep land, runoff and soil erosion reduce productivity and the effectiveness of any added amendment or fertiliser 35, 36; where the topsoil has been eroded,

Land-use Actual Potential

% km2 ha household-1

% km2

ha

household-1

Crops 46 10,531 0.65 78 17,583 1.08 Grazing 22 5,095 0.31 16 4,273 0.26 Forests + natural reserves 32 7,339 0.45 4 1,109 0.07 Total 100 22,965* 1.44 100 22,965* 1.44

Table 3. Actual and potential “green land” use in Rwanda 4.

* Less than 23,487 km2, probably due to the area determination methods.

Fractions of 0.65 ha farm Crop

Growing days

Preferred season Season A Season B

Lowland Banana (Musa sp. L.) 425-545 A+Bb 0.20 0.20 Cassava (Manihot esculenta Grantz) 270-425 A+B 0.10 0.10 Peanuts (Arachis hypogaea L.) 90-120 A 0.30 Sorghum (Sorghum vulgare Pers.) 150-180 B 0.25 Bean (Phaseolus vulgaris L.) 90-150 A 0.20 Maize (Zea mays L.) 120-150 B 0.25 Sweet potato (Ipomea batatas (L.) Lamb) 120-150 A, B 0.20 0.20 Rice (Oryza sativa L.) 150 A, B Valley Valley Middleland Banana 425-545 A+B 0.15 0.15 Bean 90-150 A, B 0.15 Soya (Glycine max ( L.) Merr.) 120-180 A, B 0.50 0.35 Sorghum 150-180 A, B 0.15 Maize 120-150 A, B 0.15 Sweet potato 120-150 A, B 0.20 0.20 Highland Maize 240 A+B 0.25 0.25 Peas (Pisum sativum L.) 120 B 0.50 Wheat (Triticum aestivum L.) 90-120 A 0.50 Irish Potato (Solanum tuberosum L.) 120-150 A, B 0.25 0.25

Table 4a. Cropping characteristics and fractions of cropped area allocated to various crops if the crops were optimally distributed a.

a Evenly distributed during their cropping seasons, each crop will occupy 0.20, 0.125 and 0.33 of the farm area in low, middle and high altitude zones, respectively. b Season A: September-January; Season B: February-August

Journal of Food, Agriculture & Environment, Vol.5 (3&4), July-October 2007 437

Livestock: During the conversion of feed to animal products, there is a substantial loss of energy, water and nutrients. Therefore, meat and milk consumption by humans requires more land than consumption of primary crops and, in the Rwandan situation, replacing arable by pasture jeopardizes food security. Production of feed was hardly enough in 1986-2002 and complete conversion of erosion-prone soils and wetland to arable will decrease the area

manure and fertiliser are less effective because the subsoil usually has lower available water capacity and added nutrients are less well retained. Steep slopes dominate the middle and high altitude zones, both receiving high rainfall. Other soil limitations to crop production are related to low cation exchange capacity, moisture deficit in the lowlands, wetlands, and physical constraints in Vertisols and Andisols that occupy about 39% of the land area. According to Verdoodt and Van Ranst 4, 20% of present agricultural land is only marginally suitable for cropping under low external inputs. However, with terracing and application of fertilisers, still 3% will remain marginally suitable; even presently non-agricultural land can be reduced from 32 to 4% in the favour of land suitable to crops and pastures (Table 3). Without investment in land and agriculture improvement, soil erosion and soil fertility decline will continue, bringing lower agricultural productivity, lower food security and lower cash income 37, 38.

