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D'><o:p>&nbsp;</o:p></span></p><p class=3DMsoNormal><s This is a multi-part message in MIME format. --------------24DBBAB9BBEDC4CF4723CDC7 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Hi John & All, After a long lapse; getting back to eutrophication. Nutrient rich waters tend to get bad press because, if some limiting element (P usually) becomes high then blooms of usually toxic (always ?) Blue Green algae are likely. They can fix N so, given ample P, grow like weeds then, unlike weeds die, decay etc. But nutrient poor water is also undesirable; crystal clear water devoid of life as in some glacial lakes. As with most matters, a Goldilocks balance is desirable. There was a good article in American Scientist 65(2): 159-170, 1977; The Plant-Animal interface in// Freshwater Ecosystems; Karen Glaus Porter and by good luck I found it. I was especially impressed by "In periods of peak zooplankton abundance....the grazer community filtered the entire volume of water in a eutrophic (nutrient rich) lake as many as 4.69 times (469%) during one day." This was measured using C14. And yes the fertilized and mowed lawn right down to the water is an effective way to mess up a lake. But nothing kills a small lake, with small water flow, as efficiently as year round houses and septic tanks. YT, DW, Kentville YT, DW, Kentville On 5/28/2020 5:24 AM, John and Nhung wrote: > > I followed the link, and it does look interesting. > > I predict that eutrophication will be a growing problem here, as well, > if summers get hotter and drier and predicted (Dare we say … as being > experienced?”) Our studies down here in God’s country over the years > have been showing a positive relation between rainfall and water > colour (which can be translated as dissolved humic material). When > rainfall is low, colour levels drop, and lakes appear susceptible to > blooms at lower levels of nutrient. Kinda makes sense: light > penetration is greater when colour is lower and some of those organic > molecules may react with nutrients. > > We suspect phosphorus of being a greater problem that nitrogen in our > lakes, but the idea is still interesting. > > In the meantime, lake and river front property owners can help by > leaving their shorelines the blazes alone. Wild shorelines do a great > job of absorbing nutrients and runoff, thereby controlling turbidity, > as well. Folks, those nice lawns going all the way down to the lake > are a terrible idea, especially if you fertilize them! > > Something else to worry about: The science of cyanotoxicology is > evolving, but they keep discovering a growing number of very nasty > toxins in blue-green algae. The effects they have on us humans > varies, but the mix includes carcinogens and some neurotoxins, for a > start. > > Public education helps, and so do municipal by-laws. But a lot more > education is needed, and we need PROVINCIAL regulations to control the > fun and games still being played on lake shores. Regulations with > consequences for both contractors and property owners. > > I could write a lot more but for God’s sake, keep lake shores wild! > > *From:*naturens-owner@chebucto.ns.ca > [mailto:naturens-owner@chebucto.ns.ca] *On Behalf Of *N Robinson > *Sent:* May 27, 2020 8:48 PM > *To:* naturens@chebucto.ns.ca > *Subject:* [NatureNS] Winning submissions to Biomimicry contest for Youth > > > "*Only* in the *U.S.A.*, you say? Pity..." > > https://mailchi.mp/biomimicry/2020ydcwinners?e=9bfd59afac > > 3rd place, /The Bay Protector/, may be of interest - dealing with > eutrophication. > > Nancy > --------------24DBBAB9BBEDC4CF4723CDC7 Content-Type: text/html; charset=utf-8 Content-Transfer-Encoding: 8bit <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> </head> <body> <p>Hi John & All,</p> <p> After a long lapse; getting back to eutrophication. <br> </p> <p> Nutrient rich waters tend to get bad press because, if some limiting element (P usually) becomes high then blooms of usually toxic (always ?) Blue Green algae are likely. They can fix N so, given ample P, grow like weeds then, unlike weeds die, decay etc.</p> <p> But nutrient poor water is also undesirable; crystal clear water devoid of life as in some glacial lakes. As with most matters, a Goldilocks balance is desirable.<br> </p> <p> There was a good article in American Scientist 65(2): 159-170, 1977; The Plant-Animal interface in<i> </i> Freshwater Ecosystems; Karen Glaus Porter and by good luck I found it. <br> </p> <p> I was especially impressed by "In periods of peak zooplankton abundance....the grazer community filtered the entire volume of water in a eutrophic (nutrient rich) lake as many as 4.69 times (469%) during one day." This was measured using C14. <br> </p> <p> And yes the fertilized and mowed lawn right down to the water is an effective way to mess up a lake. But nothing kills a small lake, with small water flow, as efficiently as year round houses and septic tanks. <br> </p> <p>YT, DW, Kentville<br> </p> <p> <br> </p> <p>YT, DW, Kentville<br> </p> <div class="moz-cite-prefix">On 5/28/2020 5:24 AM, John and Nhung wrote:<br> </div> <blockquote type="cite" cite="mid:002d01d634c9$6b75ee50$4261caf0$@eastlink.ca"> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> <meta name="Generator" content="Microsoft Word 14 (filtered medium)"> <style><!-- /* Font Definitions */ @font-face {font-family:Calibri; panose-1:2 15 5 2 2 2 4 3 2 4;} @font-face {font-family:Tahoma; panose-1:2 11 6 4 3 5 4 4 2 4;} /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {margin:0cm; margin-bottom:.0001pt; font-size:12.0pt; font-family:"Times New Roman","serif";} a:link, span.M