"After three cultivation-fallow cycles, available soil P declines by 44%, and one-time P inputs from biomass burning decline by 76% from mature forest levels," they wrote.
The team added that the lack of a forest's canopy also resulted in hampering an area's ability to replenish phosphorus levels.
"The decline in new P from atmospheric deposition creates a long-term negative ecosystem balance."
The ongoing decline of the nutrient, which is a key component in the growth of organisms, triggered a "feedback" effect, they explained.
It could affect the growth of plants in the study area, and "may induce a shift to sparser vegetation", they warned.
As well as the area's ecosystem, the researchers added that local farmers were likely to be affected.
"Without financial support to encourage the use of fertilisers, farmers could increase the fallow period, clear new land, or abandon agriculture for off-farm employment," they wrote.
"[The farmers'] response will determine the regional balance between forest loss and forest regrowth."
