GAFSA is an efficient
fertilizer providing significant amounts of phosphorus, calcium, and other vital nutrients
required by plants and animals. These nutrients, taken out from the soil by plants, mainly
in their ionic soluble compounds, are indispensable for their proper growth and
development. It has a high rate of
dissolution giving readily available phosphorus (P) for initial plant growth, combined
with the advantages of the long-term residual effect. It increases the availability of
other major nutrients such as N and K, and reduces micronutrient deficiency. It has a significant
liming effect for acid soils and may constitute an alternative to liming in areas where
minimal applications of lime are sufficient and lime is not available at an economic cost.
Unlike
low reactive rocks that can
present high CaO content but low available Ca, GAFSA
appears
to be an efficient source of Calcium with regard to plant nutrition and liming effect, not
only because of its high CaO (45-50%), but most important, due to its high
reactivity. Historically,
fine grinding (200-300 Mesh Tyler sieve) was usually recommended for natural phosphate
rocks in order to increase the surface area and hence the dissolution of the apatite.
However countless research findings have established that fine grinding is not necessary
for highly reactive PRs with particle size range of 50 to 60% passing a 100-mesh sieve.
GAFSA responds to those criteria.
GAFSA is a soft sedimentary
phosphate with high internal porosity and a total surface area (unground state) even
greater than that of other finely ground materials. For this reason, it is used in several
countries of the world including United Kingdom, France, India, Indonesia, New
Zealand,
Australia and Brazil in its "as-received" state. Most of our customers
acknowledge that grinding adds to the manufacturing cost of PR. When the rock is too fine,
substantial amount of dust is noticeable which is extremely undesirable for loading and
unloading operations. The product is also not suitable for mechanized application.
Since the beginning of
the 20th century, GAFSA has been the focus of considerable interest from scientists
throughout the world. Its agronomic advantages have been reported on a wide variety of
crops and environments.
In 1995 and 1999, GAFSA has
been awarded two statements from IFDC (Alabama, USA), an International Scientific
Institution. Those statements corroborate the data reported by eminent scientists
throughout the world on its high reactivity and its fertilizer quality in direct
application.
