The Role of Composting in Advancing Sustainable Development Goals

Mitigating Climate Change and Promoting Sustainable Cities (SDG 11 & SDG 13)

A significant portion of waste directed to U.S. landfills consists of organic material. In an anaerobic landfill environment, this waste decomposes and releases substantial quantities of methane, a greenhouse gas significantly more potent than carbon dioxide. This process directly undermines efforts to combat climate change, a central objective of SDG 13: Climate Action. Composting offers a critical solution by facilitating aerobic decomposition, a process that drastically reduces methane emissions.

By diverting organic waste from landfills, composting also alleviates pressure on municipal waste management systems. This contributes to the goals of SDG 11: Sustainable Cities and Communities, particularly Target 11.6, which aims to reduce the adverse per capita environmental impact of cities by improving waste management.

Fostering Responsible Consumption and Production Patterns (SDG 12)

Composting is a fundamental practice for achieving SDG 12: Responsible Consumption and Production. It directly supports Target 12.5, which calls for a substantial reduction in waste generation through prevention, reduction, recycling, and reuse. By transforming food scraps and yard trimmings into a valuable resource, composting embodies the principles of a circular economy. Various avenues exist for participation:

• Municipal curbside collection programs.
• Drop-off points at non-profits, farmers markets, and community gardens.
• Fee-based collection services offered by private companies.
• At-home composting initiatives.

Enhancing Terrestrial Ecosystems and Soil Health (SDG 15)

The end product of composting is a nutrient-rich soil amendment that enhances land quality, directly supporting SDG 15: Life on Land. Applying compost improves soil structure and its capacity to retain moisture. This makes the land more resilient against the impacts of climate change, such as droughts, wildfires, and soil erosion, contributing to Target 15.3, which aims to combat desertification and restore degraded land and soil.

A Practical Guide to Backyard Composting

Home composting can be initiated in a space as small as four square feet. The process relies on a balanced recipe of four key components and a managed environment.

Core Ingredients and Process

1. Establish a System: Utilize open wooden bins, rotating tumblers, or a simple free-standing pile.
2. Balance Materials: The compost mixture requires four main ingredients:
   • Water: To maintain moisture.
   • Oxygen: Introduced by turning the pile.
   • Nitrogen (“Greens”): Food scraps and grass clippings.
   • Carbon (“Browns”): Cardboard, dead leaves, and shredded paper.

   A general rule is to maintain a ratio of two to three parts “browns” for every one part “greens”.

3. Aerate Regularly: Turning the pile with a hoe or shovel introduces oxygen, which is vital for the aerobic microbes that drive decomposition and can raise the pile’s temperature to 130-160°F (54-71°C).
4. Monitor for Completion: A well-managed pile can produce finished compost in three to five months. The final product should resemble dark, moist soil, with no discernible original materials.

Materials to Avoid in Backyard Piles

To prevent pest issues and ensure effective decomposition, the Environmental Protection Agency (EPA) advises against including the following materials in standard backyard compost piles:

• Meat, bones, dairy products, fats, and oils.
• Treated wood and glossy paper.
• Pet waste.
• Commercially “compostable” dishware or bags, which require industrial facilities.

Troubleshooting Common Composting Issues

Most problems in composting arise from an imbalance in the core ingredients.

• Dry Pile: If the composting process slows or stops, the pile may be too dry. The solution is to add water or more nitrogen-rich “green” materials. A “squeeze test” can determine moisture: a properly moist handful should leave a coating on the hand without dripping excessively.
• Foul Odor: An unpleasant smell indicates the pile has become anaerobic and is releasing methane, similar to a landfill. This is typically caused by excess moisture or too many “greens.” To correct this, turn the pile to introduce oxygen and add more carbon-rich “brown” materials like cardboard or paper.
• Pest Attraction: An overly wet pile or the inclusion of prohibited materials can attract rodents and insects. Maintaining proper aeration and material balance is the primary preventative measure.

Indoor Composting Solutions: Vermicomposting

For residences without outdoor space, vermicomposting presents a viable indoor alternative. This method utilizes specific species of worms in a contained bin to process organic waste.

• Process: Worms consume the carbon- and nitrogen-rich materials, excreting nutrient-dense castings. This process can be faster than traditional composting, taking approximately three to six months.
• Requirements: The process requires a dedicated worm bin with a tight-fitting lid to keep out light and maintain a controlled environment. Conditions must be carefully managed to ensure the worms thrive.
• Considerations: While effective, vermicomposting can be challenging. If conditions are not optimal, the worms may attempt to leave the bin. It is also important to distinguish this biological process from electric countertop devices, which typically dehydrate food waste rather than creating true compost.

