3 ms·

Perhaps i'm missing it; I don't see any discussion of "flow". My uneducated definition is based on flow though the water body: a "pond" is mostly static, with n

Perhaps i'm missing it; I don't see any discussion of "flow". My uneducated definition is based on flow though the water body: a "pond" is mostly static, with no outflow, and a "lake" has as much outflow as inflow most of the time. I spent a few years building ponds and lakes and levees and dikes and such in association with people who had spent entire careers doing so. That was the "common wisdom" opinion. There's been considerable legal fuss over the question of "how wet does land have to be, for how long, to be 'waters of the United States' for the purposes of regulation."

cyanydeez 4y ago
Right, everything you mentioned is a hydrodynamic world. The paper is more concerned with whether the body of water provides a ecological service rather than a hydrodynamic.
- RajT88 4y ago
  And there is greater variance still in what counts in the real estate world as "Waterfront Property".
  - smegsicle 4y ago
    'pondfront' with a dam maintained by animatronic beavers
kickaha 4y ago
Subtle point (addressed in the first sentence of the paper proper). “Lentic” bodies of water, those discussed here, means “still.” Presumably this means flux below some threshold.
D13Fd 4y ago
That doesn’t seem right, or I’m missing something. If I dam a stream and create a 12’ diameter pool, but the incoming water flows over the spillway, that’s a lake?
- xattt 4y ago
  Yes! Lake Tamblyn at Lakehead University is one such small-diameter artificial “lake”. Of course, to confuse matters, a lake becomes a pond if damming was done by beavers. (1) https://goo.gl/maps/pwescdqRHeEAgrr37 https://goo.gl/maps/pwescdqRHeEAgrr37
- brasic 4y ago
  Definitely. See Lady Bird Lake or Lake Travis in Austin: basically just parts of the Colorado River.
  - thaumasiotes 4y ago
    Lake Travis might be better characterized as a river, but if we call it a lake that still has nothing to do with the objection in your parent comment. Lake Travis's surface area is 19,000 acres. A 12'-diameter pool cannot be called a "lake" because it is far, far too small to qualify. Inflow and outflow don't enter into it. Note that by the proposed definition, all rivers and all segments of any river are lakes; outflow is always equal to inflow for any persistent body of water. Personally, I'd be more comfortable choosing whether to call Lake Travis a "river" or a "lake" based on whether there's a current on the surface. If yes, it's a river. If not, why not call it a lake.
bipson 4y ago
As mentioned below, every standing water has (on average) the same amount of inflow as it has outflow, otherwise it wouldn't be there in the first place ("dry up", evaporate, etc.) In fact, I know an artificial pond (and I guess there are many) that has no obvious inflow, but if you look closely and feel the waters 1-2 m below the surface, you realize it has massive inflow from ground-water (there is a large river just nearby), and there is a swampy area at the opposite end, where the pond has considerable outflow - just not as obvious. Now we could modify this to say, there must be obvious inflow from a river, stream or similar... But then again, in areas where there are not many big lakes nearby, e.g. Lower Austria, there are several "lakes" (often artificial) which I always jokingly criticize ("You call that a lake?"). If you grew up near e.g. Lake Constance or let's say Lake Michigan, most "lakes" are ponds for you, even if they have inflow. So I think most people would agree that surface area is the main differentiator, but I would say it is highly subjective where you draw the line.
- thaumasiotes 4y ago
  Large bodies of water with inflow from groundwater were a major cultural feature in India: https://en.wikipedia.org/wiki/Stepwell https://en.wikipedia.org/wiki/Stepwell Major groundwater engineering projects were also used in early Mesopotamia to inhabit otherwise unlivably dry areas. You'd dig a series of wells between the site and a mountain, with a tunnel connecting the bottoms of the wells. Water collected in the wells and flowed down the tunnel to the village.
- gs17 4y ago
  > If you grew up near e.g. Lake Constance or let's say Lake Michigan, most "lakes" are ponds for you, even if they have inflow. Definitely, to me it's not really a lake if you can see the entire opposite shore.

cyanydeez 4y ago

Right, everything you mentioned is a hydrodynamic world. The paper is more concerned with whether the body of water provides a ecological service rather than a hydrodynamic.

RajT88 4y ago
And there is greater variance still in what counts in the real estate world as "Waterfront Property".
- smegsicle 4y ago
  'pondfront' with a dam maintained by animatronic beavers

kickaha 4y ago

Subtle point (addressed in the first sentence of the paper proper). “Lentic” bodies of water, those discussed here, means “still.” Presumably this means flux below some threshold.

D13Fd 4y ago

That doesn’t seem right, or I’m missing something. If I dam a stream and create a 12’ diameter pool, but the incoming water flows over the spillway, that’s a lake?

xattt 4y ago
Yes! Lake Tamblyn at Lakehead University is one such small-diameter artificial “lake”. Of course, to confuse matters, a lake becomes a pond if damming was done by beavers. (1) https://goo.gl/maps/pwescdqRHeEAgrr37 https://goo.gl/maps/pwescdqRHeEAgrr37
brasic 4y ago
Definitely. See Lady Bird Lake or Lake Travis in Austin: basically just parts of the Colorado River.
- thaumasiotes 4y ago
  Lake Travis might be better characterized as a river, but if we call it a lake that still has nothing to do with the objection in your parent comment. Lake Travis's surface area is 19,000 acres. A 12'-diameter pool cannot be called a "lake" because it is far, far too small to qualify. Inflow and outflow don't enter into it. Note that by the proposed definition, all rivers and all segments of any river are lakes; outflow is always equal to inflow for any persistent body of water. Personally, I'd be more comfortable choosing whether to call Lake Travis a "river" or a "lake" based on whether there's a current on the surface. If yes, it's a river. If not, why not call it a lake.

bipson 4y ago

As mentioned below, every standing water has (on average) the same amount of inflow as it has outflow, otherwise it wouldn't be there in the first place ("dry up", evaporate, etc.) In fact, I know an artificial pond (and I guess there are many) that has no obvious inflow, but if you look closely and feel the waters 1-2 m below the surface, you realize it has massive inflow from ground-water (there is a large river just nearby), and there is a swampy area at the opposite end, where the pond has considerable outflow - just not as obvious. Now we could modify this to say, there must be obvious inflow from a river, stream or similar... But then again, in areas where there are not many big lakes nearby, e.g. Lower Austria, there are several "lakes" (often artificial) which I always jokingly criticize ("You call that a lake?"). If you grew up near e.g. Lake Constance or let's say Lake Michigan, most "lakes" are ponds for you, even if they have inflow. So I think most people would agree that surface area is the main differentiator, but I would say it is highly subjective where you draw the line.

thaumasiotes 4y ago
Large bodies of water with inflow from groundwater were a major cultural feature in India: https://en.wikipedia.org/wiki/Stepwell https://en.wikipedia.org/wiki/Stepwell Major groundwater engineering projects were also used in early Mesopotamia to inhabit otherwise unlivably dry areas. You'd dig a series of wells between the site and a mountain, with a tunnel connecting the bottoms of the wells. Water collected in the wells and flowed down the tunnel to the village.
gs17 4y ago
> If you grew up near e.g. Lake Constance or let's say Lake Michigan, most "lakes" are ponds for you, even if they have inflow. Definitely, to me it's not really a lake if you can see the entire opposite shore.