According to the fertiliser association, consumption was up by 16% in 2011 against 2010, driven by imports. Such increase does not correlate with the land expansion observed over the same period, which suggests more usage per ha of arable land. Too much fertiliser leads to soil fatigue and is not a sustainable direction for agriculture.
The FAO - in a 2004 report about fertiliser use in Brazil - stated "There is a close relationship between the consumption of fertilizers and crop production in Brazil. Between 1970 and 2001 agricultural production in Brazil, represented by the sixteen most important crops, increased by 3.4 times and the consumption of fertilizers increased by 4.4 times. During this period the cropped area increased only 1.5 times, rising from 36.4 million ha to 56.2 million ha". This is still true today, judging from official data.
Here is what the FAO says about soils: "In general, the fertilizer nutrient balance in the Brazilian agriculture is unsatisfactory. The quantities of nutrients removed are higher than the quantities supplied. Thus soils are being progressively depleted of nutrients. This represents a threat to long-term agricultural sustainability.
As regards the ratio between the nutrients, by international standards the use of nitrogen is low in relation to phosphate and potash. Concerning the types of fertilizers, Brazil has an unusually high proportion of nutrients, over 80 percent, applied in the form of compound fertilizers. It is also one of the few countries where the use of single superphosphate has increased in recent years, partly due to the demand for this fertilizer for use on soybeans, owing to its sulphur content". Hence the strong expansion of soy would be expected to boost use of sulfur-containing fertilisers over large areas.
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