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Data Handling :(

Transeau estimated that one hectare (10,000m^2) of his maize field contained 25,000 plants. He dried and weighed several plants at the end of the growing season and so estimated the biomass of his plants as 14,800kg ha^-1. This standing crop of plants was produced from the seed in one growing season so it represents the net primary production. Chemical analysis of the maize revealed that 14,800 kg of the plant tissue was equivelant to 6610 kg carbon. Transeau then measured the respiration rate of maize plants during the night and so estimated the amount of glucose which had been used in respiration and which he had not been able to weigh at the end of the growing season. This gave him a value for R of 5053 kg glucose ha^-1yr^-1

a) If all this carbon were fixed by photosynthesis, why is it equivelant to 16524 kg glucose?

b)Why did transeau have to estimate the respiration rate of maize plants during the night?

c)if 1 kg glucose releases 15790kJ heat energy when it is burnt calculate the NPP in kJ m^-2 yr^-1 and R in kJ m^-2 yr^-1.

d)calculate the GPP for this maize field.

e) Transeau estimated that 2 x 10^6 kJ sunlight fell on each sq metre of his maize field during the growing season. Calculate the % of this sunlight energy which is represented by GPP, NPP and R of the maize crop.

f) Why is so little of the sunlight energy converted into NPP.

Please help if you can!! :frown: