What role can planted fallows play in the humid and subhumid zone of West and Central Africa?

Crop management without fertilizer input, which is commonly practiced by most farmers in the humid forest zone of West and Central Africa, requires soil fertility replenishment during a fallow period. Hypothetical relationships between fallow length and crop yields assume, that after the cropping ph...

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Main Authors: Hauser, S., Nolte, C., Carsky, R.J.
Format: Journal Article
Language:Inglés
Published: Springer 2007
Subjects:
Online Access:https://hdl.handle.net/10568/91784
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author Hauser, S.
Nolte, C.
Carsky, R.J.
author_browse Carsky, R.J.
Hauser, S.
Nolte, C.
author_facet Hauser, S.
Nolte, C.
Carsky, R.J.
author_sort Hauser, S.
collection Repository of Agricultural Research Outputs (CGSpace)
description Crop management without fertilizer input, which is commonly practiced by most farmers in the humid forest zone of West and Central Africa, requires soil fertility replenishment during a fallow period. Hypothetical relationships between fallow length and crop yields assume, that after the cropping phase replenishment starts with high annual increments, leading to an early recovery of most soil fertility, then slowly approaching a maximum level. The few available empirical data, however, indicate that this assumption is wrong. Within the first 8 years of fallow, biomass and nutrient accumulation is either progressive (low initial increments) or linear. Planted fallows are supposed to replenish soil fertility faster or to higher levels than natural regrowth and should thus lead to higher crop yields. Two major types of planted fallow are distinguished: tree-based and herbaceous fallows. Data from West and Central Africa do not confirm that tree based fallows are generally capable of attaining higher crop yields than natural regrowth or other planted fallows. The majority of experiments with tree-based fallows showed no differences to the control (60.0%). Crop yield declines were found in 15.7% of cases, and only 24.3% resulted in significant yield increases. Changes in soil properties were more frequently positive (34.3%) than negative (9.8%), yet, most often (55.9%), there was no effect. Herbaceous fallow had dominantly positive effects on crop yields (52.5% of cases), with only 3% of cases in which significant reductions were observed. Positive features of some herbaceous fallows, such as easy establishment, rapid weed suppression, and labor efficient slash-and-burn crop establishment make the technology more likely to be accepted and adopted by farmers. It appears that fallows have to be specifically designed for responsive crops, i.e. maize. It is unlikely that one type of fallow can serve the multitude of crops and intercrops grown in the region. Depending on the major constraints to crop production or income generation, planted fallows have to be specifically designed to address these constraints. This may require de-emphasizing the soil fertility aspect and focusing on marketable fallow by-products, weed and pest suppression and reduced labor requirements. Thus, future impact through research on planted fallows will depend on exact targeting of specific fallow types and species to the most responsive crops and to explicit farmer circumstances.
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spelling CGSpace917842024-05-15T05:12:14Z What role can planted fallows play in the humid and subhumid zone of West and Central Africa? Hauser, S. Nolte, C. Carsky, R.J. crop yield response herbaceous leguminous fallow soil fertility replenishment tree-based Crop management without fertilizer input, which is commonly practiced by most farmers in the humid forest zone of West and Central Africa, requires soil fertility replenishment during a fallow period. Hypothetical relationships between fallow length and crop yields assume, that after the cropping phase replenishment starts with high annual increments, leading to an early recovery of most soil fertility, then slowly approaching a maximum level. The few available empirical data, however, indicate that this assumption is wrong. Within the first 8 years of fallow, biomass and nutrient accumulation is either progressive (low initial increments) or linear. Planted fallows are supposed to replenish soil fertility faster or to higher levels than natural regrowth and should thus lead to higher crop yields. Two major types of planted fallow are distinguished: tree-based and herbaceous fallows. Data from West and Central Africa do not confirm that tree based fallows are generally capable of attaining higher crop yields than natural regrowth or other planted fallows. The majority of experiments with tree-based fallows showed no differences to the control (60.0%). Crop yield declines were found in 15.7% of cases, and only 24.3% resulted in significant yield increases. Changes in soil properties were more frequently positive (34.3%) than negative (9.8%), yet, most often (55.9%), there was no effect. Herbaceous fallow had dominantly positive effects on crop yields (52.5% of cases), with only 3% of cases in which significant reductions were observed. Positive features of some herbaceous fallows, such as easy establishment, rapid weed suppression, and labor efficient slash-and-burn crop establishment make the technology more likely to be accepted and adopted by farmers. It appears that fallows have to be specifically designed for responsive crops, i.e. maize. It is unlikely that one type of fallow can serve the multitude of crops and intercrops grown in the region. Depending on the major constraints to crop production or income generation, planted fallows have to be specifically designed to address these constraints. This may require de-emphasizing the soil fertility aspect and focusing on marketable fallow by-products, weed and pest suppression and reduced labor requirements. Thus, future impact through research on planted fallows will depend on exact targeting of specific fallow types and species to the most responsive crops and to explicit farmer circumstances. 2007-02-20 2018-03-23T06:48:45Z 2018-03-23T06:48:45Z Journal Article https://hdl.handle.net/10568/91784 en Limited Access Springer Hauser, S., Nolte, C. & Carsky, R.J. (2006). What role can planted fallows play in the humid and sub-humid zone of West and Central Africa?. Nutrient Cycling in Agroecosystems, 76(2-3), 297-318.
spellingShingle crop yield response
herbaceous
leguminous fallow
soil fertility replenishment
tree-based
Hauser, S.
Nolte, C.
Carsky, R.J.
What role can planted fallows play in the humid and subhumid zone of West and Central Africa?
title What role can planted fallows play in the humid and subhumid zone of West and Central Africa?
title_full What role can planted fallows play in the humid and subhumid zone of West and Central Africa?
title_fullStr What role can planted fallows play in the humid and subhumid zone of West and Central Africa?
title_full_unstemmed What role can planted fallows play in the humid and subhumid zone of West and Central Africa?
title_short What role can planted fallows play in the humid and subhumid zone of West and Central Africa?
title_sort what role can planted fallows play in the humid and subhumid zone of west and central africa
topic crop yield response
herbaceous
leguminous fallow
soil fertility replenishment
tree-based
url https://hdl.handle.net/10568/91784
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