Truong Thi Nha stands just four-and-a-half feet tall. Her three grown children tower over her, just as many young people in this village outside Hanoi dwarf their parents.
The biggest reason the children are so robust: fertilizer.
Nha, her face weathered beyond its 51 years, said her growth was stunted by a childhood of hunger and malnutrition. Just a few decades ago, crop yields here were far lower and diets much worse.
Then the widespread use of inexpensive chemical fertilizer, coupled with market reforms, helped power an agricultural explosion that had already occurred in other parts of the world. Yields of rice and corn rose, and diets grew richer. Now those gains are threatened in many countries by spot shortages and soaring prices for fertilizer, the most essential ingredient of modern agriculture.
Prices of some fertilizer have nearly tripled in the last year, keeping farmers from buying all they need. That is one of many factors which has contributed to the rise in food prices that, according to the UN World Food Programme, threatens to push tens of millions of poor into malnutrition.
Protests over high food prices have erupted across the developing world, and the stability of governments from Senegal to the Philippines is threatened.
In the US, farmers in Iowa, desperate to replenish nutrients in the soil, have increased the age-old practice of spreading tonnes of hog manure on their fields. In India, the cost of subsidizing fertilizer for farmers has soared, sparking calls for policy reform.
The squeeze on the supply of fertilizer has been building for roughly five years. Rising demand for food and biofuels prompted farmers everywhere to plant more crops. As demand grew, the fertilizer mines and factories proved unable to keep up.
“If you want 10,000 tonnes, they’ll sell you 5,000 today, maybe 3,000,” said W. Scott Tinsman Jr, a fertilizer manufacturer and dealer in Davenport, Iowa. “The rubber band is stretched really far.”
Fertilizer companies are confident the shortage will be solved eventually, noting that they plan to build scores of new factories in the next few years, many in West Asia where natural gas is abundant. But that will probably create fresh problems in the long run as the world grows more dependent on fossil fuels to produce chemical fertilizers. Intensified use of chemical fertilizers is certain to mean greater pollution of waterways, too.
Agriculture and development experts say the world has few alternatives to its growing dependence on fertilizer. Some experts calculate that synthetic fertilizers made with natural gas have led to greater crop yields. In sub-Saharan Africa, where hunger and starvation have long been a threat, a lack of fertilizer is a primary reason yields lag behind the rest of the world. Efforts to get fertilizer into the hands of African farmers have been complicated by the recent price increases.