Crop and land management constraints: High production requires fertile land, adequate land preparation, good seeds or planting material, timely sowing and planting, control of pests and diseases, and harvesting 39, 40. In Rwanda, the quantity of biomass available as manure and soil amendment is declining due to low biomass production and to the use of biomass as fuel 36. For land preparation, enough labour and good tools are not available, and farmers often have limited access to seeds and planting material of high quality11. The yields of crop varieties screened by the Rwanda Agricultural Science Institute 6 are two to three times the average yield recorded by FAO 12 for Rwanda. The gap is related to field management and plant protection against pests and diseases - constraints include insufficient supplies of agrochemicals, lack of equipment and few qualified staff 32. Harvest and storage of products are sometimes disturbed by excess rainfall, especially in the highlands and, because of the chronic shortages of food, there is always a risk of theft from the field. If all crop production constraints were eliminated through appropriate policy measures and investments, yields of most crops could be two or three times as high as now. With optimum land allocation, energy and protein would be enough for a household using only 0.65 ha of actual suitable land although fat would still be short unless peanuts and soya were intensified in the low and middle lands and oil crops (sunflower, colza) were introduced in the highlands.

Producta Yield Mg ha-1

Energy kcal kg-1

Protein g kg-1

Fat g kg-1

Banana, fruits 4.65 338 3.4 0.6

Cassava, roots 3.95 1023 5.2 1.5

Peanuts, seeds 0.70 2780 117.5 226.8

Sorghum, grains 1.20 3038 71.5 32.0

Beans, seeds 0.80 3031 195.8 13.5

Maize, grains 0.80 (0.40)b 3225 84.9 37.9 S. potato, tubers 7.00 1081 14.3 1.8

Soya, seeds 0.60 3670 310.7 144.7

Peas, seeds 0.51 3221 205.3 10.1

Wheat, grains 0.80 2688 93.4 14.7

Potato, tubers 8.20 574 11.9 0.7 b

Table 4b. Crop yield 12 and nutritive values of harvested products 10.

Dry seeds, grains and roots; fresh fruits and tubers. b 0.80 is the yield in the low and middle lands and 0.40 that in the highlands. a

Zone Energy, Mcal Protein, kg Fat, kg

Low 4607 93 47

Middle 4334 163 60

High 3183 102 12

Weighteda average farm for Rwanda 4218 120 44

Need year-1 for an average household 2964 74 48 c

Table 5. Food production year-1 in relation to improved crop allocation on current suitable land (0.65 ha) per household, crop nutritive values and current yield of Tables 4.

c Farms are weighted to the land area in the three altitudinal zones.

Product Quantity (Mg) Nutritive value contenta

1988 2002b

Energy, kcal kg-1

Protein, g kg-1

Fat, g kg-1

Beef, carcass 7,401 10,266 2,370 149 177

Cow milk, fresh 40,694 56,449 790 36 52

Goats, carcass 10,606 7,322 1,640 162 102

Mutton, carcass 2,668 1,464 2,650 162 102

Pork, carcass 6,858 5,724 4,100 117 400

Poultry, meat 2,432 2,482 1,400 156 70

Eggs 3,587 3,661 1,400 107 102

Rabbit, meat 442 647 1,130 182 60

Honey c 7,455 3,112 3 0

Fresh fish c 1,000 970 162 31

Table 8. Rwanda food derived from animals in 1988 and 2002 and their nutritive valuesa.

a Minagri 10; Latham 15; b Extrapolated from data in 1988; c Set at same value as in 1984 data

Area Yield per haa National production (x 106)b

Land use km2 FUn FUi FUn FUi

Grazing area 5,095 561 1,214 254.8 509.5 Live hedgerowsb (480)b 3,000 6,000 148.0 288.0 Forests + natural reservesc 7,339 678 741 152.3 186.5 Total 12,434 729.0 984.0

Table 7. Rwanda estimated livestock-reserved area and production of Fodder Units (FU) under natural (FUn) and improved conditions (FUi).

a Data by Minagri 9; b Area from erosion-control structures, not reported on the Rwanda Soil Map; c Grazing under planted trees and natural reserves

Table 6. Numbers (x 103) of various animals and equivalent Tropical Livestock Units (TLU).

