The impact of climate change on rates of photosynthesis

[KeenTeen17]

I am doing research for a project and was wondering about The impact of climate change on rates of photosynthesis

thanks

[ceterach]

Hi KT

It is generally assumed that under normal conditions CO2 is the rate-limiting step in the process. Therefore increased CO2 in the atmosphere will increase the rate of photosynthesis. If you put "rate-limiting step in photosynthesis" into google you will get all the info you need.

All the best

John

[CapAndBracket]

Originally Posted by KeenTeen17

I am doing research for a project and was wondering about The impact of climate change on rates of photosynthesis

thanks

Hi KT, that is a big subject, and i don't know how far you are expected to go with it but here's my take.

CO2 can certainly be a limiting factore and increasing it's level in wel lit and watered glass houses increases phototsynthasis (food output).

I think for a project on climate change you need to disscus plus and minus effect for CO2, temperature and available light.

Increased CO2 could scatter more incoming sunlight so reducing the amount of all or some frequencies that get through.

Climate change involves temperature, here increased temperature may well increase the growing season so amount of potential photosynthesis increased, but the chemical route involved in photosynthesis involves proteins that have a temperature limit (they denature above their max opperating temp and stop working), so increased temp or sunlight (or CO2) would be of negative value in the Sahara, (and such areas may well increase in area).

Land mass!, some algae and lichens grow on ice sheets, climate change could see these shrink (the land below them is small in comparison area wise), so shinking ice sheets and rising sea levels could reduce the area available for plant growth, having said that the algal blooms (base of sea food chain) could boom and actually do more photosynthesis than the species on areas lost.

Just a few idea's, it really is a fascinating subject.

Cheers J.P.

[annes]

Originally Posted by KeenTeen17

I am doing research for a project and was wondering about The impact of climate change on rates of photosynthesis

thanks

Global change will definitely have big changes in agricultural ecosystems that will affect photosynthesis and plant productivity. However, the effects on plants will be different for each region depending on the pre-existing climatic conditions and the adaptation potential of local cultivated species. In Crete, an island with typical Mediterranean climate, high temperatures and lack of rainfall during summer are the most important factors determining productivity of tree crops. Therefore, cultivated species in Crete, and the Eastern Mediterranean region in general, will have to grow in a hotter, drier and, in some cases, more saline environment.
More info goes on google.


Water Resources: PX Pressure Exchanger

[PeterJL]

The reaction will surely depend on the partial pressure of CO2, the temperature and since it is a photo reaction, the light intensity (which begs questions about which part of the spectrum).

So at constant temperature, standard light intensity and range of frequencies there may well be a clear dependence on partial pressure of CO2 but I would have thought that the increase in pCO2 will be very small.

I wouldn't like to have to devise an experiment where you kept the other variables constant while measuring changing reaction rates by varying p CO2 and measuring say p O2 changes.