Abstract:
A study to elucidate relationship between weather factors, tea productivity and
SouthernOscillation Index (SOl) was carried out covering all tea growing areas in Sri
Lankato understand the impact ofEI Nino effect on tea industry.
Nine Agromet and Meteorological stations were selected covering all tea growing
regions(High, Mid and Low) in Sri Lanka to collect rainfall and temperature data of a
period of 30 years (1970-99). Monthly tea production and tea land extend were
obtained from past records for the said 30 year period.
Linear correlation and time lag correlation between time series of SOl, Tea
productivity, temperature and rainfall was analyzed with SPSS and MSExcel
statistical packages. Results indicate that the tea productivity in high and mid tea
growing areas increased with the increasing temperature. In the case of low country
increasingtemperatures up to about 27-28 °c was found to be favorable for the tea
growth with increased productivity and further increased in temperature beyond 28
DC,would reduce the tea productivity. Tea productivity was also found to be
increased with increasing rainfall up to 100 mm and excess rainfall than this limit
shows no increase of tea productivity. Results conclude that there is a correlation
between SOl and temperature variables and that the El Nino effect has a negative
impact to decrease the tea productivity in the low country tea growing regions.
However,no clear relationship was found between El Nino and tea productivity in up
andmid country regions
