Soil Fertility Management Strategies Research Articles

An ethnographic exploration of the impacts of HIV/AIDS on soil fertility management among smallholders in Butula, western Kenya

This paper shows how HIV/AIDS negatively affects soil fertility management strategies among Kenyan smallholders. The paper examines this relationship, using ethnographic interviews of purposively selected affected households in Butula Division, Busia District, Kenya. Soil fertility management was given low priority in the face of high HIV/AIDS prevalence although it is a critical resource for meeting basic needs. Findings show that HIV/AIDS poses a significant and complex threat to the already deficient soil fertility management practices among smallholders. The disease's synergistic relation with poverty increases the stress on soil fertility management. It destructs local social structures and households by taking away resource persons, overburdening traditional insurance systems, and obliterating any modest capital and labour useful for soil fertility management that has been accumulated by the household. There is need for robust soil fertility policy-action frameworks that can be sustained under the limiting conditions of affected households and that can mitigate HIV/AIDS impacts amidst high poverty.

Sécurité foncière et gestion de la fertilité des sols : études de cas au Ghana et au Bénin

Within the framework of a larger research programme, Convergence of Sciences (CoS), studies were conducted on soil fertility management strategies in Ghana (Wenchi area) and Benin (Save area). Soil fertility management in both areas includes short-term and longer-term practices. Both regions are characterised by the presence of natives and various groups of migrants that differ in their livelihood strategies. Natives and migrants enter into various tenure relationships. Driven by the increasing monetisation of the economy, such arrangements have evolved from land-for-labour relationships to a more monetary system,. In general natives claim that migrants are negatively affecting soil fertility through their cropping practices, while migrants claim that the nature of the tenure arrangement leads to insecurity and leaves them no choice but to mine the soil. There is, hence, widespread mistrust between natives and migrants, and the prospects for durable tenure arrangements that could maintain soil fertility seem limited. However, recognition of mutual interdependence could form a basis for the build-up of trust. In this study we highlight similarities and differences between the two areas in terms of livelihood strategies of migrants, soil fertility management practices and tenure arrangements. We also indicate the way in which alternative soil fertility management strategies could be effected under different tenure arrangements and describe the negotiation processes that have been started with a view to implementing such alternatives.

Socio-economic Factors, Soil Fertility Management and Cropping Practices in Mixed Farming Systems of Sub-Saharan Africa: A Study in Kiambu, Central Highlands of Kenya

A study was carried out in Kiambu District, central highlands of Kenya to explore the effects of household socio-economic factors on farm nutrient balances and agro-economic performance and to determine nutrient depleting and conserving cropping practices in the crop-dairy (mixed) farming system. Data was collected from 30 smallholder farmers and processed using nutrient monitoring (NUTMON) tool. Family earnings (sum of net farm income and off-farm income) were low and off-farm income accounted for 61% of family earnings of the studied households. On-farm livestock density (TLU ha-1) was the main determinant of farm N, P and K nutrient stocks and balances. The mean farm (total) nutrient balances were -2.6 kg N ha-1 half year-1, 36.7 kg P ha-1 half year-1 and 16.9 kg K ha-1 half year-1. In the analysis, purchased livestock feeds (and fertilizers) were the major determinants of farm N, P and K nutrient balances. The major loss pathway for P and K was erosion, accounting for 35 and 66% of total P and K outflows respectively. For N, it was leaching. Farmers adopted preferential soil fertility management strategies for cropping practices resulting in nitrogen, phosphorus and potassium nutrient mining under Napier (monocrop) and coffee (intercrop) fields and nutrient conservation under maize (intercrop) fields.

