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DIY Organic Potting Mix's for Grass - Ace Spicoli

acespicoli

Well-known member

Work functions of elements​

The work function depends on the configurations of atoms at the surface of the material. For example, on polycrystalline silver the work function is 4.26 eV, but on silver crystals it varies for different crystal faces as (100) face: 4.64 eV, (110) face: 4.52 eV, (111) face: 4.74 eV.[13] Ranges for typical surfaces are shown in the table below.[14]

Work function of elements (eV)
Ag
4.26 – 4.74
Al
4.06 – 4.26
As
3.75
Au
5.10 – 5.47
B
~4.45
Ba
2.52 – 2.70
Be
4.98
Bi
4.31
C
~5
Ca
2.87
Cd
4.08
Ce
2.9
Co
5
Cr
4.5
Cs
1.95
Cu
4.53 – 5.10
Eu
2.5
Fe:​
4.67 – 4.81
Ga
4.32
Gd
2.90
Hf
3.90
Hg
4.475
In
4.09
Ir
5.00 – 5.67
K
2.29
La
3.5
Li
2.9
Lu
~3.3
Mg
3.66
Mn
4.1
Mo
4.36 – 4.95
Na
2.36
Nb
3.95 – 4.87
Nd
3.2
Ni
5.04 – 5.35
Os
5.93
Pb
4.25
Pd
5.22 – 5.60
Pt
5.12 – 5.93
Rb
2.261
Re
4.72
Rh
4.98
Ru
4.71
Sb
4.55 – 4.70
Sc
3.5
Se
5.9
Si
4.60 – 4.85
Sm
2.7
Sn
4.42
Sr
~2.59
Ta
4.00 – 4.80
Tb
3.00
Te
4.95
Th
3.4
Ti
4.33
Tl
~3.84
U
3.63 – 3.90
V
4.3
W
4.32 – 4.55
Y
3.1
Yb
2.60[15]
Zn
3.63 – 4.9
Zr
4.05

