SoylentNews is people
SoylentNews
Local water availability is permanently reduced after planting forests:
River flow is reduced in areas where forests have been planted and does not recover over time, a new study has shown. Rivers in some regions can completely disappear within a decade. This highlights the need to consider the impact on regional water availability, as well as the wider climate benefit, of tree-planting plans.
"Reforestation is an important part of tackling climate change, but we need to carefully consider the best places for it. In some places, changes to water availability will completely change the local cost-benefits of tree-planting programmes," said Laura Bentley, a plant scientist in the University of Cambridge Conservation Research Institute, and first author of the report.
Planting large areas of trees has been suggested as one of the best ways of reducing atmospheric carbon dioxide levels, since trees absorb and store this greenhouse gas as they grow. While it has long been known that planting trees reduces the amount of water flowing into nearby rivers, there has previously been no understanding of how this effect changes as forests age.
The study looked at 43 sites across the world where forests have been established, and used river flow as a measure of water availability in the region. It found that within five years of planting trees, river flow had reduced by an average of 25%. By 25 years, rivers had gone down by an average of 40% and in a few cases had dried up entirely. The biggest percentage reductions in water availability were in regions in Australia and South Africa.
Partial river flow recovery with forest age is rare in the decades following establishment (open, DOI: 10.1111/gcb.14954) (DX)
(Score: 5, Insightful) by corey on Friday January 31 2020, @02:13AM (4 children)
Is not stopping planting trees. More, careful selection of where to plant forests along rivers needed for human consumption.
This study is quite narrow and some in society will argue for less trees. Same as those living in the bush here in Australia due to bushfire risk. But less trees is not the only answer.
I'd be interested to know about research on the effect of forests in spawning rainfall (and microclimates). The Amazon generates it's own rainfall which supports it as a rainforest. And our water catchments in Australia's major cities are basically forests with dams.
(Score: 5, Informative) by Booga1 on Friday January 31 2020, @03:06AM (3 children)
You're absolutely right on several points. Benefits go far beyond simple water table levels. The question becomes: what is the largest benefit in the long term?
Check out this scenario(emphasis mine): A Brazilian couple replanted 1,502-acre forest in 20 years and also gave a home to 500+ endangered plant & animal species. [stillunfold.com]
(Score: 2) by corey on Friday January 31 2020, @10:30PM
Thanks for posting that, I didn't know about them. Really interesting.
(Score: 0) by Anonymous Coward on Friday January 31 2020, @11:07PM (1 child)
"After Salgado’s forest was created, it resulted in even more rainfall in the area."
So wait, is it saying that planting trees results in more rainfall? Seems far fetched no?
(Score: 2) by Booga1 on Saturday February 01 2020, @12:34AM
Not as far fetched as it might seem at first. Remember, trees add turbulence to wind, forcing air to slow down over the forest. This directly contributes to increased rainfall.
Trees also slow down the runoff of water by adding debris to the forest floor that slows down runoff and keeps more water locally instead of feeding rivers. At the same time, trees recycle that water back out of the ground and into the air. See Joe's post [soylentnews.org] for a bit of a rundown on that in Florida.
That rain water isn't necessarily "new" water. In part, it's just recycled water being dropped back over the forest it came from instead of being swept out to a different area via river, Whether that's the ocean, a city, or a forest further away just depends on the location. The net result is that forests can influence their own weather, rain included.
(Score: 5, Insightful) by Runaway1956 on Friday January 31 2020, @02:20AM (1 child)
(Pre)historically, trees grew everywhere. They tended to do several things, including prevention of soil erosion. Rivers, allowed to run freely, carve deeply into the land, carrying away soil and nutrients. Trees don't exactly reverse that trend, but they slow or stop it.
Trees drink a lot of water. That is, they take it up from the soil around them, and the water evaporates into the air. That's always been true.
So, we've deforested all of the cities, and much of the arable land, and even a lot of not-so-arable land close to the rivers. Putting some trees back, will return things closer to their natural state? Who'da thunk it?
Plant the trees, you bunch of goof balls. They help to control FLOODING!! Flooding is a bad thing, remember? Derp-a-derp. Finding excuses to not do the right thing has always been a pastime of do-nothing fools.
(Score: 4, Informative) by JoeMerchant on Friday January 31 2020, @03:54AM
One of the features of natural forests is ... well, I can't remember the word, but basically the organic "waste" on the forest floor acts as a slow-release sponge, so water that falls as rain spends a lot more time near the surface and runs down into rivers both more slowly, and importantly, more consistently over longer periods of time.
