Time-series Analysis of Ground-level Ozone in Muda Irrigation Scheme Area (mada), Kedah

It has long been recognised that pollutant gases cause significant impacts on crops and studies conducted revealed that ground-level ozone is responsible for most of the crop-yield losses from air pollutants whereby losses from other pollutants are minimal, relative to ozone (Fuhrer et al., 1997; Pleijel et al., 1998; Ishii et al, 2004). Ozone is a secondary pollutant resulting from photochemical reaction of a variety of natural and anthropogenic precursors (mainly volatile organic compounds (VOCs) and oxides of nitrogen (NOx)). Despite massive and costly control efforts, countries in Europe and North America still experience severe ozone problems (Wu and Chan, 2001). People in Asia cannot escape from ozone pollution. In some large Asian cities, elevated ozone levels have been reported (Chan and Chan, 2000). Nevertheless, the long-term ozone trend, especially in Malaysia, is relatively less researched. TIME-SERIES ANALYSIS OF GROUND-LEVEL OZONE IN MUDA IRRIGATION SCHEME AREA (MADA), KEDAH.