TwY, How did you graduate from college and not know how to measure alkalinity? Or haven't you graduated yet?. If you are still in school check with the Limno prof or someone in the chem department.
No alkalinity is not really needed if yuou are only interested in current productivity estimates. Secchi measurements will provide a current relative estimate of productivity whereas alkalinity will provide a potential for productivity and increased standing crops if and when proper ratios of dissolved nutrients become available. Productivity levels vary throughout the year season by season in natural waters where fertilizer is not intentially addded. Amount of variation is dependant on nutrient budgets and inputs, flora and fauna, and somewhat on alkalinity. It is a complex system which should have been emphasized in limnology / ecology class.
Estimating BG standing crop from productivity estimates or measurements has probably been done; at least overall fish standing crops or maybe forage standing crops have been correlated with producitivity. I do not have these numbers or formulae in my literature files. Get to the science library and do some homework and literature searches. A good placed to start would be searching Aquatic Sciences and Fisheries Abstracts. You have time to do this before the pond is finished. If you find something let me know about it since I provided lots of previous BG info for you.
