Scientists involved in the Terra project say that sorghum could fit the bill – because it has relatively high energy potential without demanding too much in the way of fertiliser, land or soil.
The conclusion is that agriculture with manure, fertilisers, moderate soil cultivation and varying crops, in general, is favourable for earthworms, except for certain species.
Indeed, it can be strongly argued on scientific grounds that the most environmentally friendly action that Ghanaian farmers could now take is to increase the use of fertiliser, since soil fertility is declining at an alarming rate.
A second mechanism, which has the same effect as the first, is the increasing addition of nitrogen-rich fertilisers to soils by agriculture and forest managers.
Total C and N in fertiliser granules, soils and plant tissues were measured using a high-frequency induction furnace (LECO Pty Ltd).
Following a brief overview of the reactions of Cd and common P compounds that are used as fertiliser in soils, the review focuses on the above mentioned mechanisms for the (im mobilisation of Cd by P compounds in paddy soils.
Compared to pastures that receive adequate P fertilisers to maintain soil P concentrations, applying half maintenance rates, or no P, slowly decreases soil P concentration and P losses to water.
In many of these fields, soil, fertilisers and pesticides are sloshing away with the water.
Organic farming does not use artificial chemical fertilisers, instead building soil fertility through crop rotations and particularly the use of clover that fixes nitrogen naturally from the atmosphere using the sun's energy.
It is of growing concern, however, that many developed countries are now so focused on turning waste bio-matter into biofuel that farmers are having to spend more on inorganic fertilisers to improve soil condition.
