TY - JOUR T1 - Effects of trees on paddy bund on soil fertility and rice growth in Northeast Thailand JF - Agroforestry Systems Y1 - 1992 A1 - S. Sae-Lee A1 - P. Vityakon A1 - B. Prachaiyo KW - minerals KW - northeast Thailand KW - paddy KW - rice KW - soil fertility KW - trees AB -

A study was conducted in Northeast Thailand on six rice paddy fields on a farm with similar soil (Aquic Quartzipsamments) and with a single tree on the paddy bund. There were 4 tree species: Parinarium anamense, Dipterocarpus obtusifolius, D. intricatus, and Samanea saman. Samples of soil (0-10 cm depth) and rice were collected at 3 positions (1, 5-7, and 9-11 m) away from the tree base in 3 replicated tree-soil trasects in each paddy field. Significantly higher pH, organic matter, and nutrients (N, P, K, Ca, and Mg) were found in paddy fields with S. saman (a legume tree) but grain yield and biomass of rice were significantly lower. Higher soil fertility was found in the positions closer to tree base while grain yields, biomass, and number of tillers were lower, and rice was taller and had more unfilled grain. Shading was deduced to be the key factor responsible for the depressed rice yields and growth at positions closer to tree base especially in the highly shading S. saman.

VL - 18 UR - https://doi.org/10.1007/BF00123318 IS - 3 U1 - Agroforest Syst ER - TY - JOUR T1 - For a determined farmer, agroforestry brings an unexpected reward JF - Agroforestry Today (Kenya) Y1 - 1991 A1 - Sidney B. Westley A1 - Alice Kaudia KW - agroforestry KW - fodder KW - fuelwood KW - KEFRI KW - Kenya Forestry Research Institute KW - soil fertility KW - timber KW - trees KW - water AB - This document looks at the agroforestry efforts of George Nti'Gitonga, a farmer in Kenya's Meru District. Since 1967, Mr. Nti'Gitonga has established over 25,000 trees on his farm which he uses as fodder, food, fuelwood, timber, windbreaks, boundary plantings, erosion control, and maintenance of soil fertility. Also included in this document are Mr. Nti'Gitonga's method for growing his trees in the semi-arid environment, and how he plans on harvesting water for the trees. VL - 3 IS - 3 U1 - Agroforestry Today (Kenya) ER - TY - JOUR T1 - Soil fertility management of paddy fields by traditional farmers in the dry zone of Sri Lanka JF - Journal of Sustainable Agriculture Y1 - 1991 A1 - Rohana Ulluwishewa KW - aquaculture KW - soil fertility KW - Sri Lanka AB - Traditional farmers in the Dry Zone of Sri Lanka maintained soil fertility of paddy fields for centuries without applying mineral fertilizers. Some of their traditional cultivation practices not only preserved the natural processes which lead to the regeneration of fertility, but also added nutrients to the soil. This study highlights those traditional practices-fallow period, application of green manure and animal waste, aquaculture in paddy fields, utilization of nutrients in irrigation water and planting trees on paddy fields. Why these practices ceased to exist with the introduction of agricultural modernization and increased population is examined herewith. VL - 1 UR - http://www.tandfonline.com/doi/abs/10.1300/J064v01n03_08 IS - 3 ER - TY - JOUR T1 - Land-use by immigrant Baoulé farmers in the Taï region, South-west Côte d'Ivoire (Ivory Coast) JF - Agroforestry Systems Y1 - 1990 A1 - Arnoud Budelman A1 - Peter M. Zander KW - agriculture KW - cacao KW - Humid Côte d'Ivoire KW - Ivory Coast KW - land shortage KW - soil fertility KW - transition shifting cultivation KW - yams AB -

This paper discusses the cropping system of immigrant Baoulé farmers in the rain-forest area of South-west Côte d'Ivoire (Ivory Coast). The area harbours one of the last substantial rain-forest reserves of humid West Africa. Part of it is known as Taï National Park, and has been adopted as one of UNESCO's Man and Biosphere Programme areas. The park area is threatened by farmers in search of land. Soils in the area typically show a low intrinsic nutrient content (particularly phosphorus and potassium), low pH values, a low CEC, and, locally, high levels of gravel. In the Baoulé cropping system fields are kept under perennial crops, mainly cacao, after having been used for food crop cultivation during the first two years. Yam, the most important food crop is grown on mounds. Next to the inherent poverty of the soil, this cropping technique, which disrupts the structure of the top soil is seen as one of the causes for low yields of cocoa on Baoulé farms in the area. Yields per ha amount to c. 60% of that of the national average. The conclusion is that the Baoulé agricultural production system is ill-adapted to the local ecosystem. Measures to improve adaptation include: Introduction of crop species adapted to adverse soil conditions (e.g. rubber, oilpalm), to buffer cacao plantations through planting of shade trees, to apply fertilisers, and to make use of biological nitrogen-fixation. Generally, the remedies proposed involve investments in terms of cash and labour on the part of the farmers. It is argued that farmers will not change their current cropping practices as long as there is forested land in the vicinity. The presence of the Taï forest, c. 300.000 ha of virgin rain-forest, impedes the process of change towards more intensive land-use practices.

