The potential of agroforestry for sustainable land and water management

doi:10.1017/CBO9780511535666.033

26 - The potential of agroforestry for sustainable land and water management

from Part III - Forest disturbance, conversion and recovery

Published online by Cambridge University Press: 12 January 2010

J. S. Wallace ,

A. Young and

C. K. Ong

Edited by

M. Bonell and

L. A. Bruijnzeel

Show author details

J. S. Wallace: Affiliation:
CSIRO Land and Water, Townsville, QLD 4811, Australia
A. Young: Affiliation:
School of Environmental Sciences, University of East Anglia, Norwich, NR4 7TJ, UK
C. K. Ong: Affiliation:
Regional Land Management Unit, RELMA, International Centre for Research in Agroforestry, Nairobi, Kenya
M. Bonell: Affiliation:
UNESCO, Paris
L. A. Bruijnzeel: Affiliation:
Vrije Universiteit, Amsterdam

Book contents

Get access

Summary

INTRODUCTION

Improving the efficiency of land and water resource use

Much of the future increase in food and wood production in the humid tropics (and elsewhere), necessary to meet the needs of increasing populations and to reduce hunger and poverty, will have to be achieved from land and water resources already in use. Field observation shows that the extent of the ‘land balance’ – land that could be used for productive purposes but is not currently in use – is very limited. Estimates by FAO and associated organisations appear to show substantial areas which are cultivable but not presently cultivated (Alexandratos, 1995; Bot et al., 2000). However, the validity of these estimates has recently been challenged, suggesting that the ‘land balance’ may be 50% or less of that in the official estimates (Young, 1998; 2000). Moreover, a large proportion of the ‘land balance’ is under forest, for example in Brazil, Congo Democratic Republic (formerly Zaire), Indonesia, Peru and Venezuela, clearance of which is strongly opposed for reasons of environment and biodiversity (Alexandratos, 1995).

The above ‘land balance’ issue focuses the associated research agenda on the challenge of improving the efficiency with which existing land and water resources are used. Over the past half-century, great progress has been achieved in this respect. In agriculture, this has been through the advances generally referred to as the green revolution; in forestry, it has been brought about through a variety of improvements in forest management systems, including fast-growing, high-yielding plantations, and by means of genetic improvement.

Information

Type: Chapter
Information: Forests, Water and People in the Humid Tropics
Past, Present and Future Hydrological Research for Integrated Land and Water Management
, pp. 652 - 670

DOI: https://doi.org/10.1017/CBO9780511535666.033 [Opens in a new window]

Publisher: Cambridge University Press

Print publication year: 2005

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

Book purchase

Temporarily unavailable

References

Alexandratos, N. (1995) World agriculture: towards 2010. An FAO study. Chichester, UK: Wiley, for FAO

Azam-Ali, S. N. (1983) Seasonal estimates of transpiration from a millet crop using a porometer. Agricultural and Forest Meteorology 30: 13–24CrossRef Google Scholar

Baillie, I. C., (1989) Soil characteristics and classification in relation to the mineral nutrition of of tropical wooded ecosystems. In Proctor (1989, q.v.), 15–26Google Scholar

Banda, A. Z., Maghembe, J. A., Ngugi, D. N., and Chome, V. A. (1994) Effect of intercropping maize and closely spaced Leucaena hedgerows on soil conservation and maize yield on a steep slope at Ntcheu, Malawi. Agroforestry Systems 27, 17–22CrossRef Google Scholar

Beer, J. (1987) Advantages, disadvantages and desirable characteristics of shade trees for coffee, cacao and tea. Agroforestry Systems 5, 3–13CrossRef Google Scholar

Beer, J., Bonnemann, A., Chavez, W., et al. (1990) Modelling agroforestry systems of cacao (Theobroma cacao) with laurel (Cordia alliodora) or poro (Erythrina poeppigiana) in Costa Rica. V. Productivity indices, organic material models and sustainability over 10 years. Agroforestry Systems 12, 229–249CrossRef Google Scholar

Belsky, A. J. and Amundson, R. G. (1997) Influence of savannah trees and shrubs on understorey grasses and soils: new directions in research. In: Carbon and Nutrient Dynamics in Natural and Agricultural Tropical Ecosystems (Eds. Bergstrom, L. and Kirchmann, H.) pp 153–171, CAB International, Wallingford, UK

Bot, A. J., Nachtergaele, F. O. and Young, A. (2000) Land resource potential and constraints at regional and country levels. World Soil Resources Report 90. Rome: FAO

