Sustainability of our food production – part 1
The amount of food and water we consume will not be sustainable for future generations due to the depletion of our natural resources. In the last 40 years, 30% of arable land has become unproductive, and 25% of the planet’s soil is severely damaged. What many people might not realize is that our fondness for beef and dairy products has contributed to these environmental problems.
Almost a third of the United States, about 0.7 billion acres, is pastureland. It provides just one-third of what cattle need to grow. Trees in many forests have been removed to grow crops or let cattle graze, upsetting stability of climate and water resources. Overgrazing of pastures has caused the loss of half of all topsoil in recent decades. The other two-thirds of cattle fodder is provided by grain and corn harvested from 78 million acres of high-quality cropland. While soil fertility is naturally maintained by growing diverse plants, growing mono crop depletes the soil, so artificial fertilizers must be added.
The fertilizer run-offs from corn and grain fields and leaching from manure ponds are estimated to make over half of all U.S. streams unsuitable for aquatic life. When these contaminated streams empty into coastal environments, the nutrients stimulate excess growth of algae that subsequently die and sink to become available for bacteria to decompose in bottoms waters. As bacteria decompose the dead algae, they also consume oxygen until most or even all of the oxygen is removed from the water so that life (e.g., fish, shrimp) can’t be supported. The size of such dead zones has continued to grow.
Cattle are producers of methane, a greenhouse gas 23 times more potent than CO2 gas in global warming, made by bacteria in their ruminant digestive systems which help them to convert feed to nutrients. A cow releases between 70 and 120 kg of methane per year, which is equivalent to the CO2 produced annually by the average gasoline burning car. Finally, each cow requires about one gallon of water per day for each 100 pounds of cattle weight. With a world cattle population of around 1.5 billion, the impact of their methane release and need for fresh water is significant. Thus, our current maintenance of cattle to provide man with protein and milk has upset the equilibrium of our natural environment.
The great impact on our environment by man’s beef consumption is obviously unsustainable as our global population continues to grow, and climate change is predicted to decrease crop yields. Fortunately, we can move towards a diet which replaces red meat with other meats (e.g., chicken and fish) or plant-based proteins to lower our impact on the natural environment, not to mention reducing our risk for diabetes, heart disease and certain cancer. In the next installment, a more sustainable and healthy diet will be discussed.