SUMAPAZ, Colombia (Reuters) - Facing a lake covered by low-lying clouds, spiritual leader Arwa Viku burns leaves hoping that the smoke will carry his message, his voice mixing with the sound of waves lapping the grass-lined shore.

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Here in mountainous central Colombia, Viku’s Arhuaca Indian tribe is concerned that the country’s water supply is being threatened by an expanding unregulated agricultural sector.

They also worry about a four-decade-old guerrilla war in which leftist rebels plant landmines and military counterstrikes disrupt the ecosystem. Viku looks up at the smoke and prays for a restoration of the water supply.

The ritual is focused on this country’s “paramos”, or flat zones found on mountain ranges. The areas, located at heights over 9,800 feet, are filled with grass, shrubs and other vegetation that absorb water and feed Colombia’s rivers.

“More than half the planet has already been destroyed,” the mustachioed Viku says, his eyes peering out from under his traditional white conical hat.

“Our Mother earth has been violated and mistreated. So please help us to take care of what is left. Besides being good to us every day, the planet gives us warnings and makes more demands on us, because we’ve turned against it,” he added.

Colombia is known for its ample supplies of fresh water. But the war -- which began in the 1960s with the birth of the Revolutionary Armed Forces of Colombia, or FARC, rebel movement -- has combined with global warming to damage the environment.

The chemical-heavy process of making the cocaine that finances the FARC has also taken its toll on Colombia’s ecosystems. A U.S.-backed security campaign has pushed the guerrillas into remote rural areas, where violence, cocaine production and related environmental damage goes unchecked.

Viku and a handful of other Arhuaca members scratch stones together, sparking fire to burn dried leaves and send smoke from this paramo to others around the country where water supplies are at risk. They wear white pants and robes cinched at the waist by decorated belts.

“We sing to the water because it is alive, it hears, it has feelings. It is a living thing,” female tribe member Ati Quigua told Reuters. “We are drops from the same river, part of the same water cycle.”

The paramos are crucial to maintaining the Magdalena River, which, like the Mississippi in the United States, cuts through the heart of the country. They also feed the Orinoco River, which connects Colombia to neighboring Venezuela and Brazil.

State environmental official Emilio Rodriguez agrees that the situation in the paramos is “worrying”, considering that they are a key water source for capital city Bogota.

“A lot of the problems (confronting the paramos) are structural problems having to do with land care and colonizers who arrive in nearby areas, some of which are protected,” Rodriguez said.

Poor Colombians, some displaced by war, regularly arrive in national parks looking for fertile land to build subsistence farms, larger plantations and cattle ranches. These illegal operations go unregulated and can do extensive environmental damage.

“This area should be declared sacred territory, a water sanctuary,” Quigua said.