List of lattice constants​

Lattice constants for various materials at 300 K
MaterialLattice constant (Å)Crystal structureRef.
C (diamond)3.567Diamond (FCC)[7]
C (graphite)a = 2.461
c = 6.708
Hexagonal
Si5.431020511Diamond (FCC)[8][9]
Ge5.658Diamond (FCC)[8]
AlAs5.6605Zinc blende (FCC)[8]
AlP5.4510Zinc blende (FCC)[8]
AlSb6.1355Zinc blende (FCC)[8]
GaP5.4505Zinc blende (FCC)[8]
GaAs5.653Zinc blende (FCC)[8]
GaSb6.0959Zinc blende (FCC)[8]
InP5.869Zinc blende (FCC)[8]
InAs6.0583Zinc blende (FCC)[8]
InSb6.479Zinc blende (FCC)[8]
MgO4.212Halite (FCC)[10]
SiCa = 3.086
c = 10.053
Wurtzite[8]
CdS5.8320Zinc blende (FCC)[7]
CdSe6.050Zinc blende (FCC)[7]
CdTe6.482Zinc blende (FCC)[7]
ZnOa = 3.25
c = 5.2
Wurtzite (HCP)[11]
ZnO4.580Halite (FCC)[7]
ZnS5.420Zinc blende (FCC)[7]
PbS5.9362Halite (FCC)[7]
PbTe6.4620Halite (FCC)[7]
BN3.6150Zinc blende (FCC)[7]
BP4.5380Zinc blende (FCC)[7]
CdSa = 4.160
c = 6.756
Wurtzite[7]
ZnSa = 3.82
c = 6.26
Wurtzite[7]
AlNa = 3.112
c = 4.982
Wurtzite[8]
GaNa = 3.189
c = 5.185
Wurtzite[8]
InNa = 3.533
c = 5.693
Wurtzite[8]
LiF4.03Halite
LiCl5.14Halite
LiBr5.50Halite
LiI6.01Halite
NaF4.63Halite
NaCl5.64Halite
NaBr5.97Halite
NaI6.47Halite
KF5.34Halite
KCl6.29Halite
KBr6.60Halite
KI7.07Halite
RbF5.65Halite
RbCl6.59Halite
RbBr6.89Halite
RbI7.35Halite
CsF6.02Halite
CsCl4.123Caesium chloride
CsBr4.291Caesium chloride
CsI4.567Caesium chloride
Al4.046FCC[12]
Fe2.856BCC[12]
Ni3.499FCC[12]
Cu3.597FCC[12]
Mo3.142BCC[12]
Pd3.859FCC[12]
Ag4.079FCC[12]
W3.155BCC[12]
Pt3.912FCC[12]
Au4.065FCC[12]
Pb4.920FCC[12]
V3.0399BCC
Nb3.3008BCC
Ta3.3058BCC
TiN4.249Halite
ZrN4.577Halite
HfN4.392Halite
VN4.136Halite
CrN4.149Halite
NbN4.392Halite
TiC4.328Halite[13]
ZrC0.974.698Halite[13]
HfC0.994.640Halite[13]
VC0.974.166Halite[13]
NbC0.994.470Halite[13]
TaC0.994.456Halite[13]
Cr3C2a = 11.47
b = 5.545
c = 2.830
Orthorhombic[13]
WCa = 2.906
c = 2.837
Hexagonal[13]
ScN4.52Halite[14]
LiNbO3a = 5.1483
c = 13.8631
Hexagonal[15]
KTaO33.9885Cubic perovskite[15]
BaTiO3a = 3.994
c = 4.034
Tetragonal perovskite[15]
SrTiO33.98805Cubic perovskite[15]
CaTiO3a = 5.381
b = 5.443
c = 7.645
Orthorhombic perovskite[15]
PbTiO3a = 3.904
c = 4.152
Tetragonal perovskite[15]
EuTiO37.810Cubic perovskite[15]
SrVO33.838Cubic perovskite[15]
CaVO33.767Cubic perovskite[15]
BaMnO3a = 5.673
c = 4.71
Hexagonal[15]
CaMnO3a = 5.27
b = 5.275
c = 7.464
Orthorhombic perovskite[15]
SrRuO3a = 5.53
b = 5.57
c = 7.85
Orthorhombic perovskite[15]
YAlO3a = 5.179
b = 5.329
c = 7.37
Orthorhombic perovskite[15]

The stability of the nonequilibrium thermodynamic state of biological systems is ensured by the continuous alternation of phases of energy consumption and release through controlled reactions of synthesis and cleavage of ATP.

The following consequences follow from this law:

1. In living organisms, no process can occur continuously, but must alternate with the opposite direction: inhalation with exhalation, work with rest, wakefulness with sleep, synthesis with cleavage, etc.

2. The state of a living organism is never static, and all its physiological and energy parameters are always in a state of continuous fluctuations relative to the average values both in frequency and amplitude.

This principle of functioning of living organisms provides them with the properties of phenotypic adaptation and a number of others.

 
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acespicoli

Well-known member

The main provisions of the theory of thermodynamics of biological systems​

A living organism is a thermodynamic system of an active type (in which energy transformations occur), striving for a stable nonequilibrium thermodynamic state. The nonequilibrium thermodynamic state in plants is achieved by continuous alternation of phases of solar energy consumption as a result of photosynthesis and subsequent biochemical reactions, as a result of which adenosine triphosphate (ATP) is synthesized in the daytime, and the subsequent release of energy during the splitting of ATP mainly in the dark. Thus, one of the conditions for the existence of life on Earth is the alternation of light and dark time of day.

Light
Dark



Adenosine-5'-triphosphate
Adenosine triphosphate (ATP) is a nucleoside triphosphate[2] that provides energy to drive and support many processes in living cells, such as muscle contraction, nerve impulse propagation, and chemical synthesis. Found in all known forms of life, it is often referred to as the "molecular unit of currency" for intracellular energy transfer.[3]

1731412818770.png

? The answer is ?