Animal number Equivalent TLU

Species 1988 2002 2002

Bovines 716 992 828

Goats 1 841 1 271 141

Sheep 678 372 41

Pigs 254 212 106

Total TLUa 1116

a Rabbits, poultry and bees not included. Source: Minagri-SESA 30 and Minitere 18

438 Journal of Food, Agriculture & Environment, Vol.5 (3&4), July-October 2007

of pasture to 16%: more efficient animal production is required. The incomes from various livestock were compared by Minagri : Ankole/Jersey cross-bred cows produced more milk than improved Ankole cows and the net profit with improved Ankole cows was negative if labour costs were taken into account (Table 11); the unimproved Ankole has too a low productivity to be considered. Net income is not the only criterion: in terms of protein conversion, the production of fish is more efficient than cows - fish production increases the cash income, as was shown in a small-scale fish farming programme carried out in Rwanda in 1984-1994 - but it is still less efficient than the production of food crops .

Natural vegetation and planted trees: Details on the development and limitations of the woody and herbaceous resources sector are given by CNA and Murererehe 19. The potential remaining 0.07 ha of these resources per household (Table 3) are not sufficient for forest products, although some compensation may be provided by multipurpose trees and shrubs planted within permanent cropland, on hedgerows and bench slopes. Hence, Rwanda must find alternatives for forest products and related cultural and environmental services.

Labour: Labour is in short at the start of growing seasons, and when erosion control and cropping activities clash. Production of low-labour-demanding crops (e.g., cinchona, forest trees) is not an alternative because it would jeopardize food production. Theoretically, mechanisation of agricultural operations is an option to solve the labour problems; at present, there is hardly any mechanisation and there is little information about its development in Rwanda - apart from the cost, options for mechanisation are limited by the small size and steep slopes of most farms.

Options for Improvement of Agricultural Production Soils and fertilisers: Measures for control of erosion relevant to Rwanda are detailed in WOCAT 43, 44, 45. Ridges, trenches, terraces, manuring, mulching and hedgerows may be matched with many soils of the country. Addition of organic manure and compost would improve the physical properties and the chemical properties of soils with low CEC and pH, but it is easier to recommend the use of organic matter than to implement the advice when organic residues are scarce and needed as livestock feed or as fuel. Therefore, inorganic fertilisers are indispensable. The Quantitative Evaluation of Fertility in Tropical Soils (QUEFTS) model 46 predicts the fertiliser response of food crops as a function of soil pH, organic matter and available P and K in the 0-20 cm topsoil. Table 12 gives an example for target maize yields of 4 Mg per ha on soils with representative chemical soil characteristics. With maize, the prediction on very acid soils is not valid unless mineral and organic amendments are applied to eliminate excess of aluminium, iron and manganese. Yields on other soils are mostly limited by nutrient imbalance. Low prices for crops will restrict farmers to low investment in fertilisers, low crop yields and low income. Low-nutrient demanding plants (tea, cinchona, forest trees) are an option if their produce can be exported to pay for food imports. Other causes of low efficiency of fertiliser application are soil water deficiency or excess. Although Rwanda has generally high rainfall, dry spells cause soil water deficiency and techniques to reduce evaporation, such as mulching and supplementary

9

41

42

20

irrigation, are needed, especially in the eastern part of the country. Possibilities for supplementary and small-scale irrigation are high but constrained by lack of investment.

Crop production: High-yielding crop varieties and tree species are needed. Their introduction requires screening and development of optimum management. Investment in crop protection against pests and diseases and improvement of harvest, storage and marketing techniques should be a priority. All this requires effective agricultural research and extension services, intensified and adequate use of various inputs, and establishment of improved infrastructure for storage of harvested products.

Livestock: Optimal livestock management includes introduction of high-performing breeds, protection against pests and diseases, adequate nutrition and harvest of fodder crops, appropriate housing and adequate handling of animal products 14. Fish production and harvesting techniques in lakes and rivers may, also, be improved, but there are competing claims on water resources and a risk of pollution from farming activities.

