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Author Topic: Iron pan soil ,tropical rainforest soil  (Read 746 times)

SeaWalnut

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Iron pan soil ,tropical rainforest soil
« on: February 10, 2020, 08:50:06 PM »
I found an iron pan ( a type of soil rich in iron) on the river bed near home and i think i can say now that i have real tropical rainforest soil to grow my plants.
Its rich in iron and manganese ,should be verry low ph and off course the color its deep red like the soil of the rainforest.
Its basically iron ore with low ph and low nutrients.

Why i found this tropical soil here its because this iron pan formed where a spring used to flow and that continuous flow of water weathered the soil soo much until it became like laterite.
Just like the rains washed the soil in the tropics until they became red.
Will be adding pictures tomorrow and explain what the iron pan is and how to recognise different minerals in it.

Might not seem much that i found this red soil but i live in a place with alkaline soil and you cant buy such soil like regular  potting soil.

lebmung

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Re: Iron pan soil ,tropical rainforest soil
« Reply #1 on: February 11, 2020, 07:25:56 AM »
I found an iron pan ( a type of soil rich in iron) on the river bed near home and i think i can say now that i have real tropical rainforest soil to grow my plants.
Its rich in iron and manganese ,should be verry low ph and off course the color its deep red like the soil of the rainforest.
Its basically iron ore with low ph and low nutrients.

Why i found this tropical soil here its because this iron pan formed where a spring used to flow and that continuous flow of water weathered the soil soo much until it became like laterite.
Just like the rains washed the soil in the tropics until they became red.
Will be adding pictures tomorrow and explain what the iron pan is and how to recognise different minerals in it.

Might not seem much that i found this red soil but i live in a place with alkaline soil and you cant buy such soil like regular  potting soil.

At tropics soil it's not always red, full of iron and sandy. It depends on location. In a true tropical jungle it has layers of decomposing material.  Some plants live well others don't. I would not use that.

SeaWalnut

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Re: Iron pan soil ,tropical rainforest soil
« Reply #2 on: February 11, 2020, 08:53:27 AM »
Tropical rainforest soil its red because it rains verry much .

This is where the stream used to flow.Because of the long term constant wash of water,the soil became red ,similarly to the soil in the rainforest.


This is the famous( or infamous) iron pan.It is a layer with more iron and manganese in it than the rest of the red soil and its hard almost like concrete.


The red coloration its from the iron and it looks like rust because thats what it is.
But its not just rust.


Tiny bits of shiny black among the most reddish portions are manganese but not all black its manganese only the verry small jet black concentrated bits.


On top of the iron pan and throughout it there are bacteria specialised in iron.These bacterias make the iron available for plants and they are in the dark grey / black portions.


I think that the iron pan has all the qualities and minerals of the tropical soil concentrated in it .It has same minerals as the red soil but much more dense and can be ,,diluted,, with regular soil,manure ,etc.
I took somme home.
« Last Edit: February 11, 2020, 09:18:01 AM by SeaWalnut »

SeaWalnut

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Re: Iron pan soil ,tropical rainforest soil
« Reply #3 on: February 11, 2020, 09:26:18 AM »
This is where somme small streams used to flow through the cracks in the pure clay soil.Iron oxide deposited right where the water used to flow.


NOTE: il use this soil as an experiment and i dont advise nobody to do the same as i dont know the results iet.
Its a verry poore and acid soil to begin with but its like the base of the rainforest soil.

Also,the colors are much more vibrant red in reality than in the pictures.
« Last Edit: February 11, 2020, 09:37:28 AM by SeaWalnut »

lebmung

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Re: Iron pan soil ,tropical rainforest soil
« Reply #4 on: February 11, 2020, 04:53:56 PM »
I tell you what I have seen in real life. The red soil is not the best.
Like for instance tomatoes grown at tropics in the red soil are very bad. They don't get red and tasty like in the black rich humus soil. Some native trees yes they do fine.
it all depends what you want to grow each plant has different needs.
It's very wrong to say that most tropicals like acidic soil. They don't. They like neutral, slightly acidic soil which is another story.