Plants take up phosphorus through several pathways: the arbuscular mycorrhizal pathway and the direct uptake pathway.
1731413632365.png

Arbuscular mycorrhiza is a type of endomycorrhiza along with ericoid mycorrhiza and orchid mycorrhiza (not to be confused with ectomycorrhiza). They are characterized by the formation of unique tree-like structures, the arbuscules.[1]
 
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acespicoli

Well-known member
1731413918602.png

1731414133606.png


Plants harvest electrons through a process called photosynthesis, where sunlight energy is absorbed by chlorophyll molecules within chloroplasts, causing electrons to become excited and "jump" to a higher energy level, effectively "harvesting" them from water molecules which are then split to provide a source of electrons for the plant's electron transport chain; this process releases oxygen as a byproduct.



Key points about plant electron harvesting:
  • Chlorophyll:
    The primary pigment responsible for capturing light energy, when excited by a photon of light, it donates an electron.



  • Photosystems:
    Specialized protein complexes within chloroplasts where the light energy is captured and electrons are transferred.



  • Water splitting:
    In plants, the electrons harvested come from the splitting of water molecules, releasing oxygen as a byproduct.



  • Electron transport chain:
    Once excited, the electrons are passed through a series of electron carriers within the chloroplast membrane, generating a proton gradient which is used to produce ATP.

 

acespicoli

Well-known member
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“A plant absorbs water with nutrients from the roots, but it can't consume those immediately. That's why these nutrients travel to the leaves. That’s where the plant converts them into a usable form (like sugars and amino acids) with sunlight. These then travel back to the roots and through the rest of the plant to feed them,” summarized Frank.

 
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acespicoli

Well-known member
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Food web control​

Bottom-up effects​

Bottom-up effects occur when the density of a resource affects the density of its consumer.[11] For example, in the figure above, an increase in root density causes an increase in herbivore density that causes a corresponding increase in predator density. Correlations in abundance or biomass between consumers and their resources give evidence for bottom-up control.[11] An often-cited example of a bottom-up effect is the relationship between herbivores and the primary productivity of plants. In terrestrial ecosystems, the biomass of herbivores and detritivores increases with primary productivity. An increase in primary productivity will result in a larger influx of leaf litter into the soil ecosystem, which will provide more resources for bacterial and fungal populations to grow. More microbes will allow an increase in bacterial and fungal feeding nematodes, which are eaten by mites and other predatory nematodes. Thus, the entire food web swells as more resources are added to the base.[11] When ecologists use the term, bottom-up control, they are indicating that the biomass, abundance, or diversity of higher trophic levels depend on resources from lower trophic levels.[10]

Top-down effects​

Ideas about top-down control are much more difficult to evaluate. Top-down effects occur when the population density of a consumer affects that of its resource;[10] for example, a predator affects the density of its prey. Top-down control, therefore, refers to situations where the abundance, diversity or biomass of lower trophic levels depends on effects from consumers at higher trophic levels.[10] A trophic cascade is a type of top-down interaction that describes the indirect effects of predators. In a trophic cascade, predators induce effects that cascade down food chain and affect biomass of organisms at least two links away.[10]

The importance of trophic cascades and top-down control in terrestrial ecosystems is actively debated in ecology (reviewed in Shurin et al. 2006) and the issue of whether trophic cascades occur in soils is no less complex[12] Trophic cascades do occur in both the bacterial and fungal energy channels.[13][14][15] However, cascades may be infrequent, because many other studies show no top-down effects of predators.[16][17] In Mikola and Setälä’s study, microbes eaten by nematodes grew faster when they were grazed upon frequently. This compensatory growth slowed when the microbe feeding nematodes were removed. Therefore, although top predators reduced the number of microbe feeding nematodes, there was no overall change in microbial biomass.

