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Micronutrients are essential elements that are needed only in small quantities, but can still be limiting to plant growth since these nutrients are not so abundant in nature. Micronutrients include iron (Fe), manganese (Mn), boron (B), molybdenum (Mo), chlorine (Cl), zinc (Zn), and copper (Cu). There are some other elements that tend to aid plant growth but are not absolutely essential.

Micronutrients and macronutrients are desirable in particular concentrations and can be detrimental to plant growth when concentrations in soil solution are either too low (limiting) or too high (toxicity). Elemental nutrients are useful to plants only if they are in an extractable form in soil solutions, such as an exchangeable cation, rather than in a solid mineral grain. As nutrients are used up in the microenvironment surrounding a plant's roots, the replenishment of nutrients in soil solution is dependent on three aspects: (a) the rate of dissolution/alteration of soil minerals into elemental constituents, (b) the release rate of organically bound nutrients, and (c) the rate of diffusion of nutrients through the soil solution to the area of root uptake.

Many nutrients move through the soil and into the root system as a result of concentration gradients, moving by diffusion from high to low concentrations. However, some nutrients are selectively absorbed by the root membranes, such that elemental concentrations of solutions within plants may differ from that in soil solutions. Most nutrients exist as exchangeable cations that are acquired by roots from the soil solution—rather than from mineral or particle surfaces. Inorganic chemical processes and organic processes, such as the action of soil microorganisms, can help to release elemental nutrients from mineral grains into the soil environment.

Soil health and agricultural impacts: soil as a sustainable resource

Soil health and sustainability

Overall soil health can generally be defined as the capacity of the soil to function in a way that infiltrates water and cycles nutrients to support plant growth. Long term health of native soil is in many cases improved by disturbing the soil less, growing a greater diversity of crops, maintaining living roots in the soil, and keeping the soil covered with residue. Stable soil aggregates are important for soil health as they promote proper infiltration and thus limit the amount of water runoff —this has the added benefit of reducing soil erosion and downstream flooding and sedimentation.

Management of soil on farms may include use of tillage, fertilizer, pesticides, and other tools that may improve soil health if used correctly; however, significant damage to soil may result otherwise. Tillage with a plow or disk is can be physically disruptive to soil fauna and microbes. The complex relations between soil and plant life, which have evolved into a sustainable relationship in the natural world, can be disturbed chemically by misuse or overuse of fertilizers or pesticides. Thus, to maintain soil health, one needs to understand the chemical, biological, and physical processes that operate in the natural soil profile. To the extent possible, we must work with the complexity of processes that function in a healthy soil and limit our disturbances to only those that are clear, practical necessity. Biodiversity is another important aspect to consider, because increasing the biodiversity of plants that are grown in soil can limit disease and pest problems and allow for a better functioning food web. More diversity in plants above ground leads to more diversity in the subsurface food web. Consequently, increasing the diversity of appropriate crop rotation in agricultural lands can ultimately lead to better soil health and limit problems in the long run.

Questions & Answers

Do somebody tell me a best nano engineering book for beginners?
s. Reply
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
how to fabricate graphene ink ?
for screen printed electrodes ?
What is lattice structure?
s. Reply
of graphene you mean?
or in general
in general
Graphene has a hexagonal structure
On having this app for quite a bit time, Haven't realised there's a chat room in it.
what is biological synthesis of nanoparticles
Sanket Reply
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
types of nano material
abeetha Reply
I start with an easy one. carbon nanotubes woven into a long filament like a string
many many of nanotubes
what is the k.e before it land
what is the function of carbon nanotubes?
I'm interested in nanotube
what is nanomaterials​ and their applications of sensors.
Ramkumar Reply
what is nano technology
Sravani Reply
what is system testing?
preparation of nanomaterial
Victor Reply
Yes, Nanotechnology has a very fast field of applications and their is always something new to do with it...
Himanshu Reply
good afternoon madam
what is system testing
what is the application of nanotechnology?
In this morden time nanotechnology used in many field . 1-Electronics-manufacturad IC ,RAM,MRAM,solar panel etc 2-Helth and Medical-Nanomedicine,Drug Dilivery for cancer treatment etc 3- Atomobile -MEMS, Coating on car etc. and may other field for details you can check at Google
anybody can imagine what will be happen after 100 years from now in nano tech world
after 100 year this will be not nanotechnology maybe this technology name will be change . maybe aftet 100 year . we work on electron lable practically about its properties and behaviour by the different instruments
name doesn't matter , whatever it will be change... I'm taking about effect on circumstances of the microscopic world
how hard could it be to apply nanotechnology against viral infections such HIV or Ebola?
silver nanoparticles could handle the job?
not now but maybe in future only AgNP maybe any other nanomaterials
I'm interested in Nanotube
this technology will not going on for the long time , so I'm thinking about femtotechnology 10^-15
can nanotechnology change the direction of the face of the world
Prasenjit Reply
At high concentrations (>0.01 M), the relation between absorptivity coefficient and absorbance is no longer linear. This is due to the electrostatic interactions between the quantum dots in close proximity. If the concentration of the solution is high, another effect that is seen is the scattering of light from the large number of quantum dots. This assumption only works at low concentrations of the analyte. Presence of stray light.
Ali Reply
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Sustainability: a comprehensive foundation. OpenStax CNX. Nov 11, 2013 Download for free at http://legacy.cnx.org/content/col11325/1.43
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