- What is a Positive feedback loop?
- Climate crisis and Land Degradation
- How to remove carbon?
- Failed effort of REDD+
- Suggestion: New Sink Mechanism
- IT’s Input
- What is carbon sequestration?
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What is a Positive feedback loop?
- It is a process where changing one quantity changes the second one, and the change in the second quantity, in turn, changes the first.
- Desertification, melting of the Arctic ice, the large-scale release of methane from methane hydrate lying on the sea and ocean floors are examples of Positive feedback loop.
Climate crisis and Land Degradation
- Soil is one of the largest repositories of carbon in earth as there is three times more carbon in the soil than in the atmosphere.
- The emissions of soil carbon to the atmosphere is contributing to global warming.
- CO2 emissions from land degradation is about 50 per cent higher than the total CO2 emissions of India, the third-largest emitter in the world. So, land degradation is a significant contributor to the climate crisis.
- Land degradation is responsible for annual global emissions of 10 to 12 per cent of the total emissions.
- On the other hand, the climate crisis is further speeding up desertification by increasing the frequency and intensity of droughts, floods and forest fires. Hence, Climate crisis and desertification are reinforcing each other.
How to remove carbon?
- The best way to remove carbon is by sequestering it in its natural sinks which are forests, grasslands and soil.
- In other words, there is need for rapid enhancement in the capacity of natural carbon sinks to suck atmospheric carbon. This is also required to combat desertification.
- To curb desertification, there is need to restore degraded soil via forestry, improving vegetative cover, enhancing water use efficiency, reducing soil erosion and adopting better farming systems.
Failed effort of REDD+
- In 2007, REDD+ (Reducing Emissions from Deforestation and Forest Degradation) was formalized to incentivise forest conservation in tropical developing countries by providing them funds and allowing them to sell carbon credits to the developed countries.
- However, currently, there is no convincing evidence to establish its contribution to reversing deforestation trends.
- The developed countries’ funding commitments for REDD+ have also been much lower than expected.
Suggestion: New Sink Mechanism
Owned by communities
- Any land and forest-related mechanism will work only if it is owned by communities.
- Studies show that indigenous people and local communities are capable of achieving excellent forest conservation outcomes by investing only a fraction of the total money spent on conservation by all agencies.
Carbon sequestration-plus approach.
- The mechanism, to address carbon removal and land degradation, has to be a carbon sequestration-plus approach.
- In other words, improved sustainable forest and farm management practices have to be the basis of this mechanism. This will lead to social, economic and ecological benefits.
- Scaling of carbon sequestration would be one of its co-benefits.
- Land and forest-based mechanisms cannot be sustained on carbon credits. These cannot be left to the mercy of the markets, and a non-market approach is needed to finance them.
- Hence, there is need to design a non-market mechanism where funds are mobilised to build the capacity of communities and local governments.
- Based on their performance, they can be rewarded for developing their own ‘sink’ and for achieving emissions reduction and carbon stock enhancement.
Combination of domestic and international resources
- Any global mechanism cannot depend solely on international funding.
- REDD+ experience shows that once foreign funding ceases, projects become unsustainable.
- So, funds for the Sink Mechanism have to be a combination of domestic and international resources to build domestic ownership.
- The Intergovernmental Panel on Climate Change’s (IPCC) Special Report on Global Warming of 1.5°C makes it clear that we cannot meet the target of 1.5°C without large-scale “carbon removal” from the atmosphere.
- The REDD+ mechanism effort has failed, but the lessons learnt can be used to design a new global mechanism to enhance natural carbon sinks.
- An analysis of the submitted Nationally Determined Contributions (NDCs) udner Paris agreement reveals that more than 100 countries have focused on the land use, land use change and forestry (LULUCF) sector under their climate mitigation strategies.
- What we now need is to bring all the countries together and agree on the Sink Mechanism as a true collaborative mechanism to fight the climate crisis.
What is carbon sequestration?
- Carbonis found in all living organisms and is the major building block for life on Earth.
- Carbon exists in many forms, predominately as:
- Plant biomass, soil organic matter, and as the gas carbon dioxide (CO2) in the atmosphere and dissolved in seawater.
- Carbon sequestration is the long-term storage of carbon in oceans, soils, vegetation (especially forests), and geologic formations.
- Oceans store most of the Earth’s carbon.
- But the soils contain approximately 75% of the carbon pool on land.
- This is three times more than the amount stored in living plants and animals.
- Therefore, soils play a major role in maintaining a balanced global carbon cycle.
- Soils contain more carbon than is contained in vegetation and the atmosphere combined.
- Agricultural carbon sequestration has the potential to substantially mitigate global warming impacts.
- At the same time, employing methods to enhance carbon sequestration in soil will increase soil quality.
How is Carbon Sequestered in Soils?
- Through the process of photosynthesis, plants assimilate carbon and return some of it to the atmosphere through respiration.
- The carbon that remains as plant tissue is then consumed by animals or added to the soil as litter when plants die and decompose.
- The primary way in which the carbon is stored within soil is as soil organic matter (SOM).
- SOM is a complex mixture of carbon compounds, consisting of decomposing plant and animal tissue, microbes (protozoa, nematodes, fungi, and bacteria), and carbon associated with soil minerals.
- Carbon can remain stored in soils for millennia or be quickly released back into the atmosphere.
- Climatic conditions, natural vegetation, soil texture, and drainage all affect the amount and length of time carbon is stored.
Methods that significantly enhance carbon sequestration in soil include
Conservation tillage (low till / no-till farming)
- It is the process of minimizing or eliminating manipulation of the soil for crop production.
- This includes the practice of mulch tillage, which leaves crop residues on the soil surface.
- These procedures generally reduce soil erosion, improve water use eﬀiciency, and increase carbon concentrations in the topsoil.
- Conservation tillage can also reduce the amount of fossil fuel consumed by farm operations
- It is the use of crops such as clover and small grains for protection and soil improvement between periods of regular crop production.
- Cover crops improve carbon sequestration by enhancing soil structure, and adding organic matter to the soil.
- The process of planting diﬀerent crops on a rotating pattern of years (e.g. corn-oats-clover).
- It will reduce the loss of carbon from the soil and with some additions (e.g. manure- lime-phosphorous) will add carbon to soils.
- All of the methods above are more widely used in organic farming than in conventional farming. Carbon stored in soils oxidizes rapidly.
Benefits of Soil Sequestration of Carbon
- Removing CO2 from the atmosphere is only one significant benefit of enhanced carbon storage in soils.
- Improved soil and water quality,
- Decreased nutrient loss,
- Reduced soil erosion,
- Increased water conservation, and
- greater crop production may result from increasing the amount of carbon stored in agricultural soils.