Why does your life depend on soil fertility?
Can lack of soil fertility wipe out civilization?
What did the Mayan and Indus Valley peoples, the Greeks and the Romans, the civilizations of Central America and Mexico have in common? According to scholars, they all eventually suffered oblivion due to the significant role of soil erosion and drought, and deforestation, making agriculture unproductive and impacting the survival of its people. In Dirt: Erosion of Civilizations, author Daniel R Montgomery takes us through a compelling, sweeping journey through steppes, hill slopes, plains, valleys, deserts, river deltas, plateaus, lowlands, highlands, and every other contour of geography, as he traces the fall of civilizations across the world.
“While environmental degradation alone did not trigger the outright collapse of these civilizations, the history of their dirt set the stage upon which economics, climate extremes, and war influenced their fate,” he writes. Rome, for instance, he says, “didn’t so much collapse as it crumbled, wearing away as erosion sapped the productivity of its homeland.”
Soil, not oil, says Montgomery, is our natural wealth because the simple truth is, soil nourishes us. In the absence of soil fertility nothing will grow in it. And if nothing grows, it is apparent that we eat nothing because we haven’t reached a point where lab-grown food can feed the entire humanity. Sure, efforts are on in hi-tech labs in many pockets of the world to grow meat-and-plant-type foods. Enthusiastic supporters of such trends, including the anti-animal farming lobby, green messengers, and earth lovers, see a cause to celebrate. The Massachusetts Institute of Technology (MIT) recently managed to grow plant tissues in its lab.
This innovation created a buzz about how the plant-in-a-petri-dish breakthrough may lead to furniture from lab-grown trees. Keeping this matter aside, can anybody guess how long it will take to feed the world’s nearly 8 billion mouths from lab to table or petri dish to dinner plate? Till such time, we need to continue to hope for good harvests and healthy soil to feed humanity and pay heed to the counsel of soil scientists. If we ignore their predictions, we will pay the price.
In a research paper titled, Soil and humanity: Culture, civilization, livelihood and health, Minami Katsuyuki, a soil scientist of the Kitasato University in Sagamihara, Japan, says, “Soil is the basis of life, civilization, culture, livelihood, and health. Therefore, if humanity cannot pass healthy soil to the next generation, human cultures cannot be passed on and will surely perish.” Therefore, the subject of soil fertility, or the lack of it, is a matter of life or death.
The many roles of soil
Soil is not just a one-note performer, however. Beyond growing food, it renders other essential services.
- The soil in its healthy, normal state is nature’s best filtration system: it decontaminates water to protect groundwater reserves.
- It holds on to the water for crops to grow.
- It tethers vegetation giving the earth its green cover, prevents floods and landslides.
- Apart from food, soil fertility helps grow raw material for a thousand necessities of our daily life, including medicines and fuel.
- Soil is a biodiversity hub that provides a perfect home to millions of micro-and macro-organisms to thrive, critical for the continuation of the species.
- Soil provides forage for animals. Think about this: if the cow does not eat grass, how will it give milk? And where does the grass grow? You get the point.
- Across cultures, in literature, poetry, drama, and folklore, the soil is intimately linked to human emotions and existence. People worship, revere, and love Mother Earth because she provides us with sustenance. The ground is her cloak in whose comforting folds societies have found refuge and nourishment since the dawn of civilization.
In short, healthy soil is our very life. And if we degrade it, abuse it, deplete it, it is at our peril.
What makes soil healthy?
Its ability to nourish plants, essentially.
Soil is a complex mix of organic matter, including millions of microorganisms and invertebrates, vegetation debris, minerals, water, and air. Soil fertility is about having all the essential micronutrients, which, along with oxygen, carbon, hydrogen from the air and nitrogen, potassium, phosphorus, etc., from the soil, support plant growth, and allow micro-and other organisms to thrive in it.
There must be the right combination of air and water in the soil for optimum plant growth. Excessive moisture leads to an imbalance of air availability for plants and vice versa. The soil must be loose enough to provide penetrative depth for roots to take hold and allow air and water to co-exist. Conversely, roots cannot penetrate soil that is dense and compacted, leaving the plant weakened.
Formed over millions of years through the disintegration of rock due to weather and chemical changes, each region in the world has specific characteristics of soil based on a combination of the above.