Bowen, G. D., Sanginga, N., and Danso, S. K. A. (1990) Biological nitrogen fixation in agroforestry – an overview. Transactions of the 14th International Congress of Soil Science, 3, 170–175Google Scholar

Brenner, A. J., 1996. Micro-climatic modifications in Agroforestry. In: Tree-crop interactions – a physiological approach (Eds. Ong, C. K., and Huxley, P. A.) CAB International, Wallingford, UK, pp 159–187

Bruijnzeel, L. A. (1989) Nutrient cycling in moist tropical forests: the hydrological framework. In Proctor (1989, q.v.), 383–415Google Scholar

Bruijnzeel, L. A. (1991) Nutrient input-output budgets of tropical forest ecosystems. Journal of Tropical Ecology 7, 1–24CrossRef

Buresh, R. J. and Cooper, P. J. M. (eds.) 1999. The science and practice of short-term improved fallows. Agroforestry Systems 47, 1–358CrossRef Google Scholar

Buresh, R. J. and Tian, G. (1997) Soil improvement by trees in sub-Saharan Africa. Agroforestry Systems 38, 51–76CrossRef Google Scholar

Burgess, S. S. O., Adams, M. A., Turner, N. C. and Ong, C. K. (1998) Redistribution of water within plant root systems. Oceologia 115, 306–311CrossRef Google Scholar

Cadish, G. and Giller, K. R. (eds.) (1996) Driven by nature: plant litter quality and decomposition. Wallingford, UK: CAB International

Calder, I. R. and Newson, M. D. 1979. Land-use and upland water resources in Britain-a strategic look. Water Resources Bulletin, 15, 1628–1639CrossRef Google Scholar

Cannell, M. G. R., Noordwijk, M. and Ong, C. K. (1996) The central agroforestry hypothesis: the trees must acquire resources that the crop would not otherwise acquire. Agroforestry Systems, 34, 27–31CrossRef Google Scholar

Cooper, P. J. M., Leakey, R. R. B., Rao, M. R., and Reynolds, L. (1996) Agroforestry and the mitigation of land degradation in the humid and sub-humid tropics of Africa. Experimental Agriculture 32, 235–290CrossRef Google Scholar

Corlett, J. E., Black, C. R., Ong, C. K. and Monteith, J. L. (1992a) Above and below-ground interactions in a leucaena/millet alley cropping system. 2. Light interception and dry matter production. Agricultural and Forest Meteorology 60, 73–91CrossRef Google Scholar

Corlett, J. E., Ong, C. K., Black, C. R. and Monteith, J. L. (1992b) Above and below-ground interactions in a leucaena/millet alley cropping system. 1. Experimental design, instrumentation and diurnal trends. Agricultural and Forest Meteorology 60, 53–72CrossRef Google Scholar

Culf, A. D., Allen, S. J., Gash, J. H. C., Lloyd, C. R. and Wallace, J. S. (1993) Energy and water budgets of an area of patterned woodland in the Sahel. Agricultural and Forest Meteorology 66, 65–80CrossRef Google Scholar

Danso, S. K. A., Bowen, G. D. and Sanginga, N. (1992) Biological nitrogen fixation in trees in agro-ecosystems. Plant and Soil 141, 177–196CrossRef Google Scholar

Dawson, T. E. (1993) Hydraulic lift and water use by plants: implications for water balance, performance and plant-plant interactions. Oceologia 95, 565–574CrossRef Google Scholar PubMed

Wit, C. (1960) On competition. Verslagen van Landbouwkunige Onderzoekingen 66, 1–82Google Scholar

Ewel, J. J. (1986) Designing agricultural ecosystems for the humid tropics. Ann Rev Ecol and Syst, 17, 245–271CrossRef Google Scholar

Fujisaka, S. (1993) A case of farmer adaptation and adoption of contour hedgerows for soil conservation. Experimental Agriculture 29, 97–105CrossRef Google Scholar

Fukai, S. and Trenbath, B. R. (1993) Processes involving intercrop productivity and yields of component crops. Field Crops Res 34, 247–271CrossRef Google Scholar

Garrity, D. P. (1996) Tree-crop-soil interactions on slopes. In Tree-crop interactions: a physiological approach (ed. C. K. Ong and P. Huxley, CAB International, Wallingford, UK), 299–318

Gash, J. H. C., Lloyd, C. R. and Lachaud, G. (1995) Estimating sparse forest rainfall interception with an analytical model. Journal of Hydrology, 170, 79–86CrossRef Google Scholar

