Guests - If You want access to member only forums on FM. You will gain access only when you Sign-in or Sign-Up on Fishing Minnesota.

It's easy - LOOK UPPER right menu.

Sign in to follow this  
Followers 0
SKIPPERS KID

Study Finds Nitrates up in lake Superior

1 post in this topic

Study finds nitrates up in Lake Superior

John Myers Duluth News Tribune

Published Thursday, May 31, 2007

The level of nitrates in Lake Superior has increased five-fold over the past 100 years and continues to increase at a steady rate, a University of Minnesota study has found.

The study, published today in the journal Geophysical Research Letters, found that the nitrate isn’t necessarily coming from the expected culprits.

The increase in nitrates has been steady in the big lake, not reflecting the rapid increase in fertilizer and fossil fuel use and over the past 50 years.

RELATED CONTENT

John Myers Archive

“The assumption has been for years that we’re getting atmospheric deposition from agricultural fertilizer and fossil fuel combustion. But the increase in the lake water doesn’t correlate with what is falling from the sky,’’ said Robert Sterner, chief researcher on the project for the University of Minnesota. “The nitrate in the lake can’t be accounted for by what’s falling from the sky.’’

Sterner said it’s unclear where the nitrates are coming from. They could be produced by a natural process in the lake, or from some other source of nitrogen. It’s not coming large amounts di-rectly from urban or agricultural runoff because most of the lake’s watershed is forested, Sterner said.

Most lakes use up their own nitrogen through plants. But with so few plants in Lake Superior, the nitrogen keeps building, Sterner said.

The level of nitrates in Lake Superior now sits at 25 micromolars, up from 5 micromolars in 1906. It would take levels above 700 micromolars of nitrate to be considered unsafe for human drinking water. A micromolar is a concentration of one-millionth molecular weight per liter.

While nowhere near a threat to people, it’s unclear what effects increased nitrates may have on other parts of the ecosystem or why they continue to increase. Sterner and other University of Minnesota scientists plan to look at the relationship of nitrate to Lake Superior’s unusual level of carbon use over carbon production.

Share this post


Link to post
Share on other sites
Guest
This topic is now closed to further replies.
Sign in to follow this  
Followers 0



  • Posts

    • ZachD
      I guess I will have to call the dnr about the couple spots I am in question of. Ones a darn and you can easily pick them off all day almost year round
    • Stick in Mud
      Thanks for the great report.  We fished up there all last week, and we found shiners to be the only bait we *couldn't* get bites on. Very, very strange, but by far our best bite was on crawlers.  I think our total was something like 8 fish on shiners and 80 or 90 on crawlers (between two boats).  We didn't start fishing with crawlers until Thursday, either, so all those fish came on our last two days, with the windier Thursday being best.
    • Dale S
      Thanks guys for the informative replies. Can you also comment on the walleye limits?
    • noska
      Hey Barefoot on the main lake or current areas? 
    • jkrash
      a tournament-record 10-pound, 2-ounce beauty was big fish and A record 110 boats fished this year’s tourney, held out of the marina at Fortune Bay Resort Casino. 492 walleye, another tournament record, were weighed and released at this catch-and-release event.
    • Bowfin
      My daughter is shooting my 12 gauge 870 Wingmaster really good. Im looking for a nice looking, nice shooting and dependable pump shotgun for her at a decent price. I'm not liking the newer 870 Wingmasters as much as I did when I bought mine 30 years ago. I recently saw some Weatherby PA08s. Very nice looking gun which rival the looks of old Wingmasters with walnut stock, deep checkering, fairly light for $350 new. Reviews I see from 2011-2014 have me concerned a bit about hard trigger pull and shells sometimes not ejecting. Anyone have any experience or knowledge about these Weatherby pumps? If there were issues, you would think Weatherby would have fixed them by now.
    • jb426
      I did this a while back.  If you have basic carpentry skills you can do it for under $200. Here's what I did.   Get 2x8 treated board.  Cut to length of back bench.  Attach a swivel seat to board then attach board to back bench using screws and glue.   Buy two sheets of 4x8 3/4" sheeting that's rated for exterior and a gallon of deck stain.  Stain said sheets.  Cut out one for floor and one for casting deck up front (i used the front bench with a little bracing in between).  Use left over 2x8 for bracing casting deck.  You will also need one 2x4 treated board for bracing of the floor.  Install casting seat up front.  Looks good and is cheap and easy.  I used cedar stain and bought cedar colored treated lumber.  If I remember correctly I cut out the middle bench.   Only problem was it added a lot of weight so had to upgrade to 15 horse.  Sold it  a couple of years later for a $100 profit.  Just an idea.  
    • Walleye #1
        Walleyes on Leech Lake found themselves spread out but actively feeding on shiners.  A Jig and shiner or a plastic and lindy rigs with shiners and leeches were the go to presentations during the course of the week.  Somedays walleyes were wanting it dragged along which is where lindy rigs worked well and other days snapping or twitching a jig and minnow was the ticket.  So being diverse in your presentations, changing up colors and cadences, and getting away from the crowds is the ticket.     West End - Fish were found on West Goose Flats, Star Point, Grand Vu Flats, Duck Point, Pine Point, Stoney, and on some of the breaklines in Traders Bay.  Depending on the day depths changed, but it seemed the best bite was in 8-14 feet of water.  Find the shiners and you found walleyes closeby!     East End/Main Lake - Main Lake Rocks are still producing a large quantity of fish in the 20-26” protected slot, with some keepers mixed in.  Annex, Submarine, Five Mile, Pelican Island, and Rogers Point all had decent bites. Fish were typically found in that 8-12ft range on this part of the lake and finding areas with sand and boulders was the key.  Portage Bay also reported a good bite up near Federal Dam.  Look for emergent cabbage in Portage, especially on those bright and sunny days where those walleyes will look to find cover.  Pitching a jig and minnow or jig and plastic for these Leech Lake Walleyes in the cabbage is fun way to catch them.     Jumbo Perch are also showing up with the walleyes, but often times will be shallower.  Found some of our best perch bites in 6-10ft of water, with some really nice jumbos mixed in.     Jason Freed Leisure Outdoor Adventures Fishing Guide Service
    • HugeHogChaser
       Any boat restorers here in the twin cities area?  Looking to get some information and possibly a quote on a 12 foot aluminum boat. Would like benches re-done with carpeting, and possible floor work. Thanks in advance, I appreciate it!
    • HugeHogChaser
      Good evening,   i recently inherited a 12 foot aluminum boat, and I would like to re-do the interior. (Add carpet to the benches, possibly add marine grade plywood to the floor and carpet the floor as well.)   does anybody have any experience doing this, or recommend anybody that is good with this type of thing?    Trying to figure out if it's worth it to pay someone to do it, or try and figure out how to do it myself with no experience.    Anyways, thanks in advance!