49
votes
Accepted
Is there sand in Antarctica?
Yes. In fact, there are sand-dunes in Antarctica [1:15].
21
votes
Do volcanos really create fertile soil?
As always: It Depends.
Assuming enough water and sunshine, crop growth rate boils down to the concept of limiting nutrients. These may be: nitrogen (via ammonia or nitrates), phosphorous (via ...
- 1,102
14
votes
Is there sand in Antarctica?
This LiveScience article suggests the areas aren't major:
The scant areas that are free of snow and ice make up less than 0.4
percent of the continental land mass. In places there, the wind has
built ...
- 8,802
11
votes
Are there any areas on Earth with purplish-colored soil/sand/rock/land?
Soil color is highly dependant on the oxides and other minerals in the composition. Purplish tones appear to be possible by inclusion of manganese oxide compounds. There are locations in China that ...
- 111
10
votes
Impact of Sugar on the environment
Sugar can be used as a weed killer, particularly broad leaf weeds, rather than grasses or perennials. It is a carbon nutrient that contains no nitrogen. Sugar can limit the growth of plant that do not ...
- 24.8k
9
votes
Accepted
Is silicon dioxide (silica) found in all types of soil on the planet?
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 ...
- 23.1k
8
votes
Why is northern Australia unsuitable for agriculture?
Erratic Climate
Lets take Broome, Australia as our example. Broome gets 615mm of rain a year (24 inches), including 58/182/180/102mm in Dec through March. Coupled with average highs in the low 90s, ...
- 3,376
8
votes
Accepted
The fertility of the soil
From this paper from 1958 (page 2),
... gaseous nitrogen of the atmosphere represents a vast store of potential
fertility. It is not directly available to plants. Nitrogen-fixing bacteria, how-
...
- 24.8k
8
votes
What is the average color of soil?
Soil color is largely determined by it's composition.
There are three main components in soil:
Gravel, sand, and silt. In essence, the type of stuff you find in sedimentary rocks. Usually, this is ...
8
votes
Accepted
Calcareous deposits in arid soil?
Karkar is made of calcium carbonate.
then why it happens only in arid soil?
Because this is what happens to calcium carbonate in wet environments:
It dissolves away, forming a cave. Calcium ...
- 23.1k
7
votes
Are there any areas on Earth with purplish-colored soil/sand/rock/land?
Yes, there are. Here are some examples from Southern Israel:
Another exceptional example is the "rainbow mountain" in Peru:
The cause of these colours is the usually trace oxide amount in the soil. ...
- 23.1k
6
votes
How can poor tropical soils be enriched by biological means?
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 ...
- 521
6
votes
Accepted
What is the residue after plant matter is completely decomposed?
From Mary, et al., 1996, Figure 1 on the second page shows a nice breakdown of there the Carbon and Nitrogen go when a plant decomposes. Hadas, et al., 2002 has experimental data from plants with C:N ...
- 3,376
5
votes
Accepted
How to identify a landslide area early?
Curved trees are a sure sign of movement of surface. Special geomorphic shapes are also present in a slowly developing landslide. At the top of the landslide cracks can start to show, at the foot you ...
- 156
5
votes
Accepted
What is the difference between lunar and earth soil
The single biggest difference is the lack of chemical weathering in lunar soils which are subject to physical weathering almost exclusively. If you exclude biological processes, terrestrial rocks ...
- 2,813
5
votes
How can poor tropical soils be enriched by biological means?
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 ...
- 283
5
votes
The fertility of the soil
What does 'nitrogen' mean?
Nitrogen might mean gaseous $N_2$. It might also mean compounds, which contain nitrogen, such as nitrate, ammonia and ammonium.
$N_2$
$N_2$ cannot be metabolized by most ...
- 2,681
5
votes
Why is northern Australia unsuitable for agriculture?
Kingledion's answer speaks to the challenges of the soil and climate for agriculture in northern Australia. However, it seems there is nevertheless significant untapped potential.
Arable Soil
The ...
- 231
5
votes
Peaty soil vs laterite soil
I didn't study tropical soils in any depth, but I've studied quite a bit about wetland soils. In my experience most peaty soils are waterlogged, which would encourage anoxia and prevent decay. ...
- 91
4
votes
Is it true that aquaponics yield crops with a lower nutritional value than soil-agriculture?
First look at the article, is cites no sources and is not written by an an expert. It is written without peer review and does not seem to understand how to measure nutritional content (brix is only a ...
- 7,026
4
votes
Accepted
Soil metals acids and bases
Most alkali and alkaline earth metals, especially the most abundant ones calcium, magnesium, potassium and sodium (list is alphabetical) exist in silicates. Silicic acid/hydrated silica is very weakly ...
- 4,041
4
votes
Does the diameter of the earth decrease because of soil subsiding due to irrigation and rainfall over the years?
Disclaimer: this is probably TLWR, but you can absolutely apply some physical reasoning to arrive at the answer.
Changes in surface height of the earth are governed by the conservation of mass, i.e. ...
- 432
4
votes
does silt form from sand ; does clay form from silt
Sand to silt is a physical process, silt to clay is most often a chemical process.
Sand and larger rocks are physically weathered to form silt, everything from frost wedging to simple abrasion.
...
- 7,026
4
votes
The origin of permafrost
What caused a centuries long freeze, the beginning of the current ice age. Yes we are in an ice age, as long as greenland and antarctica have large ice sheets we are technically in an ice age) Which ...
- 7,026
Only top scored, non community-wiki answers of a minimum length are eligible