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I am an archaeologist and I specialize in the ancient Maya. Here's how it happens: 1: The vast majority of ancient Maya buildings are built using a "core and veneer" technique. The bulk of the building's volume is earth and stone rubble, faced with a veneer of nicely-shaped limestone blocks that are themselves covered by a layer of lime plaster (stucco). ...


16

The accumulation of soil in such situations takes a long time. The main way soil would have been naturally transported there would be by the wind. The wind blown soil would get caught and accumulate. Plants, particularly grasses, would grow on the soil and the plant roots would create mesh that would protect the soil from erosion. You are correct in that ...


6

tl;dr Silica is everywhere, in everything. The amounts can be close to 100% in quartz sand, or less than 1% in things like peat or limestones (and derived soils). Finding completely pure soils (let's say less than 0.1%) is wishful thinking. Silicon dioxide (or silica, or silicon oxide, it's all the same thing) can exist in two "forms": As the compound, ...


6

There are two main problems that "wear out" soil, and people working on this deal with both of them. A soil might be low in organic matter and nitrogen, perhaps because all the crops were sold away and the topsoil eroded off. This would also happen on a new sandbank, or where a landslide had revealed a lot of subsoil. Naturally what happens is that the site ...


5

The greatest asset of soils in tropical regions is the organic matter rich 'O-horizon'. Check any reference on soil profiles, they will tell you a lot. Yes, the tropical climate is conducive to excessive rain and leaching of mineral nutrients and salts in upper layers of soil profile that can be observed in a well developed 'E-horizon'. Depending on the ...


5

...the process that had occurred with the flood... I'm assuming that you are talking about the biblical flood. There is no evidence that the flood had ever occurred. Can...mountains actually be Giant petrified Tree Stumps? No. Petrified trees are made of silica with a very distinct texture as observed in the microscope. All mountains are made of other ...


4

I assume you mean sensors that measure volumetric soil water content. The answer will depend on the amount of precipitation and the permeability of the soil. Soils don't reach full saturation in some climates - especially coarse texture soils. I would say that if the soil water content reaches a maximum value that persists for a period of time after large ...


4

Most of the Mexican pyramids are less steep than their Egyptian counterparts, and have niches and terraces which their Egyptian counterparts don't. An important difference is the climate, which is much damper in Mexico, and shows how the rainforest can reclaim areas where it has been eradicated if the site is then abandoned. Yet another factor is the type of ...


3

From what I've read so far, it appears jarosite may not be a prerequisite for the formation of certain life forms, instead that it is produced by certain organisms. Río Tinto (Huelva, southwestern Spain) is an extreme environment with a remarkably constant acidic pH and a high concentration of heavy metals, conditions generated by the metabolic activity ...


2

Organic matter affects the pH and makes the soil more acidic. The best example of this is in peat bogs, where only acid tolerant plants can live and the peat is so acidic that micro-organisms don't flourish, thus preventing decay. There is the famous Tollund Man, found in a peat bog in Denmark if I remember rightly. The body is in an almost perfect state of ...


2

Just as there are many different rocks and soils on Earth, so there are many different rocks and soils on Mars. To reproduce a Martian soil, you need to bear two things in mind. Firstly it should have all the vital nutrients plants need to grow, and secondly it should have no component of biological origin. That rules out limestone for a start. Your soil ...


2

Disclaimer: this answer is based on what I remember from school and TV. When a volcano erupts with lava flows, the magma cools and forms an inhospitable, sterile surface. The first life to colonise the rocky surface is lichens. When the lichens start dying, they decay into very thin soil layers. Next comes moss which needs a tiny bit of soil. The roots of ...


1

Fundamentally it doesn't make sense to describe the point scale model with hillslope length and drainage density. If you are looking to model a soil column, you could use Darcy's law or Richard's equation. If you are looking to model the catchment, the point scale is not appropriate, although you could always incorporate those point-scale appropriate ...


1

The pressure as measured at a point z+dz (dz infinitesimally small) and z. At the surface, pressure is the atmospheric pressure. Just below the surface, let's say at 1 cm depth, pressure is atmospheric pressure + whatever weight of the water column (taking into account saturation and so on). If the pressure gradient is in equilibrium with the gravity, you ...


1

The Accumulation of organic detritus begins when a structure is abandoned or poorly maintained. Plants that thrive without soil (epiphytes, lithophytes) are often the first generation of plants. As they die, new ones take their place and the first layer of accumulated biomass builds to accommodate more sophisticated plants grow in this medium


1

You're the man who grows coconuts and had a small problem with mimosa plants which you now intend to compost. Don't forget that coconut fronds blown down by the wind and any other waste products from the palms can all go into your compost. In England, earthworms are highly valued in the compost heap, as they help the vegetation break down more efficiently, ...


1

Here is some supplemental material for the good answer above. It won’t let me comment, http://www.fao.org/docrep/x5871e/x5871e04.htm


1

There are two ways carbon is released from soil. The first is cellular respiration of plants that uses previously stored energy (visualized in this chart). The second is when heterotrophs consume organic carbon below ground and respire carbon dioxide. The sum of these is called soil respiration, which I think was the process you were asking about.


1

Soil enrichment by biological means involves getting biological/organic material into the soil. The organic fraction of a soil profile is called humus. This is a natural process but it can be introduced into agriculture by plowing in crop stubble and other vegetation, whether green or dry. This process can also involve soil conditioning. Conditioning agents ...


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