There is an organic cycle of nutrient exchange between soil and plants, with organisms and animals playing a role. A prolonged disruption in this organic cycle through human-made interventions can alter the efficacy of the biomass, making it difficult for soil to nourish plants effectively.
Are we damaging soil?
Yes, say soil scientists.
According to a United Nations report, 33 percent of global soil is in moderate to highly degraded condition. Erosion, nutrient depletion, acidification, salinization, compaction, and chemical pollution are the leading causes.
According to the FAO (Food and Agricultural Organization of the United Nations), by 2050, the world may see a 10 percent drop in crop yields due to soil erosion which amounts to a loss of millions of hectares of crop-growing land. So, when countries talk of food security, they must keep this reality in mind.
So, where are we going wrong with soil fertility?
The world’s population is exploding, and urban spaces are expanding.
Industrialization is uncontained (cultivable land is being encroached on). The pollution of land and water from toxic dumps and waste dispersal is rampant, and deforestation is unconscionable. Farmers are over-farming, industries are over-manufacturing, masses are overcrowding into spaces meant for growing crops.
The habitats of animals, insects, plants, and microorganisms are altering beyond sustainability. Throw into this mix the reality of climate change, and we have a perfect recipe for soil RIP. The most critical form of damage to soil is the erosion of topsoil.
Across the planet, in each region, the soil is mainly described as having two main layers – topsoil and subsoil. Topsoil is the cradle for the birth of most plants on the planet. According to the UN, soil hosts a quarter of the planet’s biodiversity and provides about 95 percent of our food. The formation of topsoil is a long natural process that takes thousands of years. But just over a few decades, we seem to have damaged soil fertility with the indiscriminate use of pesticides and fertilizers, over-tillage of land, and excessive crop rotations.
As a result, the organic wealth of the soil is slowly turning inorganic. Floods, excessive rainfall due to climate change, and other detrimental natural forces also play a role in soil erosion.
Soil fertility and productivity: Is there a difference?
Yes. Strange as it may sound, soil scientists will tell you that all fertile soils may not be productive, but all productive soils are fertile. Soil productivity, according to them, is a combination of soil fertility, management, and climate.
While the soil’s inherent properties are good, many other factors also need to come into play to make it effective. Location, climate, air quality (carbon dioxide and oxygen levels), climate, sunlight, pests, water table, all these can potentially affect fertile soil. A good analogy would be like sleeping in a beautiful bed, on expensive sheets, on the ergonomically designed mattress and pillows. Great stuff, really, but can they alone assure you of a good night’s sleep. What about other important factors? Like room temperature? Is the room too hot? Too cold? Too dry? Noise levels? Is there traffic noise outside? Light? Is there too much light from the streets? All these will affect your sleep quality too.
Soil fertility and soil productivity have a similar connection with the presence or absence of conducive factors.
Whatever is the most deficient will dictate growth
One of the big concepts applied to soil fertility is the Liebig law of the minimum, which according to many sources, was first developed by German botanist Carl Sprengel in 1840 and later popularized by German scientist Justus von Liebig.
The law states that the plant’s growth is not based on the total resources but dictated by the scarcest resource. So, if, let’s say, phosphorus is the element in the least supply, it will impact all areas in the plant’s growth it promotes. Just as in humans, all things being equal, an extreme deficiency in Vitamin D, for example, will lead to health problems that will be distinctive of its deficit.
Some researchers also call for agronomists to rename the law as the Sprengel-Liebig Law of the Minimum (On the Origin of the Theory of Mineral Nutrition of Plants and the Law of the Minimum, RR van der Ploeg, W. Bohm, M.B. Kirkham), given the inconsistency in attribution by many experts.
The way forward: What can governments, policymakers, and farmers do?
According to Jonathan Davies, Drylands Coordinator, Ecosystem Management Programme at the International Union for Conservation of Nature (IUCN), many countries, not surprisingly, are taking action to restore soil health.
The UN, according to Davies, has included soil health in its 2030 Sustainable Development Goals (SDGs. As of May 2018, 116 countries were setting up national targets for soil health to meet the SDGs, with support from IUCN, he writes in his report.
