Soils exam 2

7 micronutrients

Iron, Chlorine, Manganese, Boron, Zinc, Copper, Molybdenum

Macro 1

Nitrogen, N, elemental, low OM, leeching, yellow leaves

Macro 2

Phosphorus, P, p2o5, root health, low or high ph

Macro 3

Potassium, K, K2o, stomata opening, coarse texture, wilting and stunting

Macro 4

Calcium, Ca, Ca2+, cell wall formation, acidic soil, slow growth

Macro 5

Magnesium, Mg, Mg2, enzyme activation, high ph, streaked yellowing of leaves

Macro 6

Sulphur, S, So42, phytochemicals for defense, low in OM, spindly plants

Salinity

Measured by EC, improved by leaching or removing soil

Sodicity

Measured by SAR, ph 8.5 or more, replace soil or add gypsum

Two ways nutrients are added to the soil

Decomposing OM, nitrogen fixing bacteria and fungi

Two ways nutrients are removed from soil

Immobilization, leaching

Nitrification

Plants taking ammonium, converting to No2 (nitrite) then to No3 (nitrate)

Denitrification

Nitrate reduced to N gas by anaerobic bacteria

Immobilization

Biota consume the OM, holding the nutrients in their bodies until the poop and/or die

Mineralization

Organisms break down organic forms into simpler molecules, releasing ammonia, which is converted to ammonium (Nh4)

Natural fertilizer for N

Blood meal, pro- uses byproduct that would be otherwise wasted, slow ish release, con- too much can burn your plants, too much N can leach

Natural fertilizer for P

Rock phosphate, pro- can raise ph in acidic soils, othertrace minerals, con- mining, expensive in small amounts

Natural fertilizer for K

Liquid kelp, pro- other minerals and hormones, can be made at home, cons- takes time to make, not always allowed to collect kelp from beach