Gregory, P. J. (1996) Approaches to modelling the uptake of water and nutrients in agroforestry systems. Agroforestry Systems 34, 51–65CrossRef Google Scholar

Golley, F. B., McGinnis, J. T., Clements, R. G., Child, G. I. and Duever, M. J. (1975). Mineral cycling in a tropical moist forest ecosystem. University Georgia Press, Athens. 248 pp

Hopkins, B. (1960) Rainfall interception by a tropical rainforest in Uganda. East African Agricultural Journal 25, 255–258CrossRef Google Scholar

Howard, S. B., Ong, C. K., Black, C. R. and Khan, A. A. H. (1997) Using sap flow gauges to quantify water uptake by tree roots from beneath the crop rooting zone in agroforestry systems. Agroforestry Systems 35, 15–29CrossRef Google Scholar

Hudson, N. W. (1995) Soil conservation. Batsford, London

Huntley, B. J. and Walker, B. H. (ed) (1982) Ecology of Tropical Savannas. Springer Verlag, Berlin, pp 669CrossRef

ICRAF (1993) International Centre for Research in Agroforestry. Annual Report 1993. Nairobi: ICRAF

Imbach, A. C., Fassbender, H. W., Borel, R., Beer, J. and Bonnemann, A. (1989) Modelling agroforestry systems of cacao (Theobroma cacao) with laurel (Cordia alliodora) and cacao with poro (Erthrina poeppigiana) in Costa Rica IV. Water balances. Agroforestry Systems 8, 267–287CrossRef Google Scholar

Jackson, N. A. and Wallace, J. S. (1999) Soil evaporation measurements in an agroforestry system in Kenya. Agricultural and Forest Meteorology 94, 203–215CrossRef Google Scholar

Jackson, N. A. (2000) Measured and modelled rainfall interception loss from an agroforestry system in Kenya. Agricultural and Forest Meteorology 100, 323–336CrossRef Google Scholar

Jackson, N. A., Wallace, J. S. and Ong, C. K. (2000) Tree pruning as a means of controlling water use in an agroforestry system in Kenya. Forest Ecology and Management 126, 133–148CrossRef Google Scholar

Jonsson, K., Fidgeland, L., Maghembe, J. A. and Hogberg, P. (1988) The vertical root distribution of fine roots of five tree species and maize in Morogoro, Tanzania. Agroforestry Systems 6, 63–69CrossRef Google Scholar

Jordan, C. F., Gajeseni, J. and Watanabe, H. (eds.) (1992) Taungya: forest plantations in South East Asia. Wallingford, UK: CAB International

Kater, L. J. M., Kante, S. and Budelman, A. (1992) Karite (Vitellaria paradoxa) and nere (Parkia biglobosa) associated with crops in South Mali. Agroforestry Systems 18, 89–105CrossRef Google Scholar

Keipe, P. and Rao, M. R. (1994) Management of agroforestry for the conservation and utilization of land and water resources. Outlook on Agriculture 23, 17–25CrossRef Google Scholar

Kiepe, P. (1995a) No runoff, no soil loss: soil and water conservation in hedgerow barrier systems. Tropical Resource Management Papers 10. Wageningen, Netherlands: Agricultural University

Kiepe, P. (1995b) Effect of Cassia siamea hedgerow barriers on soil physical properties. Geoderma 66, 113–120CrossRef Google Scholar

Khan, A. A. H. and Ong, C. K. (1996) A low cost heat pulse method for measuring tree root water uptake. Agroforestry For 7(2):19–22Google Scholar

Kuusipalo, J., Adjers, G., Jafarsidik, Y.. (1995) Restoration of natural vegetation in degraded Imperata cylindrical grassland: understorey development in forest plantations. Journal of Vegetation Science 6, 205–210CrossRef Google Scholar

Kwesiga, F. and Coe, R. (1994) The effect of short rotation Sesbania sesban planted fallows on maize yield. Forestry Ecology and Management 64, 199–208CrossRef Google Scholar

Lal, R. (1991) Current research on crop water balance and implications for the future. In: Soil Water Balance in the Sudano-Sahelian Zone (Eds. M. V. K. Sivakumar, J. S. Wallace, C. Renard and C. Giroux) Proc. Int. Workshop, Niamey, Niger, February 1991) IAHS Publ. no. 199, 31–44. IAHS Press. Institute of Hydrology, Wallingford, UK