Profitability of Kale and Tomato Production Under Different Soil Fertility Replenishment Technologies in Western Kenya

ABSTRACT A structured questionnaire was administered to 160 farmers from the Kakamega and Vihiga districts of Western Kenya using a purposive random sampling technique to assess the profitability of different soil fertility management strategies for kale and tomato production systems. Different soil fertility amendment technologies including the use of manure, chemical fertilizer and biomass materials, alone and in combination, were compared. Use of farm yard manure alone was considered as a baseline strategy to show the extra costs and returns incurred by farmers if they decided to invest in additional technologies for kale and tomato production. Partial budgets were constructed in order to analyze marginal changes that occur in benefits and costs due to the introduction of improved technology. Kale production was found to be most profitable when grown using a combination of manure and chemical fertilizer to replenish soil fertility. This combination (manure and chemical fertilizer) also yielded the highest marginal rate of return (MRR) of 1,758% in kale production. In the case of tomato production, the most profitable system is farm yard manure, chemical fertilizer and Tithonia diversifolia biomass transfer, which gave a net return of US$256 per year per hectare. This shows that it was profitable to shift from use of farm yard manure to a combination of farm yard manure, chemical fertilizer and Tithonia diversifolia biomass transfer. The study thus shows that it is profitable for the farmers to combine farm yard manure and any other soil fertility replenishment strategy in both kale and tomato production. The study thus recommends the need for the farmers to be encouraged to use available and relatively cheap soil fertility replenishment technologies. Further, there is need for the farmers to propagate the Tithonia diversifolia plant on their farms.

Indicators of soil quality: A South–South development of a methodological guide for linking local and technical knowledge

The increasing attention paid to local soil knowledge results from a greater recognition that farmer knowledge can offer many insights into the sustainable management of tropical soils and that the integration of local and technical knowledge systems helps extension workers and scientists work more closely with farmers. A participatory approach and a methodological guide were developed to identify and classify local indicators of soil quality and relate them to technical soil parameters, and thus develop a common language between farmers, extension workers and scientists. This methodological guide was initially developed and used in Latin America and the Caribbean-LAC (Honduras, Nicaragua, Colombia, Peru, Venezuela, Dominican Republic), and was later improved during adaptation and use in eastern African (Uganda, Tanzania, Kenya, Ethiopia) through a South–South exchange of expertise and experiences. The aim of the methodological guide is to constitute an initial step in the empowerment of local communities to develop a local soil quality monitoring and decision-making system for better management of soil resources. This approach uses consensus building to develop practical solutions to soil management constraints identified, as well as to monitor the impact of management strategies implemented to address these constraints. The particular focus on local and technical indicators of agroecosystem change is useful for providing farmers with early warnings about unobservable changes in soil properties before they lead to more serious and visible forms of soil degradation. The methodological approach presented here constitutes one tool to incorporate local demands and perceptions of soil management constraints as an essential input to relevant research for development activities. The participatory process followed was effective in facilitating farmer consensus; for example, about which soil related constraints were most important and what potential soil management options could be used. Development of local capacities for consensus building constitute a critical step prior to collective action by farming communities resulting in the adoption of integrated soil fertility management strategies at the farm and landscape scale.

Mineralogy and Fertility Status of Selected Soils of the Eastern Cape Province, South Africa

Thorough knowledge of cultivated soils is necessary for their informed and sustainable management. This study was carried out to gain a better understanding of cropped soils in the Eastern Cape Province of South Africa. The mineralogical and chemical composition and nutrient status of topsoils collected from homestead gardens and fields of smallholdings in 5 of the 36 magisterial districts where smallholder farming prevails in the Province were determined. These data were supplemented with results of soil analyses conducted by an Analytical Services Laboratory that obtains its samples from the 31 magisterial districts where large‐scale farms are dominant. The soils studied were similar mineralogically, and all had a clay fraction that was dominated by quartz, mica, and/or kaolinite, which is fairly typical for many tropical and subtropical soils. Elemental analysis showed that the soils were generally low to very low in their total content of nutrients, except for sulfur (S), manganese (Mn), zinc (Zn), copper (Cu), and boron (B), reflecting the marine and sedimentary nature of their parent materials. The available nutrient status of the cultivated soils was generally low to very low, especially those found in smallholder fields. This was attributed to low soil organic matter levels and low geological reserves of some nutrients notably phosphorus (P), potassium (K), and calcium (Ca), coupled with continuous cultivation of the lands without adequate nutrient replenishment. Depending on location, 75–100% of the fields tested low in pH, 62–100% were low in organic carbon, 83–100% were low in extractable K, 62–93% were low in extractable Ca, and 79–100% were deficient in available phosphorus. The nutrient status of soils receiving moderate to high amounts of nutrients was generally satisfactory, as revealed by the nutrient content of garden soils found on smallholdings and the fields on large‐scale farms. In all cases, soil pH was low to critically low. The findings are used to propose a soil fertility management strategy for the communal areas of the Province.

