User:KVDP/Soil substrates and fertility   

KVDP's notes This article lists the notes KVDP made on the subchapters 1 to 5 of the Agriculture manual. The information presented here needs to be reworked, completed and inserted to the appropriate articles.

Contents 1 Subchapter 1 1.1 Organic substrates 1.2 Inert substrates 2 Subchapter 2 3 Subchapter 4

[edit] Subchapter 1

Part of the soil which is effectiverly used by the plant -->2m (for trees) Soil improvement needs to be done for the upper 25-30cm of the soil Consolidaded soil= infertile

[edit] Organic substrates

• Potgrond (english ?)= mixture of black & white Bog
• Peat

[edit] Inert substrates

• rock wool (vulcanic origin)
• polyurethaan
• pumice

The buffer-capacity of organic substrates is much higher than of inert substrates.

Texture: sizes of the grains of the soil structure: the whole of the grain sizes + pores

Determination of the dominating ground particles is done using a sieve (soil sieve) Sand, loam, clay --> do not describe the types of the used stones, only describe the sizes of the soil grains (texture)

Less nitrate problems are present with heavier soils (eg soils with more clay, ...)

clay soils: add lime to coagulate (crumb structure) sand soils: add organic substances/humus

Do not cultivate with rainy weather, and do not cultivate heavily with dry weather (eg hoeing )

organic material becomes humus (stabile) after humification Humification is done mostly using bacteria; Humus is gone after 2,5 years; having transformed into mineral substances. The degradation of humus is done more quickly with sand soils.

Humification depends on:

• temperature (below 4°C, soil life comes to a halt)
• water
• air
• nitrogen -->C/N ratio has to be smaller than 30

material	C/N-ratio
sawdust	400
horse manure	30
grass	10-20

Note: too nitrogenous soils can be benefitted by a large quantity of carbon (eg sawdust)

Failed to parse (PNG conversion failed; check for correct installation of latex and dvipng (or dvips + gs + convert)): QuantityOfCarbon_X_1,72=humusquantity in the soil

more humus -->soil gets a more darker color, contains water better, more soil life

Material	Carbon quantity	Humus
Sand	2,3%	2,3_X_1,72=?
Sand-loam	1,4%	1,4_X_1,72=?
Loam	1,4%	1,4_X_1,72=?
Clay	2,1%	2,1_X_1,72=?

Too much humus -->generates too much nitrogen/nitrate

evaporation= soil that evaporates water transpiration= plant that evaporates water

sea climate= unstable concerning surface soil water table (1m variability)

When all soil untill the capillary water zone/saturated zone is poached, it needs to be left alone for years untill the ground water can once again rise up to the surface via the pores.

hydrometer= measures the quantity of water that needs to be added

PH 0 (=acid), 7 (neutral), 14 (basic) 0-4: very high acidity, 4-5: highly acid, 5-6:medium acid, 6-7:weakly acid 7-8: weakly basic, 8:medium basic, 8-10: highly basic between 5-8 is thus acceptable the soil PH can shift by 0,5-1 according to the time of year

PH-H₂O (free hydrogen-ions) -->clay-humuscomplex -->current acidity/basicity PH-KCL: (free hydrogen-ions +clay-humuscomplex-ions) -->total acidity/basicity The difference between the 2 is the degree of exchange in acidity

ideal PH-values per soil type: sand: 5,4 PH loam: 7 PH

Depending on the crop to cultivate, more or less acid soil needs to be used

increasing/decreasing soil PH -->extensive task, requires several years

[edit] Subchapter 2

Fertilising is not equal to improving the soil Fertilising =adding organic, anorganic substances Improving the soil = adding organic, anorganic substances + improving the soil structure, PH, ...

A plant absorbs CO₂, H₂0, minerals (main elements: N, S, K, Ca, P, Mg,trace elements: Fe, Zn, Cu, Mn, Mo, B, other:Cl, Na, Si, Al)

Element	Forms of absorbing
N	No3- (nitrate), Na4+ (ammonium)
S	So42- (sulfate)
K	K+
Ca	Ca2+
Mg	Mg2+
P	H2PO3-

fosfates, sulfates, nitrates are thus the forms in which the elements are absorbed Fosfates and gelates are also used as agricultural fertiliser !

