Socioeconomic and institutional factors influencing adoption of conservation farming by vulnerable households in Zimbabwe

Since 2004, there has been a series of initiatives in Zimbabwe to promote conservation agriculture (CA) through various donor-funded relief initiatives with the aim of improving crop production among vulnerable farmers. In April 2007, the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT) implemented a survey to collect data from 12 districts and 232 households that had been practicing hand hoe-based conservation farming (CF) for at least one prior season with extension and input support from non-governmental organizations. This study was undertaken to better understand the household and institutional factors that influence CF adoption patterns among the beneficiaries of these relief initiatives. Results from the study show that institutional support and agro-ecological location have strong statistical influence on the adoption intensity of different CF components. Besides the practice of preparing basins, at least 70% of the households had also adopted the following components of CF: manure application in the planting basin, topdressing with nitrogen fertilizer at the 5-6 leaf stage of the cereal crop, and timely post-planting weeding. Household labor availability and impacts of HIV/AIDS did not limit the intensity of adoption of CF. An enterprise budget analysis proved that because of the significant yield gains realized with CF, the technology is more viable than conventional tillage practices of broadcasting manure and overall spring tillage on the day of planting. The increased profitability in adopting CF was also reflected in steady increases in the area each household committed to CF from an average area of 1450 m2 in 2004 to more than 2000 m2 in 2007

Reduced tillage and nitrogen effects on soil water dynamics and maize (Zea maysL.) yield under semi-arid conditions

Soil water and nutrients are critical drivers of crop production for smallholders of southern Africa. A three-year study was conducted to assess the effect of integrating single and double ploughing, ripping and planting basins with nitrogen fertilizer (0, 10 and 20 kg N ha–1) on soil water dynamics and maize (Zea mays L.) yields. The experimental design was factorial with four tillage methods and three nitrogen levels as treatment factors. The study was conducted under semi-arid conditions of Zimbabwe. Tillage methods had similar soil water patterns in the profile and no tillage × N interaction effects were observed on soil water dynamics. Soil water penetrated deeper into the profile under ripper and basin methods than conventionally ploughed treatments. Nitrogen increased maize yields (14–96%) and rainwater-use efficiency (20–92%) regardless of tillage methods and growing season quality. However, more studies are required to explore complementary techniques that can improve rainwater capture and prolong soil water storage, and improve soil fertility

Organic material flows within a smallholder highland farming system of South West Uganda

It is now recognised that nutrient losses from the steeply sloping hillsides of the tropics and subtropics occur not only through soil erosion, but through the net transfer of annual crop residues to more profitable parts of the farming system. Studies of soil nutrient balances across Africa are showing evidence of widespread mining of the soil resource within the smallholder farming sector, as the organic matter and nutrient source is not replenished in annually cropped hillside fields. This paper presents information that is central to the understanding of the farming systems employed by smallholder farmers within the highlands of South West Uganda. A time static model of organic resource flows was developed with a smallholder farming community, using visible flow data from farm surveys and semi-structured interviews, to describe this situation. The model explores the sources, whereabouts and current management strategies of organic resources and defines their flow around the farming system. Results confirm a net transfer of 24 Mg ha-1 yr-1 (P<0.01) of organic material, mainly crop yields and residues, from the annually cropped hillsides (covering an area of 0.6 ha per farm (P<0.001)) to other parts of the farming system. The stover from the annual crop is used almost exclusively as mulch in banana (Musa sp.) plantations. As a consequence, the soils on the hillsides are gradually becoming depleted of nutrients, as farmers' place little value on improving the nutrient status of hillside fields distant from homesteads. Households, as is the case with most African subsistence farmers, would rather concentrate their limited labour and organic residue resources in maintaining the fertility/productivity of the more profitable parts of the farming system, in this instance banana plantations and annual fields close to homesteads. Consequently, in the short term the perennial banana system maintains a balanced flux of organic resources at the expense of hillside soil fertility. Unfortunately, over the longer term the current system will inevitably lead to a severe reduction in mulch availability, which will mean perennial crop yields will eventually decline, leading potentially, towards an unsustainable farming system. Fortunately, however, there are under-exploited organic resources within the existing farming system, that if fully utilised and could help sustain and even improve the yields of both annual and perennial crops. The whereabouts, management and value of these organic resources need to be highlighted to farmers so that alternative management strategies for organic residues can be developed, that are both economically appropriate to the farmer and the resources available, at farm level

