The health of natural bodies of water and the entire planets ecosystem is threatened by excessive nutrients entering the oceans and other natural bodies of water. In this article, I discuss one of the sources of those nutrients, fertilizer runoff. In future posts, I will discuss other sources, human and animal wastes, and industrial sources.
Anyone who has lived in Washington has seen the changes to our beaches. Beaches had sand, upon which you could walk, sit, or play. You could wade into the water and see through it down to a depth of several feet. Now the beach is littered with seaweed and the waters are murky brown-green with algae.
An increase in available nutrients, primarily nitrogen and phosphorous has created the increase in algae and other plant materials in the Puget Sound and Pacific Ocean. The sources of these nutrients are fertilizer run-off, human and animal waste, and industrial pollutants.
We could ignore aesthetics, but algae blooms near the surface block light from getting down to any deeper waters, depriving the deeper waters of oxygen. Fish and other life die off leaving huge dead zones. Anaerobic bacteria that make their living by metabolizing sulfur compounds thrive in the absence of oxygen and create hydrogen sulfide as a waste product. Hydrogen sulfide is highly toxic and smells like a fart. Some former mass extinctions may have resulted from anaerobic bacteria creating so much hydrogen sulfide that it killed most land land species as well as ocean life.
You can see more is at stake than simple aesthetics, death by global fart if this isn’t addressed, a mass extinction including the human race. To prevent mass extinction by global fart we need to do two things, stop fertilizer runoff and improve sewage treatment sufficiently that substantial amounts of nitrogen, phosphorous, and other nutrients, are not discharged from treatment facilities.
Fertilizer runoff comes from residential and agricultural sources. Fertilizing your lawn then watering it excessively carries nutrients off into storm drains which drain untreated into lakes and streams. Is a green lawn is really worth mass global extinction by fart? Help your grass grow healthy using aeration, a mulching lawn mower and allowing your grass to grow slightly taller.
Only water enough to soak down several inches. Grass roots do not grow deeper than this so additional water only leaches nutrients from the soil, including any fertilizer you added, down the storm drains off to your local stream. If you use a mulching mower so all nutrients consumed by growing grass are returned to the soil, and water properly so that minerals aren’t leached from your soil, you should not need fertilizers.
The practices that allow a grass lawn to grow green without causing runoff also apply to food agriculture. Get onto Google Maps and view an agricultural region such as central Washington state, you will see these big circles, rows and rows of huge circles. These are agricultural fields in which a sprinkler system that consists of a central hub with a long pipe which has a series of wheels supporting it out from the central hub, and has sprinklers mounted on it. It irrigates the land by spraying water as the pipe makes a complete 360 degree turn through the field around the central hub.
This method of irrigation is simple, cheap, and extremely wasteful. Instead of going into the soil where needed, water is sprayed on top. Much is lost to evaporation as the spray travels through the air before it even gets to the crop. Usually, these are just run on timers and take no consideration of the amount of moisture already in the soil and how much the plants actually need.
Over watering causes the water to go past the roots, leaching minerals from the soil as it does, down past the top soil into the clay below and eventually into the ground water where it caries the minerals leached from the soil with it, or it runs off the top into nearby streams. Minerals leached from the soil require replacement by artificial fertilizers.
This type of watering should be replaced by controlled drip irrigation where water is placed directly into the soil and monitored at the depth of the roots so only enough water is provided as needed. This practice eliminates water waste and eliminates mineral leaching. The system is more expensive initially but saves the farmer the expense of unnecessary fertilizer and water. More importantly, it prevents nutrients from entering natural bodies of water.
We need to take these steps to preserve our biosphere which provides us with sustenance.