Especially N, P, K, Mg are added as fertiliser. The trace elements are usually present in sufficient quantities, but the soil is usually badly equipped to let the plant absorb the elements

No₃^-, Na₄⁺, So₄^{2-, K+, Ca2+, Mg2+, H₂PO₃-}

• in soil water (solution)
• clay-humus complex -->holds positively-charged elements, rain water can not flush these to greater depths
• mineral store
• organic store

Nitrogen (N)

• absorbed from nitrate No₃^- (immediate absorption), and ammonia Na₄⁺ (conversion takes 3-4 weeks to 2-3 months),
• absorbed from artifical fertiliser as lime nitrate (Ca(NO₃)₂), ammonium nitrate (NH₄NO₃, ammonium sulfate ((NH₄)₂, SO₄)

organic material causes more nitrogen problems

phosphor= directly absorbable by H₂PO₄^- (phosphate)

phosphor cycle

Potassium (K): Has a relation to nitrogen; even ratio N-K needs to be respected !

Too much potassium gives problems with magnesium

Potassium is stick to clay-humus complex

(Too much/little ?) Calcium: usually provides a problem with the watertransport inside the plant

Nitrogen	Products	Nutritional substances	Soil improvement
N-poor	Peat	none	improved
N-poor	green fertiliser	little	improved water capacity
N-poor	compost	little-medium	added humus
cow manure	N,P,K	soil structure improved
N-rich	chicken manure	N	little or none
N-rich	dried types of manure	N, P, K	very little

Compost pile:

• needs to be placed in the shade, during summer (countries with temperate climate)
• compost booster contains the required bacteria
• material needs to be used with a 20-30 C/N ratio
• do not use too large chunks
• moisturise the pile
• near the end of the compostation (when the temperature again begins to drop), it needs to be turned

N-P-K-Mg (12-10-18-5(2)) in percentage

0,6kg N/Are: 100kg ->12 kg (12%)

0,6kg X 100/12= 5 kg

Organic fertilisers: never exceed by more than 10% per element (expensive fertiliser if bought)

acid binding value (ABV) CaO -> Co(OH)₂ (calcium oxide) 1 ABV= 1kg of CaO/100kg lime Maximum= 5 ABV/Are/year

ASEF --> can be contacted for soil-analysis sets (belgium) personal mobile soil analysis tests --> are only capable of determining PH, ...

Generative	Vegetative
Very variable	Invariable
Seed	Plant parts (clones)
Self-pollinators: usually less seed-variable, cross-pollinators: more seed-variable
F1: first filial series, F2:second filial series

F1: first line after crossing A7 and B7 (parental lines or P1, P2, ...) F2: cross between 2 F1 plants

Stratifiying or layer stacking: some seeds require more than 1 year for stratification (hot-cold-hot period or cold-hot-cold); others only require a short germ resting time or none at all

sowing depth= 2 to 3 times the thickness of the seed; however sowing needs to be done deeper with dry weather (the deeper= the more moisture), and shallower with wet weather

Vegetative propogation Roots: by adventitious buds on the roots Root propagation: somewhat larger pieces of the root are cut into pieces, they are planted and left for some time (wound can then dry) and planted (this technique is mostly done with tuberous roots)

air layering: soil is put unto one-year old twigs (not with woody stems)

Bulbs: left to lie for a while until the bulbs become well visible

stem cuttings: only with very young twigs

Period:

• herbal cuttings (woody plants) : (for temperate climate countries) spring and early summer (may-june), remark: not strong, fragile, do root rapidly
• woody cuttings: late summer, fall (for non-decidious plants) or winter (for decidious plants)

types of cuttings: leaf bud cutting (eg with vitis vinfera, ...) or stem cutting (oblique cut above the bud for the top, traight at the bottom)

head stem cutting is not equal to a stem cutting

cutting with a heel: the heel contains more auxines, cauing it to root quicker

fungicide: will slow down the rooting at temperatures above 15-20°C

a too wet space to do the cutting in is also disadvantagous, plant pots also need to be placed off the ground to allow moisture to ooze out

note: stem cuttings can be cut trough slightly (upto the cambium) at the bottom on both ends to root more quickly

head stem cutting: top of the head needs to be cut off (decays quickly)

woody cuttings: old wood needs to be cut in winter and can be planted with the head slighly above the soil (eg raspberry)

grafting (in winter):

oculating (late summer, august-september); when the bark releases

success: when the stem becomes yellow and falls off

fungi: usually have a full lifecycle on the course of a few days Conditions: hot and moist Crop rotation is very important as a preventive approach to combat fungi

