Questions tagged [soil]
For questions about the outermost layer of the surface of the Earth. The soil is saturated with organic remains and rock particles.
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Reading a Soil Size Distribution Diagram
I have the Soil Size Distribution Diagram shown below from a source that does not specify the meaning of the labels A1=60, A2=50, and A3=50. I understand that it is data for three different samples, ...
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Is it possible/effective to synthetically produce chernozem soil?
Chernozem soils, called mollisols in the Americas, are black-colored soils containing a high percentage of humus (4% to 16%) and high percentages of phosphorus and ammonia compounds. Many earthworms ...
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Geotechnology: Prove a formula, calculated with unit weights, for void ratio
I don't know where else to post this.
I am reading a Geotechnical engineering textbook by B.M. Das, 6th edition.
Problem 3.1 is as follows:
For a given soil, show that
$$e=\frac{\gamma_{sat} - \...
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Reason for finding low boron levels in clayey soil with high organic matter?
I've read from various University Extension sites (e.g., here and here) that boron levels would be deficient in sandy soils with low organic matter.
This would suggest that boron levels would be ...
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Causes of high calcium levels in sandy alluvial soils
When soil calcium is high: High levels of soil calcium may be expected when there is substantial calcium carbonate bedrock from which the soil has weathered. Calcium levels can be high in agricultural ...
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Searching for Geochemical Threshold for PTE's of Spain
Where can I find a table with the geochemical threshold for potentially toxic elements in the soils of Spain? I only have seen a decree with organic compounds for Spain.
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How do housing developments affect the soil of the surroundings? Are the minerals/molecules in cement available to plants? Or is the soil too basic?
Calcium carbonate in cement can make the soil more alkaline but does that make large housing developments have a significant or negligible affect on availability of nutrients? Does it cause nutrients ...
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How to define the lower boundary conditions: seepage face and unit gradient in terms of soil volumetric water content?
context: the models that simulate the flow of water in the soil (e.g. land-surface models)
In these models, in order to simulate percolation (/drainage) from the bottom of the defined soil column, we ...
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Why is the soil between these olive trees left bare?
These photos were taken this week in the Tarragona province of Spain which is also seeing a heat wave at the moment. One can also see farmers using cultivators removing what were wild weeds that grew ...
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How is layer compaction degree designed to be ≥90% in lower layers and ≥ 95% in the upper 5 ft in a railway embankment?
I am currently working at the Tren Maya project in México as part of the planing department; anyways I studied a Masters degree, and looking at the executive project, there are some parameters I’ve ...
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Signs of hydrocarbon contamination in soil?
So, let's say, ~completely theoretically~ you knew, beyond a reasonable doubt, a large oil company was doing something nefarious near you. They own a very strange property through a shell company. Now,...
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Can I use building gypsum as a soil additive? [closed]
So, I am mixing up a substrate from peat and perlite,50%/50%, and I am adding some dolomite lime and gypsum as additives, as vermaculite is too expensive to substitute for the perlite.
As I am unable ...
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Global gridded Leaf Area Index and Soil Depth data for hydrological analysis - references and unmixing by land use
I am working with a global fully distributed (gridded) hydrological model and I am having some issues regarding two sets of data extremely important for the correct representation of the soil ...
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How does manure & other organic matter improve soil structure?
How does manure & other organic matter improve soil structure? Based on my understanding, soil structure refers to the arrangement of the aggregates within the soil; a good soil structure prevents ...
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Where can I find soil Free Swell Index values for the Cambridgeshire region, United Kingdom?
Where can I find Free Swell Index data for Clays for the Cambridgeshire region, United Kingdom?
Surely this must have been performed at some point even though there are more sophisticated tests. I've ...
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What would be the effects of a large forest fire on soil in other places?
Say a large forest fire took place. As I understand it, the smoke and ash would ride the wind and could be a health hazard even to people that are quite far away.
My question is will it damage the ...
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"Down wash" as a source for mineral particles in the soil
In a previous IGCSE examination paper$^1$, the following question was asked and answer provided:
State one source of mineral particles in soil.
Marking Scheme:
Accept any one of:
rock;
down wash;
...
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Is there a more accurate method for estimating ground or soil temperatures
Context
We have geothermal, engineering and construction clients who often need accurate estimates of ground temperatures for project sites before they have physical access to the sites (for ...
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Generalized Soil Unit Information on Soil Characteristics of FAO/UNESCO Soil Map
I have some doubts regarding the FAO/UNESCO Soil Map of the World. I have downloaded the ESRI shapefile format of Digital Soil Map of the World (3rd download link on this page).
Among other files, ...
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How to Distribute Soil moisture output of Thornthwaite and Mather (1954) Soil Water Balance Model into different layers?
in Thornthwaite & Mather (1954) Soil Water Balance Approach
The soil moisture output is generated for the whole soil profile, i.e whatever depth we take for the ...
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Impact of Sugar on the environment
i hope this question fits here.
In my local nature reserve there is an "art" project... but the local population has it's concerns.
Seeing most things seem to be random trash thrown in (like ...
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Normalized Difference Vegetation Index sensitivity to soil
A lot of papers mention that Normalized Difference Vegetation Index (NDVI) is sensitive to soil background such as bare soil. My question is what is the exact reason behind the impact of soil on NDVI?
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USDA soil classification vs FAO/UNESCO soil classification
I am making a global social media website for farmers and gardeners which can be used to share information about plant varieties. This sharing is done via so called garden journals.
In a garden ...
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Do long-term anaerobic conditions caused by flood-irrigation lead to irreversible soil degradation?
In fields that have been cultivated with rice, frequent flood irrigation can lead to soil degradation.