Improving Soil Management Options for Women Farmers in Malawi and Zimbabwe : Proceedings of a Collaborators' Workshop on the DFID-supported Project "Will Women Farmers Invest in Improving their Soil Fertility Management? 13-15 September 2000

The collaborators' workshop held in September 2000 in Zimbabwe brought together stakeholders from Malawi, Zimbabwe, and UK, who actively participated in the Department for International Development (DFID)-supported project "Wi l l women farmers invest in improving their soil fer t i l i ty management? Participatory experimentation in a risky environment." The objectives of the workshop were to review and discuss the project results achieved during the 1999/2000 cropping season, assess how these results contributed to the project outputs, and agree work plans that better target the needs of women farmers in the activities during the following seasons

The nexus between integrated natural resources management and integrated water resources management in southern Africa

The low productivity of smallholder farming systems and enterprises in the drier areas of the developing world can be attributed mainly to the limited resources of farming households and the application of inappropriate skills and practices that can lead to the degradation of the natural resource base. This lack of development, particularly in southern Africa, is of growing concern from both an agricultural and environmental perspective. To address this lack of progress, two development paradigms that improve land and water productivity have evolved, somewhat independently, from different scientific constituencies. One championed by the International Agricultural Research constituency is Integrated Natural Resource Management (INRM), whilst the second championed predominantly by Environmental and Civil Engineering constituencies is Integrated Water Resources Management (IWRM). As a result of similar objectives of working towards the millennium development goals of improved food security and environmental sustainability, there exists a nexus between the constituencies of the two paradigms, particularly in terms of appreciating the lessons learned. In this paper lessons are drawn from past INRM research that may have particular relevance to IWRM scientists as they re-direct their focus from blue water issues to green water issues, and vice-versa. Case studies are drawn from the management of water quality for irrigation, green water productivity and a convergence of INRM and IWRM in the management of gold panning in southern Zimbabwe. One point that is abundantly clear from both constituencies is that ‘one-size-fits-all’ or silver bullet solutions that are generally applicable for the enhancement of blue water management/formal irrigation simply do not exist for the smallholder rainfed system

The influence of conservation tillage methods on soil water regimes in semi-arid southern Zimbabwe

Planting basins and ripper tillage practices are major components of the recently introduced conservation agriculture package that is being extensively promoted for smallholder farming in Zimbabwe. Besides preparing land for crop planting, these two technologies also help in collecting and using rainwater more efficiently in semi-arid areas. The basin tillage is being targeted for households with limited or no access to draught animals while ripping is meant for smallholder farmers with some draught animal power. Trials were established at four farms in Gwanda and Insiza in southern Zimbabwe to determine soil water contributions and runoff water losses from plots under four different tillage treatments. The tillage treatments were hand-dug planting basins, ripping, conventional spring and double ploughing using animal-drawn implements. The initial intention was to measure soil water changes and runoff losses from cropped plots under the four tillage practices. However, due to total crop failure, only soil water and runoff were measured from bare plots between December 2006 and April 2007. Runoff losses were highest under conventional ploughing. Planting basins retained most of the rainwater that fell during each rainfall event. The amount of rainfall received at each farm significantly influenced the volume of runoff water measured. Runoff water volume increased with increase in the amount of rainfall received at each farm. Soil water content was consistently higher under basin tillage than the other three tillage treatments. Significant differences in soil water content were observed across the farms according to soil types from sand to loamy sand. The basin tillage method gives a better control of water losses from the farmers’ fields. The planting basin tillage method has a greater potential for providing soil water to crops than ripper, double and single conventional ploughing practice