Besides the grazing effect, another barrier to top down control in soil ecosystems is widespread omnivory, which by increasing the number of trophic interactions, dampens effects from the top. The soil environment is also a matrix of different temperatures, moistures and nutrient levels, and many organisms are able to become dormant to withstand difficult times. Depending on conditions, predators may be separated from their potential prey by an insurmountable amount of space and time.

Any top-down effects that do occur will be limited in strength because soil food webs are donor controlled. Donor control means that consumers have little or no effect on the renewal or input of their resources.[10] For example, aboveground herbivores can overgraze an area and decrease the grass population, but decomposers cannot directly influence the rate of falling plant litter. They can only indirectly influence the rate of input into their system through nutrient recycling which, by helping plants to grow, eventually creates more litter and detritus to fall.[18] If the entire soil food web were completely donor controlled, however, bacterivores and fungivores would never greatly affect the bacteria and fungi they consume.

While bottom-up effects are no doubt important, many soil ecologists suspect that top-down effects are also sometimes significant. Certain predators or parasites, when added to the soil, can have a large effect on root herbivores and thereby indirectly affect plant fitness. For example, in a coastal shrubland food chain the native entomopathogenic nematode, Heterorhabditis marelatus, parasitized ghost moth caterpillars, and ghost moth caterpillars consumed the roots of bush lupine. The presence of H. marelatus correlated with lower caterpillar numbers and healthier plants. In addition, the researchers observed high mortality of bush lupine in the absence of entomopathogenic nematodes. These results implied that the nematode, as a natural enemy of the ghost moth caterpillar, protected the plant from damage. The authors even suggested that the interaction was strong enough to affect the population dynamics of bush lupine;[19] this was supported in later experimental work with naturally-growing populations of bush lupine.[20]

Top down control has applications in agriculture and is the principle behind biological control, the idea that plants can benefit from the application of their herbivore’s enemies. While wasps and ladybugs are commonly associated with biological control, parasitic nematodes and predatory mites are also added to the soil to suppress pest populations and preserve crop plants. In order to use such biological control agents effectively, a knowledge of the local soil food web is important.


 

acespicoli

Well-known member
This table includes some familiar types of soil life of soil life,[8] coherent with prevalent taxonomy as used in the linked Wikipedia articles.


