From limnos@chebucto.ns.ca Thu Mar 23 12:02:25 2000 Date: Wed, 8 Sep 1999 17:45:26 -0300 (ADT) From: "S.M. Mandaville" To: "Dr. Tony Blouin PhD (Environmental Specialist- Planning Servs- HRM)" Subject: Re: PO4 (fwd) I am forwarding the following Email I rec'd from Dr. Underwood formerly of NSDoE. He gave me some new info. I knew about the direct aereal deposition, I have been using the 0.173 as well as 0.25 (the older figure from the 1975 Dillon & Rigler model which Hart still uses to this day), but my final calcs are based on Underwood's since it is derived from extensive data. See how close it is to Dillon & Molot's later data based on more extensive sampling and they had 0.184 or so (it is in the synopsis I gave you). But the dust fall is a surprise to me, John says none of the stations (he had several) were in Metro, so I can understand if they are near farms, since localised dust from farms would contribute to 0.295 alone or even more. John also talks of the historical work at Cranberry as well. I went to Dal today and his Honours thesis is not there, and it is not even listed (they have typed lists now). John doesnt have it either. But I did skim through Pierre's thesis. Quite extensive work! ---------- Forwarded message ---------- Date: Thu, 2 Sep 1999 15:16:18 -0400 From: John Underwood To: "S.M. Mandaville" Subject: Re: PO4 I don't have a copy of my PhD thesis. I did find some lecture notes which show that deposition of P. that is total P.... not PO4.....was 17.3 as snow/rain, and 29.5 as dust, for an annual total of 46.8mg P per square metre per year during the period 1976 - 198(2?). Honour's thesis 1971. Comparative water chemistry and plankton studies of lakes in the Halifax-Dartmouth region of NS. The main alga in 1969 was a yellow-brown species of a colonial type that looked very much like Volvox (which is a green alga), although I don't recall the name. The second summer was when the Dinobryon was so profuse. If Blue Greens were there, they were of secondary importance. although nutrient enrichment had affected the lake big time. There is mention of Cranberry lake in the MAPC lakes report. THe data are probably a bit shakey, however. At that time, Pierre Bryon conducted a study of the rate of sedimentation of detritus in Cranberry Lake. It was also a thesis , perhaps MSc, and the field work was done in 1970 I think There was some delay in its completion, but I do recall thumbing through it. Pierre used to live in the bedford area somewhere around the rifle range. He was into computers. I haven't heard of him in quite a few years