Agriculture is the biggest way that humans impact our landscape. Over 35% of the world’s ice-free land is dominated by agriculture. In Australia, that number reaches over 50%, helping to nourish our booming population. From crops to stock, the land provides us with so much. To honour agriculture, ‘Kiss the Ground’ tells a story about the most important, and often overlooked, element in the sector: soil. The 2020 environment documentary largely focuses on the United States, and here we both review the film as well as explore what it means for our Australian soil.

Our definition of soil

Soil is more than just dirt. It’s a complex and dynamic structure made up of water, air, and organic microbes to help grow our nutritious foods. Soil is a valuable carbon-sequestering resource that we need to preserve, as it can easily be damaged by water, wind, or agricultural practices. Techniques of deep tillage, heavy pesticide use, and cleared fields promote soil loss or degradation. On the other hand, there are a number of factors that help to build topsoil. In particular, decaying organic matter, nutrient-rich animal droppings, and cover crops whose roots help to give the soil structure and protect it from being carried away.

Here’s a trailer of the movie:

Documentary review

The Kiss the Ground documentary begins with a powerful introduction showing the current and future impacts of climate change. After rather intense scenes, it quickly moves into a lighter atmosphere: one of hope. With a mix of A-list celebrities and soil science experts to act as narrators, the documentary presents an engaging history of agriculture and the impacts of humans on soil health. By describing the emergence of tillage, pesticides and other agricultural discoveries, the film exposes just how fragile the world’s soils are. Since the Green Revolution began in the 1950s, we have lost ⅓ of the world’s top soil. Even more frightening, experts suggest the remaining topsoil will be gone within 60 years. Gabe Brown, a spokesperson and regenerative ranger in the United States, reframes this as “60 harvests to solve the problem” to bring hope back into the narrative.

The film takes a solutions-orientated perspective to educate the audience on more environmentally-friendly agricultural processes that help maintain soil. These include increasing biodiversity by avoiding monoculture cropping, no-till seeding techniques, responsible animal-integration, large-scale composting and continuous cover cropping. These techniques all aid in improving soil structure, helping the land to retain more water after rainfall events and avoid nutrient-leaching. As a number of experts in the film remind us, “if we look after our soils, our soils will look after us”.

What does this mean for Australian soils?

Kiss the Ground, although an excellent documentary which details the function and importance of soil in agriculture, takes a US-centric approach. Australian soils are different in structure, microbes, and agricultural use as a result of different weathering processes and age. You will likely have noticed the bright red hue of Australian soils if you’ve ever driven across the Simpson Desert or strayed far from a major city. The unique colour is a result of oxidation, or rusting, of iron in the soil over long geological time periods. Our soils have remained untouched by glaciers or soil-making events for millions of years, leaving them to weather and erode slowly. This has left the continent with largely nutrient-poor soils, often covered with scrub and used for cattle or sheep grazing. But this doesn’t mean our soils aren’t important, it means we must care for them even more.