Soil fertility management strategies on the Jos Plateau: the need for integrating ‘empirical’ and ‘scientific’ knowledge in agricultural development

Tin mining carried out on the Jos Plateau since the beginning of the last century has disturbed some 320 km2 of agricultural land. Formal attempts at reclamation of this land failed, but local farmers have developed a successful informal strategy for reclamation. This paper reports on a study undertaken to comprehend the farmers’‘informal’ approach to soil fertility management. Their soil fertility management practices centre on the use of a complex combination of traditional organic manures and ‘modern’ inorganic fertilizers that they have developed entirely on the basis of experimentation. A central focus of this paper is therefore the empirical knowledge base of the farmers and an assessment of any underlying scientific explanations for their strategies, including an analysis of their assertion that different brands of NPK fertilizers differ in their nutrient value. This discussion is followed by a consideration of the difficulties in accessing and understanding empirical knowledge. It is concluded that farmers’ knowledge and understanding of the values of different fertilizers and manures does have a scientific basis. It is argued that for further agricultural development to take place on the Jos Plateau, there must be synergy between farmers’ empirical knowledge (which has led to the development of successful and effective soil fertility management strategies, unlike the attempts of the local ‘scientific’ communities) and scientific knowledge (which can identify health and environmental hazards which may not be immediately visible to farmers).

Resource flows and nutrient balances for crop and animal production in smallholder farming systems in eastern Uganda

Resource flow models are useful tools that assist farmers in analysing their soil fertility management strategies and in planning, experimenting and adapting ways to improve the use of scarce local resources. Resource flows and farm nutrient balance studies were carried out in eastern Uganda to ascertain the movement of organic resources and nutrients in and out of the farm system during a participatory learning and action research (PLAR) process. The resource flows were transformed into nutrient flows and partial nutrient balances were calculated using the Resource Kit computer package. Results of a farmers’ soil fertility management classification at the start of the PLAR intervention in 1999 revealed that 3% of the farmers were good soil fertility managers (class I), 10% were average soil fertility managers (class II) and 87% were poor soil fertility managers (class III). The results indicate that the net farm nutrient balances in kg ha 1 per season for all the nutrients [nitrogen (N), phosphorus (P), and potassium (K)] were negative for both the good and the poor soil fertility managers. Class 1 farm balances irrespective of the season, were however more negative than those of class 3 farms. For the long rains seasons (LR 2000, 2001 and 2002), the average net farm nutrient balances for N, P, and K for class I farms were5.0,0.6 and8.0 kg ha 1 year 1 , while for the short rains seasons (SR 2000 and 2001), the nutrient balances were 3.5, 0.5 and 6.0 kg ha 1 year 1 , respectively. For the class III farms, the average net farm nutrient balances for N, P, and K in the long rain seasons (LR 2000, 2001 and 2002) were 3.3, 0.3 and 4.0 kg ha 1 year 1 while for the short rains seasons (SR 2000 and 2001), the nutrient balances were 3.5, 0.5 and 5.0 kg ha 1 year 1 , respectively. Soil management interventions for these small-scale farmers should aim at reversing nutrient depletion with a focus on profitable management of the crop production system, which is the major cause of nutrient depletion.