In Florida, most of the "riparian zones" have been stripped, cleared, turned to agriculture or residential / recreational use. The swamps have been mostly drained, so now when it rains that rainwater heads to the rivers quickly, and runs out to the sea quickly. They call it a "pulse" ecosystem - short deep floods followed by long periods of low flow, where the pre-settlement pattern had deeper water in the rivers most of the time, for many reasons including modern clearing of waterways to make them navigable...
Not only have people drained the aquifer through direct usage, the changes in surface permeability and water retention mean the aquifer recharges more slowly than in the past. Modern planning calls for retention ponds (gator pits), which is a step back in the right direction, but it's not at all the same as having a pine forest with a natural bed of fallen needles over a foot thick above the mineral soil. And some navigable rivers have locks installed, which does indeed keep their water levels up, but a locked river is usually a less than wonderful ecological system as compared to its pre-settlement state.
All in all, bring back the trees - although you might choose them carefully, some trees like the imported tea tree or melaleuca respire ridiculous quantities of water into the air. Some genius thought they could dry the everglades by air-dropping melaleuca cuttings. The cuttings did sprout, and the exotic trees did indeed respire a lot of water into the air (as if Miami needed MORE humidity), but they were far from drying out the ground or making it in any way useful.
Also, if the managers of the forests can refrain from raking the organic matter off the ground to make a buck or two in the short term, the trees will grow faster and earn them more money per year in the long run, as well as being better behaved in the water cycle and somewhat more friendly to forest dwellers.
🌻🌻 [google.com]
(Score: 3, Touché) by Captival on Friday January 31 2020, @02:55AM (13 children)
Breaking Front Page Headlines: Less Water Available Around Water-Consumers
(Score: 3, Insightful) by krishnoid on Friday January 31 2020, @03:26AM
Well, that's one way to take the piss.
(Score: 3, Interesting) by JoeMerchant on Friday January 31 2020, @03:35AM (11 children)
People who grow trees have pretty well mastered this one.
A common sight in Georgia is a lone pecan tree that gets surrounded by a pine planting, the pines suck so much water out of the soil that the pecan struggles to survive and stops producing completely, then the pines overtop it and shade it to death.
🌻🌻 [google.com]
(Score: 0) by Anonymous Coward on Friday January 31 2020, @05:13AM
The weak should fear the strong.
(Score: 2) by Booga1 on Friday January 31 2020, @06:16AM (8 children)
So, what you're saying is that pine trees use their needles to murder other trees?
(Score: 2) by JoeMerchant on Friday January 31 2020, @03:16PM
More the tap roots...
🌻🌻 [google.com]
(Score: 5, Informative) by Thexalon on Friday January 31 2020, @04:32PM (5 children)
They absolutely do: Their needles, when they fall, make the soil highly acidic, which murders many of the competitive species of trees. And that's why the floor of an evergreen forest has very different undergrowth from a deciduous forest that's specifically adapted to that environment and not really a threat to the pines.
One way that acid gets absorbed in the understory is in wood sorrel, a very tasty clover with heart-shaped leaves. Don't eat too much of it, but otherwise it's a nice mini-snack when you're out in the woods.
The only thing that stops a bad guy with a compiler is a good guy with a compiler.
(Score: 2) by Booga1 on Friday January 31 2020, @10:32PM
I was shooting for "funny," but I'll gladly take informative replies over imaginary internet points any day of the week.
(Score: 2) by dry on Saturday February 01 2020, @05:20AM (2 children)
Sorrel's are not a clover, more closer related to rhubarb, and contains oxalic acid, which in high enough doses is poisonous. It is good in moderation though.
(Score: 2) by Thexalon on Monday February 03 2020, @04:43PM (1 child)
Looking through the scientific classifications of the species in question, we're both wrong: You're right that sorrel isn't in the same Order as clovers even though it kinda looks like it ought to be. You, however, are incorrect in that it's actually more closely related to clover than rhubarb, because clover and sorrel share the common Clade of Rosids, while rhubarb doesn't.
The only thing that stops a bad guy with a compiler is a good guy with a compiler.
(Score: 2) by dry on Monday February 03 2020, @05:23PM
Ok, I see that you were actually talking about an Oxalis, https://en.wikipedia.org/wiki/Oxalis [wikipedia.org] rather then a sorrel, https://en.wikipedia.org/wiki/Sorrel [wikipedia.org] which I was talking about. I don't know of any wild oxalises (they are a horrible weed though) where I am whereas there are lots of wild sorrels. Both rhubarb and sorrel are in the family Polygonaceae, https://en.wikipedia.org/wiki/Polygonaceae [wikipedia.org]
This is the problem with using common names instead of the Latin species name, we end up talking about completely different plants thinking we're talking about the same ones.
(Score: 2) by hendrikboom on Monday February 03 2020, @12:02AM
Aren't acidic soils the kind that produces the best marijuana? Or have I remembered that wrong?
