Tag: gliricidia sepium
Institutional Perspectives of Climate-Smart Agriculture: A Systematic Literature Review
Climate-smart agriculture (CSA) is increasingly seen as a promising approach to feed the growing world population under climate change. The review explored how institutional perspectives are reflected in the CSA literature. In total, 137 publications were analyzed using institutional analysis framework, of which 55.5% make specific reference to institutional dimensions. While the CSA concept encompasses three pillars (productivity, adaptation, and mitigation), the literature has hardly addressed them in an integrated way. The development status of study sites also seems to influence which pillars are promoted. Mitigation was predominantly addressed in high-income countries, while productivity and adaptation were priorities for middle and low-income countries. Interest in institutional aspects has been gradual in the CSA literature. It has largely focused on knowledge infrastructure, market structure, and hard institutional aspects. There has been less attention to understand whether investments in physical infrastructure and actors’ interaction, or how historical, political, and social context may influence the uptake of CSA options. Rethinking the approach to promoting CSA technologies by integrating technology packages and institutional enabling factors can provide potential opportunities for effective scaling of CSA options.
Audited Financial Statements 2014
The research and development work of the Centre spans global, regional, national, sub-national and local scales. ICRAF operates six regional programmes through the following Regional Network Offices:• East and Southern Africa Region;• West and Central Africa Region;• South East Asia Region;• East and Central Asia Region; • South Asia Region; and• Latin America Region
Agroforestry research and development in southern Africa during the 1990s: Review and challenges ahead
The International Centre for Research in Agroforestry (ICRAF) initiated in 1987 the Southern Africa Regional Agroforestry Programme in partnership with the national research systems in Malawi, Zambia, Zimbabwe and Tanzania to address the problems of low soil fertility and consequent low crop and livestock production, low cash income, and shortages of fuelwood and timber that are common to most rural households in the region. This paper synthesizes agroforestry research and development during the 1990s from a regional perspective and emphasizes scaling-up of promising technologies. The problem of nutrient-depletion can be overcome using nitrogen-fixing and fast growing tree/shrub species, such as Sesbania sesban, Tephrosia vogelii and Gliricidia sepium, as short-duration planted fallows in rotation with crops. Intercropping of food crops with coppicing trees, annual relay intercropping and biomass transfer technologies were found to be appropriate for soil fertility improvement under specific conditions. Tree fodder banks greatly increase fodder production and enrich livestock diets with protein supplements. Rotational woodlots were developed to meet fuelwood and timber demand and reduce pressure on natural woodlands. Research has identified the potential for a number of indigenous fruits in the region to supplement the food needs of rural families, improve their nutritional status and generate cash income. Achieving the ultimate goals of ensuring food security, alleviating poverty and sustaining the environment will require a massive scaling up of adoption of these agroforestry technologies. Key strategies to accomplish this include: increasing the benefits and targeting of agroforestry technologies (for example, through providing substitutes for costly inputs, improving diversification, marketing and processing of agroforestry products, and employing GIS-based targeting techniques) and information-sharing, training and collaborative partnerships in implementation and dissemination of agroforestry options with all major stakeholders (farmers, non-government organizations, extension services, educational institutions, and policy-makers).
Fertiliser trees for sustainable food security in the maize-based production systems of East and Southern Africa. A review
The negative effects of soil fertility depletion on food security, especially among smallholder farmers in Africa, is of economic importance, and may be worsened by climate change and rising global fertiliser prices. Substantial efforts and investment have gone into development of alternative soil fertility management options. These include vigorous research and development of N-fixing plants or “fertiliser trees”, that has been on-going in the last two decades in East and Southern Africa. In this paper, we review several studies conducted both on-station and on-farm and synthesise the results in terms of improvements in soil physical, chemical and biological properties, and crop yield in response to fertiliser trees. Our major findings are that (1) fertiliser trees add more than 60 kg N ha-1 per year through biological nitrogen fixation (BNF); (2) nutrient contributions from fertiliser tree biomass can reduce the requirement for mineral N fertiliser by 75%, translating to huge savings on mineral fertilisers; (3) fertiliser trees were also shown to substantially increase crop yield. A meta-analysis has further provided conclusive evidence that with good management, fertiliser trees can double maize yields compared with local farmer practices of maize cultivation without addition of external fertilisation. (4) Financial analyses showed that fertiliser tree systems are profitable and also have higher net returns than the farmers’ de facto practice, i.e. continuous maize cropping without fertiliser. We conclude that widespread adoption and scaling up of fertiliser trees can reduce the amount of mineral fertiliser needed, maintain the soil ecosystem, and positively impact on the livelihoods of farm households in southern Africa.
Legumes for improving maize yields and income in semi-arid Kenya
An experiment was conducted at the research station of the International Centre for Research in Agroforestry (ICRAF) at Machakos, Kenya from November 1989 to February 1996 to evaluate the effect of annual and perennial legumes on soil fertility, cereal yields and economic returns. The study evaluated six cropping systems: (1) continuous sole maize, (2) maize rotated with short-duration legume, cowpea (Vigna unguiculata L. Walp.), (3) maize rotated with long-duration legume, pigeonpea (Cajanus cajan L. Millsp.), (4) maize intercropped with pigeonpea, (5) hedgerow intercropping of maize and a perennial legume, gliricidia (Gliricidia sepium), and (6) continuous sole maize, green-manured with gliricidia prunings produced from an equivalent area outside the cropped field (‘biomass transfer technology’). Maize–cowpea sequential and pigeonpea/maize intercropping systems produced, respectively, 17 and 24% higher maize yields than continuous sole maize, but maize–pigeonpea rotation yielded only marginally better. Hedgerow intercropping did not increase maize yields because increased yields during the few high rainfall seasons did not compensate the yield losses in other seasons due to the competition of hedgerows for water with crop. Green manuring with gliricidia prunings increased maize production by 27%, but this technology was not economical because of high labour costs for production and application of prunings to the crop. The annual grain legume-based cropping systems were 32–49% more profitable than continuous sole maize, making them attractive to small farmers in semi-arid tropics. Both cowpea and pigeonpea were affected by pests and diseases, which indicated the need for integrated pest management for realising the potential benefits of these legume-based systems.
