#meromictic lake

[wildflowers-of-southern-ontario]

Crawford Lake

Crawford Lake is meromictic, meaning its layers do not mix. (Another meromictic lake is McGinnis Lake at the Petroglyphs Provincial Park.)

According to Conservation Halton's website, "In the deepest part of the lake 75 ft below the surface, sediment is deposited in annual layers and remains totally undisturbed. Scientists researching this sediment in the early 1970s discovered corn pollen dating from the 13th to 15th century. This led to the discovery of the archaeological footprints of a Wendat or Attawandaron village."

Photograph taken on July 30, 2023, at Crawford Lake Conservation Area, Milton, Ontario, Canada.

[spookymechafoxmoth]

[proteusolm]

Nooo. The proposal to officially declare Earth to be in the Anthropocene Epoch as evidenced by sediment samples from a rare meromictic lake in my area has been voted down. It feels wrong and somehow unscientific that something so huge and important hinged on the judgement of only 16 people.

[anerea-lantiria]

So now I’m curious:

What are the Three Big Lakes of Africa?

Signed,

Geographically-challenged American 😆

Tee hee! Thanks for being curious!

So the Maziwa Makuu, known as the African Great Lakes, all lie within the tropical zone along the Great Rift Valley in East Africa. Collectively they contain a quarter of the world's fresh unfrozen surface water and about a tenth of the world's species of fish.

The largest is Nyaza (Lake Victoria), second largest in the world by area after Superior. It's the primary source of the White Nile and is surrounded by Kenya, Tanzania, and Uganda.

Next is Lake Tanganyika, the longest lake in the world, the second largest by volume and, at a depth three and a half times that of Superior, it's also the second deepest. Its youngest basin has been around for over 3 million years and its oldest for around 10. (Lake Baikal in Siberia is the deepest, biggest by volume, and oldest.) Tanzania, DRC, Zambia, and Burundi share it, although it probably laughs at the notion of nations.

Lake Malawi is the third by area, although second by depth (almost twice as deep as Superior) and is another ancient lake. It is alkaline and also meromictic, so the upper and lower waters don't mix. It contains the most species of fish of any of the world's lakes, and as the water is remarkably clear and averages 80°F at the surface, it's fantastic for snorkling and diving. Tanzania also borders this lake, along with Malawi and Mozambique.

:)

(Oh, and although not one of the Great Three Lakes, Turkana is in the Rift Valley System and I'd forgive you if you remember it as Lake Turukáno. In fact, I'll be impressed if its remembered at all!) 😉

[council-of-beetroot]

Ever just think about how fucking cool jellyfish are?

And meromictic lakes those are fucking cool as well

[yarnings]

We went out to Crawford Lake the other day (if that names sounds familiar to you it was in the running as a site for a marker for the start as the anthropocene). If you're going to go, I highly recommend getting the Lake to Longhouse tour. At the end of the tour, our guide took us down to the lake, and explained about it being a meromictic lake, and how that led to the undisturbed sediment layers. There's apparently only 13 in Canada (makes sense, after all it's a special quality of the lake, not something common) and 50 in the entire world.

Hold up here. I know we have a large landmass, but we have 1/4 of the (known) meromictic lakes in the world??? I know that other countries just don't have a lot of lakes (my my standards), but that's got to be a case of them just not finding them, right? (Although... if you live in a sufficiently temperate climate do lakes mix at all? Does it not count as a meromictic lake unless you live somewhere that gets cold enough that you'd expect the lake to turn over twice a year?)

[biking-the-erie-canal]

Camillus to Canastota

Camillus is synonymous with hills to me! We had the big hill up to the Nightshade Inn & Gardens yesterday (which was fun going down this morning) and more hills on the other side of Camillus as we headed east toward Syracuse. Camillus has a cute Old Erie Canal Park that we passed soon after we got back to the trail. We also saw the Nine Mile Creek Aqueduct early in our day.

We passed the state fairgrounds near Syracuse. It ended Sept 4th, but it had been going in full force as we passed it on the train last Thursday. There was actually a train stop there.

As we came into Syracuse, we had a nice view of Onondaga Lake and the Inner Harbor (no picture).

The bridge got us over the train tracks. I got a photo op and Rob got a train - win-win.

The ride through Syracuse was pretty easy. We went through the lake front area and what felt like the middle of town with some cute restaurants (right along I-690). We didn’t stop other to run into a bike shop on the east side of town. Too late for breakfast and too early for lunch. The ride on the east side of Syracuse was interesting with the trail in the median of a fairly large roadway. It had lots of stops to navigate the traffic, but at least it had bike signals to get us through safely.

We did take a detour today to the Green Lakes State Park. There are 2 glacier formed lakes that are an amazing blue green color. I read it is that color because of the high amounts of calcium carbonate in the water. We ran into a couple on the trail today, and they explained that it is very unusual lake because it is a meromictic lake, meaning it has no seasonal lake mixing. We rode our bikes around the lake, and it was just gorgeous. At one end they had a “beach” and swimming. The swimming looked refreshing, but the beach was …. dirt.

Over 43 miles with the detours. Forgot to mention that the last 20 miles or so today was in the Old Erie Canal State Historic Park. The trails were great and well maintained.

