Africa's most populous country, Nigeria, is in the middle of an election campaign. Presidential candidates have focused on the many problems that urgently need to be addressed.

They all agree on the importance of creating jobs, fighting corruption and improving security.

According to the United Nations refugee agency,UNHCR, around 3.1 million Nigerians are displaced, often due to attacks by insurgent groups and armed gangs.

Sarah Alabi, a supporter of Labour Party candidate Peter Obi, was very clear on what matters to her.

"My hope? For Nigeria to be a peaceful country," she said.

Flooding, desertification and erosion threaten the country

Last year, however, severe flooding killed more than 600 people and displaced hundreds of thousands. It has become obvious that Nigeria is facing another challenge that affects the entire country: climate change.

Across the country, people are seeing either too much or too little rain. While the surface area of Lake Chad continues to shrink, robbing fishers of their livelihood, the Atlantic Ocean is eating into the country's coast in the south.

The sea has even swallowed entire streets in Lagos, Nigeria's bustling commercial capital. Sarah Alabi had another take on the issue. She said Nigerians believe the climate will indeed change if Obi wins. "Then things will work out," she added.

Oil and gas: Important revenue source, or a threat?

But on the campaign trial, the presidential candidates have not discussed climate change and its devastating consequences. Obi, for example, is betting on fossil fuels.

"We'll create an environment that will spark investment in our oil and gas sector. Nobody will steal our oil again," he said on the campaign trail. "Our gas should be developed where it will give us more money than our oil."

Together with Angola and Algeria, Nigeria is one of Africa's largest oil exporters. Crude oil production averages about 1.2 million barrels per day. In some years, oil revenues accounted for more than half of the national budget.

The consequences can be seen in the Niger Delta in the southeast, where oil slicks stretch across the water. In some places, the shore is pitch black. Neither fishermen nor farmers can work there.

Nnimmo Bassey, a laureate of the 2010 Alternative Nobel Prize, is critical of Nigeria's oil production industry, which began in 1958.

"We still have gas flaring releasing millions of tons of carbon into the atmosphere, polluting the environment, causing biodiversity loss, displacement of communities and so many more problems, including deforestation and coastal erosion," said the environmental activist.

'Policy makers don't seem to understand'

At the beginning of February, several environmental protection organizations tried to find out how the candidates position themselves on climate change.

Of the 18 presidential hopefuls, only four agreed to take part in a panel discussion in the capital, Abuja. Although Bassey admitted that they did somewhat grasp the subject, his conclusion was sobering. 

"The environment has turned into a critical problem in Nigeria. But unfortunately, policy makers don't seem to understand that. Or they just think that there is nothing to be done about it," said Bassey.

In Gwagwalada, about 50 kilometers (31 miles) from Abuja, climate activist Adenike Oladosu was setting up her first office. The founder of the 'I Lead Climate Action Initiative' shared Bassey's assessment that environmental protection and climate change are not an issue in the election campaign.

Oladosu said a lot of education was needed to put due pressure on politicians.

Two years ago, when flooding destroyed a bridge between Lokoja in south-central Nigeria and Kaduna in the north, she pointed out, "people weren't talking about the environment, they were talking about the spiritual dimension and the casualties."

Oladosu is calling for a bigger debate on climate change and better information on the subject.

Africa must pay more attention to climate change: activists

In addition to her work in villages around the capital, Oladosu was also trying to call attention to the Lake Chad crisis, where the lake's surface has been shrinking for decades. As is the case in the Niger Delta, fishers and farmers are losing their livelihoods.

Increasing attention is being paid to the fact that insurgent groups such as Islamic State in West Africa Province are profiting from the situation by recruiting young men who have lost all prospects.

Oladosu insists that more attention needs to be paid to Lake Chad in particular, and funding be increased.

"This is a lake that affects not only Nigeria, but also Niger, Chad and Cameroon. If we just pay lip service to it, the crisis will not go away. According to a UN report it will get worse," Oladosu said.

When she noticed that Nigerian politicians were not taking up the issues, she decided to act herself.

"We need political leadership to raise awareness," she said, adding that she saw Nigeria at a crossroads. Saturday's election will determine whether climate action will move forward, or if the situation will only worsen, she said.

This article was originally published in German.