Published on International Journal of Agriculture & Agribusiness
Publication Date: March 18, 2019
Kugedera, A. T.
Great Zimbabwe University, Department of Livestock, Wildlife and Fisheries, Gary Magadzire School of Agriculture and Natural Sciences, P. O. BOX 1235 Masvingo
Zimbabwe Open University, Department of Agriculture Management, Faculty of Agriculture, P. O. BOX 1020 Masvingo
Low crop productivity and inherent soil fertility can be improved by adoption of agroforestry by smallholder farmers. Smallholder farmers are resources poor farmers who are not able to buy large quantities of inorganic fertilisers. Adoption of agroforestry has the potential to transform small arable areas used by smallholder farmers into productive lands. High grain yield can be easily achieved after two –three year of adoption of agroforestry. The only limiting factor for adoption of agroforestry is land hence farmers can use degraded land for agroforestry and transform these lands into productive. In Nigeria the use of agroforestry showed significant increase of maize grain yields from 1.74tha-1 to 2.42tha-1. In Zimbabwe maize grain yields were also improved in Domboshava by use of improved fallow where Acacia anguistissima was used on conventional tillage compared to no tillage systems. Farmers are recommended to adopt agroforestry and start the projects on small scale as agroforestry projects takes two to three years to see the benefits.
Keywords: Adoption, agroforestry, food security, rehabilitation, smallholder & farmers.
Low crop production has been a major threat in smallholder farmers in arid and semi-arid areas of Zimbabwe, with a major concern in region 4 and 5 which widely affect Masvingo. Smallholder farmers in these areas are often faced with low crop productivity, scarcity of fuel wood and fodder. They are only expected to readily adopt agroforestry practices that enable them to increase yields with minimal external inputs (Kabwe, 2010). Agroforestry is the only solution which can reduce the effect of land degradation due to the continual use of inorganic fertilisers by farmers. Adesina et al. (2000) and Mercer (2004) have indicated that adoption and diffusion of agroforestry technologies have lagged behind scientific and technological advances attained, thereby reducing their potential impacts. Adoption of agroforestry also apply to sub-Saharan Africa including countries such as Malawi, Zambia, Tanzania, Mozambique and Zimbabwe is also a part (Ajayi et al., 2006c, Nyamadzawo et al., 2008). Agroforestry has the potential to help many poor resource farmers from poverty. Agroforestry promotion organisations such as International Center for Agroforestry (ICRAF) have introduced several programmes to increase adoption of agroforestry. In Zimbabwe, Domboshava alone had over ten organisations promoting agroforestry technologies (Nyamadzawo et al., 2008). Low adoption levels are not only experienced with agroforestry technologies but also with many other successful agricultural initiatives (Chitakira and Torquebiau, 2007).
Over the past two decades, food production levels in sub-Saharan Africa mostly Zimbabwe have been declining (NEPAD, 2003; Djurfeldt et al., 2005). This has especially affected smallholder farmers, that is, farmers who produce on a small-scale mainly for subsistence and irregularly sell surplus produce. The lagging agricultural productivity growth in sub-Saharan Africa is partly explained by low levels of inputs such as chemical fertilizers, improved seeds and pesticides (Larsson, 2005; Morris et al., 2007). These inputs are too expensive to smallholder farmers due to their low income levels (Mazoyer and Roudart, 2006). In Zambia, nearly 21 percent of the smallholder farmers have been said to have adopted improved fallows (Ajayi et al., 2006). Improved fallows are an agroforestry technology involving the establishment of nitrogen fixing leguminous species during a fallow period of one to three years (Mafongoya et al., 2006). In Zimbabwe agroforestry has been done years ago as a traditional method of improving yield where most people left their parts of fields for 2-3 years not knowing its improved fallowing. Technically, agroforestry was introduced in Zimbabwe formerly some few years ago through ICRAF in Domboshava (Mafongoya et al., 2006a). This is because of the promising research findings for agroforestry to address smallholder farmer problems (Kuntashula et al., 2004; Kwesiga et al., 2003; Mafongoya et al., 2006a; Mafongoya et al., 2006b; Mafongoya et al., 2004; Sanchez, 2002) and the holistic effort by government, international organisations, NGOs and CBOs to extend these technologies to the smallholder farmers (Chitakira and Haruzivishe, 2007; Franzel et al., 2001a; Franzel et al., 2004; Kabwe, 2001; Kabwe et al., 2004, 2010).
