Litter fall and leaf decomposition in a sewage polluted mangrove stand at the Red Sea

الملخص EN

Liller fall in a sewage polluted mangrove stand of Avicennia marina at the South Corniche of Jeddah city was estimated to be 1.511 g dry wt m-2 day' .

Leaves were ubiquitous in litter fall through out the year with maximum values on April, May and June.

The reproductive pans were the main doners during reproductive season.

Flowers were initiated on September and fruits shot up to a high level of production on Decemberto April with a maximum production on January and February.

II overlapped with the maximum leaf letter production season on April.

This overlap resulted in an extended high total litter production, lasting for7 months.

followed by a shorter period of 5 months of relatively low production.

Such behaviour is unique to the study area and was not reponed even in the closest mangrovestands.

It was attributed to sewage pollution.

Leaf tiuer decomposition rate was also monitored.

The monitoring was on ground surface and subsurface in both summer and winter seasons.

The surface decay on summer was faster at the first 2 days.

The ultimate loss for both seasons was almost identical at the end of the experiment.

The subsurface decay rate for both seasons was fairly steady almost over the entire period though slightly faster rate in summer.