▶ Your Answer :
The reading passage contends that carbon
sequestration which involves storing CO2 can be reduce atmospheric CO2. On the
other hand, the lecturer brings up several points to contradict this argument.
First, the lecturer argues that an increase
in the amount of phytoplankton by adding iron to oceans is unlikely to reduce
CO2. This is because the population of phytoplankton is not increased
permanently. When phytoplankton run out of nitrogen, their population is
decreased again. Also, study showed that phytoplankton can absorb very little
amount of atmospheric CO2, by three percent. This casts doubt on the reading
passage’s claim that injecting iron-rich dust to oceans will help to increase phytoplankton
population, increasing the amount of CO2 kept in the oceans.
Second, according to the lecture, creating artificial
wetlands is ineffective. The reason is that study found that artificial
wetlands can store less amount of CO2 than natural wetlands by 23%, although natural
wetlands can absorb CO2 a lot. In addition, it takes too long for artificial
wetlands to be fully developed. This refutes the reading passage’s arguments
that creating artificial wetlands can reduce atmospheric CO2 greatly.
The final points made by the lecturer is
that storing CO2 in abandoned coal mines is problematic. When CO2 meet coals,
methane is released. Because methane contains CO2, it also can emit CO2 when it
is burnt. Also, not all CO2 is attach to coal, leaking out coal mines.
Therefore, it is not useful to reduce CO2. This counters the reading passage’s
assertion that abandoned coal mines could store and reduce CO2. |