Seven wetlands in East under Environment Protected Areas

By Dhaneshi Yatawara

The Central Environment Authority(CEA) recently concluded a research on wetlands in the Eastern Province to detect changes taking place in the wetlands in the recent past on par with various development activities that have been initiated. After studying 42 wetlands, CEA officials have identified seven wetlands in the East to be declared as Environment Protected Areas.

One of the wetlands

Ajith Gunawardena

"This was a conclusion made after an extensive study in 42 wetlands and when wetlands are declared as Environment Protected Areas it imposes restrictions on conducting development activities and other anthropogenic activities," said Ajith Gunawardena, Assistant Director of the Research and Development unit of the CEA.

The East has a significant issue in connection with wetlands. Since the Eastern Province is a heavily flood affected area, conserving the existing wetlands is hugely beneficial. The objective of this project is identification, mapping and change detection of important wetlands in the South Eastern River basins of Sri Lanka using satellite data. Locating prospective areas in the Eastern Province was the first step. This project marks the base line tool for the declaration of environmental protection areas under the National Environmental Act.

In this research around 18 biophysical parameters were used to evaluate every wetland and statistical analysis was conducted to prioritise the wetlands. The CEA initiated the project on Mapping and Change Detection of Wetlands in South-Eastern River Basin Region in Sri Lanka with the technical support and guidance from the Japan Aerospace Exploration Agency (JAXA), University of Tokyo and Geo-informatics Centre of the Asian Institute of Technology, Thailand under the theme Space Application for Environment (SAFE).

Wetlands play an important role in maintaining a healthy environment for human habitation. Under the RAMSAR convention six wetlands in Sri Lanka are recognised as Wetlands of International Importance, with a surface area of 198,172 hectares.

A wetland is generally an area which has soil that is saturated (filled) with moisture, such as a swamp or marsh. Until quite recently, the importance of wetlands was not identified in Sri Lanka. Most of the time, they were drained and used as construction space and for garbage dumps. Thto the entire eco-system.

Technical support and guidance from the Japan Aerospace Exploration Agency (JAXA)

In addition, these perform a range of functions which are extremely important.

Where uses are concerned, wetlands become useful in applications related to water supply, medicinal herbs, salt, agriculture and tourism. Important herbs such as 'Lunuwarana' and 'Neeramulliya' are taken from marshes.

Marshes play a vital role in the mitigation (reducing) of floods, purification of water and as a carbon sink where carbon dioxide is accumulated. Specifically in the Eastern Province where floods have a greater negative impact on the communities, economically and socially flood mitigation is a key factor for the development of the area.

Wetlands are also considered the most biologically diverse of all ecosystems, serving as home to a wide range of plant and animal life. The biodiversity of wetlands, which supports a range of animal and plant species, is very significant. For example, among the total inland species with backbones in Sri Lanka, about 30 per cent are ecologically dependent on wetlands. Among the migratory birds that visit Sri Lanka annually, more than 50 per cent are directly dependent on wetlands for food and shelter. Among the threatened ecosystems of Sri Lanka, wetlands take high priority. A majority of the wetlands in Sri Lanka are facing various threats due to harmful human activities such as encroachment, habitat deterioration and degradation, pollution, direct loss and exploitation of species, spread of invasive alien species and destruction due to natural phenomena.

The UN Millennium Ecosystem Assessment determined that environmental degradation is more prominent within wetland systems than any other ecosystem on Earth. International conservation efforts are being used in conjunction with the development of rapid assessment tools to inform people about wetland issues.

Carbon is the major nutrient cycled within the wetlands. Most nutrients, such as sulfur, phosphorus, carbon, and nitrogen are found within the soil of wetlands. Anaerobic and aerobic respiration in the soil influences the nutrient cycling of carbon, hydrogen, oxygen, and nitrogen and the solubility of phosphorus thus contributing to the chemical variations in its water. A wetland system needs to be monitored over time to in order to assess whether it is functioning at an ecologically sustainable level or whether it is becoming degraded. Degraded wetlands will suffer a loss in water quality, a high number of threatened and endangered species, and poor soil conditions.

Due to the large size of wetlands, mapping is an effective tool to monitor wetlands. There are many remote sensing methods that can be used to map wetlands. Remote-sensing technology permits the acquisition of timely digital data on a repetitive basis. This repeat coverage allows wetlands, as well as the adjacent land-cover and land-use types, to be monitored seasonally and/or annually. Using digital data provides a standardized data-collection procedure and an opportunity for data integration within a geographic information system.

"Threats to wetlands are specific to each site. Yet we identified that garbage dumping poses the greatest threat to many wetlands," Gunawardana added. Specifically to East it is crucial to keep the lagoons, marshes and all the wetlands as it is to control the floods that occurs with every rainy season and avoid disasters, said Gunawardana.