Exploring diversity in soil fertility management of smallholder farms in western Kenya

Abstract The processes of nutrient depletion and soil degradation that limit productivity of smallholder African farms are spatially heterogeneous. Causes of variability in soil fertility management at different scales of analysis are both biophysical and socio-economic. Such heterogeneity is categorised in this study, which quantifies its impact on nutrient flows and soil fertility status at region and farm scales, as a first step in identifying spatial and temporal niches for targeting of soil fertility management strategies and technologies. Transects for soil profile observation, participatory rural appraisal techniques and classical soil sampling and chemical analysis were sampled across 60 farms in three sub-locations (Emuhaia, Shinyalu, Aludeka), which together represent much of the variability found in the highlands of western Kenya. Five representative farm types were identified using socio-economic information and considering production activities, household objectives and the main constraints faced by farmers. Soil fertility management and nutrient resource flows were studied for each farm type and related to differences in soil fertility status at farm scale. Farm types 1 and 2 were the wealthiest; the former relied on off-farm income and farmed small pieces of land (0.6–1.1 ha) while the latter farmed relatively large land areas (1.6–3.8 ha) mainly with cash crops. The poorest farm type 5 also farmed small pieces of land (0.4–1.0 ha) but relied on low wages derived from working for wealthier farmers. Both farm types 1 and 5 relied on off-farm earnings and sold the least amounts of farm produce to the market, though the magnitude of their cash, labour and nutrient flows was contrasting. Farms of types 3 and 4 were intermediate in size and wealth, and represented different crop production strategies for self-consumption and the market. Average grain yields fluctuated around 1 t ha−1 year−1 for all farm types and sub-locations. Grain production by farms of types 4 and 5 was much below annual family requirements, estimated at 170 kg person−1 year−1. Household wealth and production orientation affected the pattern of resource flow at farm scale. In the land-constrained farms of type 1, mineral fertilisers were often used more intensively (ca. 50 kg ha−1), though with varying application rates (14–92 kg ha−1). The use of animal manure in such small farms (e.g. 2.2 t year−1) represented intensities of use of up to 8 t ha−1, and a net accumulation of C and macronutrients brought into the farm by livestock. In farms of type 5, intensities of use of mineral and organic fertilisers ranged between 0–12 kg ha−1 and 0–0.5 t ha−1, respectively. A consistent trend of decreasing input use from farm types 1–5 was generally observed, but nutrient resources and land management practices (e.g. fallow) differed enormously between sub-locations. Inputs of nutrients were almost nil in Aludeka farms. Both inherent soil properties and management explained the variability found in soil fertility status. Texture explained the variation observed in soil C and related total N between sub-locations, whereas P availability varied mainly between farm types as affected by input use.

Effects of soil management practices on soil fertility measurements on Agave tequilana plantations in Western Central Mexico

Agaves have historically been an important crop in the Western Central Highlands of Mexico, used for food, livestock fodder and beverage production. The best known of these products, and one of the most financially significant, is the distilled spirit, Tequila. The success of agaves in this region has been attributed, in part, to unique environmental adaptations. Agaves used for production of the distilled spirit Tequila (Blue agave) have also been considered to have a minimal impact on soil fertility because they are harvested only every 6–10 years. In the past 20 years, with the rising global consumption of Tequila, cultivation of Blue agaves has grown more intense, prompting questions regarding the impact of commercial practices on soil quality. Researchers on related agave species have shown the potential for severe nutrient depletion and subsequent declines in yield in the absence of proper soil fertility management. This study examined the key physical and chemical indicators of soil fertility and how they were affected by tillage, the amendment of soils with distillery effluent, and the grazing of livestock. It was found that tillage decreased soil carbon levels along with nutrients associated with organic matter; mean levels of 2.44% C, 0.20% N and 10.99 mg P/kg soil were found on untilled sites compared with 1.29% C, 0.10% N and 3.53 mg P/kg soil for tilled sites. The addition of distillery effluent was found to increase soil cation levels (mean soil K, Mg, and Ca were 436.50, 364.40 and 1416.2 mg/kg on amended sites versus 299.50, 228.36 and 1013.5 mg/kg on non-amended sites) while livestock grazing had only a small effect on nutrient levels. The effects of tillage and livestock grazing need to be addressed by proper soil fertility management strategies need to be addressed to insure the long term health of soils in the region.