(Score: 0) by Anonymous Coward on Saturday February 01 2020, @06:32PM
Be aware of the needles they're tiny pricks.
(Score: 3, Interesting) by arulatas on Friday January 31 2020, @02:08PM
There is unrest in the forest
There is trouble with the trees
For the maples want more sunlight
And the oaks ignore their pleas
-Rush : Trees
----- 10 turns around
(Score: -1, Troll) by Anonymous Coward on Friday January 31 2020, @06:12AM (4 children)
Now we should be a little more thorough when making science, Laura Bentley. At least a few nails in the ground to measure soil humidity and a pinecone or a horsehair to measure air humidity. Perhabs another surprise will show itself if you bother to measure ground water levels.
(Score: 0) by Anonymous Coward on Friday January 31 2020, @07:27AM (3 children)
I've been told that California's oaks in particular hold a lot of water under ground. I actually got to see this first-hand when a rather small (and it turns out hollow and somewhat diseased) oak was cut from an unsuitable place between my house and another. Well into the month of June, and even July I observed water in the hollow of the stump. This doesn't sound like a big deal unless you realize that it's normal for us not to get any rain during those months, and we didn't. All that water was coming up from the root system. The poor thing did start suckering from the stump--a lush oak bush, but we'll just have to whack that back eventually because it's a bad spot for an oak. It may just die on its own--those burly bushes are susceptible to disease. I had one on another stump that died from powdery mildew after an unusual early Summer rain. There's some attrition on oak saplings I guess. The big oaks were unaffected.
(Score: -1, Offtopic) by Anonymous Coward on Friday January 31 2020, @02:19PM (1 child)
Yeah and besides that, I've heard the maples aren't too happy with the large oaks to begin with.
(Score: 0) by Anonymous Coward on Friday January 31 2020, @07:11PM
Aw geez moderators. Come on! What, was it too soon?
(Score: 0) by Anonymous Coward on Friday January 31 2020, @03:07PM
When I cut down an overgrown magnolia tree and pulled the stump out, there was a puddle of stinky water directly under the stump. The roots had found a leaky water meter 20 feet away.
(Score: 1, Offtopic) by aristarchus on Friday January 31 2020, @09:53AM
Reagan Cow Farts! Trump Ukrainian Interference! Newt Gingrinch intelligence!
See this book [abebooks.co.uk], for an entirely opposite hypothesis from the tree-hating fossil fuel crowd!
(Score: 0) by Anonymous Coward on Friday January 31 2020, @02:23PM (1 child)
I'll have to read the paper, but global water availability has been dropping over the last number of decades. I am curious whether their 25-year outlook takes that into consideration in their conclusions.
(Score: 2) by DannyB on Friday January 31 2020, @05:30PM
Could it be that an ever increasing population of humans could have an effect on water availability, or the health of the planet in general?
When trying to solve a problem don't ask who suffers from the problem, ask who profits from the problem.
(Score: 2) by jmichaelhudsondotnet on Friday January 31 2020, @03:49PM
Terrence Malick's new world, although a bad movie, has some of the best nature shots I have seen in any movie.
Imagine how it used to be, healthy, thriving, old growth forests that had been there for a long time.
Humans are a little like trees, we live in the same basic temperature range and need water, sun, fruit, etc.
The thing about a forest is, you get to know that there are probably not many hurricanes, fires, draughts, whatever that come through here.
Once the trees are gone, you do not get that assurance, anything could happen. The sand dunes could shift, the locusts could come, there could be a giant lazer clean the entire surface of the planet out of the blue.
Systems are so big that at some point our little human efforts to rebalance or rejigger things on the fly, like if we just plant new trees, if we just build more shade structures, levies, etc, fail becuase the instabilities bring new problems faster than anyone can solve them, and even the solutions have even more unpredictable side effects.
Or as Jared Diamond calls it, the 5th fear, that our own project management failures are the pedal to the metal of our own extinction, especially considering the paragons of money worship and short term thinking that are making the decisions that affect all of us at the moment.
Good luck planting trees when there are no glaciers refilling the groundwater, when all the groundwater is poisoned by fracking, when there is a dustbowl, firestorm, inland hurricane, locust attack and totalitarian government feeding all of the resources to gated communities while any of their servants and hordes of tree planting whack-a-molers with an iq over 100 is executed as soon as they are found out as a threat to the status quo.
These ecological problems are no threat to the master overlord class and so they will continue not to care as we starve and die ever more meaningless and dismal deaths, excluded from their fine clubs with all of the best people, and epstein.
thesesystemsarefailing.net
https://archive.is/ULMpO [archive.is] (add to the top part 'we get credibility and also as a bonus, safety from the disasters made inevitable by our degenerate way of life')