Lavelle, P., Spain, A. V., Blanchart, E., Martin, A. and Martin, S. (1992) The impact of soil fauna on the properties of soils in the humid tropics. In: Myths and Science of Soils of the Tropics. Soil Science Society of America Special Publication 29, 157–185Google Scholar

Lefroy, E. C. and Stirzaker, R. J. (1999) Agroforestry for water management in southern Australia. Agroforestry Systems 45, 277–302CrossRef Google Scholar

Lloyd, C. R., Gash, J. H. C., Shuttleworth, W. J. and Marques, F. A.de O. (1988) The measurement and modelling of rainfall interception by Amazonian rainforest. Agricultural and Forest Meteorology 43, 277–294CrossRef Google Scholar

Lott, J. E., Khan, A. A. H., Ong, C. K. and Black, C. K. (1996) Sap flow measurements of lateral roots in agroforestry systems. Tree Physiol 16, 995–1001CrossRef Google Scholar PubMed

McIntyre, B. D., Riha, S. J. and Ong, C. K. (1996) Light interception and evapotranspiration in hedgerow agroforestry systems. Agricultural and Forest Meteorology 81, 31–40CrossRef Google Scholar

Menz, K., Magcale-Macandog, D. and Rusastra, I. W. (eds.) (1999) Improving smallholder farming systems in Imperata areas of South East Asia: alternatives to shifting cultivation. ACIAR Monographs 52. ACIAR, Canberra

Monteith, J. L., (1986) How do crops manipulate water supply and demand?Phil Trans Roy Soc London, B., 316, 245–259CrossRef Google Scholar

Monteith, J. L., Ong, C. K. and Corlett, J. E. (1991) Microclimatic interactions in agroforestry systems. For Ecol Manage 45, 31–44CrossRef Google Scholar

Nair, P. K. R. (1984) Soil productivity aspects of agroforestry. Nairobi: ICRAF

Nair, P. K. R. (1989) Agroforestry systems in the tropics. Dordrecht, the Netherlands: Kluwer

Nortcliff, S. and Thornes, J. B. (1989) Variations in soil nutrients in relation to soil moisture status in a tropical forested ecosystem. In Mineral nutrients in tropical forest and savanna ecosystems (ed. J. Proctor, Blackwell, Oxford, UK), 43–54

Ong, C. K., Simmonds, L. P. and Matthews, R. B. (1987) Responses to saturation deficit in a stand of groundnut (Arachis hypogaea L.) 2. Growth and development. Ann Bot 59, 121–128CrossRef Google Scholar

Ong, C. K. and Black, C. R. (1994) Complementarity in resource use in intercropping and agroforestry systems. In: Resource Capture by Crops (Eds. Monteith J. L., Scott R. K. and Unsworth M. H.) Nottingham University Press, pp 255–278 Loughborough, UK

Ong, C. K., Black, C. R., Marshall, F. M., and Corlett, J. E., (1996) Principles of resources capture and utilisation of light and water. In: Tree-crop interactions – a physiological approach (Eds. Ong, C. K., and Huxley, P. A.) CAB International, Wallingford, UK, pp. 73–158

Ong, C. K. and Leakey, R. R. B. (1999) Why tree crop interactions in agroforestry appear at odds with tree-grass interactions in tropical savannahs. Agroforestry Systems 45, 109–129CrossRef Google Scholar

Ong, C. K., Deans, J. D., Wilson, J., Mutua, J., Khan, A. A. H. and Lawson, E. M. (1999) Exploring below ground complementarity in agroforestry using sap flow and root fractal techniques. Agroforestry Systems 44, 87–103Google Scholar

Ong, C. K., Black, C. R., Wallace, J. S., Khan, A. A. H., Lott, J. E., Jackson, N. A., Howard, S. B. and Smith, D. M. (2000) Productivity, microclimate and water use in Grevillea robusta based agroforestry systems on hillslopes in semi-arid Kenya. Agriculture, Ecosystems and Environment 80, 121–141CrossRef Google Scholar

Proctor, J. (ed.) (1989) Mineral nutrients in tropical forest and savanna ecosystems. Blackwell, Oxford

Queblatin, E. (1985) Upland agricultural development: the Central Visayas regional project-I experience. In Soil erosion management. ACIAR Proceedings Series 6 (Eds. Craswell, E. T., Remenyi, J. V. and Nallana, L. G, Canberra, ACIAR), 71–76

Rhoades, C. C. (1997) Single-tree influences on soil properties in agroforestry: lessons from natural forest and savanna ecosystems. Agroforestry Systems 35, 71–94CrossRef Google Scholar