DomainKingdomPhylumClassOrderFamilyGenus
ProkaryoteBacteriaPseudomonadotaBetaproteobacteriaNitrosomonadalesNitrosomonadaceaeNitrosomonas
ProkaryoteBacteriaPseudomonadotaAlphaproteobacteriaHyphomicrobialesNitrobacteraceaeNitrobacter
ProkaryoteBacteriaPseudomonadotaAlphaproteobacteriaHyphomicrobialesRhizobiaceaeRhizobium[a]
ProkaryoteBacteriaPseudomonadotaGammaproteobacteriaPseudomonadalesAzotobacteraceaeAzotobacter
ProkaryoteBacteriaActinomycetotaActinomycetia
ProkaryoteBacteria"Cyanobacteria (Blue-green algae)
ProkaryoteBacteriaBacillotaClostridiaClostridialesClostridiaceaeClostridium
EukaryoteFungiAscomycotaEurotiomycetesEurotialesTrichocomaceaePenicillium
EukaryoteFungiAscomycotaEurotiomycetesEurotialesTrichocomaceaeAspergillus
EukaryoteFungiAscomycotaSordariomycetesHypocrealesNectriaceaeFusarium
EukaryoteFungiAscomycotaSordariomycetesHypocrealesHypocreaceaeTrichoderma
EukaryoteFungiBasidiomycotaAgaricomycetesCantharellalesCeratobasidiaceaeRhizoctonia
EukaryoteFungiZygomycotaZygomycetesMucoralesMucoraceaeMucor
EukaryoteSAR (clade)HeterokontophytaBacillariophyceae (Diatomea algae)
EukaryoteSAR (clade)HeterokontophytaXanthophyceae (Yellow-green algae)
EukaryoteAlveolata (clade)Ciliophora
EukaryoteAmoebozoa (clade)
EukaryotePlantaeChlorophyta (green algae)Chlorophyceae
EukaryoteAnimaliaNematoda
EukaryoteAnimaliaRotifer
EukaryoteAnimaliaTardigrada
EukaryoteAnimaliaArthropodaEntognathaCollembola
EukaryoteAnimaliaArthropodaArachnidaAcarina
EukaryoteAnimaliaArthropodaArachnidaPseudoscorpionida
EukaryoteAnimaliaArthropodaInsectaCholeoptera (larvae)
EukaryoteAnimaliaArthropodaInsectaColeopteraCarabidae (Ground beetles)
EukaryoteAnimaliaArthropodaInsectaColeopteraStaphylinidae (Rove beetle)
EukaryoteAnimaliaArthropodaInsectaDiptera (larvae)
EukaryoteAnimaliaArthropodaInsectaHymenopteraFormicidae (Ant)
EukaryoteAnimaliaArthropodaChilopoda (Centipede)
EukaryoteAnimaliaArthropodaDiplopoda (Millipede)
EukaryoteAnimaliaArthropodaMalacostracaIsopoda (woodlouse)
EukaryoteAnimaliaAnnelidaClitellataHaplotaxidaEnchytraeidae
EukaryoteAnimaliaAnnelidaClitellataHaplotaxidaLumbricidae
EukaryoteAnimaliaMolluscaGastropoda
Nitrobacter is a genus comprising rod-shaped, gram-negative, and chemoautotrophic bacteria.[1] The name Nitrobacter derives from the Latin neuter gender noun nitrum, nitri, alkalis; the Ancient Greek noun βακτηρία, βακτηρίᾱς, rod. They are non-motile and reproduce via budding or binary fission.[2][3] Nitrobacter cells are obligate aerobes and have a doubling time of about 13 hours.[1]

Nitrobacter play an important role in the nitrogen cycle by oxidizing nitrite into nitrate in soil and marine systems.[2] Unlike plants, where electron transfer in photosynthesis provides the energy for carbon fixation, Nitrobacter uses energy from the oxidation of nitrite ions, NO2−, into nitrate ions, NO3−, to fulfill their energy needs. Nitrobacter fix carbon dioxide via the Calvin cycle for their carbon requirements.[1] Nitrobacter belongs to the Alphaproteobacteria class of the Pseudomonadota.[3][4]
 

acespicoli

Well-known member
The soil biomantle can be described and defined in several ways. Most simply, the soil biomantle is the organic-rich bioturbated upper part of the soil, including the topsoil where most biota live, reproduce, die, and become assimilated. The biomantle is thus the upper zone of soil that is predominantly a product of organic activity and the area where bioturbation is a dominant process.

Soil bioturbation consists predominantly of three subsets: faunalturbation (animal burrowings), floralturbation (root growth, tree-uprootings), and fungiturbation (mycelia growth). All three processes promote soil parent material destratification, mixing, and often particle size sorting, leading with other processes to the formation of soil and its horizons. While the general term bioturbation refers mainly to these three mixing processes, unless otherwise specified it is commonly used as a synonym to faunalturbation (animal burrowings).[1][2][3][4]

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Beginning with Darwin, the earthworm has been recognized as a key bioturbator of soil biomantles and human artifacts on many continents and islands.[27][28][29][30][31][32]
 
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acespicoli

Well-known member

Oxidation​


A pyrite cube has dissolved away from host rock, leaving gold particles behind
.
Oxidized pyrite cubes
Within the weathering environment, chemical oxidation of a variety of metals occurs. The most commonly observed is the oxidation of Fe2+ (iron) by oxygen and water to form Fe3+ oxides and hydroxides such as goethite, limonite, and hematite. This gives the affected rocks a reddish-brown coloration on the surface which crumbles easily and weakens the rock. Many other metallic ores and minerals oxidize and hydrate to produce colored deposits, as does sulfur during the weathering of sulfide minerals such as chalcopyrites or CuFeS2 oxidizing to copper hydroxide and iron oxides.[36]

