TY - JOUR
T1 - Research on soil fertility decline in tropical environments: Integration of spatial scales
AU - Stoorvogel, J.J.
AU - Smaling, E.M.A.
PY - 1998
Y1 - 1998
N2 - Soil nutrient depletion is increasingly regarded as a major constraint to sustainable food production in tropical environments. Research in the recent past focused on different scales, but few attempts were made to link them. In this paper, two cases are elaborated in Central America (CA) and Sub-Saharan Africa (SSA), in which the integration of different scales has been studied. Soil nutrient depletion has been calculated for fields, and has then been aggregated to farms, regions, and subcontinents. Key problems on aggregation of field nutrient balances to farms include nutrient flows between fields. Aggregation of farms to regions requires a generalization of individual farms into a farm typology. Aggregation of regions into subcontinents implies that the farm typology concept can mostly not be maintained, resulting in a generalized calculation based on national soil, climate and land use data bases. The field-farm step proved complicated for SSA due to the occurrence of a wide variety of nutrient flows between fields, whereas in CA these flows were much less pronounced; the farm-region step turned out to be manageable for both CA and SSA as farm typology adequately covered observed variation; the region-subcontinent step proved difficult for CA due to the considerable variation in management and input levels in farming systems, whereas this was less the case in SSA. The study shows that integration of spatial scales is constrained by both data availability (the tropical parameter crisis) and by scale-specific variability.
AB - Soil nutrient depletion is increasingly regarded as a major constraint to sustainable food production in tropical environments. Research in the recent past focused on different scales, but few attempts were made to link them. In this paper, two cases are elaborated in Central America (CA) and Sub-Saharan Africa (SSA), in which the integration of different scales has been studied. Soil nutrient depletion has been calculated for fields, and has then been aggregated to farms, regions, and subcontinents. Key problems on aggregation of field nutrient balances to farms include nutrient flows between fields. Aggregation of farms to regions requires a generalization of individual farms into a farm typology. Aggregation of regions into subcontinents implies that the farm typology concept can mostly not be maintained, resulting in a generalized calculation based on national soil, climate and land use data bases. The field-farm step proved complicated for SSA due to the occurrence of a wide variety of nutrient flows between fields, whereas in CA these flows were much less pronounced; the farm-region step turned out to be manageable for both CA and SSA as farm typology adequately covered observed variation; the region-subcontinent step proved difficult for CA due to the considerable variation in management and input levels in farming systems, whereas this was less the case in SSA. The study shows that integration of spatial scales is constrained by both data availability (the tropical parameter crisis) and by scale-specific variability.
U2 - 10.1007/978-94-017-3021-1_15
DO - 10.1007/978-94-017-3021-1_15
M3 - Article
SN - 1385-1314
VL - 80
SP - 151
EP - 158
JO - Nutrient Cycling in Agroecosystems
JF - Nutrient Cycling in Agroecosystems
ER -