So, Magnesium deficiency vs root: shoot ratio!

OK, just finished one of my Uni assignments this week due to be handed in on Friday and its got me thinking about a few things.  Magnesium deficiency in plants and trees causes a number of symptoms and also effects plant growth. One of those symptoms is called chlorosis.  Chlorosis is caused when the lack of chlorophyll in the leaves due to the Mg deficiency causes said leaves to become highly photosensitive and any increased light intensity can "scorch" them.  This gives the effect of "yellowing" of the veins within the leaves.  Magnesium as a nutrient is responsible for a large number of enzymes involved in energy transfers which control photosynthesis, respiration and some metabolic processses.  So not only does the deficiency in Mg cause chlorosis but the growth of the plant will be affected.  It is interesting to note that growth loss in magnesium deficient plants tends to happen above the surface in the shoots. 

And this is what got me thinking...

Roots allow a plant to absorb water and nutrients from the surrounding soil, and a healthy root system is key to a healthy plant. The root:shoot ratio is one measure to help assess the overall health of plants.

Plants growing under less favourable conditions could possibly have an increased root: shoot ratio campared to those with more favourable growing conditions.  If this be the case then Mg deficient trees or even other nutrient deficiencies could have a bearing on the size of the root system compared to "healthy" trees. 

Now most trees these days when planted in building/housing/transport schemes etc, IN MY OPINION, are not well thought out, are not well planted, are not well maintained.  Well I say most but i've probably tarnished a lot of people's good practice and I do apologise.  Anyway, a large majority of trees suffer the indignity of narrow minded people with big budgets for "the project" but little pockets for trees and plants as an afterthought.   Sites picked need better amelioration, and "PREVENTATIVE" procedures put in place to alliviate the urban trees plight.  So if there are a lack of nutrients especially magnesium in surrounding areas then surely the roots ARE going to get bigger in order to search out the required nutrients that the shoots aren't getting for the enzymes etc to create food and resources.  Bigger roots = bigger problems for the trees in the future = tree eventually dies or gets removed...

Bit of a long winded story and I could probably get into it more but I can only do my bit and hope to change things for the better one step at a time!