Ritchie, J. T. (1972) Model for predicting evaporation from a row crop with incomplete cover. Water Resources Research 8, 1204–1213CrossRef Google Scholar

Rockstrom, J. (1997) On – farm agrohydrological analysis of the Sahelian yield crisis: rainfall partitioning, soil nutrients and water use efficiency of pearl millet. Ph. D thesis, University of Stockholm

Rose, C. W. and Freebairn, D. M. (1985) A new mathematical model of soil erosion and deposition processes with applications to field data. In Soil erosion and conservation (ed. S. A. El-Swaify, W. C. Moldenhauer, and A. Lo, Ankeny, Iowa, USA: Soil Conservation Society of North America), 549–557

Ross, S. M., Thornes, J. B., and Nortcliff, S. (1990) Soil hydrology, nutrient and erosional response to the clearance of terra firme forest, Maracá Island, Roraima, northern Brazil. Geographical Journal 156, 267–282CrossRef Google Scholar

Sajjapongse, A. and Leslie, R. N. (eds.) (1998) Farmers' acceptance of soil-conservation technologies. IBSRAM Proceedings 17. Bangkok: IBSRAM

Sanchez, P. (1995) Science in agroforestry. Agroforestry Systems 30, 5–55CrossRef Google Scholar

Sanginga, N., Lauwe, B., and Danso, S. K. A. (1995) Management of biological N2 fixation in alley cropping systems – estimation and contribution to N balance. Plant and Soil 174, 119–141CrossRef Google Scholar

Sinoquet, H. and Cruz, P. (1995) Ecophysiology of Tropical Intercropping. INRA. Paris. 483 pp

Schellekens, J., Scatena, F. N., Bruijnzeel, L. A. and Wickel, A. J. (1999) Modelling rainfall interception by a lowland tropical rainforest in northeastern Puerto Rico. Journal of Hydrology 225, 168–184CrossRef Google Scholar

Schroth, G., Ferreira da Silva, L., Wolf, M-A., Teixeira, W. G. and Zech, W. (1999) Distribution of throughfall and stemflow in multi-strata agroforestry, perennial monoculture, fallow and primary forest in central Amazonia, Brazil. Hydrological Processes 13, 1423–14363.0.CO;2-9>CrossRef Google Scholar

Shuttleworth, W. J. (1988) Evaporation from Amazonian rainforest. Proceedings of the Royal Society of London Series B, 233, 321–346CrossRef Google Scholar

Smith, D. M., Jarvis, P. G. and Odongo, J. C. W. (1997) Sources of water used by trees and millet in Sahelian windbreak systems. J Hydrol 198: 140–153CrossRef Google Scholar

Smith, D. M., Jackson, N. A., Roberts, J. M. and Ong, C. K. (1999a) Reverse flow in tree roots and downward siphoning of water by Grevillea robusta. Funct Ecol 13(2), 256–264CrossRef Google Scholar

Smith, D. M., Jackson, N. A., Roberts, J. M. and Ong, C. K., (1999b) Root distributions in a Grevillea robusta – maize agroforestry system in semi-arid Kenya. Plant and Soil 211, 191–205CrossRef Google Scholar

Squire, G. R., (1990) The Physiology of Tropical Crop Production. CAB International, Wallingford, UK

Stewart, M. and Bromley, T. (1994) Use of Melia volkensii in a semi-arid agroforestry systems in Kenya. Comm For Rev 73(2), 128–131Google Scholar

Stigter, C. J. (1984) Mulching as a traditional method of microclimate management. Arch Me Geophys Bioclim Ser B 35, 147–154CrossRef Google Scholar

Stoorvogel, J. J. and Smaling, E. M. A. (1990) Assessment of soil nutrient depletion in Sub-saharan Africa: 1983–2000. Staring Centre Report 28. Wageningen, the Netherlands: Staring Centre

Swift, M. J., Heal, J. W., and Anderson, J. M. (1979) Decomposition in terrestrial ecosystems. Oxford, UK: Blackwell

Teklehaimanot, Z. and Jarvis, P. G. (1991) Direct measurement of evaporation of intercepted water from forest canopies. Journal of Applied Ecology 28, 603–618CrossRef Google Scholar

Valente, F., David, J. S. and Gash, J. H. C. (1997) Modelling interception loss for two sparse eucalypt and pine forests in central Portugal using reformulated Rutter and Gash models. Journal of Hydrology 190, 141–162CrossRef Google Scholar

