Climate change will disrupt balance of industry

•  Going back to basics is the way out

With climate change being a key concern among the community, Ratnapura Tea Research Institute Senior Research Officer Dr. M.A. Wijeratne noted that general tea cultivation would be disrupted in the coming years due to global warming.

Possible impacts

Discussing the potential impacts as predicted by scientists, Dr. Wijeratne explained that the biological needs of fauna or flora were largely governed by ambient temperatures. Generally the rising temperatures stimulate crop growth. However, temperature extremes can deliver negative impacts.

“Tea bushes prefer an ambient temperature in the range of 18-25 °C with the optimum being around 22°C. Therefore up country tea plantations with cooler climatic conditions, where ambient temperature that is below 22°C, could benefit from global warming.”

However this may affect growth and yield of tea at low elevations because the mean temperature is above the optimum range. “Nevertheless scientists are very positive about increasing CO2 concentration. It has a fertiliser effect.”

Looking at climate changing impact on other aspects of tea cultivation, he listed pest and disease outbreaks, weak competition, soil organic status and soil health, etc.

“With the climate changing, there could be a possibility of shifting regional specific pest diseases from one region to another. Scientists are predicting rising temperatures and rain fall extremes in a short period of time. This can reduce soil organic matter levels in our tea lands.”

TRI studies and analysis

TRI has collected a large amount of data and studied climate change impacts on some of the aspects, he said.

According to analysis and prediction of general circulation models for 2050, tea production at high elevations (up country) shows a positive trend with production increasing. However the projections are slightly negative for low country where temperatures are high even at present.

TRI could not assess a clear trend for tea production at mid elevations. “We were also unable to generate data regarding quality variations of tea and of impact on other aspects such as pest and disease infestation and soil. We need to closely look at those factors of tea cultivation in the future.”

He also noted that the Intergovernmental Group (IGG) on Tea and the Food and Agriculture Organization (FAO) has already formed a special working group to study the climate changing patterns and propose suitable adaptation methods to minimise adverse impacts.

Measures to mitigate impact

Speaking of adaptation measures to mitigate serious negative impacts due to climate change, Wijeratne stated that selection of land with very good soil conditions for future cultivation was one of the key strategies proposed by scientists.

The diversification of lands with marginal soils for other profitable uses such as fuel wood, energy plantations and planting of pest tolerant cultivars, etc., are also measures the industry should look at.

“It is important to properly establish and manage reduction of temperature around tea bushes. Soil conservation and improvement are a must. Application of green manure and compost is also essential.”

In areas where permanent water sources are available, irrigation will also help mitigate the impacts of climate change. To face any quality issues in time to come, industry stakeholders should maintain very good leaf standards and minimise post harvest damages in order to preserve the quality of Ceylon Tea.

“These strategies are no high tech approaches, but basic principles of agriculture. To survive climate change with little harm, we need to get back to basics,” he concluded.