2. Review of Literature
Several studies have been done to understand the adoption potential of improved fallows, and to determine factors that affect adoption (Ajayi, 2001; Ajayi and Kwesiga, 2003; Ajayi et al., 2003; Ajayi et al., 2006b; Ajayi et al., 2007b; Ajayi et al., 2007c, 2007d; Franzel, 1999; Franzel et al., 2002a; Franzel et al., 2002b; Franzel et al., 2001b; Kabwe, 2010; Chitakira and Torquebiau, 2010). Some studies have been done in Zambia and Zimbabwe with the same scientists who tried to identify factors affecting adoption of agroforestry technologies in sub- Saharan Africa. The studies showed that most smallholder farmers failed to adopt agroforestry due to lack of interest, land ownership problems and others including time of enjoying results (Chitakira and Torquebiau, 2010). Chikowo (2004) revealed that improved fallows had a great potential of being adopted in the areas where natural fallow periods were decreasing and farmers perceived a decline in soil fertility. Most smallholder farmers cultivate crops, mostly maize, every year regardless of whether they address the soil fertility problem or not (Ajayi et al., 2007b) since this is their only means of sustaining their livelihoods. Soil fertility is one of the primary constraints to smallholder agricultural production in sub-Saharan Africa (Kabwe, 2010; Chitakira and Haruzivishe, 2007; Chikowo, 2004; Parwada et al., 2010). Soil fertility management problems result from continued land degradation that is associated with high population increase and continual use of inorganic fertilisers (Parwada et al., 2010).
Although the use of inorganic fertilizers would be the easiest way to overcome nutrient depletion (Sanchez, 2002), this product is not readily available for use by smallholder farmers because it is expensive. Those farmers who have used inorganic fertilizers to improve soil fertility usually apply it at levels far less than recommended rates (Kwesiga et al., 2003; Mafongoya et al., 2006a; Mafongoya et al., 2006b). However, farmers currently require adding higher quantities of inorganic fertilisers than they did before in order to meet crop needs (Damisa and Igonoh, 2007) but this causes soils to be more acidic creating unfavourable conditions for crop growth. There is need to use organic fertilisers which have a variety of nutrients for crop growth. The unavailability of organic fertilisers in most smallholder farmers due to deforestation causes increased decline in yield and soil fertility. Introduction of agroforestry with the growing of leguminous trees such as Gliricidia sepium, Cajanus cajan and Sesbania sesban which fixes nitrogen improves its availability to soil (Ghee, 2009). Incorporation of biomass from these leguminous trees improves soil conductivity, structure and texture leading to increased infiltration rates and moisture conservation (Nyamadzawo et al., 2003, 2008).
3. Importance of Agroforestry
Today, agroforestry offers a unique set of opportunities for arresting land degradation, and providing ecosystem services in both low-income and industrialised nations (Nair, 2007). The emphasis of agroforestry in developing countries is on alleviating poverty, securing nutritional security and arresting land degradation, particularly under resource-limited conditions and lower-input situations, which cover an estimated 1.9 billion hectares of land and 800 million people (Motis, 2007; Nair, 2007). In the industrialised nations, the primary role of agroforestry is in providing ecosystem services, including water quality control, carbon sequestration, biodiversity conservation, and good land ethics and aesthetics (Garrity, 2006; Mafongoya et al., 2006a).
Agroforestry technologies have high considerable importance in the sub-Saharan African countries because it provides a variety of tree products for domestic use and / or for sale (Kabwe, 2010; Chitakira and Torquebiau, 2010; Motis, 2007). In Zimbabwe most agroforestry trees are grown in farmland, homegardens and even around the yard (Maroyi, 2009). Most of these are fruit trees such as Mangifera indica, Psidium guajava, Upaca karkeana and Citrus limona which smallholder farmers harvest and use as food as well as for selling to get income (Maroyi, 2009). Smallholder farmers also get fire wood, biomass and Non Timber Forest Products (NTFPs) from these trees such as honey. Some smallholder farmers practice apiculture in these agroforestry trees.
Agroforestry plays a significant role in increasing agricultural productivity by nutrient cycling (nutrient mining), reducing soil erosion, and improving soil fertility, conserving water (moisture) and enhancing farm income compared to conventional crop production (Kang and Akinnifesi, 2000; Neupane and Thapa, 2001; Neupane et al., 2002; Chikowo, 2004; Nair, 2007; Nair, 2009; Kabwe, 2010).
Agroforestry can also potentially reduce deforestation while increasing food, fodder ,fuel wood production and controlling climatic conditions such as wind (Neupane and Thapa, 2001; Neupane et al., 2002). Benefits that accrue from usage of agroforestry include food and nutrition security, increased income and assets, improved land management, improve water conservation and soil structure (Nyamadzawo et al., 2003; Garrity, 2006), it also creates environmental and management synergies (Race, 2009, Nair, 2009).
Traditional agroforestry has been practiced for decades by agrarian-based societies throughout the world (Garrity, 2006; Kabwe, 2010). Farmers never noticed it would come in another dimension. The World Bank estimates that 1.2 billion people in the world practice some form of agroforestry on their farms and in their communities some decades ago (World Bank, 2004). Although agroforestry has been practiced by these farming communities for a long time, there is inadequate awareness about its potential to the millions that live in poverty (Garrity, 2006; Mafongoya et al., 2006b). In the past 3 decades, agroforestry has progressed as a science-based pathway for achieving important objectives in natural resource management and poverty alleviation (Garrity, 2006). If it continue to progress well it means most farmers will adopt the technology. To enjoy benefits of agroforestry, there is need for better management because in Europe where traditional agroforestry was stopped some years ago were because of compact management and its composition (Kabwe, 2010). Importance of agroforestry is grouped as environmental and socio-economic benefits (Nair, 2009; Kabwe, 2010).