Efficient use of resources: urban waste ash and soil fertility on the Jos Plateau, Nigeria

Waste disposal constitutes an acute problem in numerous African cities. One solution could lie in the recycling of the nutrient‐rich waste into agriculture taking place in and around cities. Farmers involved in vegetable production around Jos, Nigeria, have developed a sophisticated soil fertility management strategy combining inorganic fertilizers, manure and urban waste ash. This paper: (1) investigates the socio‐economic constraints linked to obtaining scarce organic inputs, particularly urban waste ash and the health hazards (particularly heavy metal contamination of soil and crops) caused by using this ash and (2) suggests ways to improve use of this important resource.

Land tenure and differential soil fertility management practices among native and migrant farmers in Wenchi, Ghana: implications for interdisciplinary action research

In the past, farmers in the forest-savannah transitional agro-ecological zone of Ghana relied on the bush fallow system for maintaining the productivity of their farmland. However, in recent years population growth-induced pressure on land has increased and farmers have developed various other strategies for improving the productivity of their farmlands. Such strategies have been identified in the context of an interdisciplinary action research project and include rotations with cassava ( Manihot esculenta), pigeon pea ( Cajanus cajan) and cowpea ( Vigna unguiculata). Using a social science model for understanding technical farming practices, this article explains the differential adoption of these locally developed soil fertility management strategies. It transpires that native and migrant communities are captured in a social dilemma situation, which has negative consequences for soil fertility in that promising innovations are not utilized optimally. Based on this research experience, this article concludes with a discussion of the implications for co-operation between natural and social scientists in the context of interactive action research. It is argued, amongst other things, that the essence of such co-operation lies in the critical questioning and influencing of each other's key assumptions and disciplinary research agendas.

Nutrient Dynamics

Summary Environmental concerns currently trigger the development of more sustainable soil fertility management strategies. It appears that effective sustainable practices are those that enhance natural soil processes. Soil processes include the decomposition of residues and mineralization of organic matter, nitrogen fixation, nitrification, nitrate leaching, denitrification and sulfur reduction. Natural soil processes also include less well-understood interactions, namely, those leading to the dissolution of minerals by organic acids, as well as rhizospheric and mycorrhizospheric interactions. Plants, associated with arbuscular mycorrhizal symbionts, supply and distribute carbon and energy, sustaining most of the biotic mechanisms responsible for nutrient release from soil, and maintaining organic pools of nutrients. Among these pools, the microbial biomass and fine roots pools, with their very fast turnover time, are particularly important as they can maintain large amounts of nutrients in very labile form and, therefore, increase soil fertility. Agricultural soil systems are very dynamic and are characterized by large spatial and temporal variations, which are largely driven by plant development. In addition, nutrient dynamics in agricultural soil systems seem particularly influenced by temperature, moisture, and nitrogen and phosphorus fertilization. Nitrogen losses from soil are reduced in systems where nitrogen release corresponds to plant demand. Biological nitrogen fixation is a sound way to input nitrogen in cropping systems. Phosphorus losses can be reduced through increased reliance on the arbuscular mycorrhizal symbiosis of crops. Soils are diverse and complex systems, which, furthermore, respond to increasingly unpredictable climatic variations. Optimal agricultural soil management is a moving target and, hence, a challenging goal that will never be totally reached.

Adoption of improved maize varieties in the hills of Nepal

AbstractMaize (Zea mays L.) is the most important cereal crop in the hills of Nepal, where the grain is used for human consumption and the stover for animal fodder. Maize farms are small, and population pressure necessitates the intensification of existing farming systems. Maize research directed at developing technologies for maize production began in Nepal in 1965. In 2000, a survey was carried out in two districts to determine the current level of adoption of improved maize production practices. In each of these districts, remote and accessible village development committees (VDCs) were surveyed. Questionnaires were administered to 54 randomly selected households in each VDC. A Tobit analysis was used to determine socio‐economic, physical and technology factors that influence the use of improved varieties by farmers. All households use composted farmyard manure, and in the more accessible areas, urea as part of their soil fertility management strategy. Use of improved varieties was less than 60% for all VDCs and only 15% in the most remote VDC. In three of the four VDCs, adoption of improved varieties primarily occurred during the past 5 years. Based on a Tobit analysis, Khet land area, ethnic group, years of fertiliser use, off‐farm income, and contact with extension significantly and positively affected adoption of improved varieties. Farmers in VDCs in central Nepal reported lack of seed to be the major constraint to the adoption of improved varieties, while lack of knowledge of new varieties was the major constraint for farmers in the western VDCs. The results from this survey suggest that the strategy for improving the adoption of new varieties will differ depending on infrastructure and the socio‐economic conditions of the farmers in a given area.