SeaWalnut

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Re: Iron pan soil ,tropical rainforest soil
« Reply #5 on: February 13, 2020, 08:48:52 PM »
The temples of Angkor Wat from Cambodgia jungles are build from iron pan stone( laterite).
The iron pan its considered both,a soil and a stone.
All the Amazonian forest its grown on this red soil.

SeaWalnut

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Re: Iron pan soil ,tropical rainforest soil
« Reply #6 on: February 15, 2020, 04:38:47 PM »
After i measured the ph of the iron pan i fount its 8 😂 and not acidic as expected,due to the verry sodic soil it was located.
But the good news its that altough the ph its 8,it has verry little buffer in it and can be corected easily and with little acid.
The ammount of buffer its soo low ,similar to the buffer in the rain water .
For the minerals like those from rainforest soil and for the iron eating bacyeria i think its a good soil to mix with manure for rainforest plants.

pineislander

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Re: Iron pan soil ,tropical rainforest soil
« Reply #7 on: February 15, 2020, 07:37:27 PM »
You can't really typify a "tropical" soil. They can range from volcanic to calcareous sedimentary, and peats to highly weathered acidic clays. For those of us in Florida here is a classification of soil types based on how they developed from parent rock moisture and climate.
https://edis.ifas.ufl.edu/ss655

SeaWalnut

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Re: Iron pan soil ,tropical rainforest soil
« Reply #8 on: February 15, 2020, 08:16:47 PM »
You can't really typify a "tropical" soil. They can range from volcanic to calcareous sedimentary, and peats to highly weathered acidic clays. For those of us in Florida here is a classification of soil types based on how they developed from parent rock moisture and climate.
https://edis.ifas.ufl.edu/ss655
Its tropical rainforest soil.
On calcareous soil there wont be rainforest because the intense rain would disolve and wash the calcium carbonate.
Like it did in Mexico forming the cenotes sinkholes.
Off corse this is not just ,,tropical,, but ,,tropical rainforest,, most likely to be there soil.Variations exist.
In american clasification this red soil is an oxisoil/ ultisoil .

pineislander

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Re: Iron pan soil ,tropical rainforest soil
« Reply #9 on: February 15, 2020, 08:53:01 PM »
Plenty of tropical forests exist in every single soil classification. I have personally seen some of these, including calcareous soils from limestone. The cockpit country of Jamaica is an example. You can go there and see for yourself if you don't believe me. There are plenty more.
https://www.youtube.com/watch?v=9hccMWioloQ

SeaWalnut

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Re: Iron pan soil ,tropical rainforest soil
« Reply #10 on: February 15, 2020, 09:51:54 PM »
Plenty of tropical forests exist in every single soil classification. I have personally seen some of these, including calcareous soils from limestone. The cockpit country of Jamaica is an example. You can go there and see for yourself if you don't believe me. There are plenty more.
https://www.youtube.com/watch?v=9hccMWioloQ
Verry interesting biome i didnt know before.
It is a rare exception thogh and thats why there are soo manny endemic animals living there .
Its a relatively young rainforest and barely can be called a rainforest as there is drought there and snails adapted to resist drought as well as the frogs.
A real rainforest creates its own rain wich washes away all the calcium and turns the soil red.
The weathered red soil of the rainforest its verry bad,low in nutrients and basically a desert like Sahara or australian outback where only the rain caused by the rainforest keeps it alive.
Once the rainforest its cut there is no rain and desertification occurs like in Madagascar and  otther such places.

pineislander

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Re: Iron pan soil ,tropical rainforest soil
« Reply #11 on: February 15, 2020, 10:44:11 PM »
Karst landscapes are worldwide in the tropics. Typicaly full of caves, springs, cockpits and towers/highly eroded landforms. Thailand is famous for it. Rainforests can be seasonally dry.

lebmung

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Re: Iron pan soil ,tropical rainforest soil
« Reply #12 on: February 16, 2020, 07:11:20 AM »
I visited that place many times thise trees in the temples are outstanding. That area is very dry during winter and hot during rainy season.  There is variation of soil fhere also. In mekong area the soil is rich and darker.

