The Fertilizer Dilemma — Promise and Peril
Nitrogen is essential for human survival, yet most of it in the atmosphere cannot be directly used by plants or humans. Over millennia, farmers relied on organic recycling—crop residues, manure, and fallow systems—to return nitrogen to soils. As populations grew, these methods proved insufficient. The nineteenth century saw a scramble for natural nitrogen sources, most notably guano and saltpeter deposits in South America, competition for which even sparked war.
The breakthrough came with the Haber–Bosch process, which converts atmospheric nitrogen into ammonia (NH₃). This technological leap enabled unprecedented crop yields, supporting global population growth from 1.6 billion in 1900 to over eight billion today. Approximately half the protein humans consume now originates from industrially fixed nitrogen, and synthetic fertilizer became the backbone of the Green Revolution.
However, as Vaclav Smil emphasizes in “Fertilizer Dilemma: Promise and Peril,” BBC Future, this success comes with profound environmental and efficiency costs:
- Only ~17% of applied nitrogen is absorbed by crops; the rest is lost to soils, waterways, and the atmosphere.
- Excess nitrogen fuels algal blooms, “dead zones,” and greenhouse gas emissions, including potent nitrous oxide (N₂O).
- For every unit of nitrogen consumed by humans, roughly ten units are applied to fields.
- Organic farming alone cannot realistically meet global food demand, especially in regions with degraded soils, limited water, or constrained access to inputs.
In sub-Saharan Africa, low fertilizer use and degraded soils severely limit crop productivity. Malawi’s experience in the mid-2000s showed that reintroducing fertilizer subsidies more than doubled maize production within a single year, highlighting the critical role of access and efficient use.
Fertilizer by the Numbers
ENERGY TODAY highlights the scale and inefficiency of global fertilizer use:
“Fertilizer, by the numbers” reports:
• 2.5 million metric tons of fertilizer are used by Americans for their lawns.
• 60% of the world’s fertilizer comes from China, Russia, the U.S., India, and Canada; China contributes about 25% alone.
• 42% of the potash used in the U.S. is imported, signaling import dependence for potassium fertilizer.
• 78% of all nitrogen fertilizer and more than half of phosphate and potash used in the U.S. goes to growing corn.
• 3.5 to 4 billion people are alive today because agriculture relies on synthetic nitrogen fertilizer from the Haber–Bosch process.
• 51% of applied nitrogen fertilizer worldwide is lost from farm fields rather than taken up by crops, with the U.S. responsible for 11% of total excess nitrogen.
• 1 ton of nitrogen fertilizer requires the energy equivalent of 2 tons of gasoline to produce.
• 40% of the energy used in the industrial food system is dedicated to producing fertilizers and pesticides.
• Making ammonia— a key step in fertilizer production—produces more O₂, N₂O, and NH₃ than any other industrial activity.
(Source)
These numbers underscore the inefficiency, energy intensity, and environmental impact of modern fertilizer systems.
Attapulgite Clay: Chemical Stabilization
Attapulgite clay, naturally found in Australia, is a fibrous, porous magnesium–aluminum silicate that can adsorb ammonia and ammonium, slowing nitrogen loss after fertilizer application.
Key benefits include:
- Reduced ammonia volatilization – nitrogen remains in the root zone longer.
- Improved nitrogen-use efficiency (NUE) – more fertilizer reaches crops, less escapes to the environment.
- Compatibility with current fertilizer systems – can be blended with synthetic fertilizers, compost, or manure.
By targeting chemical nitrogen inefficiency, attapulgite clay directly addresses some of the largest fertilizer losses identified by ENERGY TODAY.
Freshwater Diatomaceous Earth: Soil Enhancement
Freshwater diatomaceous earth (DE), particularly Badgingarra DE from Western Australia, complements attapulgite clay by enhancing soil function, water retention, and biological activity:
- Water retention – stabilizes moisture in the root zone, supporting nitrogen uptake.
- Soil structure improvement – reduces compaction in heavy soils and improves aggregation in sandy soils.
- Biological support – porous silica provides microhabitats for microbes that convert nitrogen into plant-available forms.
While DE does not directly adsorb ammonia, it ensures applied nitrogen can be effectively captured by crops, reducing losses through runoff, leaching, or volatilization.
Combined Impact: Attapulgite Clay + Diatomaceous Earth
| Challenge | Attapulgite Clay | Freshwater Diatomaceous Earth |
|---|---|---|
| Nitrogen loss / low NUE | Adsorbs NH₃/NH₄⁺, slows release | Enhances root access, microbial conversion |
| Energy-intensive fertilizer | Less fertilizer needed per yield | Better uptake reduces repeat applications |
| Soil and crop constraints | Efficient for high-demand crops like corn | Supports soil resilience in degraded or dry areas |
| Environmental emissions | Reduces NH₃ volatilization | Reduces nitrogen lost to leaching & N₂O |
Together, attapulgite clay and freshwater diatomaceous earth help farmers wield fertilizer more wisely—improving efficiency, protecting ecosystems, and maintaining yields sustainably.
Research, Development, and Trial Opportunities
AusDE promotes research and application of attapulgite clay and freshwater diatomaceous earth for agriculture.
Farmers, agronomists, and researchers are invited to trial these natural materials to evaluate:
- Nitrogen retention and reduced ammonia loss
- Soil structure, water-use efficiency, and microbial support
- Crop uptake and yield improvements
For more information or to request samples for trials, contact:
[email protected]
Conclusion
Modern fertilizer systems are energy-intensive, inefficient, and environmentally impactful, but attapulgite clay and freshwater diatomaceous earth provide natural solutions. Attapulgite stabilizes nitrogen chemically, while diatomaceous earth improves soil-mediated uptake. Together, they enhance fertilizer efficiency, reduce environmental harm, and support sustainable agricultural productivity.
References:
- Vaclav Smil, Fertilizer Dilemma: Promise and Peril
- ENERGY TODAY, Fertilizer by the Numbers