[safereturndoubtful]

Day 84 - to forest at the south of Lake Pavin

The mountains as one looks to the south from Col de Serre, are the remnants of r Volcanoes of Cantal, the largest stratovolcano or conical volcano of Europe, which was formed from 13 million years ago and last erupted approximately 2 million years ago.

This morning, after three days here, I was reluctant to leave them. I went out expecting to be less than an hour, and we were out for double that. Once on the grassy ridge above, the view was uninterrupted for the first time, and it was impossible not to linger. Roja is a big fan of those tiny tarns, or lochans, found high up on mountain plateaus. His favourite, where he likes to go for his birthday, is on High Street, just before High Raise. We found another today, and while I lingered, savoured and pondered the skyline, he took to the waters, or the lido as we say in the Lakes.

We drove on to the north for 45 minutes to another area with remaining evidence of the volcanoes, around the ski area of Besse, where there are several crater lakes, the most scenic and visited being Pavin, which gives its name to a cheese also. Lake Pavin is a meromictic lake, one in which the layers of water do not intermix, as opposed to the more usual, holmictic lakes, in which at least once a year, the surface and deep waters mix. My pictures don’t do it justice, but the colours, shades of green and blue, are very different to what would be expected. Along with a French couple, I stood watching a two foot long Arctic Char saunter about in the shallows just after Roja had retrieved a stick, he must have awoken it from a slumber.

The circuit of the lake is only about three kilometres and popular, even today. I extended it a bit, and took in the peak, Puy de Montchal, at 1407 metres, which gave some excellent views. There was some cloud today, but quite a bit of sun also, though the temperature never got above 10C. This time last year I was in a heatwave in the Vosges, not that far from here.

We haven’t moved far from the big car park at Lake Pavin. Quite a few motorhomes were staying put there, but it was only just off the main road, which was noisy. We took some minor roads and tracks into the forests at the south side of the lake and found an isolated forest pull-in. It did have the first mosquitos thought of this spring, quite surprising with the temperature, though I guess after all the rain we have had. They seemed to like the late afternoon best also, as at dusk, with the temperature lower again, they were nowhere to be seen.

[carbombrenee]

Outside - Crawford Lake Conservation Area, Halton, ON

[fullmetal-optimists]

Hiked around on an escarpment overlooking a small valley and a trail around a lake the other day. The lake I got to see is classified as a meromictic lake, which is a somewhat rare type of lake. Due to their incredible depth they are separated into 3 distinct layers usually with the bottom most layer being almost entirely anaerobic, which is really only suitable for the purple sulphur bacteria that dwell there. The lake has no seasonal turnover, so none of the layers ever gets mixed, meaning there's little disturbance aside from the microbes that live there, and organic material that falls into the depths. This means that whatever falls in and settles there, stays there, which has played an important role in determining the geologic history of the area. In the case of this lake, grains of corn pollen were observed in a core sample of the lake bed at around the 1600's mark, which indicated the presence of an indigenous settlement in the area at the time. This led to a further investigation in the surrounding area and they were able to find various tools, weapons, pottery, etc.

[wildflowers-of-southern-ontario]

McGinnis Lake, Petroglyphs Provincial Park

McGinnis Lake is a meromictic lake, in which the layers of water (i.e., surface, deep, and between these two) do not intermix.

Photographs taken on June 20, 2023, at Petroglyphs Provincial Park, Woodview, Ontario, Canada.

[spookymechafoxmoth]

[spackhuggare]

Alatsee in Germany. Photo taken by me. Found this interesting stuff on wikipedia: “Alatsee is a meromictic lake (which has layers of water that do not intermix). Many divers have died or disappeared mysteriously in this lake due to the  toxicity of the organisms living in this lake. These organisms create the "blood cloud "  that occurs quite abundantly throughout the year.”

[proteusolm]

Thinkin’ about meromictic lakes on this fine Sunday night.

[yellowhearther0]

Hi! I have a fun fact for you:

Did you know lake baikal is the oldest, deepest, and clearest lake in the world? It was formed from tectonic movements in the earth's crust. It's what's known as a meromictic lake, meaning there's a layer at the bottom that doesn't mix with the rest of the water. It's water is so clear there's a telescope set up in the lake to study neutrinos!

oh?? thats so cool actually omg :D

[familyadventuresinnewyorkstate]

🥾𝙀𝙓𝙋𝙇𝙊𝙍𝙀 𝙉𝙀𝙒 𝙔𝙊𝙍𝙆 Meromictic lakes are quite rare and one of the distinct things that set Green Lake and Round Lake apart from other lakes in New York State (and makes them the unique greenish color.) Learn more about visiting here: https://familyadventuresinnewyorkstate.com/green-lake-state-park-manlius-new-york/ #greenlakestatepark #meromicticlake #lake #newyorkstateparks #green #reef #amazingplaces #hiddengem #kayaking #camping #mustvisit #mustsee #uniqueplaces #summer #summerfun #hiking #hike #trails #explorenewyork #cny #centralny (at Green Lakes State Park) https://www.instagram.com/p/Cg2NimDuzsC/?igshid=NGJjMDIxMWI=