In particular, 33 per cent of land was moderately to highly degraded due to erosion, salinisation, compaction, acidification, and chemical pollution of soils.
It said erosion carried away 25 to 40 billion tonnes of topsoil every year, significantly reducing crop yields and the soil's ability to store and cycle carbon, nutrients, and water. If action was not taken to reduce erosion, by 2050 the global loss to that date would equate to roughly all the arable land in India.
All around the world, everyone wants to be fed, but can this be achieved without damaging our global farmlands?
That was the question posed for the 2018 Hot Topic, co-ordinated by Lincoln Envirotown and hosted by radio personality and skilled moderator Kim Hill, held at Lincoln University.
The expert panellists debated the issue from all sides: Are we degrading our soil cover? Is this most precious of resources in any danger? Do we take our soil cover for granted? How important is the ecosystem of the soil, the production of safe, healthy food and preventing pollution and erosion?
Trish Fraser, a soil scientist at Lincoln Plant and Food Research, Ants Roberts, chief scientific officer at Ravensdown, Prof Mike Hedley from Massey University and Andy MacFarlane, a prominent farmer and company director, brought their expertise, and opinions.
Soils are central to agricultural business, Ants Roberts argued. They function as complex ecosystems and are hugely interdependent mixtures of chemical, biological and physical processes, which farmers and growers need to work with, he said.
"Soil is the approximate 10 to 100cm layer of land surface that farmers and growers rely on for food production. Assuming that people want to eat, then up until very recent times much of their nutrition has been from products grown in, or on, soil."
He pointed out that in First World countries about 1per cent of the population provided all the nutrition to the other 99 per cent, thereby freeing the masses of the necessity to forage for food, enabling them to pursue whatever activities they wished, including criticising those who feed them.
Soil takes thousands of years to form and, once built on or sealed over, it is not a reversible process. We can't afford to be short-sighted, allowing the destruction of our precious resource.
For Trish Fraser, who grew up on a mixed-cropping farm in the north of Scotland, too few people beyond those in the agricultural industry or with interests in gardening seemed to be aware of this connection and the important role soil played in their everyday lives.
Soil was no longer high on, or even on, the agenda, for the majority of the population, she lamented, yet it was fundamental to the nation's economy and the wellbeing of Kiwis.
Following years of research, understanding of how we should best look after our soils had improved vastly and some management practice recommendations had changed and would continue to change and evolve as understanding grows.
"Let's all help to bring the importance of looking after our precious soil resource into the conversation too."
She pointed out that pressures from population growth, urban expansion and road sealing were irreversibly locking up some of our best soils each year. She said land developers have their eyes on the land for housing, bearing little regard to whether the soils have special productive capacity.
"Soil takes thousands of years to form and, once built on or sealed over, it is not a reversible process. We can't afford to be short-sighted, allowing the destruction of our precious resource."
Andy MacFarlane said farmers were willing to learn and adapt and were showing global leadership in some aspects of how to grow soil, and the ecosystems it supports.
"Our young country, and young soils, are more fragile than many around the world. As a result, our forebears have made mistakes, some of which are irreversible, and we are still learning lessons, every year, ourselves."
He said he has seen great examples, in town and country, of how to improve the life-supporting capacity of soils through great science, great innovation, and great human interaction to create ideas that integrate that knowledge into production and conservation systems.
His family works irrigated land in Mid Canterbury, focused mainly on dairy farming, with some deer and beef production, and it has won several prestigious environmental awards.
People needed to understand that there was more than one right way to do things, he said, and that in order to learn minds must be open to change, and be willing to share.
Prof Hedley argued the productive capacity our soil was under threat and people had to realise that it would not last forever. "Soil — are we treating it like dirt," he asked. "What people understand as important soil and soil properties won't last forever naturally."
Efforts were being made to "freeze in time" important functions and properties of food and fibre producing soils through conservation practices and management inputs. He said urban populations had evolved to undervalue food and fibre, unaware of whether the supply chain was sustainable or of its impact on the environment.
"The main reason we have treated soils like dirt is because of the financial opportunity to produce food and fibre for large urban populations."
He said Kiwi farmers and growers had received conflicting messages about needing to produce a low-environmental-impact product in a fluctuating market. Specific resources were needed to ensure soil function for food and fibre production.
