10+ fascinating things you may not know about soil
Soil is the silent engine that keeps the planet alive, and most people in the world don’t give it a moment’s thought. Now the world’s soil scientists have created a beautiful atlas that is written so the public can understand why we all need to take care
These are just crumbs of what you can learn from the first-ever Global Soil Biodiversity Atlas which maps the soil biodiversity of the entire planet.
This book pays tribute to soil. It has been written for the layperson, bringing together a huge number of the world’s experts on soil biodiversity to create a unique publication.
• Ninety-eight percent of all global daily calories derive from actions from the soil biodiversity. • Soils may contain more than 10,000 species per square metre. • A single gram of soil may contain millions of individual cells and thousands of species of bacteria. • That bacterial biomass can amount to 1-2 tonnes (the weight of a car) per hectare (2.5 acres) in a temperature grassland like those found in NZ. • Soil organisms play a huge part in maintaining critical processes such as carbon storage, nutrient cycling, plant species diversity, and a key role in maintaining soil fertility. • Earthworms and other soil organisms enhance soil productivity by mixing the upper soil layers, redistributing nutrients, aerating the soil and increasing surface water infiltration. • Earthworms increase crop yields by 25%, on average. • A typical mineral soil sample is 45 percent minerals, 25 percent water, 25 percent air and 5 percent organic matter. • Soil has varying amounts of organic matter (living and dead organisms). It is estimated that 5-10 tonnes of animal life can be found in 1ha (2.5 acres) of temperate grassland soil. • 10 tonnes of topsoil spread over 1ha is only a few millimetres thick. • Studies have shown that the rate of soil formation varies from around 100 years for 2-5cm of volcanic ash in warm humid climates to 1cm in 5000 years on hard rocks in cool temperate climates. • Soils are generally around 1-2m deep. However, the Phillipi Peatland in Greece is reputed to be 190m deep. • The 3000-million-year-old Nsuze Paleosol in South Africa is the world’s oldest soil deposit.