Tropical Dynamic Accumulator Species

Hello there!

Ive been hard pressed to find information about potential dynamic accumulators endemic to the amazon, im curious if anyone has any thoughts or suspicions about good plants to use in this capacity to help build soil in the Ucuyali River Basin which is mainly pure sand.  Curious also what peoples thoughts are on assuming that any species of plant that contains a wide variety of minerals inherently, could be considered in this category and used to recycle nutrients?  Thanks!

Hello Susannah!

Unfortuantely I am not a good source of information for  your question, given that I have been never been to the Amazonas before. What comes to mind is cassava (they can extract Phosphor from the soil that is usually not available for plants) and bamboo (silicate). But well, that are rather generic examples.

A bit off-topic: You said you want to build soil. For my understanding, you can't build soil in the tropics (except with biochar --> terra preta). The high temperatures lead to fast decay, and the heavy rains lead to extreme leaching. The first time I tried to do compost in the tropics, I was left with a thin layer of organic stuff that didnt decompose (because it was too dry outside) and apart from that: there was really nothing left. Since then I learned to add soil and biochar to the compost (and turn it frequently).

You mentioned that there is mostly sand: - well, that is just another word for black hole, which sucks everything, nutrients, water, you name it. On the bright side, you will never understand these people talking about the problems associated with waterlogging

Rather than building soil, you can build soil life: beneficial bacteria and fungi, that help provide nutrients occurring in the soil that are normally not water-soluble and therefore not available for plants. I think that is what the rain forest is actually doing.

Susannah, welcome to the forum!

I would look at what is already growing where you are at.

One of Fukuoka's main methods of improving and maintaining soil fertility without inputs was to plant a mix of deep rooted species that accumulate large amounts of minerals effectively. We call these "dynamic accumulators", and there are quite a few of them, each of which accumulates different minerals to different degrees

https://permies.com/t/19436/List-Dynamic-Accumulators

Thomas Schendel and Anne Miller...Thank you for your insight.  Yes, I am considering both of those plants as well as the potential for inoculated biochar and possibly cultivating certain water plants that can both clean the non potable reservoirs and add nutrients otherwise more difficult to obtain.  I have a long list of plants to consider for different applications,  plantain grows, there are a few species of native nettles, it seems like coca could have great potential as a DA since it contains a ton of different minerals, although not native to the jungle it will grow, also other medicinal type plants which often carry at least one important mineral if not a variety.  There are tons of leguminous trees and a bean type vine I see growing  prolifically.   With so much fish being consumed in the area it should also be easy to produce a fish emulsion.  I am having lots of different thoughts about potential plants and am curious if others are working to this capacity in the area, or in a location with similar challenges.  

Yes, making and holding soil isn't really how the jungle environment works and trying to improve a sandy structure does literally seem to be a bit of a drain.  However, observing the natural, undisturbed jungle, I do see a pretty decent layer, maybe a 18" of organic material that is surely feeding and supporting the local flora, the sand is also very fine so it doesn't drain as quickly as one might think.  My feeling is to recreate a jungle environment but with the desired plants for the organization I am working with, ie. perennial vegetables, fruits and medicine.  It seems like adding tons of biomass of specific species, ie. plants that accumulate a broader spectrum of nutrients and potentially hold moisture ie. bananas, annual root crops that can die in the soil and add organic matter in the lower strata, cover crops etc, that one could possibly slowly change the substrata to be able to hold more nutrients.  Ultimately, the leaching that occurs most likely leaves some nutrient rich residue in the deeper strata as the topography is pretty flat and the bed rock quite deep.  My feeling is that it may almost be a positive attribute to store nutrients deeply rather than only feeding shallow roots as part of the issue is the trees not sending their roots as deeply, due to so much of the nutrient being a the surface, thus encouraging a lot of risk for felling.  The jungle also exists in such a dense configuration that every species is vying and competing for resources that decompose quickly and potentially leach even faster.  By creating more deliberate tiered guilds in island beds I am hoping to reduce this competition and that it will encourage more stable canopy trees that are fed by the lower tiers of smaller trees, shrubs, coppice trees, leafy perennials, herbs, leguminous ground covers, etc.    Trying to think like a tree here;)...

I appreciate your input as I continue my exploration!

Susannah Gelb wrote: it seems like coca could have great potential as a DA since it contains a ton of different minerals, although not native to the jungle it will grow,

The thing is that is not how Dynamic Accumulators work.

It is not what is in the plant , instead it is how the plant draws minerals from the soil.

to indicate plants that gather certain minerals or nutrients from the soil and store them in a more bioavailable form and in high concentration in their tissues, then used as fertilizer or just to improve the mulch.

https://en.wikipedia.org/wiki/Dynamic_accumulator

Yes, I understand that the minerals must be in the soil for them to uptake. However, some plants have more aptitude to accumulating different minerals so one can create a nutrient loop by feeding the soil with specific plants that have one or two, allowing the DA to pick up all and then using that plants leaves etc, to recycle more into the soil for other plants to thrive.  Since Coca can store many different nutrients it seems a good "pantry" plant to pick up from other composting plants, teas, fish emulsions, etc.  It also being a small shrub, will have deeper roots to uptake from deeper strata which otherwise may be lost from leaching.  

I think Anne Miller makes a very good point: The dynamic accumulator must be able to mine certain minerals/nutrients that are not easily available for other plants. Otherwise banans could be also considered dynamic accumulators, since they certainly take up a lot of nutrients - but the point is that these nutrients need to be bioavailable.

Since Coca can store many different nutrients it seems a good "pantry" plant to pick up from other composting plants, teas, fish emulsions, etc.

All this fertilizing methods you mentioned have one thing in common - their nutrients are highly bioavailable. It seems to be me that you are looking for a high recycling rate of organic mattter. In this case, instead of concentrationg on dynamic accumulators, I would recommend planting in different layers (strata) to increase biomass density per area. Combinations of banana and Chaya or egg plant and mung bean would be simple examples of planting in different strata.