When this type of cultivation has been implemented for several decades, will the soil suffer from ...
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How fast does sand degrade into silt, and silt into clay?
I am talking to some students about how soil changes, and I've heard from soil samplers that the texture of the soil, i.e. whether it is sand, silt or clay, doesn't change in a human lifetime. It ...
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How deep is soil?
I am curious of the lower boundary of soil. Soil is formed after going through complex processes and it has been through coevolution with living organisms. According to the USDA, for soil ...
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sub soil data finding
I am going to search and finding some subsoil data, (vanGenuchten Parameters, specific storage, Hydraulic conductivity, porosity, Manning coefficient and humidity of root zone) I have no idea about ...
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What method do I use to derive the organic material content (as a percentage) per layer in SoilGrids
I am doing soil related calculations for moisture content and the soil characteristics I need (among others) is the content of the soil as a percentage for:
sand
clay
organic matter
I am thinking I ...
Eric Laukonen
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Looking for variables to compare against pH of soil
I'm doing a project in junior year chemistry where I get to choose what I investigate as long as it covers course content. I'm interested in exploring how quantitative (ig. incremental) change in an ...
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SC7 and SC10 Lithology Classifications
I am looking for the full names of the lithology classifications SC7 and SC10. According to the FAO's guidelines for soil description SC3 e.g. refers to silt-, mud-, claystone. What do SC7 and SC10 ...
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What kind of soil is being worked in this video? [closed]
I have recently stumbled across this video on Youtube, where quite a magnificient building is carved into the soil with simple tools like a shovel and hoe. The location is somewhere in South America, ...
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Is it normal for clay soil to solidify into a very hard, but not brittle, material in air, and if not what might this soil be?
One part of my garden has a heavy, dark clay soil. It is now waterlogged with a lot of surface water that does not shift at all even after a day of waiting. When pressed into a 4mm thick ribbon, it ...
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How does fertile soil reach newborn volcanic islands?
When a volcanic island first surfaces, I assume no vegetation can grow, as it probably only consists of volcanic rock.
How would a volcanic island like Iceland that is far from any continent grow to ...
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What is the connection (if any) between jarosite and subsoil biological activity near Spain's Río Tinto?
In the short BBC video Spain's otherworldly red river, Ricardo Amils, a researcher in Spain's Astrobiology Center says the following (amateur transcription):
Río Tinto is a peculiar place in our ...
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How to make Martian soil [duplicate]
My son wants to replicate some experiments and try to grow plants in Martian soil for his A-level science project. I know NASA have managed to produce soil that mimics Martian soil, however I also ...
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How to make Martian soil
My son wants to replicate some experiments and try to grow plants in Martian soil for his A-level science project. I know NASA have managed to produce soil that mimics Martian soil, however I also ...
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How is soil thickness related to altitude, angle and moisture?
I'm trying to generate a landscape and I want to include soil thickness for realism. Data I have is altitude, angle of a given point and moisture of a given point.
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The origin of permafrost
Old permafrost is loaded with frozen vegetation. As it now melts, it is rotting and releasing methane.
Doesn't that mean that it froze quickly, centuries ago, and stayed frozen until now?
What ...
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solubility of rare earth sulphides at different pH?
Will rare earth sulfides in soil be more soluble in aqueous solutions with lower pH? How can I know whether these sulfides will dissolve better at low or high pH or will it not be affected?
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does silt form from sand ; does clay form from silt
I believe that sand, silt, clay are defined by size. But are they also generated by different processes and from different materials? Alternatively do sand particles ultimately weather to make silt, ...
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What's a Good Soil Quality Index for Plowed Farm Lands?
I'm currently conducting research using Satellite/Weather/Soil (Mostly Sentinel-2 Satellite Imagery) Data to Model Smallholder Farms and their dynamics before Planting.
Key to my progress is to find ...
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Snowmelt erosion in USLE?
Is there any way to compute snow-melt erosion with Universal Soil Loss Equation? How can I change rainfall erosivity factor to snow-melt erosivity?
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Difference between soil Water Holding Capacity and soil pore volume?
I have got confused
I took 100g soil in a funnel with filter paper. poured 100 ml water and collected the drained water in a calibrated cylinder.
Water added in funnel = 100 ml
Water collected in ...
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Why is the bedrock buried so deeply in much of northern Minnesota?
Although parts of northern Minnesota have bedrock exposed at the surface (especially in the Boundary Waters area and along the short of Lake Superior), the more usual situation here is for the bedrock ...
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Where are Africa's 600 million hectares of arable land located?
According to Africas Ministers pledge to commercialise regions agricultural sector
Speaking during a ministerial roundtable meeting at the AGRF in Kigali, Rwanda, the leaders noted that the ...
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Is silicon dioxide (silica) found in all types of soil on the planet?
Known that it is found in sand, silt and clay but is it found in all soils?
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soil that is dried (no pore space) weight?
How much would 1 m3 of an ideal mineral SOIL that has been completely dried (all pore space is empty) weigh in Mg on Earth? Answer = ______ Mg
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Making a local geological field trip an interesting and educational event for children?
I have no expertise in geology or earth science, but I would like to do a "field trip" with my home-schooled young children (under age 10) where I could teach them about geology from a hands-on ...
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How many kg $ha^-$$^1$ of exchangeable $Mg^2$$^+$ is there in the top 15cm of this field?
Soil testing from a well-drained soil sample in 0-15cm depth of a farmers field provides the following
information:
• Wet weight of a soil sample from a volume of 100 $cm^3$: 200 g
• Moisture ...
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Leaching Requirement
How can we determine supplemental irrigation needed to reduce soil salinity knowing ETP of a crop and the annual precipitation?
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