Think of any great modern city, and you’ll likely find a river in its proximity. London has the River Thames, Varanasi has the Ganges, Shanghai has the Yangtze, Vietnam has the Mekong. The list is inexhaustible.
Rivers have been indispensable for humanity. In ancient times, a river provided access to water for consumption, livestock and agricultural purposes. In modern times, being close to a river also offers a means of transport and energy, and may even boost economic and cultural value, and tourism.
Kallang River, Singapore (Source: Mark Stoop/Unsplash)
Strip away the benefits a river provides to humans, and therein lies a complex system critical for biodiversity and intrinsically linked to our climate. Freshwater ecosystems are home to thousands of species of plants, fish, insects and other fauna, and rivers play a crucial part in the water cycle which regulates rainfalls and other climate-related phenomena.
But rivers around the world are facing many threats, including natural hazards, human activities, and climate change.
Rivers in the tropics are strongly impacted by human activities, such as urbanisation and construction, which accommodate the fast-growing populations in these regions. They are also impacted by natural hazards such as tropical cyclones, droughts, and floods, which are exacerbated by climate change. Collectively, these factors affect the quality and availability of water.
At the Earth Observatory of Singapore (EOS), the Tropical Rivers Group aims to understand how rivers in the tropics respond to human activities and natural hazards.
The Tropical Rivers Group is led by Assistant Professor Edward Park, a Principal Investigator at EOS who started his career in North America studying the Amazon River. After several years studying the Amazon, a relatively pristine river basin with limited human impacts, he moved to Singapore to study river systems in the tropics which are facing complex challenges due to human activities and natural hazards.
Acoustic Doppler current profiler deployment by Asst Prof Park and Research Associate Yuen Kai Wan from the Tropical Rivers Group (Source: Tropical Rivers Group/Earth Observatory of Singapore)
Asst Prof Park recently spoke to Channel NewsAsia about Vietnam’s water security. He shares how the health of both the Mekong River and the Red River are under threat from various factors, including climate change, dam construction, and pollution. Changes to the river water quantity and quality could affect the agricultural sector as well as the industrial sector that requires a significant volume of water, such as electronics and food processing. He foresees more pressure on water resources as major Vietnamese cities continue to expand, which increases the demand for water consumption and can strain waste-water management infrastructure.
Mekong River at dusk (Source: Tropical Rivers Group/Earth Observatory of Singapore)
To better understand how the tropical river systems are changing, the Tropical Rivers Group use various techniques, including remote sensing, field surveys and numerical modelling. By combining these different techniques, they aim to gain a more holistic understanding of river systems and how they interact with their surrounding environment. For instance, under a project funded by the Ministry of Education of Singapore, the group is working towards understanding riverbed sand mining rates to facilitate sustainable sand harvesting across the rivers in Southeast Asia.
Tropical Rivers Group collecting bathymetry data (Source: Tropical Rivers Group/Earth Observatory of Singapore)
The Tropical Rivers Group’s work is critical to promoting sustainable river management so that society can continue to benefit from resources provided by the river in the long-term, while minimising environmental impacts.