An Interview on Carbon Sequestration in India
Wangari Maathai, the Kenyan social, environmental and political activist, once said, “ The environment and economy are really two sides of the same coin. If we cannot sustain the environment, we cannot sustain ourselves.”
This is a statement that is especially true in today’s world.
Recently, I hosted a panel discussion on Carbon Sequestration in India with two researchers from this field. The discussion focused on blue carbon sequestration. Our aim was to raise awareness of its importance in the world today.
The panelists were Dr. Suresh Kumar, Professor of Biological Oceanography and Director of the School of Ocean Science and Technology at the Kerala University of Fisheries and Ocean Studies, Cochin, India and Harishma KM, Research Scholar from the Kerala Forest Research Institute.
The interview:
Here is an excerpt of the discussion:
- Dr. Suresh, what exactly IS carbon sequestration?
Elements on the earth are not in fixed forms and are quite dynamic in their forms. The carbon, nitrogen, and oxygen cycles are examples of this. Elements on the earth keep shifting through forms and organisms. However, large amounts of carbon have stayed fixed in the form of fossil fuels, and stored underground for millions of years. Today, we are drilling these fossil fuels for various purposes. This is having a positive impact on the temperature of the earth. Or, in other words, a negative impact on the general ecosystem of the earth. This excess carbon needs to be stored or parked somewhere. The process of capturing this excess carbon is called carbon sequestration.
- Harishma, green carbon sinks are the carbon absorbed and stored by plants on land, while blue is water-based. Why is it that blue absorbs more?
Blue carbon is stored in the form of sediments inside oceans. So, the majority of the carbon cannot be released as easily as in green carbon sinks due to the deep waters. Blue carbon sinks only make up about 0.2% of the seafloor. Yet, they store more than half of their total carbon in seafloors.
- Dr. Suresh, you have been working in the field of algae for several years now. Could you give us a little insight into your work?
Algae are tiny plants generally occupying columns of water. Because of the vast amount of water, they store far more carbon than land-based animals. This is because they can absorb carbon in all three dimensions. The per hectare production of such plants is 600 times higher than plants on land, due to the same reason. Additionally, the surface area for absorption in algae is much higher. This is because they are such tiny creatures. In the Arabian Sea, about 4.2 billion tonnes of carbon dioxide are trapped every year by algae.
- Harishma, you have been researching the carbon stocks of mangrove forests in Kerala over the past couple of years. Could you give us a little insight into your work ?
My recent paper talks about the biomass of mangrove vegetation in Kerala. My study shows an average of 170 tonnes of carbon trapped per hectare. This is based on six species of mangroves from three study areas. The highest carbon was from the species Avicennia marina. This species is commonly called the white or the grey mangrove. The estimation of the ecosystem stock of mangroves is at around 139.82 tonnes/ hectare. This means the vegetation and soil can store about 530.13 tonnes/ hectare of carbon dioxide.
- Harishma, how did you measure the carbon trapped in the mangroves in your study?
The vegetation carbon stock is measured using allometric equations. This is done by measuring the height and D.P.H (Diameter at breast height) of mangroves. The D.P.H is the diameter of a tree trunk at approx 1.4 meters above the ground. Putting this data in the allometric equations, we it’s biomass. The carbon trapped is about 50% of that biomass.
Meanwhile, the soil carbon stock is assessed by measuring the organic carbon in the soil.
Altogether, the ecosystem’s carbon stock is the vegetation carbon stock and the soil carbon stock.
- What are the challenges faced by researchers in this field in India?
Dr. Suresh: In India, measurements and estimates of carbon absorption were last done in the 1960's. No other large studies have been done ever since. Carbon dioxide levels have increased so much in the past 80 years. Various parameters like temperature and nutrition play their part. And because these studies are so old, we don’t know what the carbon entrapment amounts are today. Additionally, the technology used to measure this on a large scale, today, is not made in India.
Harishma: There isn’t enough data to measure the carbon stock levels in India. Although allometric equations are used to gain the approximate values of biomass, it is not a very accurate value. To gain an accurate value, one needs to cut the mangroves. That is prohibited.
Also, the allometric equations are dependent on earlier carbon stock levels. Which we don’t have. So, I had to use values from Indonesian measurements. Because of this, the equation gave strikingly different values of biomass in different areas. Therefore, the average carbon stock in a region could not be determined.
- Dr Suresh, today we generally relate to things like planting trees. Also, in areas with little space, we’ve also come out with things like vertical gardens. How can we bring the area of blue carbon sequestration into this field and help people become more aware of it? How can ordinary citizens contribute to blue carbon sequestration?
Human intervention is not truly needed for blue carbon sequestration. Research can be done in this area for long term monitoring and estimations. However, from humanity’s side, we should be reducing our pollution levels. This way, the organisms absorbing the carbon can flourish. Then, they can also absorb higher amounts of carbon.
- Harishma, how difficult is it to sequester carbon using blue carbon sinks?
The ocean does most of the work of carbon sequestration in blue carbon sinks. Today, however, we have issues like ocean rise and it’s acidification. Pollution also has a negative impact on the rate of blue carbon sequestration. This is one of its greatest challenges today.
- Dr. Suresh, what are carbon sequestration solutions that can be implemented in the world today?
Solutions would include some sort of aquaculture technology. One that could, both sequester carbon, and produce food. The more carbon absorbed would mean more food…
- Dr. Suresh, what could be possible experiments to demonstrate carbon sequestration?
Experiments could include measuring the amount of carbon sequestered in one day.
Questions from the Audience:
Here is an excerpt of the various questions asked by the audience at the end of the session.
- Most carbon trading solutions recommended today are land-based. What is the potential for carbon trading in the blue carbon area?
Carbon trading in blue carbon sinks and their sequestration has not been tried yet. However, potential exists in this field.
- Where does India stand in carbon sequestration globally? Which countries are taking a lead in this aspect?
Carbon sequestration generally happens quite naturally. In fact, there are countries like Bhutan, which happen to be carbon negative. This is because they have a high forest cover. Today, Bhutan’s forests are not only completely absorbing its entire carbon emissions. They also absorb a certain degree of carbon from both India and China. Additionally, there are a few private companies in Europe and in the US working in this area. They are investing in technological carbon sequestration solutions.
- What are the efforts made by the government in India to promote carbon sequestration?
As mentioned earlier, carbon sequestration generally happens naturally. But, the government is working on promoting green cover. It is also promoting the preservation of reserve forests, and protection of coastlines and marine areas. These are all natural, vital areas for carbon sequestration.
- For the natural absorption of carbon in these sinks, it was that algae was mentioned to be used for this purpose. What are the other organisms in the vast oceans that are also used for this purpose?
Carbon sequestration in blue carbon sinks occurs primarily by oceanic plants. These majorly consist of algae. Most organisms in the oceanic food chain contribute a certain amount to the capture and storage of carbon. But, these are all secondary players in the carbon cycle. The primary carbon sequestration in blue carbon sinks is done by algae and to a certain extent, by corals.
- There was also a cautionary point discussed at this time. When carbon is absorbed by biological means, such as algae, it is eventually used in the form of food or energy. Because of this carbon is once again released. Only a permanent storage solution of this carbon will result in true carbon sequestration.
To conclude:
The objective of this session was introducing and increasing awareness about carbon sequestration. Especially sequestration in blue carbon sinks. The audience in turn are multipliers and can share this concept with their contacts.
Now, more people are consciously aware of this concept. They in turn will keep an eye out for stronger solutions to control carbon dioxide levels.
