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Re:Why are Pakistan’s floods so extreme this year? by CommanderData on Friday September 02, 2022 @11:42AM (#32692091)
I read someone else suggest Permaculture as a way of mitigating some of the affects of monsoons in these types of areas.

Does anyone have any evidences of such a thing working?

Re:Why are Pakistan’s floods so extreme this year? by mountaintimefrm on Friday September 02, 2022 @04:59PM (#32695651)
Probably the best documented example of it working is in the Loess Plateau in China. John D Liu has a couple documentaries on it, here is one: https://youtu.be/IDgDWbQtlKI

A good example of a similar project in India, as covered by Andrew Millison: https://youtu.be/jDMnbeW3F8A

Sepp Holzer did a similar project in Portugal: https://www.youtube.com/watch?v=OUryneCjxV4 ...I believe he also did some pretty large projects in the middle east, but I can't find any vids on them at the moment.

Geoff Lawton has done a ton of projects like this, but maybe not at the landscape wide scales like the projects above.

Probably the best book on the basic principles of how to do it - Rainwater Harvesting for Drylands and Beyond by Brad Lancaster. Also the book Water For Every Farm by P.A. Yeomans is pretty good as well, but not as accessible of a read.

TLDR - To keep desert monsoons from flooding areas downstream, dig a landscape wide network of swales and basins to catch, soak and sink the water into the soil. Properly dug, such earthworks recharge aquifers while stopping flooding and erosion.

Re:Why are Pakistan’s floods so extreme this year? by pvaldes on Friday September 02, 2022 @01:32PM (#32693468)
I can't see how it could help having tons of plastic also floating in the river and expensive gravel filling the river bottom. The best way would still be to work with the monsoon, not against it.

But maybe I'm not understanding the solution. Can you explain more the idea?

Re:Why are Pakistan’s floods so extreme this year? by sophacles on Friday September 02, 2022 @04:33PM (#32695423)
Permaculture has nothing to do with tons of plastic nor gravel filling the river bottom.

Permaculture is: the development of agricultural ecosystems intended to be sustainable and self-sufficient.

I presume GP meant that by having more persistent vegetation in the area, that vegitation would do vegetation things and help with flood control.

Re:Why are Pakistan’s floods so extreme this year? by pvaldes on Saturday September 03, 2022 @06:01AM (#32700344)
I see, I was thinking in hydroponics, both terms are often associated.

I'm sceptical when I see agriculture wrapped in hype terms. I think that engineering will play a bigger role here. Forest restauration and dams that would retain soil and water and absorb part of the hit will help.

Just to speculate about possible partial solutions, I think that in plain areas subject to frequent flooding they could erect small hills and build the houses over those to defend homes. As floods will increase in the future, the sooner they start, the better.

They could also to dig a system of storm ponds. So will have many soil to build the hills. Moving soil can be done in the same step. The base of the hills should be heavily reforested to retain the soil in place. As a bonus you increase the forested area and help nature to flourish.

The other solution would be to dig concrete canals for as water highways but that would remove the main reason why people lives there: Very rich soil for agriculture plus water. You don't want all of this water lost in the sea

Storm ponds would play a benefit role to store water for the dry season also.

Re:Why are Pakistan’s floods so extreme this year? by peteradio on Friday September 02, 2022 @11:46AM (#32692161)
Sounds ridiculous on its face, and that is as a practitioner of permaculture. I couldn't really get my head around how it could possibly make even a slight dent against the massive flooding witnessed here.
Re:Why are Pakistan’s floods so extreme this year? by Panino on Friday September 02, 2022 @12:15PM (#32692527)
When Gabe Brown switched from conventional agriculture to regenerative agriculture, he increased water infiltration in his soil from 0.5 inches (1.25cm) per hour to 30 inches (75cm) per hour. So imagine if he and all his neighbors had the same beautiful soil -- flooding just couldn't happen.

I haven't seen a list of such measurements from permaculture, but I know it can be used to regreen deserts (as shown in Jordan, Saudi Arabia, Arizona and elsewhere). And I assume permaculture vastly increases water infiltration. Geoff Lawton has videos showing Zaytuna Farm happily surviving drought and flood alike.

If farmers switched from conventional agriculture to some combination of regenerative agriculture and permaculture, most flooding would be prevented. Their own fields would easily infiltrate rain, eliminating runoff that builds up into flooding.

The article mentions that in addition to Pakistan getting double the normal amount of rain, increased glacier melt is filling the Indus river. I assume that in the theoretical situation of all farmers in Pakistan practicing regenerative ag or permaculture, that land on the Indus would flood. But not 1/3 of the country as we're seeing now, and the flooded areas would recover faster.

Re:Why are Pakistan’s floods so extreme this year? by hedora on Friday September 02, 2022 @04:58PM (#32695648)
Water infiltration is measured by digging a small hole, filling it with water, and seeing how fast it drains. There's no way that regenerative agriculture has changed soil composition multiple feet down, which is what would be needed for the soil to absorb multiple feet of water.

