Continually logging and re-growing tropical forests to supply timber is reducing the levels of vital nutrients in the soil, which may limit future forest growth and recovery, a new study suggests.
Continually logging and re-growing tropical forests to supply timber is reducing the levels of vital nutrients in the soil, which may limit future forest growth and recovery, a new study suggests. This raises concerns about the long-term sustainability of logging in the tropics.
Trees of recovering tropical forests were found to have tougher leaves, with lower concentrations of the nutrients phosphorus and nitrogen – both essential for plant and tree growth - than trees of old-growth forests. This suggests that multiple cycles of logging and recovery irreversibly remove phosphorus from the forest system, and are pushing the nutrient content towards ecological limits.
“Old-growth tropical forests that have been the same for millions of years are now changing irreversibly due to repeated logging,” said Dr Tom Swinfield, a plant scientist in the University of Cambridge Conservation Research Institute, and first author of the paper published in the journal Global Change Biology.
Soil nutrients including phosphorus come from rocks, and are taken up by trees through their roots. Cutting down the trees causes these nutrients to be lost through soil erosion, gas emissions, and removal of nutrients in the extracted timber. The researchers estimate that as much as 30% of the available phosphorus in the soil is being removed from tropical forest systems by repeated logging.
Read more at University of Cambridge
Image by Evgeni Tcherkasski from Pixabay
