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Is it really a good idea to make compostable waste go away and never come back? 

Each year, taxpayers collectively spend millions of dollars to burn or bury compostables.  Much like a tribe of ubiquitous Gollums, they just want garbage — the biodegradable and putrefying fraction of the municipal solid waste stream – to go away and never come back. 

The desire to make disagreeable discards disappear into fiery furnaces or burial mounds is understandable.  But is it wise?  Is it fiscally responsible?  Is it really a good idea to make organic waste go away and never come back? 

Nature recycles everything 

Rocks weather and erode, creating sediment. With heat, pressure, and time, that sediment becomes rock again.  Plants and animals feed and drink from the earth, die, and decompose to replenish the soil that will sustain future generations of flora and fauna.  Water drops from the sky as rain, filters down to aquifers, upwells and evaporates back to the clouds to fall once more. 

In a fantasy land, it may be possible to keep using resources without a thought to replenishment.  But in the real world, organic waste – the decaying residuals of once-living things – must be recycled back to the soil to maintain life-critical soil functions.   

Some seem to think the destruction of organics to make energy is more important than rebuilding soil.  But pushing an organic-waste-to-energy agenda by sacrificing the soil makes no sense. Humans managed to survive for millennia without electricity and centralized energy systems.  Without soil’s life-essential contribution to food and clean water, people face extinction in weeks.  

So, which is more important, energy or soil? 

Make energy and rebuild soil?   

Organic waste from developed societies includes all types of vegetation, food, manures … even compostable plastics.  When turned into a quality compost, these once-lost resources can be used by anyone anywhere to replenish depleted soil.   

Happily, making energy and building healthy soil does not have to be an either/or proposition.  It is possible to extract energy from organic waste without destroying the beneficial properties that make it valuable to soil.   The organic waste streams from these processes can then be used as feedstocks in the manufacture of compost products. 

Unhappily, energy production from biomass is one of the most expensive ways to make energy.  Even solar and wind power can be more cost-effective. 

Furthermore, bioenergy technologies based on anaerobic digestion of organics are still too pricey to be practical in many places.  Where they do exist, the waste stream (digestate) is not always put to highest and best use (i.e. composted).  Instead, residuals may be landfilled or relegated to low-dollar-value reuse. 

But one day, as more communities opt to restore natural soil replenishment cycles and energy generation technologies become more efficient, extracting energy from biomass, followed by composting and compost use, can become the system of choice for organic waste management. 

In the meantime … 

The importance of healthy soil 

Where humans live, topsoil has been scraped away or eroded.  Nutrients are used up.  Compaction has destroyed the pore spaces essential to the transport of air, water, and microbes.  Without a regular infusion of new organic matter to correct these deficiencies, soil dies.   

There are lots of processes for generating energy, but there’s only one way to replenish disturbed soils in developed areas – feed them a good, wholesome diet derived from organic waste converted into compost.   

From farms to lawns to sports fields, soils require periodic applications of compost.  There’s no other way to easily and economically provide soil with everything it requires to retain water, nurture vegetation, and create the type of environment soil microbes need to support nutrient uptake, contribute to disease resistance, and degrade pollutants. 

The best news? In many metropolitan areas, efficient, high-rate composting – the type needed to successfully manage big, urban waste streams – costs no more than landfilling or incineration.  Often, recycling at a modern, industrial composting operation can be more affordable than traditional disposal.   

Composting makes organic wastes go away, but they come back as enriching soil amendments.  Biodegradables need to keep recycling, just like they have since the beginning of time. 

Breaking the natural soil cycle by incinerating or burying compostable waste is a bad idea that should go away and never come back.

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Compost is soil’s superhero

Sure, compost adds nutrients. But that might be this soil amendment’s least important function. 

Quite often, articles will mention compost as a replacement for some or all of the nutrients that might be provided to plants through applications of synthetic (man-made) fertilizers.   

That’s certainly true.  Compost delivers the macronutrients nitrogen, phosphorus, and potassium (NPK), plus a slew of plant-essential micronutrients that are missing from most synthesized fertilizer products.  Compost provides plants with a wholesome, well-rounded meal, not the nutritional equivalent of junk food. 

But what these fertilizer-focused articles rarely mention is the fact that the real value in compost use is not related to feeding plants, but to feeding soil … and soil does require a wholesome diet to function as a true soil and not a dead substrate. 

Compost feeds soil

Providing plant nutrients is just one of many soil functions.  Worms and other creatures that live in healthy soils help to physically break down food sources, then microbes take over to convert that food into plant-available form. 

Both physical and microbial conversion depend on a soil environment that can support those lifeforms.  If the soil is chronically too wet, too dry, too compacted  yada, yada  then it can’t support a healthy soil ecosystem.  That plot of ground may not be soil at all, but lifeless dirt. 

To countermand the impacts of human activity, disturbed soils require regular program of replenishment that includes organic matter and microbes.  Compost provides both.  Compost feeds soil.

Then, when it rains, soil retains that water, reducing runoff.  When runoff is reduced, so is erosion, sedimentation, and water pollution.  Because soil microbial activity also degrades pollutants, any stormwater that does run off is cleaner.  

That same microbial activity can help neutralize some soil-borne diseases, too. 

Improving plant nutrition, aiding in disease control, reducing water pollution, and retaining water are all important soil functions. 

But wait, there’s more. 

Compost as a carbon sink 

The build-up of greenhouse gases in the earth’s atmosphere is cause for concern.  As more greenhouse gases flood the atmosphere, temperatures increase. 

This rise in global temperatures influences many things, erratic and extreme weather being one of the most visible.  Subsequent climate shifts can impact people, crops, and livestock for hundreds of years. 

When used to amend soils, compost sequesters carbon.  This means the soil will act as a carbon “sink,” capturing and holding carbon in stasis – but only as long as the soil remains undisturbed.  When the soil is tilled, that carbon is released. 

Extensive use of compost for perennial crops and other long-term application(grasslands, tree farms, utility easements, etc.) can positively impact atmospheric conditions by reducing greenhouse gases.   

At the same time, the addition of compost rebuilds a topsoil layer that has been eroded or scraped away by farming, development, and other human activity.  Since topsoil loss has been identified as a significant threat to planetary health, second only to population growthits restoration is a global priority.   

At a time when nearly a third of the world’s arable land has become unproductive in just a few decades, compost really can be that superhero swooping in to save topsoil, save water, save the atmosphere, and save the planet.