I went to check the above sentence, and the first hit was this detailed article from Washington State, which analyses Brown's claims in detail, and explains why the scientific community is skeptical of them:

https://csanr.wsu.edu/regen-ag-solid-principles-extraordinar...

Anyway, even if, as Gabe Brown claims, regenerative agriculture is an order of magnitude more effective than expected, and you applied it to 100% of the land in Pakistan, it would still only reduce flooding by less than a foot.

Re:Why are Pakistan’s floods so extreme this year? by mountaintimefrm on Friday September 02, 2022 @05:40PM (#32696030)
> Water infiltration is measured by digging a small hole, filling it with water, and seeing how fast it drains.

Informally yes, but the scientific way is to use a ring infiltrometer: https://www.fao.org/3/s8684e/s8684e0a.htm -- Basically instead of digging a hole, you pound a pipe into the ground and then fill the pipe with water.

As for agricultural practices being able to change soil composition multiple feet down, trees and tap-rooted plants are very effective at placing large volumes of organic matter at depth. One example, Lacy Phacelia (Phacelia tanacetifolia) is an annual plant that produces a dense fibrous root system that reaches a depth of 4 feet; in the fall the Phacelia plants die, and their roots decompose at depth, creating pathways for water infiltration while also increasing soil organic matter at depth. The same goes with other trees and shrubs. The farmer from the "It ain't much but it's honest work" meme, Dave Brandt, has some really enjoyable presentations on youtube about improving soil composition at depth.

Re:Why are Pakistan’s floods so extreme this year? by worik on Friday September 02, 2022 @05:13PM (#32695775)
> . There's no way that regenerative agriculture has changed soil composition multiple feet down

How do you know that?

How deep do roots go? Do worms dig? Do you know?

I do not. But I am not making assumptions

Re:Why are Pakistan’s floods so extreme this year? by hedora on Sunday September 04, 2022 @11:10PM (#32720080)
Read the article I cited.
Re:Why are Pakistan’s floods so extreme this year? by peteradio on Friday September 02, 2022 @12:36PM (#32692798)
Any link to read about this 0.5 - 30 inch/hr conversion? Cultivated soil or already wetted soil will absorb much more readily than not, was this a carefully controlled experiment? Anyway it would take some serious modelling not handwavy yes or no as to whether permaculture/regenerative techniques (and a well defined definition of success of mitigation) could work. I absolutely admit that it could help on the margins, but would it have really have changed the image featured in this comment: https://news.ycombinator.com/item?id=32692060 ? Is the supposition that this water would find its way to some aquifer?
Re:Why are Pakistan’s floods so extreme this year? by Panino on Friday September 02, 2022 @12:44PM (#32692892)
> Any link to read about this 0.5 - 30 inch/hr conversion?

Read From Dirt to Soil by Gabe Brown. He also mentions the first inch (2.5cm) infiltrates in 9 seconds! So his soil drinks up more water in 9 seconds than nearby farms do in an entire hour.

> was this a carefully controlled experiment?

NRCS water infiltration tests.

https://www.nrcs.usda.gov

Re:Why are Pakistan’s floods so extreme this year? by carapace on Friday September 02, 2022 @04:55PM (#32695612)
Check out: Treating the Farm as an Ecosystem with Gabe Brown Part 1, The 5 Tenets of Soil Health https://www.youtube.com/watch?v=uUmIdq0D6-A

His neighbor's farm floods, his land soaks it up like a sponge.

Year-on-year his topsoil gets deeper.

Re:Why are Pakistan’s floods so extreme this year? by CapitalistCartr on Friday September 02, 2022 @01:27PM (#32693400)
Living in similar conditions in Florida, I know at about 4 inches per hour on a plain, you're screwed. It floods badly. And we have excellent drainage systems.
Re:Why are Pakistan’s floods so extreme this year? by joshuajill on Friday September 02, 2022 @01:06PM (#32693144)
Maybe even relatively simple but massive reforestation efforts could help mitigate climate change effects in the long run.
Re:Why are Pakistan’s floods so extreme this year? by worik on Friday September 02, 2022 @05:20PM (#32695835)
Forests are not very good carbon sinks except in the short run.

They have three problems when used as carbon sinks:

1) They tie up land for one, otherwise, non productive purpose (the wild species living in them do not mind that, must be said)

2) Once fully grown they reach a carbon balance. This can happen surprisingly quickly, a few decades.

2) Forests do not simply sit there like a rock. Eventually they will burn unless managed. Then they simply release all that stored carbon into the atmosphere.

Regenerative agriculture is a much better carbon sink. The process of storing the carbon increases the soil fertility so it is a win/win. Soils can get very deep so there is not a natural limit like for forests.

A draw back is measuring the carbon sunk. I do not know of anybody doing that (a market opportunity?). An important part of carbon farming is selling the "carbon credits" (a mad bad and sad idea, but it is a thing) to do that there must be an accepted measure of carbon sequestration, like there is for trees.

