130 131 That spoon that ensures life (and heals the soil) Emanuele Isonio @ Re Soil Foundation Thousands. Or rather millions, billions. These are the living beings in our soils. And not in an area the size of a football pitch, or in a cubic metre, or inside a child’s bucket. It only takes a simple tablespoon: fill it with soil and you will have, in there, more living organisms than all the human beings currently on the planet. The image that agronomists and soil scientists use to impress school students and non-insiders is also a perfect example of how much life can exist beneath our feet. Often unknown. Certainly underestimated. But fundamental to our lives, our future, our health. Indeed, the healthiness of the soil depends on these micro-organisms and, with it, its ability to provide ecosystem services: that is, to meet the needs of food production, carbon storage and hence the reduction of CO2 in the atmosphere, ensuring agricultural yields and nutritious, healthy fruit. The same spoon can also be useful to visually understand the difference between a healthy and a degraded soil. Just fill one with highly fertile soil and another with a soil depleted by years of aggressive and incorrect agronomic treatments. One glance at both, and you can easily see that the pale, sickly colour of the unhealthy soil is a silent cry for help. It’s up to us humans to hear it. On the other hand, soil scientists agree that in the last seventy years – in which agriculture has given way to agro-industry, the world population has grown, and fertile soils have too often been sealed off by infrastructure and cement – we have forgotten management techniques that we thought were outdated and instead, for centuries, they have preserved the very health of soils, whose life (or death) of entire populations depended on. There are countless publications highlighting how synthetic chemical compounds – starting from pesticides and phytosanitary products – that have been used for decades are becoming increasingly impactful. The Pesticide Action Network (www.pan-europe.info), which brings together NGOs from over sixty different countries, has underlined that the contamination of fruit and vegetables in Europe has increased by 53% in the last decade. The EU Regulation3, which aims to reduce the risks associated with phytosanitary products by 50% by 2030, emphasises that at least 54 hazardous substances must be candidates for substitution due to their impact on health, soil and ecosystems. Luckily for us, like a loving mother who forgives the mistakes of her children, nature is often benevolent and, despite the snubs it has received, it contains within itself the tools to allow us to fix the damage done so far. Once again, these allies of ours are tiny and live inside the soil. As long as we will listen to them. If we want to enshrine them in a single word that everyone can understand, we should speak of microbes. Even if that noun sounds with an often negative connotation to our ears, it literally encompasses a world within itself. In fact, there is a close connection between soil fertility and the biodiversity of the micro-organisms that populate it: they act as a veritable bank of resources which the plant can selectively draw from, according to its needs, contributing to the decomposition of organic substances and the release of essential mineral nutrients. Components of a virtuous circle that allows plant and grasses to grow better and thus, in turn, to fulfil their functions, among which stands that of giving new life once dead, favouring the spread of micro-organisms that populate the subsoil, while avoiding many of the phenomena leading to soil degradation. Secrets best known to farmers, true custodians both of soil and its future for hundreds of years. Today, all this has become a thriving field of study for researchers on every continent, committed to systematising the use of micro-organisms to heal soils, preserve their fertility and ensure adequate agricultural yields. Agronomists from the US Department of Agriculture and the Agriculture and AgriFood Canada agency are, for example, engaged in analysing the present microbial communities in order to assess soil health through them. The goal: to offer practical solutions as an alternative to the use of chemical inputs. Their research, which has been going on for about twenty years, has shown that some plants are more helpful than others in maintaining soil balance. For example, fields cultivated with monocultures such as soya have the worst health status. The corn ones are in the middle. On the other hand, those permanently covered with grass and rich in gorse, a plant widespread in North America, boast the greatest biodiversity of micro-organisms and a greater presence of fungi. 3 see Regulation (EC) No 1107/2009 of the European Parliament and of the Council of 21 October 2009 concerning the placing of plant protection products on the market and repealing Council Directives 79/117/EEC and 91/414/EEC – online @ eur-lex. europa.eu/eli/reg/2009/1107
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