The temples of Angkor Wat from Cambodgia jungles are build from iron pan stone( laterite).
The iron pan its considered both,a soil and a stone.
All the Amazonian forest its grown on this red soil.


NateTheGreat

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Re: Iron pan soil ,tropical rainforest soil
« Reply #13 on: February 16, 2020, 11:10:22 AM »
The soil in the Amazon is also infertile, hence why the Terra preta was created. The Amazon relies on Sahara dust.

Guanabanus

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Re: Iron pan soil ,tropical rainforest soil
« Reply #14 on: February 16, 2020, 12:37:47 PM »
The Amazon region is not an ecosystem--- it is a patchwork of many different ecosystems, including wide variations in soils.

The rivers coming out of these regions are different colors.  The assemblages of flora and fauna are distinct.
Har

SeaWalnut

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Re: Iron pan soil ,tropical rainforest soil
« Reply #15 on: February 16, 2020, 03:29:17 PM »
Oxisol or red leached soil map of the Amazon rainforest.
Also the yellow brown in the map are red soils,ultisoils like those in Australia.
I agree there is a lot of variation in the soil of the rainforests but the main soil in rainforest in 99% of the cases is this red soil rich in Iron and manganese.


This soil is good for cocoa plantations and otther such rainforest fruits.
« Last Edit: February 16, 2020, 03:31:51 PM by SeaWalnut »

Guanabanus

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Re: Iron pan soil ,tropical rainforest soil
« Reply #16 on: February 16, 2020, 09:33:01 PM »
Nice map!

I grew up in that yellow spot to the east of the confluence of the Negro River with the Solimoes / Amazon.
Flat areas were usually 1-3 feet of sand, with sandy pebbly yellowish clay below that.  O.K. for some types of farming, and for fruit trees.

Wide areas to either side of the Negro are extremely sandy, with pH in the 3.5-4.5 range.  Terrible for most types of agriculture.

Wide areas to either side of the Amazon River are rich floodplain mud--- highly fertile when not flooded, good for 3-6 month crops.
Har

SeaWalnut

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Re: Iron pan soil ,tropical rainforest soil
« Reply #17 on: February 17, 2020, 06:14:25 AM »
Nice map!

I grew up in that yellow spot to the east of the confluence of the Negro River with the Solimoes / Amazon.
Flat areas were usually 1-3 feet of sand, with sandy pebbly yellowish clay below that.  O.K. for some types of farming, and for fruit trees.

Wide areas to either side of the Negro are extremely sandy, with pH in the 3.5-4.5 range.  Terrible for most types of agriculture.

Wide areas to either side of the Amazon River are rich floodplain mud--- highly fertile when not flooded, good for 3-6 month crops.
Nice place to spend the childhood.
The water of Rio Negro its black because of humic acid.
I use pyroligneous acid( humic acid) as fertiliser and little  ammount of this acid turns the water black if it has somme hardness in it.
The soil on the Rio Negro basin its a red soil mainly.
Its is a terible poore soil wich makes the rainforest more amazing as an ecosystem.



Rio Negro and Amazon confluence + a river dolphin.
« Last Edit: February 17, 2020, 06:17:49 AM by SeaWalnut »

pineislander

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Re: Iron pan soil ,tropical rainforest soil
« Reply #18 on: February 17, 2020, 07:15:01 AM »
I agree there is a lot of variation in the soil of the rainforests but the main soil in rainforest in 99% of the cases is this red soil rich in Iron and manganese.
This map shows the global prevalence of Oxisols.



SeaWalnut

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Re: Iron pan soil ,tropical rainforest soil
« Reply #19 on: February 17, 2020, 05:41:38 PM »
I agree there is a lot of variation in the soil of the rainforests but the main soil in rainforest in 99% of the cases is this red soil rich in Iron and manganese.
This map shows the global prevalence of Oxisols.


