Effect of black carbon on the growth, development and evapotranspiration of maize

摘要

The effect of soot on certain parameters of maize was analysed. We applied low rates of soot (3 gm–2week–1) with a motorised sprayer. The effect of soot on evapotranspiration was tested on plants grown in evapotranspirometer (ET). Soot pollution had no influence on maize growth and development. Leaf withering after full maturity, ho wever, was delayed by the presence of soot. The ability o f soot to absorb irradiation and thus increase leaf surface temperatures led to an increase of 4% in the annual evapotranspiration sum. Soot pollution reduced dry matter (DM) on the rainfed plots (8.8 %), but not in the ET tanks. In the ET tanks, soot had no significant influence on either the stalk or the grain DM, though slight reductions were recorded. On the non-irrigated plot there was 12.4 % reduction in grain dry matter in response to pollution. Supplementary water supplies mitigated the plant damage caused by soot. A further advantage was detected in the number of deformed ears