Grain crop response to contour hedgerow systems on sloping Oxisols
Farming systems that minimize the rate of soil degradation and optimize food crop yields are needed to sustain soil productivity on sloping, acid, infertile soils in the humid tropics. Research was conducted on two Oxisols with slopes ranging from 22 to 30% to evaluate the performance of several contour hedgerow systems, with and without the addition of 60 kg N ha1 per crop, on rice (Oryza sativa) and maize (Zea mays L.) production. Contour hedgerows were double rows of the tree legume Gliricidia sepium (G); Gliricidia and the native grass Paspalum conjugatum (GPas); Gliricidia and an exotic fodder grass Penisetum purpureum (GPen); double rows of Penisetum (Pen); and a conventional open field (C) farming system without hedgerows. Gliricidia prunings and all crop residues were applied to the soil surface in the alleys, but Penisetum was harvested. Food crop yields in all hedgerow treatments tended to be less than the Control for the first two years, presumably due to the displacement of land planted to the food crop. In the third and the fourth years, the rice and maize yields of Treatments G and GPas exceeded the Control, most consistently when N was not applied. Penisetum reduced food crop yields regardless of N application presumably due to nutrient removal in the fodder. The results indicate that Gliricidia in a contour hedgerow increases food crop yield on strongly acid Oxisols by recycling nutrients and partially supplementing the N demand by the food crops
Agrosilvicultural systems: an alternative for the integrated management of mountainous terrain in Cuba.
The paper presents some Cuban experience on the research and development of agroforestry systems under mountainous conditions. The results obtained indicate that food fodder and wood can be realised on terraces of gradients between 5 and 40 percent. The livestock component indicated the posibility of utilizing the pastures that develop as the forest component is established.
Impact of Gliricidia sepium intercropping on soil organic matter fractions in a maize-based cropping system
The gliricidia (Gliricidia sepium)/maize intercropping system holds promise for increasing productivity in maize-based cropping systems on depleted soils in Southern Africa. The effect of the intercrop on soil properties was investigated to better understand soil processes underlying maize yield response, soil nutrient recapitalization and soil carbon sequestration. Soil organic matter (SOM) fractions, particulate organic matter (POM), POM-carbon, POM-nitrogen, soil nutrient status and underlying soil characteristics were quantified on the 14th year of a gliricidia/maize intercrop establish in 1991 on a Ferric Lixisol in southern Malawi. A factorial design compared the intercrop and a sole maize crop at three rates of added inorganic nitrogen (N) and phosphorus (P). Gliricidia leaf biomass was incorporated into the maize three times per year. Soil was sampled to a 20 cm depth, post-harvest to analyze biophysical and chemical characteristics of soil organic matter, POM, POM-C and POM-N, as well as inorganic N, available P, exchangeable K+ and particle size distribution. The gliricidia/maize intercrop had a significant and positive effect on SOM, POM, and SOM fractions: SOM was 12% higher, POM 40%, POM-C 62%, and POM-N 86% higher in the gliricidia intercrop compared to sole maize, indicating nitrogen enrichment of POM. Nitrogen fertilizer was associated with modest increases in POM, 15% in gliricidia and 27% in sole maize. The impacts of these changes were directed mostly at increasing maize yields and increasing storage of soil nutrients over the short term, while decreasing the proportion of organic matter stored over the long term. Both the gliricidia/maize intercrop and increasing soil clay content were associated with significantly increased soil CEC. The gliricidia intercrop maintained CEC in coarse-textured soils over a 14-year time span, indicating a role for legume trees in intensified cropping of coarse-textured soils.
Quantifying biological nitrogen fixation of agroforestry shrub species using 15N dilution techniques under greenhouse conditions
Some land-use systems in Saskatchewan, Canada include the nitrogen-fixing trees buffaloberry (Shepherdia argentea Nutt.), caragana (Caragana arborescens Lam.) and sea buckthorn (Hippophae rhamnoides L.). These species provide various ecological functions such as ameliorating soil moisture, light and temperature but little work has been done quantifying biological nitrogen fixation by these species. Greenhouse experiments were conducted to quantify N2-fixation using the 15N natural abundance and the 15N dilution methods. Buffaloberry failed to form nodules in all but one of the four replicates in the natural abundance experiment. Using the 15N dilution method, the percentage of N derived from atmosphere (%Ndfa) in the shoot of buffaloberry averaged 64 %. For caragana, the mean %Ndfa was 59 and 65 % and seabuckthorn was 70 and 73 % measured using the natural abundance and dilution methods, respectively. Because of large variability in biomass production between plants grown in the natural abundance experiment and the dilution experiment, the amounts of N2 fixed also were very variable. Buffaloberry fixed an average of 0.89 g N m-2; the average for caragana ranged from 1.14 to 4.12 g N m-2 and seabuckthorn ranged from 0.85 to 3.77 g N m-2 in the natural abundance and dilution experiments, respectively. This corresponds to 16 kg N ha-1 year-1 for buffaloberry; an average of 15-73 kg N ha-1 year-1 in caragana and 11-67 kg N ha-1 year-1 in seabuckthorn. The substantial amounts of N2 fixed by these species indicate that they have the potential to contribute to the overall N balance in land-use systems in which they are included