Oxisol its in american terms but the corect map is this one with Laterite soil.

pineislander

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Re: Iron pan soil ,tropical rainforest soil
« Reply #20 on: February 18, 2020, 08:04:33 AM »
Seawalnut your two maps don't align, the former shows the modern soil classifications the latter obsolete. I had a discussion of this with my sister who has a PhD in geology. She tells me that the problem with characterizing all tropical soils the way you are trying to do is space and time. Soils do form due to climate but within space and time climate and soil formation processes are not constant. For instance, over time continental drift changes climate. An area now with a rainy season may have once been a desert, a monsoon or a seasonal forest. Uplift of sedimentary areas like in Jamaica's cockpit country leaves formerly submerged land high into mountains. Volcanism and even impact events can change the soil type in minutes or days. For these reasons, the colorful map of soil types show as accuately as possible the differences. There are also suborders detailing differences within the orders depending on current moisture and temperature.

SeaWalnut

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Re: Iron pan soil ,tropical rainforest soil
« Reply #21 on: February 18, 2020, 02:29:49 PM »
The last map i posted was a generalisation of weathered ferrosoils.Theres lot of variation within those red soil area.
I know well the phenomenon wich caused Cockpit Country because Romania was also the bottom of a sea that got lifted and here you can find seashell fossils on top of the mountains( verry common).
Even the mud volcanoes in my blog about Nitraria ,they used to be on the bottom of the sea .They are like those in California that just got out of the sea,but colder.
We have a lot of Karstic formations here ,a lot of caves ,a lot of limestone,marble , and salt ( i have a saltwater river passing near me and i am 400 km away from the sea).

Such aged red soil its precious to me as it is the tropical rainforest soil and its verry different than my local soil.
If i want to grow rainforest species and somme rare ,unknown in cultivation,il try to mimic their native soil .
Somme tropicals like seashore mangosteen and Durian can grow in verry acidic and also verry alkaline soils but not all the tropical plants are that well adapted to such variations.
« Last Edit: February 18, 2020, 02:33:58 PM by SeaWalnut »

Guanabanus

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Re: Iron pan soil ,tropical rainforest soil
« Reply #22 on: February 18, 2020, 08:20:48 PM »
This last map shows the Yucatan Peninsula the same color as the rest of the tropics.  Why?  Almost the entire peninsula is calcareous.
Har

SeaWalnut

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Re: Iron pan soil ,tropical rainforest soil
« Reply #23 on: February 18, 2020, 09:10:41 PM »
This last map shows the Yucatan Peninsula the same color as the rest of the tropics.  Why?  Almost the entire peninsula is calcareous.
Its similar with Pineislander example with Cockpit country.
There are bauxite mines in Yucatan peninsula as well as in the Cockpit Country ( wich i didnt mentioned by now not to look like im contradicting Pineislander).
There are 2 types of bauxite ores,lateritic bauxite and in Yucatan and Jamaica ,karstic bauxite that occurs on limestone.
As limestone gets weathered and disolved ,over time the soil turns to bauxite or laterite.Mainly iron and aluminium remains wich gives these soils the red color.

The last map ive posted its a generalisation and its not acurate( for instance i would make whole Australia red and even somme parts of N America and Europe where in the past there used to be rainforests.

Main idea is that upon weathering ( washing of the rain) the soil becomes red and looses somme elements like calcium and becomes concentrated in iron and aluminum( aluminum= clay soil).

My rich  black soil with limestone its verry different from the rainforest soil because its not that weathered( washed soo much by rain).

Here is a nice link with the red soil of Yucatan peninsula.Nice pictures but the guy thinks eroneously that the iron pan layer was formed by a volcanic eruption.
Probably because he is not familiar with iron pans.https://www.backyardnature.net/yucatan/soil.htm
« Last Edit: February 18, 2020, 09:20:26 PM by SeaWalnut »

echinopora

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Re: Iron pan soil ,tropical rainforest soil
« Reply #24 on: February 18, 2020, 09:32:54 PM »
Being in zone 6, are you growing in pots? I'm on deep weathered red soils, but i wouldn't consider putting it in a pot, its a recipe for disaster.



 

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