Dear Anila,

the question with primary production isn't so simple.  You have to do with alive system and photosynthetic activity of algae depends on a lot of factors of surroundings. E.g, in the Carpathians streams, brooks and  small rivers smthms appear that the highets primary productivity (in benthos and periphyton) appears in the Winter time! (Look, please, my page). In plankton also would be blocking of the development by intensive sun rays... So, should take into consideration the deeper layers, as we have to do with the effect of redistribution of production in the column.

The very interesting question is water transparency influence. We have some theoretical elaborations in this question.

As well you should know that net productivity is approximation closely related with science fiction! DIFFERENCE BETWEEN PRODUCTION AND WHAT DECOMPOSITION? What method of determination of decomposition - on oxygen, on balance of carbon??? Anaerobic metabolism can be very high in shallow waters esp with the higher aquatic vegetation! It can differ several times

Plankton is only subsystem and important is productivity in total or General productivity of the ecosystem, and this is connected with redistribution of primary productivity of plankton (depends on depth of the system - what "net" productivity of the deap sea area? So, we can speak about balance of subsystems, budget etc.

So, the answer can be: you have to do with the more eggective functioning of the sytem of pl comm in mooson perion. As well can be better situation with biogens...

Andrey

Dear Ms. Vijayan, What about the chlorophyll level during monsoon?.  Land run off  during  monsoon season  is very high and this induces multiplication of microalgae which can reflect in higher rates of NPP and GPP during monsoon.  Another  explanation  for this can be the result of deck incubation and not  in situ incubation of sample bottles.   Correlating  NPP and GPP values with cell density, chlorophyll levels and dissolved nutrients  can give possible explanation. Best of luck.  kaladharan

Thank you Dr Andrey and Dr Kaladharan.

Dear  Dr Andrey, There are possibilities of rainwater inflow and mixing of organic wastes from animal cages even though the zoo officials claim there is separate channels for waste disposal. A huge population of bats are found along the trees throughout the year. Their faeces are a source of nitrate and phosphate. 

I read the lake morphology is also an influential factor for primary production. 

If nutrients are playing important role in productivity, how CR varied in season. 

Dear Dr Kaladharan, Sir I have followed Winkler's method only in determining the productivity. 

& I couldn't understand deck incubation and in situ incubation.

Thank you

Anila Ajayan

Yes, deck incubation  means incubation of sample bottle  to light in the deck of a vessel or in your case shore/ lab.  In situ incubation  is  incubating the sample  bottles  for  certain hours in the lake water at appropriate depth.

NPP depends primarily on the microalgae present in the system. As leaching of nutrients is maximum during monsoon, there is every chance that NPP and GPP reach the maximum. All other factors complement this.

Thank you Dr Kaladharan for the clarification. 

Dr Fr Jose John, Thank you for the answer. It would be nice if I get some reference paper if possible. 

Thank you

There is not much that I can add to the remarks of the other colleagues. Except for the possibility that there is a formidable photoinhibition (excess solar radiation) during the pre-monsoon; and that solar radiation (UV) does not only inactivate algae, but also inhibit bacterio- and zooplankton that may be included in the bottles. I have no idea what the impact of grazers (like copepodes and cladocerans) has been in your enclosures. But these are factors that influence the outcome of GPP, NPP and RESP. Greetings jan  

Thank you Dr Jan. 

Good Day !