4 questions on soil formation processes?

[jones123]

1) What makes the difference if a soil will leach out completely or a soil where clay or other material illuviation will take place?
2) Why are podzolic soils acidic?
3) Why is there an upward movement of groundwater in arid areas (what causes this)?
4) Why is kaolinite often formed at the base of tropical soils?

Thanks!

[Ophiolite]

This looks like homework. The policy here is that members will happily help you with your homework, but you have to show some evidence that attempted to determine the answers yourself. This is based on the presumption that when you grow up you may actually want to earn a living. Throw in some evidence you have made some attempt to answer and I am sure help will be forthcoming.

 

But thank you for saying thanks.

[jones123]

This looks like homework. The policy here is that members will happily help you with your homework, but you have to show some evidence that attempted to determine the answers yourself. This is based on the presumption that when you grow up you may actually want to earn a living. Throw in some evidence you have made some attempt to answer and I am sure help will be forthcoming.

 

But thank you for saying thanks.

 

Okay, thank you for making that clear to me. Actually, these aren't homework questions but these are problems that I encountered while reading through my lecture notes

 

1) What makes the difference if a soil will leach out completely or a soil where clay or other material illuviation will take place?

I think this one has something to do with the nature of the sediments which build up the soil. Some minerals like calcite will easily solve when percolating water passes (soil particles will leach out completely), others are more weathering-resistant, leaving behind fine clay minerals which accumulate in the B-horizont but I'm not quite sure (= luvisols).

 

2) Why are podzolic soils acidic?

Podzolisation is the process in which acidic organic matter-metal complexes are formed, which then move downward in the soil. I'm not sure if it is the presence of this organic matter that makes the soil acidic (I'd say that because they move downward the acidity will as well) or other processes?

 

3) Why is there an upward movement of groundwater in arid areas (what causes this)?

I think this has to do something with capillary forces being larger than gravital forces. But I don't really know if this is the only aspect influencing this proces

 

4) Why is kaolinite often formed at the base of tropical soils?

Probably due to high and intensive rainfall and percolation of dissolved soil particles, leaving clay minerals behind (ferralsols, ...), but then what's the difference with luvisols because clay accumulation is much deeper in tropical areas?

 

I hope this wil prove you some evidence that I did try to answer these questions