Waikato Regional Council senior technical advisor Bala Tikkisetty says soil is the most important resource to any nation, more importantly for farmers.
But he points out that in NZ we lose it to the ocean about 10 times faster than the rest of the world, with about 192 million tonnes sliding into the sea every year.
That equates to an astonishing 1.1 to 1.7% of total global soil loss to oceans, despite us having only 0.1% of total land area.
Tikkisetty says these statistics are a reflection of the erosion that results from our mountainous and hilly landscape, heavy rainfall events and some of our land use practices.
This will further intensify with impacts of climate change.
“Many New Zealand soils are inherently susceptible to erosion because of high rainfall, soft lithology, and steep topography.
“However, agriculture is not solely responsible for high levels of sediment input to fresh water across New Zealand. Urban development, mineral extraction, and earthworks also contribute to the problem.
“And, as we all know, the resulting sedimentation of our waterways contributes to poor water quality and interferes with aquatic biodiversity, as well as affecting the backbone of our country’s economy – farming.”