Reading more and more about agroforestry / reforestation / water availability I came across hydraulic redistribution (https://www.researchgate.net/publication/221752819_Water_release_through_plant_roots_New_insights_into_its_consequences_at_the_plant_and_ecosystem_level) performed by various types of vegetation. It sounds to me a very interesting option for agroforestry to use this kind of "bio-irrigation".
Since it is a purely biophysical process, I am wondering the following:
The amount of plants where hydraulic redistribution is proven is quite limited (based on literature I have compiled a list know around 200 species where hydraulic redistribution is proved), probably because the needed research takes quite some time and is labour intensive.
But it seems that the deeper the roots, combined with a heterogeneous soil, the higher the chance that hydraulic redistribution can take place.
In some species, hydraulic redistribution may not occur due to the prevention of water outflow, because of the fact that there is a deposition of suberin in endodermal and exodermal tissues.
Is there any research carried out on the thickness / existence of the suberin on roots, in order to distinguish which plants are likely to perform hydraulic redistribution, and which plants are unlikely to perform hydraulic redistribution?
Article Water release through plant roots: New insights into its con...
Hi..kindly have a look some info avialble here n elsewhere..Best..
http://file.scirp.org/Html/5-2601097_41027.htm
Hi Surender Singh. Thanks for your answer.
This article is written by Nobuhito Sekiya. I have been in touch with him on this topic, and he himself had not done the needed research to answer the question I have, his answer on my email was:
"Since the deposition of suberin in endodermal and exodermal tissues reduces water outflow, the quantity of water redistributed should depend on plant species. In some species, hydraulic redistribution may not occur due to the prevention of water outflow. Unfortunately, however, I have never investigated plant species from that perspectives. Thus, I am unable to answer your questions perfectly."
Suberin is a hydroxy fatty acid and phenolic acid polymers. So far, no reports have been done for the thickness of suberin. For the aerial plant organs it is cuticle function similar as the suberin. However, if we take cuticle as a reference, I would not recommend consider suberin thickness. Because no relationship between the thickness of cuticle and water relations of plant have been tested. Nevertheless, it is a good question, try it and confirm whether it has similar characters as cuticle.