Spreading manure on crops recycles the nutrients, but as it decomposes it releases methane. And lots of it. Agriculture is the largest source of methane emissions globally. Each year, methane from livestock manure has the warming equivalent of 240 million tons of carbon dioxide, or the same as the annual emissions from 52 million cars.

I saw plastic greenhouses as far as the eye can see from the train as I traveled across Shandong Province to visit the Shandong Academy of Agricultural Sciences. Ninety percent of the world’s plastic greenhouses are in China, covering 3.3 million hectares, about the area of Maryland, with the majority in Shandong.

On a rainy July afternoon in 2017, I was in Jinhua, China, a city just south of Shanghai, to visit a pig farm. This was not just any pig farm—the Mebolo farm grows pigs that become the prized Jinhua Hams, a Chinese delicacy for nearly 1500 years. Long before Italians produced prosciutto and the Spanish their Jamón serrano ham, Marco Polo discovered Jinhua ham in the 13^th century and brought ham-making techniques back to Europe.

One year after the Sichuan earthquake, while visiting villages near Wenchuan, I asked local officials planning reconstruction about their plans for wastewater treatment. As an agricultural engineering professor, I was not surprised to learn that they had no plans. It was not that a wastewater treatment system was too expensive, they worried that it would be too big.

China’s food security is rooted in its soil.  Sadly, more than 40 percent of China’s soil is degraded from overuse, erosion, and pollution. The government’s 2014 soil survey revealed that 19 percent of China’s farmland was contaminated by metals such as lead, cadmium, and arsenic as well as organic and inorganic chemical pollutants. As part of its growing war on pollution, China’s central government enacted a new soil pollution law on January 1, 2019, to clean up contaminated sites. However, this new law targets just one of the many critical soil quality issues that reduce agricultural yield but does not address the problem of compacted soil.

As an agricultural engineering professor, I was excited to visit and tour the farm village Houbali, in southwestern Shandong Province. I found myself standing among newly constructed high-rise buildings, a vastly different community than I had expected to encounter. A bicycle repair shop was setting up alongside other bustling businesses in the first-floor storefronts. Farm families occupied apartments in the upper floors and a beautifully landscaped park and playground were a short walk away. This neighborhood looked like a transplant from Beijing, but these modern buildings were a newly developed farm village surrounded by agricultural fields. The new buildings brought together the residents of four old, nearly empty or “hollow” villages.