Kaziranga National park is a net carbon emitter, climate change may make it worse 

A study conducted by Indian Institute of Tropical Meteorology, Pune and some universities has found it to be a net carbon emitter. 

How was the study conducted? 

Sensors and instruments were installed to monitor carbon dioxide levels, water vapour concentrations, wind speeds and directions. This was done under the MetFlux India project sponsored by the Union Ministry of Earth Sciences. 

All the information from various sensors was analysed using a technique called Eddy Covariance Measurement to see that how much carbon dioxide the trees in the forest were able to absorb or release during various seasons of the year. 

Why this phenomenon is different from usual? 

Forests usually absorb more carbon (through photosynthesis) than they release, which makes them carbon sinks, and they are globally promoted to counter the carbon dioxide emissions from different human activities.  

A similar analysis of the teak forests in Madhya Pradesh by showed that the forest acted as a carbon sink, showing the uniqueness of the Kaziranga National Park ecosystem. 

Why is Kaziranga a net carbon emitter? 

Kaziranga National park is a deciduous forest situated in Assam and home to the largest-population of the one- horned rhinoceros in the world.

The biggest factor that makes Kaziranga national park a net emitter is its unique soil. The soil is home to a large population of bacteria that release carbon dioxide as they breathe, which adds to the carbon dioxide being emanated by other organisms, including trees.  

The photosynthetic activity of trees during the monsoon decreases due to increased cloud cover. Hence, the ability of the forest to absorb carbon dioxide also decreases. The situation remains the same during the post-monsoon and winter months, making the forest a net carbon emitter. 

Why global warming would further reduce the capacity of the forests in the region to absorb carbon? 

At many places in North East India, trees release a large number of heavier isotopes in the water through a process known as transpiration. 

The scientists analysed the isotopes in the transpired water and observed a strong link between the water and carbon cycles of the forest and that the transpired water is one of the causal factors for rainfall locally. 

They also witnessed a decreasing trend in the rainfall coming from the transpired water in the pre-monsoon months, which are responsible for the highest carbon absorption. This will be a major issue as the planet warms further and rainfall becomes more erratic. 

Source: This post is based on the article “Kaziranga National park is a net carbon emitter, climate change may make it worse” published in Down to earth on 9^th Feb 2022.