By mimicking the structure of the biological communities that created good soils in the first place, farmers can rebuild soils. This process entails growing perennial plants over several years, such as a pasture, which limits tillage to the establishment, keeps a living cover year-round, and produces more biomass each year than is decomposed. Clearly, when compared to today’s “every year” industrialized agriculture, this represents a trade -off between immediate harvests and sustainable harvests. Soil is also a major pool of carbon in the world and can act as either a “carbon sink” to pull CO 2 out of the air or a “carbon source” to release CO 2 and methane, depending on whether it is in a condition to support profuse plant growth or not. Rising heat and drought tend to drive soil towards being a carbon source, which would make it a “positive feedback” for amplification of global heating. TaaL: Viewed from space, the soil on top of E arth’s crust is far thinner than human skin – and it is from this infinitesimally small layer from which all complex terrestrial life springs. Mass- production farming, as it’s done in your so - called “first world,” is increasingly a matter of pouring fertilizer, herbicides and pesticides on what is largely inert and depleted soil without much micro-life: its function is just to hold the plants upright. This works, but in addition to causing problems like oceanic dead zones and toxic side-effects from runof f, it’s very fossil - energy intensive and is thus a temporary expedient. That being the case, it might be good to consider you will someday need to live as earlier generations did. Yet earlier generations had a soil resource which had been developed for tens of thousands of years. At current trends of hemorrhaging into your waterways, your topsoil will be gone before 2075. When was the last time you thought about topsoil? Humans in advanced economies don’t think about it much because right now you don’t ha ve to. But in the long run topsoil spells survival.
The Bottom Line: Soil is the irreplaceable substrate for sustainable life on Earth. Recent human activities have greatly degraded it.
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