Botrytis: parasite that targets wounds, mostly saprofytic, note that wounds can also be cause by a heavy impact of rain (cellular damage)

Powdery_mildew occurs on dry, hot weather, the wooly fluff is everywhere, including the bottom of the leaf

Downy_mildew occurs with wet, hot weather

Weeds can be a host for fungi

the spraying of silicic acid increases the plant defenses scattering seaweed calcium increases the PH, leaves dry more easily cupper sulphate /cupper hydroxide /cupper oxide + Bordeaux mixture are other ecologic pesticides

the use of more resistant races is also advised old races are generally less disease resistant

bacteria are usually a secundairy corruption (eg after a fungi attack) or with wounds (weakened plants)

virusses -->direct contact, can not survive long without the host, several species, eg persistent -->remain in the host, also if transferred

healthy seed -->virus free remove leaves (with virus, mites, ...) from plants

young plants need to be seperated from the older ones, older plants are more prone to virusses, and will then transfer them

Eals:

Eals exist in 2 varieties: parisitic and saprofytic (good-type) eals Several eals (=nematodes): some live in the roots, near the roots, cyste-eals (latter can survive for 5-10 years in the soil)

Eals are the greatest cause of "soil fatigue"

Combating can be done using crop rotation, some eals are used against taxus beetle, ...

insects: usually also have antennas 2 types exist: with incomplete metamorphose (egg -nymphe-insect) with complete metamorphose (egg-larva-cocoon-nymph-insect) difference: nymphe looks like the insect larva does not look like the insect (eg butterfly)

mites:generate honeydew -->formation of fungi can occur hereon

dry weather: mite wet weather: fungi daily checkups need to be done for both

seaweed: fortifying nettle manure: pooring on the plant (fortifying) soap spiritus (brown +green soap+spiritus) natural predators: biological

Wireworms: mostly with tuberous crops Beetles: these usually disappear after a certain period of time

Insect trap

Every plant can be considered a weed weeds can cause pests

Preventing weeds

Field hygiene: weeds that are beginning to form seeds need to be destroyed. A possibility is throwing them with the chickens (these pick up the seeds and destroy any emerging plants of seeds that survived)

mulching: this closes off the soil, so the temperature is lower at night; more risk of nighttime frost (temperate climate countries). Retains more moisture, ... dough. Average thickness is 5-7cm of mulch.

False sowing bed: prepare the soil, remove weeds after 14 days, burn off, sow without disturbing the soil -->less weeds

Schoffel (english?) is not equal to a hoe

pregerming = imbibition; soak for 24 hours in water and then plant (do not leave to germ) wet kitchen paper is also a possibility

With irrigation the soil again reconsolidates

plants need to be planted at certain depths

sowing soil: mixture of compost/green fertiliser: often too wet, since it keeps too much moisture, add sand, dough watch the PH (other substances can be added to attain the correct balance again)

sowing trays

sowing soil: needs to be sieved first

scattered sowing: sow in rows if seed is too small to handle

[edit] Subchapter 4

Classical pest control

Biological pest control

Intergrated pest control

Soil cultivation: on the right time Biological pest control: only in greenhouses, constant temperature is required

Garlic: spraying against thrips: these then come to the surface, after which nettle manure can be used

Tropaeolum majus: signal crop for mites

Burying of green fertiliser: maximum 20 cm deep (with a 2cm thick layer)

Harrowing: the larger the seed; the larger the lumps of soil can be for the sowing, as the soil consolidation increases

After the sowing, slightly compress the soil (eg with the back of the