Re:Why are Pakistan’s floods so extreme this year? by joshuajill on Tuesday September 06, 2022 @04:20AM (#32734396)
Agree but don't forests do much more for weather events than being carbon sinks?

AFAIK they also create a more moderate micro climate, reducing soil temperature, retaining humidity and rain while keeping it in the soil, reducing the risk of draughts.

Of course regenerative agriculture is much better but the effort to implement it at a scale is incomparably greater, while it should not be shunned.

Also agroforestry will help with making agriculture possible in larger areas of land.

Re:Why are Pakistan’s floods so extreme this year? by Gravityloss on Saturday September 03, 2022 @08:00AM (#32700982)
At least over here, trees grow for centuries. Big trees survive forest fires as well.

Not a short term carbon sink only.

Re:Why are Pakistan’s floods so extreme this year? by mountaintimefrm on Friday September 02, 2022 @05:15PM (#32695795)
Gabe Brown's work is primarily on improving soil health, not on earthworks for flood prevention, aquifer recharge, etc. His gains in rainwater infiltration is a secondary effect of the steps he's taken to improve his soil.

In terms of projects whose primary aim is flood prevention / aquifer recharge, John D. Liu, Andrew Millison, and Geoff Lawton all have documented quite a few projects that have been very successful in addressing the problem.

Re:Why are Pakistan’s floods so extreme this year? by asah on Friday September 02, 2022 @12:38PM (#32692811)
naive q: does that still help if the aquifer gets saturated?
Re:Why are Pakistan’s floods so extreme this year? by nerdponx on Friday September 02, 2022 @12:40PM (#32692842)
Is an aquifer ever likely to get saturated? I have no expertise in this area, but in the US at least the concern is always over aquifers being depleted, not so fully saturated that they can't absorb more water. My understanding was that it takes very long time for water to actually get from ground level down into an aquifer.
Re:Why are Pakistan’s floods so extreme this year? by bombcar on Friday September 02, 2022 @01:21PM (#32693336)
At some point the ground cannot accept anymore water, no matter what.

Proof: oceans exist.

The key to the whole thing is if you can slow it down enough so that a sudden deluge over a day/week/month has time to slowly drain out.

Getting water into an aquifer takes time depending on how the soil is, but eventually the aquifer would rise to the surface and you'd have a marsh. Or it would rise higher and you'd have a lake.

Re:Why are Pakistan’s floods so extreme this year? by munificent on Friday September 02, 2022 @02:59PM (#32694545)
This depends entirely on where you live. Sure in the Southwest, there's a big problem with drought. But along the Gulf Coast, the water table is astonishingly close to the surface. When my family put in an in-ground pool in Louisiana, they had to start filling the concrete pool with water even before finishing it because if they left it empty, the surrounding water table would push it up out of the ground like a floating boat.
Re:Why are Pakistan’s floods so extreme this year? by alar44 on Friday September 02, 2022 @12:35PM (#32692776)
Yeah just imagine if a billion people completely changed their way of life.
Re:Why are Pakistan’s floods so extreme this year? by IX-103 on Friday September 02, 2022 @01:10PM (#32693195)
I'm not sure if you're being sarcastic or not. Climate change is going to require changes of at least that scale, whether we reduce emissions or not.
Re:Why are Pakistan’s floods so extreme this year? by zaroth on Friday September 02, 2022 @02:05PM (#32693889)
Luckily for humanity that won’t actually be necessary.

In the next 20-30 years I suspect we’ll just moderate total solar irradiance as-needed by injecting moon dust into L1.

The only issue is if there are powerful countries that are actually benefiting from the warming and don’t want to cool it down bit.

Re:Why are Pakistan’s floods so extreme this year? by blooalien on Friday September 02, 2022 @08:05PM (#32697149)
Luckily for humanity that won’t actually be necessary because in the next 20-30 years we're likely to revert to savagery and barbarism, and "civilized" behaviors won't matter anymore (assuming one of our "leaders" doesn't do the epic stupid and get us all "nuked" out of existence).
Re:Why are Pakistan’s floods so extreme this year? by CommanderData on Saturday September 03, 2022 @03:56AM (#32699733)
I think that's pretty easy if government incentives are in place.
Re:Why are Pakistan’s floods so extreme this year? by lijogdfljk on Friday September 02, 2022 @02:13PM (#32694007)
Imagine if they don't.
Re:Why are Pakistan’s floods so extreme this year? by 11235813213455 on Friday September 02, 2022 @12:32PM (#32692732)
permacultures are some super carbon sinks, anti-erosion systems, absorption systems and organic food producers, each one is just a grain of sand (https://en.wikipedia.org/wiki/Sorites_paradox), but many grains do the job along with lifestyle changes
Re:Why are Pakistan’s floods so extreme this year? by loonster on Friday September 02, 2022 @12:05PM (#32692426)
The more water that is retained on the property, the less that is available for entering streams.
Re:Why are Pakistan’s floods so extreme this year? by bergenty on Friday September 02, 2022 @12:07PM (#32692447)
Lots of small water retaining walls and pits makes it so it doesn’t run off and accumulate in some low central area.