Natural vegetation and planted trees: The limited natural habitat resource is already degraded and should be protected through better management and, so, higher production from the farmlands. Agro-silvo-pastoral activities in areas of natural vegetation should be monitored and controlled. Relevant details for conservation and management are given in Masozera and Alavalapati 49, Murererehe 19 and Weber 50.

Labour: Mechanisation would enable farmers to accomplish their tasks in a timely fashion. Light mechanisation and improved hand tools seem most appropriate for Rwanda where farmers are poor and poorly trained, and land is steep. Beshada 51, Pawlak et al. 52 and ASAE Standards 53 provide useful information on how, when, and where mechanisation can improve the farming system.

General: All actions needed to achieve the Millennium Development Goals to eradicate extreme poverty and hunger, strengthen education opportunities, improve people health, ensure environmental sustainability and develop a global partnership for development - apply to Rwanda. Control of erosion is the first step to protect the productive capacity of the land 44 but it is not sufficient; the other biophysical and biotic factors influencing crop production must be optimal, which is not always the case in Rwanda. It is essential to apply fertilisers at rates tailored to soil nutrient supply and crop needs, especially in the high and middle lands 33, 54. Several authors stress the importance of combining mineral fertilisers with organic matter for improving soil quality and crop yields 55, 56. Additional strategies might include the screening of crops/varieties tolerant to acid soils 57, 58. Rwanda may triple its current animal production and improve milk quality by optimal livestock management 59, 60. This would satisfy the needs for fat and some vitamins and minerals as well as providing manure 61 and as a factor for erosion control and reduction of soil organic matter loss 44. As cropping and livestock conditions are improved, Rwanda would be able to initiate food processing, storage and distribution industries. Agriculture may then become commercial 20. There are alternatives to the insufficient supply of forest

Journal of Food, Agriculture & Environment, Vol.5 (3&4), July-October 2007 439

products, especially of fuel wood, but these require adequate policy and significant investment. Oil imports will always be costly for Rwanda, situated at 1600 km from the sea without railway or pipeline connections. Other options are production of biogas from animal and human excrements, large-scale exploitation of methane from the Kivu lake, exploitation of small waterfalls found all over the country, and of solar and wind energy. More efficient methods for cooking and improved tools could significantly reduce energy needs. All the suggested improvements, however, require financial investments but will not ensure enough food if the population continues to increase as in previous years and remains predominantly in subsistence farming 62, 63. As long as food production is insufficient, there will be no sustainable commercial agriculture; import is only feasible if it is counterbalanced by export which requires exportable commodities, national infrastructure and

markets. Werwimp 64 showed that the 1989-bean crop failure in southern Rwanda made the trading strategy of ‘banana beer for beans’ non-viable, as beans were not available.

Conclusions Rwanda is facing critical land scarcity and ecological and human catastrophe unless better soil use and management strategy and technologies are developed and adopted. Arrest of soil erosion is an essential first step but not, in itself, enough. Application of appropriate fertilisers is equally essential. Rwanda may at least triple its current animal production and improve milk quality, using high-producing breeds, good quality fodder and optimum livestock handling. Once cropping and livestock conditions have improved such that Rwanda produces sufficient food, the country will be able to initiate food processing, storage and distribution industries.

Table 9. Labour (Hd) estimation for agricultural operations of major crops on 1-ha landa.

