TopHorizon Or 'A'Horizon.
2006-12-26 01:22:14 · 7 answers · asked by abhinav r 1 in Science & Mathematics ➔ Earth Sciences & Geology
the top horizon of soil is "top soil" or "the crust"
it consits of organic materials such as dead leaves, dead animals,,,,,etc .it is well known for it's fertility. plants can grow only in this horizon
2006-12-26 17:13:21 · answer #1 · answered by SAMS 2 · 0⤊ 0⤋
Well in the most simple terms a surface horizon that is mineral soil will be an A horizon, if it is mostly organic it is an O.
There are cases where the original A horizon has been removed (massive erosion, flooding etc.) but the remaining soil is still there. The original soil situation will be included in description as combo horizons. IE. a exposed B = A/B, especially if the B has been plowed Ap/B. Ap/E is a common topsoil horizon in the SE US because of poor agricultural practices 200 years ago
2006-12-26 20:23:02 · answer #2 · answered by Eric D Redd 2 · 1⤊ 0⤋
I know a little about soil horizons, but googled it to be sure of my facts. The following is from the University of Minnesota:
Surface soil horizons are mainly influenced by the addition of organic matter. The organic matter that is added to a soil will first be undecomposed. Gradually organisms in the soil will begin to decompose this litter until it is no longer recognizable as leaves. Eventually this organic matter is decomposed so much it becomes colloidal in size and coats the mineral particles of the soil.
O-horizons are all organic matter and are mainly found in forest soils where the yearly addition of leaves builds up a layer of undecomposed leaves. In fact, the O horizon contains very little mineral soil.
The A horizon is a mineral horizon that is dark in color due to the incorporation of decomposed organic matter, which coats the mineral soil particles with colloidal size organic matter.
2006-12-26 09:31:21 · answer #3 · answered by peter_lobell 5 · 1⤊ 0⤋
The top horizon of soil is the Surface soil or fresh soil. it consists of leaves and litter.
2006-12-26 14:12:28 · answer #4 · answered by drishti 2 · 0⤊ 0⤋
The only thing I know of is called the "top soil"
2006-12-26 09:26:05 · answer #5 · answered by Anonymous · 0⤊ 0⤋
THE TOP HORIZON OF SOIL IS CALLED THE FERTILE SOIL.
2006-12-26 09:24:23 · answer #6 · answered by Anonymous · 0⤊ 0⤋
its organic horizon... it will be black in colour... if its not black it is A horizon...
2006-12-27 06:05:02 · answer #7 · answered by chandra sekaran.p 2 · 0⤊ 0⤋