Adoption of improved maize varieties in the hills of Nepal

Maize ( Zea mays L.) is the most important cereal crop in the hills of Nepal, where the grain is used for human consumption and the stover for animal fodder. Maize farms are small, and population pressure necessitates the intensification of existing farming systems. Maize research directed at developing technologies for maize production began in Nepal in 1965. In 2000, a survey was carried out in two districts to determine the current level of adoption of improved maize production practices. In each of these districts, remote and accessible village development committees (VDCs) were surveyed. Questionnaires were administered to 54 randomly selected households in each VDC. A Tobit analysis was used to determine socio-economic, physical and technology factors that influence the use of improved varieties by farmers. All households use composted farmyard manure, and in the more accessible areas, urea as part of their soil fertility management strategy. Use of improved varieties was less than 60% for all VDCs and only 15% in the most remote VDC. In three of the four VDCs, adoption of improved varieties primarily occurred during the past 5 years. Based on a Tobit analysis, Khet land area, ethnic group, years of fertiliser use, off-farm income, and contact with extension significantly and positively affected adoption of improved varieties. Farmers in VDCs in central Nepal reported lack of seed to be the major constraint to the adoption of improved varieties, while lack of knowledge of new varieties was the major constraint for farmers in the western VDCs. The results from this survey suggest that the strategy for improving the adoption of new varieties will differ depending on infrastructure and the socio-economic conditions of the farmers in a given area.

Chemical properties of urban waste ash produced by open burning on the Jos Plateau: implications for agriculture

Urban centres produce most of the world's waste and between a third and a half goes uncollected. The answer to the problem of waste disposal lies partly in agriculture, as waste can be extremely nutrient-rich. In the last decade there has been a tremendous increase in the developing world in total city area under informal food production and there are many examples of waste recycling onto the urban or peri-urban plots. Farmers on the Jos Plateau, Nigeria, have developed a successful soil fertility management strategy based on the combination of inorganic fertilisers, manure and urban waste ash. This study sought to provide some preliminary data on urban waste ash produced by open burning and used in farming in a developing country. Ash samples were collected from different locations around Jos and tested for C, N, pH, P, Na, K, Ca, Mg, Fe, Mn, Zn, Cu, Ni, Cd and Pb. It was found that ash is an effective liming material (because of the high pH, and high Ca, Mg and K contents), and has the potential to contribute significant quantities of micro-nutrients such as Mn, Zn and Cu. Ash, however, is far from being a homogenous material and its variability means that its fertilising potential will vary between batches and that, even if mean and median levels are low, there is the risk of the formation of localised areas of soil with excessive heavy metal contents (this is particularly the case with Pb). Further research is required to determine the plant-availability of these elements in the ash and to assess the wider environmental and health implications of uncontrolled, open burning of waste as a means of producing ash for agricultural purposes.

