Plant Leaves Left On Soil
Many plants produce organic acids. Where plant litter accumulates on or is incorporated to the soil, these acids (including acetic acid, humic acid (see http://www.suprahumic.unina.it/), oxalic acid, and tannic acid) are liberated. This is especially acute in soils under coniferous trees such as pine, spruce and fir, which return fewer base cations to the soil than do most deciduous trees.
Read more about this topic: Soil Acidification
Famous quotes containing the words plant, leaves, left and/or soil:
“Though I do not believe that a plant will spring up where no seed has been, I have great faith in a seed,—a, to me, equally mysterious origin for it.”
—Henry David Thoreau (1817–1862)
“The best history is but like the art of Rembrandt; it casts a vivid light on certain selected causes, on those which were best and greatest; it leaves all the rest in shadow and unseen.”
—Walter Bagehot (1826–1877)
“What’s this, Aurora Leigh,
You write so of the poets and not laugh?
Those virtuous liars, dreamers after dark,
Exaggerators of the sun and moon,
And soothsayers in a tea-cup? I write so
Of the only truth-tellers, now left to God,—
The only speakers of essential truth,
Opposed to relative, comparative,
And temporal truths;...
The only teachers who instruct mankind,
From just a shadow on a charnel-wall.”
—Elizabeth Barrett Browning (1806–1861)
“But men labor under a mistake. The better part of the man is soon ploughed into the soil for compost. By a seeming fate, commonly called necessity, they are employed, as it says in an old book, laying up treasures which moth and rust will corrupt and thieves break through and steal. It is a fool’s life, as they will find when they get to the end of it, if not before.”
—Henry David Thoreau (1817–1862)