VL - 11 UR - http://link.springer.com/article/10.1007/BF00838724 IS - 2 U1 - Agroforest Syst ER - TY - JOUR T1 - Structure and function of traditional agroforestry systems in the western Himalaya. II. Nutrient cycling JF - Agroforestry Systems Y1 - 1989 A1 - Om Parkash Toky A1 - Pradeep Kumar A1 - Prem Kumar Khosla KW - agroforestry systems KW - allocation pattern KW - nutrient budget KW - nutrient cycling KW - soil fertility KW - Western Himalaya AB - Budget of nutrient in plant and soil, and their rates of recycling in three types of traditional agroforestry systems in mid elevations of the western Himalaya were studied. Concentration of nitrogen and potassium was significantly higher in fruits and leaves than in branches, boles, and litter. Grewia optiva, an important fodder tree, was found to be rich in potassium, vegetable crops in nitrogen, and weeds in phosphorus. Maximum store of nutrients was estimated in aboveground biomass of agrihortisilvicultural system: nitrogen 532, phosphorus 40, potassium 461, calcium 400, and magnesium 298 kg/ha; it was closely followed by that in agrihorticultural system, and both these had about 2-fold higher nutrient stock as compared to agrisilvicultural system. In the case of the former two systems, considerable quantity of nutrients up to nitrogen 169, phosphorus 14, potassium 165, calcium 97, and magnesium 65 kg/ha, for example in agrihortisilvicultural system, was recycled through debris of crops and weeds, and tree leaf litter, while the recycling rate was almost half in agrisilvicultural system. Through 'harvest' potassium was depleted in the largest quantity from the system, followed by nitrogen, magnesium, calcium, and phosphorus; much higher loss occurred through agricultural and/or horticultural edible parts as compared to fuel and fodder biomass. For example, the loss through agricultural crops and horticultural fruits for nitrogen in agrihortisilvicultural system was up to 75 percent and 38 percent respectively of the total annual uptake. This heavy loss makes the system unstable from a nutrient point of view particularly for nitrogen and potassium until external inputs are added through organic and inorganic fertilizers. Agrihortisilvicultural system is remarkably efficient in view of biomass productivity for fuel, fodder and fruits, and also from nutrient point of view provided losses through harvest are compensated externally. VL - 9 UR - https://doi.org/10.1007/BF00120156 IS - 1 U1 - Agroforest Syst ER - TY - CHAP T1 - Elements of success: Sustainable development in sub-Saharan Africa T2 - World Resources 1987: An assessment of the resource base that supports the global economy Y1 - 1987 A1 - International Institute for the Environment and Development (IIED) A1 - World Resourses Institute (WRI) KW - agroforestry KW - alley cropping KW - Burkina Faso KW - cassava KW - charcoal KW - drought KW - fuelwood KW - green revolution KW - Kenya KW - maize KW - Niger KW - Nigeria KW - OXFAM KW - rainfall KW - reforestation KW - soil fertility KW - stoves KW - trypanosomiasis KW - water conservation KW - windbreaks KW - Zimbabwe AB - In recent years, Africa's farmers and herders, its soils and forests, have been chasing each other down a vicious spiral of environmental degradation and deepening poverty. Conventional development efforts by donors and governments have largely failed to halt the spiral, indeed in some cases have aggravated it. The need to find solutions is urgent. Africa not only must increase its energy and found output in line with rapidly expanding populations, but must do so in a way that preserves the resource base and enhances the welfare and income of the majority. Despite the general landscape of failure, a growing number of projects and programs -- governmental, intergovernmental, and nongovernmental -- have succeeded. This chapter examines some of those "success stories" and attempts to draw some more general lessons that can point to a "recipe for success" in sub-Saharan Africa. JF - World Resources 1987: An assessment of the resource base that supports the global economy PB - Basic Books CY - Washington, DC SN - 0-465-09239-X UR - https://www.wri.org/publication/world-resources-1987 N1 - Chapter 14 U5 - 18 pp. JO - Elements of success ER - TY - BOOK T1 - Man and tree in tropical Africa: Three essays on the role of trees in the African environment Y1 - 1978 A1 - Gunnar Poulsen KW - agroforestry KW - erosion control KW - fuelwood KW - soil erosion KW - soil fertility AB -

Contains following essays:

The first paper examines, in general, the role of the tree in tropical Africa. Highlighted are the variety of products that can be obtained from the forests, the vital role of trees in nutrient cycling and in soil and water conservation, and their influence on both micro and macroclimate. The second essay addresses the ever important question of wood-fuel supplies. With increasing petroleum prices, greater demands than ever before are being placed on wood, and with decreasing supplies prices are rising. Wood-fuel shortages have led to a switch to other fuel sources such as manure and crop residues, which has in turn started a vicious circle of decreasing crop yields and environmental degradation. The final essay examines the age-old practice of shifting cultivation. Suggestions advanced here for tailoring new ideas to this traditional practice may well make it possible to modify or improve the system to meet modern realities. Methods involving zero tillage and the use of trees as 'nutrient pumps' seem to offer particular promise in this regard.

PB - International Development Research Centre CY - Ottawa, ON, Canada SN - 0-88936-154-1; 978-0-88936-154-6 UR - http://www.worldcat.org/oclc/5510947 JO - Man and tree in tropical Africa ER -