THE EFFECT OF USING COPPER FOR MITIGATING HISTOSOL SUBSIDENCE ON

Publisher Website
Google Scholar
Abstract
As a sequel to earlier studies on the suitability of using moderate and nonbiocidial amounts of Cu for slowing down the undesirably fast degradation and resultant subsidence of cultivated organic soils, this greenhouse investigation showed that the yield, Cu status, and nutrition of minicarrots, carrots and onions grown in an organic soil (B) containing 1060 ppm (wt/wt) Cu were similar to those grown in an organic soil (A) containing 136 ppm Cu. The long-term investigation also simulated a situation where B, containing about 3 times the Cu required for mitigating the subsidence by about 50%, is mixed with a mineral sublayer in 1:1 vol/vol proportion for agronomic convenience. Organic soil B so mixed individually with sand, shell-rich deposit (soil S), gyttja (soil G), or a clay (soil Cl) sublayer thus produced soils B1, S1, G1 and Cl1, respectively. Minicarrots, carrots, and onions grown in these 4 mixtures also apparently were not adversely affected by the Cu added to them by soil B. Soils S2, G2 and Cl2, obtained by amending soils S, G and Cl, respectively, contained Cu in excess of the equivalent of 5% of their cation exchange capacity. As in previous studies, the Cu in these soils tended to affect adversely the yields or Cu status or nutrition of minicarrots, carrots and onions grown in them. However, the severity of the adverse effects apparently declined with time.
Keywords