MSI09P4496 | |
Mardamootoo, T Ng Kee Kwong, K F Du Preez, C C | |
History of phosphorus fertilizer usage and its impact on the agronomic phosphorus status of sugarcane soils in Mauritius | |
periodical article | |
2010 | |
Sug. Tech | |
12(2) : 91-97 | |
En | |
En | |
The intensive use of phosphorus (P) fertilizers during more than 100 years of sugarcane production in Mauritius is believed to have built up the P status of the soils to excessive levels. Hence there may be a scope for reducing P fertilizer usage in order to lessen production costs in sugarcane cultivation and alleviate its hazard to surface water quality. A review of P fertilizer usage in sugarcane showed that the amount of P fertilizer used by the sugarcane industry rose from 790 tons P2O5 (mainly as rock/guano phosphates) in the early 20th century to a peak of 5 675 tons P2O5 in the 1970s before declining thereafter to 3 350 tons P2O5 in 2008, mainly in the form of ammonium phosphates. The currently adopted 0.1M H2SO4 extraction method was used to assess soil P available in the sugarcane soils. Soil test P data showed that in 2005/2006, 36per cent of the land still required P fertilization (P < 80 mg kg-1) while approximately 52 per cent had an excess of P (P ? 100 mg kg-1). Fields with excessive P belong to all soil groups and can be encountered throughout the island. Less than 15 per cent of the soils had an optimum soil P (80 ? P < 100 mg kg-1). With only 31 per cent of the soils having a highly excessive P status (P ? 150 mg kg-1), this study indicates the belief that past P fertilization had invariably led to an excessive soil P status in Mauritius is unfounded. Also variation in soil P status as a result of differences in management between small and large planters could also not be discerned. | |
sugarcane phosphorus soils Soil P inorganic phosphorus organic phophorus phosphorus management soil P test fertilization plant nutrition pollution environment water pollution soil testing P saturation soil characteristics Phosphorus usage | |
Mauritius | |
Sugarcane: Soils and plant nutrition | |
Fertilization: Phosphorus | |
2010-12-09 | |
En | |
LIB | |
CAT | |
1 | |
CHEM |