The United Nations Framework Convention on Climate Change report, 2019, highlighted the efforts of some countries in combating soil degradation. Among them are:
- California, the US state, sees the effects of climate change with severe wildfires every year. As a result, it pursues state-funded land restoration and management activities to increase soil carbon sequestration to reach its GHG (Greenhouse Gas) emission reduction goals and keep its soil healthy and productive. The state also uses soil samples for establishing baselines and requires annual soil samples from participating farmers.
- Ethiopia, says the report, is among the pioneering countries for soil health targets. Land degradation is estimated to cost the country as much as US$4.3 billion annually. So, Ethiopia has taken up cropland and grassland farming on nearly 30 percent of its total surface area to protect and restore its arable land. It is also resorting to agroforestry – planting trees alongside, says the report.
- Italy is working to protect 24,250km2 of forest, grassland, and cropland from degradation by promoting sustainable agriculture.
- Brazil uses a scientific approach to agriculture with soil conservation techniques, bio fixation of nitrogen, regular monitoring, field sampling, and remote sensing. It has helped catapult it from being a low agriculture country in 1970 to a significant exporter of agri-products today, says the report.
- ASEAN: This bloc of member states tackles soil fertility by attempting to reduce damaging practices such as deforestation, mining, destructive farming practices, urbanization, and coastal pollution, a reprehensive of ASEAN told the IUCN workshop.
- Workshops such as the IUCN and other convening bodies also stress the importance of regional and global cooperation in soil conservation methods. The exchange of scientific breakthroughs, sustainable practices to improve soil carbon reserves, boost organic concentration and disseminate evidence-based results to farmers through technology and diverse communication strategies at community, local, national levels are awareness and knowledge spreaders.
The UNFAO’s Global Soil Partnership, established in December 2012, with 192 FAO member nations, seeks to cohere the collaboration and efforts of governments, policymakers, and farmers to advance the efficiency in soil sustainability. The hope is, it will continue to be an increasingly purposeful mechanism in promoting this urgent goal.
If the soil breathes, so do we
According to the Status of the World’s Soils report by the FAO, what we can manage, we can measure. The report urges governments, policymakers, and farmers to adopt a collaborative approach to improve soil and land management practices. Some of the methods the report mentions are:
- Minimize soil disturbance by avoiding mechanical tillage to maintain soil organic matter, soil structure, and overall soil function.
- Maintain a protective organic cover on the soil surface, using cover crops and crop residues to protect soil surface, conserve water and nutrients and promote soil biological activity.
- Cultivate a wide range of plant species – both annuals and perennials – in associations, sequences, and rotations that include trees, shrubs, pastures, and crops, to enhance crop nutrition and improve system resilience.
- Enhance crop nutrition and soil function through crop rotations and judicious use of organic and inorganic fertilizer.
NGOs across the world doing their bit
The role of NGOs in educating and supporting farmers to practice sustainable, productive methods to boost soil fertility and halt soil degradation is worth overstating. In proximity to grass-root needs, NGOs play a seminal role in vitalizing farmers to empower themselves with information and the right outlook to upgrade their methods in better farming.
The steady growth in organizations and even individuals who pitch in for soil conservation efforts is a globally visible phenomenon. In 2016, Food Tank, a think tank for food, listed 22 organizations doing great work in helping farmers switch to sustainable practices at the root of healthy soil awareness.
The Rodale Institute, a non-profit dedicated to organic and progressive agricultural methods, issued a white paper recently titled, Regenerative Agriculture and the Soil Carbon Solution that stresses the global need to return to ‘regenerative agriculture. One of the key findings of the report is that shifting crop and pasture management to regenerative systems can “draw down more than 100% of annual CO2 emissions, pulling carbon from the atmosphere and storing it in the soil”.
Governments, soil scientists, agronomists, policymakers, and environmentalists are tackling the issues of soil degradation and soil fertility, enabling farmers to practice sustainable agriculture. So, there is hope yet of negating the dire outlook for a planet suffering from deep environmental stress.
The way forward is to restore the balance between nature and humans, to respect the needs of the earth as it serves the needs of humanity. In the words of soil scientist Katsuyuki, “If people do not have an ethic for the environment, including the soil, the water, and the air, as we have ethics for people and society, the world will surely start to retaliate against humanity. Global warming and soil erosion are good examples.”