1. Which SDGs are addressed or connected to the issues highlighted in the article?

• SDG 11: Sustainable Cities and Communities

  The article directly addresses urban waste management, a key component of sustainable cities. It discusses the problem of organic waste in U.S. landfills, which are typically located in or near urban areas, and proposes solutions like curbside pickup programs offered by “some local governments” and community composting initiatives often found in cities (“nonprofits, farmers markets and community gardens often fill that gap”).

• SDG 12: Responsible Consumption and Production

  This goal is central to the article’s theme. It focuses on reducing waste generation by changing consumer habits. The article encourages consumers to “curb their environmental impact by composting” and provides detailed instructions on how to do so. This directly relates to sustainable consumption patterns and the management of post-consumer waste.

• SDG 13: Climate Action

  A primary motivation for composting presented in the article is climate change mitigation. It explicitly states that organic waste in landfills releases “a lot of methane, a potent greenhouse gas that contributes to global warming.” Composting is offered as a direct action to “reduce the release of methane,” thereby addressing a key driver of climate change.

• SDG 15: Life on Land

  The article highlights the benefits of compost for terrestrial ecosystems. It notes that compost creates a “nutrient-rich substance that help soil” and makes it “better at retaining moisture, which makes it resilient against droughts, wildfires and erosion.” This connects directly to protecting and restoring land and soil quality.

2. What specific targets under those SDGs can be identified based on the article’s content?

1. Target 11.6: Reduce the adverse per capita environmental impact of cities, including by paying special attention to air quality and municipal and other waste management.

   The article’s entire focus is on improving the management of municipal organic waste, which it identifies as the largest component of what “goes into U.S. landfills.” By promoting composting as an alternative to landfills, the article advocates for a method to reduce the negative environmental impact of cities, specifically the methane emissions resulting from improper waste management.

2. Target 12.5: By 2030, substantially reduce waste generation through prevention, reduction, recycling and reuse.

   Composting is presented as a form of recycling organic waste. The article states that composting “alleviates pressure on landfill space,” which is a direct outcome of reducing the final volume of waste that requires disposal. The promotion of various composting methods (backyard, curbside, community) is aimed at substantially reducing the amount of organic waste sent to landfills.

3. Target 13.2: Integrate climate change measures into national policies, strategies and planning.

   While the article focuses on individual and local actions, composting is presented as a tangible climate change measure. The text frames the reduction of methane—a “potent greenhouse gas”—as a key benefit. This type of grassroots and municipal action is precisely the kind of measure that can be integrated into broader climate strategies to achieve national goals.

4. Target 15.3: By 2030, combat desertification, restore degraded land and soil… and strive to achieve a land-degradation-neutral world.

   The article supports this target by describing how the application of compost improves soil health. Robert Reed from Recology is quoted saying that compost makes soil “resilient against droughts, wildfires and erosion.” This directly addresses the goal of restoring degraded soil and improving land quality.

3. Are there any indicators mentioned or implied in the article that can be used to measure progress towards the identified targets?

• Implied Indicator for Target 11.6: Proportion of municipal organic waste diverted from landfills and managed through composting.

  The article begins by stating, “Most of what goes into U.S. landfills is organic waste.” This establishes a baseline. Progress towards Target 11.6 could be measured by tracking the reduction of this proportion as more households and municipalities adopt composting, as suggested by the availability of “curbside pickup,” “community gardens,” and private company services.

• Implied Indicator for Target 12.5: Amount (tonnage) of organic material composted/recycled.

  While not using the official indicator term “national recycling rate,” the article implies this measurement. The entire “how-to” guide for composting is about turning a waste stream (food scraps, yard trimmings) into a usable product. The success of these efforts would be measured by the total volume or weight of organic waste that is successfully composted instead of being thrown away.

• Implied Indicator for Target 13.2: Reduction in methane emissions from the waste sector.

  The article’s central climate-related claim is that composting helps “reduce the release of methane.” Therefore, a direct indicator of progress is the measured or estimated reduction in methane emissions from landfills due to the diversion of organic waste. The article notes that a compost pile smelling bad is a sign it is “releasing methane, like in a landfill,” reinforcing that proper composting avoids this emission.

• Implied Indicator for Target 15.3: Improvement in soil quality metrics.

  The article points to several qualitative and quantitative indicators of improved soil health. It mentions that compost makes soil “better at retaining moisture” and creates a “nutrient-rich substance.” Progress could be measured by analyzing soil samples from areas where compost has been applied to check for increased moisture retention, nutrient content, and resilience to erosion, as described in the article.

4. Table of SDGs, Targets, and Indicators

Source: newstribune.com