In Victoria (The southish bit of Australia- for the Americans) they have vast deposits of "Brown Coal" or Lignite. They often complain about it because it is full of water and produces lots of greenhouse gasses to burn
(In the driest, inhabited continent, we complain of something being wet-I don't get it!)
But it seems to me this stuff is somewhere between black coal and peat on the evolutionary scale.
Could it be used like charcoal in the garden/farm?
Chemists, soil scientists I need some help here.
This is the only reference to it's use in soil I could find
Improving Soil with Coal-Derived Materials
Acidification of soil is a naturally occurring process.
However, factors such as excessive use of nitrogen fertilisers and overharvesting can accelerate its progress.
Acidification leads to increased solubility and availability of phytotoxic metals such as aluminium andmanganese, and the loss of nutrients such as phosphorus and calcium.
This can have devastating economic and environmental implications.
An estimated 90 million hectares of Australian agricultural land are currently classified as being acidic (pHCa < 6.5). Major trouble spots include the Western Australian wheat belt and significant sections of northern and
Previous research has shown that organic materials high
in oxygen functional groups (e.g. carboxylates and phenols)
can improve acidic soils. These functional groups, which may
be characterised by titrimetric or spectroscopic methods, can
act as ion exchange sites useful for pH buffering in soil,
nutrient transport to plants and the binding of phytotoxic metals such as aluminium, rendering them harmless to plants.
‘K humate’ (potassium humate) from brown coal is one such
organic material abundant in oxygen functional groups.
This project trialled a commercial humic product sold as a soil
conditioner in order to characterise, quantify and maximize its
effect on acidic soils. Experiments were conducted in which a
calcium additive was incorporated into the K Humate.
The calcium source was ‘Calsulmag’, a commercially treated coal
fly ash which contains inorganic additives such as calcium and
magnesium which are beneficial to soil.
These two products were trialled on two acidic soils – a
sandy soil used for pasture, and a clay loam vineyard soil.
The pasture soil was investigated in controlled soil column
leaching experiments where columns packed with soil were
treated on the surface with various amounts of amendments,
and then leached with water to simulate rainfall. After a
period of leaching, the soil was analysed down to 15 cm in the
profile for chemical parameters pertinent to soil fertility such
as pH and aluminium levels. The vineyard soil was
investigated in a field experiment where plots were treated
with various coal-derived amendments, and the chemistry of
the profile (down to 25 cm) of each plot was monitored at
regular intervals over about a year.
The findings of both studies were that in many cases K
Humate in conjunction with a calcium source such as fly ash,
increased pH, decreased aluminium levels, and increased
calcium and plant-available phosphorus levels down to
substantial depths into the soil profile (at least 6 cm). For one
of the soils, which is prone to waterlogging, the addition of K
Humate improved water retention and the permeability of soil
Results have been successfully presented at national and
international conferences and have led to new projects including: a
follow-up study of the vineyard field trial focussing on effects of
humates and fulvates (ex brown coal) on microbial activity,
aggregate stability and water-retention capacity of soil;
investigations of the use of organic amendments from various
sources (e.g. compost, municipal waste, etc) on the levels of
phosphorus in soil; alleviation of salinity in soils again using
various organic amendments; and the characterisation of an acidic
high organic carbon soil. These projects involving green products
have the support and expertise of local and overseas collaborators
from both private and government sectors.
Jason Issa (PhD Student) - April 2002
Not -too fond of coal fly ash- as I am told that it contains uranium and thorium (at least black coal does).
Though, I suppose,with a bit of radioactive glow, I could then garden in the dark.