Fertilizer market reforms and factors influencing fertilizer use by small-scale farmers in Bénin

Bénin, like other countries in sub-Saharan Africa, has initiated programs to reform agricultural input and output markets. While the impact of the reform programs has been different for each country, it is commonly observed that impact at the farm level has been less than anticipated. A central theme of this paper is to assess the impact of fertilizer market reforms on the fertilizer market structure and fertilizer use for both food and export (cotton) crop production in Bénin. This analysis of farm-level policy impact is based on data from 899 farm households randomly selected and interviewed in all six départements of Bénin in 1998/1999. Results of the study show that there have been only insignificant changes in the fertilizer market structure. Access to fertilizers has not improved; prices for fertilizer have risen in real terms, resulting in application rates lower than that recommended by extension agents. The effects of the reform programs are vital for investment decisions and provide lessons for introducing alternative approaches for improving soil fertility or management. Since 1992, 54% of farmers find maize ( Zea mays L.) production more profitable, while 38% reported that cotton ( Gossypium hirsutum L.) production has become more profitable. As a result of the mixed effects of the fertilizer market reform program on the level of fertilizer use and profitability, there is need to develop efficient soil fertility management strategies for small-scale farmers. Such strategies should incorporate the use of complementary inputs, such as seeds with a high level of response to the balanced nutrient package.

Impact of Soil Fertility Management Strategies on Diversity and Populations Soil Macrofauna in an Agroecosystem

The role of soil invertebrate fauna in decomposition of organic residues and thus nutrient release, soil structure and soil-water relations is well appreciated. The scope, however, of their manipul...

MANAGEMENT OF MANURE IN FARMING SYSTEMS IN SEMI-ARID WEST AFRICA

The last 50 years have seen a rapid expansion of cultivated area in semi-arid areas of West Africa. This has precipitated a change from traditional fallowing to more pro-active soil fertility management techniques. Smallholder farmers employ a range of technologies to enhance soil fertility and manure is a cornerstone of many of the soil fertility management strategies they use. This paper reviews manure management by smallholder farmers. It considers factors that affect the quality of the manure used, including methods for keeping livestock and storing manure. The paper reviews the strategies, such as night parking and crop-livestock integration, which farmers employ to ensure that manure reaches their fields. The nutrient balances of two farming systems are presented as evidence for the importance of manure as a nutrient source. Rangeland-to-cropland nutrient transfers are contrasted with nutrient recycling through crop-livestock integration. The paper concludes that within the constraints in which smallholder farmers operate in semi-arid West Africa, manure will remain an important component of soil fertility management strategies for the foreseeable future. Integrated nutrient management strategies that take into consideration the circumstances of farmers, and the resources available to them, are the best way forward. Appropriate interventions need to focus on improving manure management to ensure that the material which farmers so laboriously prepare and transport is of the best possible quality.

Farming with reduced synthetic chemicals in North Carolina

AbstractThe primary objectives of this study were to describe the various pest control and soil fertility management strategies used by North Carolina farmers and to characterize the types of farms and farmers using each strategy. In 1988, a survey was mailed to farmers who had shown interest in alternative methods and a randomly selected control group of conventional farmers. Cluster analysis on crops, inputs, and cultural practices used by crop farmers in the combined sample showed that they fall into three distinct groups. Very few members of the first group apply standard synthetic fertilizers and pesticides. Instead, more than three-quarters of them use cover crops, compost, organic mulch, commercial fertilizers and pesticides labeled as “organic”, resistant varieties, hand weeding, mechanical cultivation, scouting, and biological pest controls. More than half of the second group did not use any nutrient and pest management inputs or practices except synthetic fertilizers, herbicides, and lime. More than three-quarters of the third group reported use of synthetic fertilizers, synthetic herbicides, and lime, but also employed most of the cultural practices reported by alternative farmers. However, they less frequently used labor-intensive practices (such as manuring, mechanical cultivation, and hand weeding) and information-intensive practices (such as scouting and companion planting). Information sources, concerns about farm chemicals, and length of farming experience discriminated better than other socioeconomic factors and farm characteristics between farmers who use conventional chemical inputs and those who use alternative practices. Group 1 farmers differed from Group 3 farmers most sharply in that they rank the cost of pest control products and their extension agents' advice lower, have lower farm incomes, read more information sources promoting reduced synthetic chemicals, own more of the land they operate, and have less farming experience. The only factors significantly discriminating Groups 1 and 2 were that Group 1 fanners rank the importance of their extension agents' recommendations lower and effects of chemical products on birds and wildlife higher, read more reduced-chemical information sources, and have less farming experience.