Crop Establishment Land preparation

Planting/ sowing

Fertiliser application

Weeding Watching Pesticide application

Harvesting Pruning Total

Banana 148 31 91 61 331

Cassava 100 67 33 200

Peanut 100 65 10 50 50 275

Bean 100 57 9 48 100 314

Soya 100 63 13 50 50 275

Peas 75 31 106

Sorghum 52 62 62 171 347

Maize 100 56 25 50 50 281

Wheat 100 34 28 75 6 50 294

S. potato 215 31 246

I. potato 88 75 75 175 25 119 556 7 24 32

a adapted and modified from CNA 7; Ndindabahizi & Ngwabije 24; ICRA-ROPARWA-ISAR 32

Zone Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Total

Lowlands 68b 51 16 0 43 33 34 12 0 20 30 8 334

Middlelands 52 b 50 19 0 29 61 49 19 0 20 30 8 352

Highlands 72 35 39 15 46 41 48 11 8 41 33 0 389 b

Table 10. Labour requirements (Hd)a during the year for crop husbandry on farms with 0.65 ha of cropped area. Crop allocation as in Table 4a.

Hd: human labour during 8-hours; b Banana crop is established once, labour is not included. a

Table 11. Estimation of annual income from livestock per household.

Price ($)a Ankole/Jersey cross-bredb Improved Ankoleb Battery beef c

Amount $ Amount $ Amount $

Outputs

Milk, L 0.3 800 240 150d 45 Steer, kg 0.6 102 61 80 48 250 150 Manure, Mg 10/Mg 7 70 5 50 3 30

Inputs

Cow costs 260; 150e 0.2f 52 0.2f 30 1c 60 Stable 40;

30g 0.2h 8 0.2h 8 0.2h 6

Fodder, ha 420 2i 8.4 2i 8.4 Equipment 50 0.3j 15 Missing Missing Overhead 25 0.1 2.5 0.1 2.5 0.1 2.5 Labour, Hd 0.6 191 114.6 157 94.0 107 64.2 Animal feed 75 - - Veterinary care 8 5.5 5 Loss 30 15.6 -

Annual net profit 57.5 -21.0 42.3 Annual profit without paying labour 172.1 73 106.5 a 1 US $ was roughly equivalent to 100 RwF; b Average over 10 years; c In one year one steer calf is reared; d In every two years, 300 litres; e Price

for Ankole/Jersey cross-bred and Improved Ankole, respectively; f Replaced after 5 years; g Price for stables of cow and calf, respectively; h Rebuilt every 5 years; I Replanted every 5 years; j Replaced after 10 years. Source: Minagri 9

440 Journal of Food, Agriculture & Environment, Vol.5 (3&4), July-October 2007

Even with optimal allocation of land and best farm practices, land resources are barely enough for food security. The country must now invest much more in high-input and knowledge- intensive land management to avert famine, to produce surplus for markets, and develop secondary and tertiary sectors. Well- allocated and efficiently used investment is essential for inputs (fertiliser, biocides, high-yielding varieties and breeds, supplementary irrigation, tools and machinery), labour and mechanisation, education and extension, institutional capacity- building, and infrastructure for processing, marketing and trade. Otherwise the country will be permanently dependent on external aid.

Acknowledgements Dr David Dent, Dottore Charles Ndereyehe and Mr Ad van Oostrum M.Sc. are thanked for review of the draft.

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pH (H2O)

SOC P-Olsen Exch. K Control Yield

Application, kg ha-1 Fertiliser costsa

Financial net return

Soil

g kg-1 mg kg-1 mmol kg-1 Mg ha -1 N P K $ $

Gross return/

fertiliser cost

4.7 8 Tr 0.7 0 147 102 86 996 834 1.8 Very acidb

(pH<5.2) 4.7 15 Tr 0.7 0.2 106 99 108 935 791 1.8

5.5 8 2 1.5 1.4 125 73 43 719 465 1.6 5.5 15 2 1.5 2.1 65 51 84 560 333 1.6

Acid (pH 5.3-6.4)

5.5 15 8 3.0 2.9 66 21 25 296 212 1.7

6.5 8 2 1.5 1.5 98 73 76 723 444 1.6

6.5 15 2 1.5 1.8 14 51 105 488 538 2.1

Neutral (pH 6.5-7.3)

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Journal of Food, Agriculture & Environment, Vol.5 (3&4), July-October 2007 441

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