Dijk, A. I. J. M. and Bruijnzeel, L. A. (2001) Modelling rainfall interception by vegetation of variable density using an adapted analytical model. Part 1. Model description. Journal of Hydrology 247, 230–238CrossRef Google Scholar

Dijk, A. I. J. M. and Bruijnzeel, L. A. (2001) Modelling rainfall interception by vegetation of variable density using an adapted analytical model. Part 2. Model validation for a tropical upland mixed cropping system. Journal of Hydrology 247, 239–262CrossRef Google Scholar

Noordwijk, M. and Purnomosidhi, P. (1995) Root architecture in relation to tree-soil-crop interactions and shoot pruning in agroforestry. Agroforestry Systems 30, 161–173CrossRef Google Scholar

Noordwijk, M. and Ong, C. K. (1999) Can the ecosystem mimic hypotheses be applied to farms in African savannahs?Agroforestry Systems 45, 131–158CrossRef Google Scholar

Wallace, J. S. (1996) The water balance of mixed tree-crop systems. In: Tree-crop interactions – a physiological approach (Eds. Ong, C. K., and Huxley, P. A.) CAB International, Wallingford, UK, pp. 189–233

Wallace, J. S., Jackson, N. A. and Ong, C. K. (1995) Water balance of agroforestry systems on hillslopes – phase I. Final Report to the forestry Research Programme, UK Department for International Development pp 40, Centre for Ecology and Hydrology Wallingford

Wallace, J. S., Jackson, N. A., and Ong, C. K., (1999) Modelling soil evaporation in an agroforestry system in Kenya. Agricultural and Forest Meteorology 94, 189–202CrossRef Google Scholar

Wallace, J. S., and Verhoef, A., (2000) Modelling interactions in mixed-plant communities: light, water and carbon dioxide. In: Leaf Development and Canopy Growth (Eds. Marshall, B., and Roberts, J. A.) Sheffield Academic Press, Sheffield, pp 204–250

Whitmore, T. C. (1989) Tropical forest nutrients: where do we stand? A tour de horizon. In Proctor (1989, q.v.), 1–14Google Scholar

Wiersum, K. F. (1984) Surface erosion under various tropical agroforestry systems. In Symposium on effects of forest land use on erosion and slope stability (ed. C. L. O'Loughlin and Pearce, A. J., Honolulu, USA, East-West Center), 231–239

Wiersum, K. F. (1985) Effects of various vegetation layers in an Acacia auriculiformis forest plantation on surface erosion in Java, Indonesia. In Soil erosion and conservation (ed. S. A. El-Swaify, W. C. Moldenhauer, and A. Lo, Ankeny, Iowa, USA: Soil Conservation Society of North America), 79–89

Woomer, P. L. and Swift, M. J. (1994) The biological management of tropical soil fertility. Chichester, UK: Wiley

Yamoah, C. F., Agboola, A. A. and Mulongoy, K. (1986) Soil properties as affected by the use of leguminous shrubs for alley cropping with maize. Agriculture, Ecosystems and Environment 18, 167–177CrossRef Google Scholar

Young, A. (1989) Agroforestry for soil conservation. Nairobi: ICRAF, 276pp

Young, A. (1990) Agroforestry for the management of soil organic matter. In Organic-matter management and tillage in humid and subhumid Africa. IBSRAM Proceedings 10 (ed. E. Pushparajah, M. Latham and C. R. Elliott, IBSRAM, Bangkok), 285–303

Young, A. (1993) Agroforestry as a viable alternative for soil conservation. Entwicklung und Ländlicher Raum 27(5), 3–7Google Scholar

Young, A. (1997a) Agroforestry for soil management. Wallingford, UK: CAB International

Young, A. (1997b) The effectiveness of contour hedgerows for soil and water conservation. Agroforestry Forum 8(4), 2–4Google Scholar

Young, A. (1998) Land resources: now and for the future. Cambridge, UK: Cambridge University Press

Young, A. (2000/2001) How much spare land exists?Bulletin of the International Union of Soil Sciences 97, 51–55Google Scholar

Young, A., Menz, K., Muraya, P. and Smith, C. (1998) SCUAF Version 4. A model to estimate soil changes under agriculture, agroforestry and forestry. ACIAR Technical Reports 41. Canberra: ACIAR

Accessibility standard: Unknown

Why this information is here

This section outlines the accessibility features of this content - including support for screen readers, full keyboard navigation and high-contrast display options. This may not be relevant for you.

Accessibility Information

Accessibility compliance for the PDF of this chapter is currently unknown and may be updated in the future.