Hydration​

Mineral hydration is a form of chemical weathering that involves the rigid attachment of water molecules or H+ and OH- ions to the atoms and molecules of a mineral. No significant dissolution takes place. For example, iron oxides are converted to iron hydroxides and the hydration of anhydrite forms gypsum.[37]

Bulk hydration of minerals is secondary in importance to dissolution, hydrolysis, and oxidation,[36] but hydration of the crystal surface is the crucial first step in hydrolysis. A fresh surface of a mineral crystal exposes ions whose electrical charge attracts water molecules. Some of these molecules break into H+ that bonds to exposed anions (usually oxygen) and OH- that bonds to exposed cations. This further disrupts the surface, making it susceptible to various hydrolysis reactions. Additional protons replace cations exposed on the surface, freeing the cations as solutes. As cations are removed, silicon-oxygen and silicon-aluminium bonds become more susceptible to hydrolysis, freeing silicic acid and aluminium hydroxides to be leached away or to form clay minerals.[32][38] Laboratory experiments show that weathering of feldspar crystals begins at dislocations or other defects on the surface of the crystal, and that the weathering layer is only a few atoms thick. Diffusion within the mineral grain does not appear to be significant.[39]


A freshly broken rock shows differential chemical weathering (probably mostly oxidation) progressing inward. This piece of sandstone was found in glacial drift near Angelica, New York.

Biological​

Mineral weathering can also be initiated or accelerated by soil microorganisms. Soil organisms make up about 10 mg/cm3 of typical soils, and laboratory experiments have demonstrated that albite and muscovite weather twice as fast in live versus sterile soil. Lichens on rocks are among the most effective biological agents of chemical weathering.[33] For example, an experimental study on hornblende granite in New Jersey, US, demonstrated a 3x – 4x increase in weathering rate under lichen covered surfaces compared to recently exposed bare rock surfaces.[40]


Biological weathering of basalt by lichen, La Palma
The most common forms of biological weathering result from the release of chelating compounds (such as certain organic acids and siderophores) and of carbon dioxide and organic acids by plants. Roots can build up the carbon dioxide level to 30% of all soil gases, aided by adsorption of CO2 on clay minerals and the very slow diffusion rate of CO2 out of the soil.[41] The CO2 and organic acids help break down aluminium- and iron-containing compounds in the soils beneath them. Roots have a negative electrical charge balanced by protons in the soil next to the roots, and these can be exchanged for essential nutrient cations such as potassium.[42] Decaying remains of dead plants in soil may form organic acids which, when dissolved in water, cause chemical weathering.[43] Chelating compounds, mostly low molecular weight organic acids, are capable of removing metal ions from bare rock surfaces, with aluminium and silicon being particularly susceptible.[44] The ability to break down bare rock allows lichens to be among the first colonizers of dry land.[45] The accumulation of chelating compounds can easily affect surrounding rocks and soils, and may lead to podsolisation of soils.[46][47]

The symbiotic mycorrhizal fungi associated with tree root systems can release inorganic nutrients from minerals such as apatite or biotite and transfer these nutrients to the trees, thus contributing to tree nutrition.[48] It was also recently evidenced that bacterial communities can impact mineral stability leading to the release of inorganic nutrients.[49] A large range of bacterial strains or communities from diverse genera have been reported to be able to colonize mineral surfaces or to weather minerals, and for some of them a plant growth promoting effect has been demonstrated.[50] The demonstrated or hypothesised mechanisms used by bacteria to weather minerals include several oxidoreduction and dissolution reactions as well as the production of weathering agents, such as protons, organic acids and chelating molecules.
 
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