People in Niger are being urged to curb their use of firewood at next week's Eid al-Adha Muslim festival.

It is an occasion when families often sacrifice sheep before roasting and eating them.

The capital, Niamey, is expected to burn around a fifth of the amount of the wood normally used in a whole year.

The chopping of trees is linked to desertification, which in recent decades has had a drastic impact on Niger.

During Eid, known locally as "Tabaski", the authorities in Niger expect close to 400,000 sheep to be sacrificed in Niamey alone.

To roast them, almost 50,000 tonnes of firewood will be used.

What is Eid al-Adha?

• Eid al-Adha is a public holiday in Muslim countries
• During festivities, Muslims all over the world who can afford it sacrifice a sheep - sometimes a goat - as a reminder of Ibrahim's obedience to Allah
• According to the Muslim, Christian and Jewish faiths, God appeared to Ibrahim (Abraham) in a dream and asked him to sacrifice his son Ishaq (Isaac) as an act of obedience
• The devil is said to have tempted Ibrahim by saying he should disobey God and spare his son
• As Ibrahim was about to kill his son, God stopped him and gave him a lamb to sacrifice instead
• Families share out the meat among family, friends and the poor, who each get a third
• Eid usually starts with Muslims going to the mosque for prayers, dressed in their best clothes, and thanking Allah for all the blessings they have received
• It is also a time when they visit family and friends as well as offering presents
• At Eid, it is obligatory to give a set amount of money to charity to be used to help poor people buy new clothes and food so they too can celebrate

'Use coal instead'

The head of Niamey's environment agency, Col Oumarou Alou, called on people to use coal instead and said officials would be stopping trucks, donkeys and camels to prevent excessive loads of wood being brought into the capital.

"We are looking for ways to reduce consumption [and] have developed other means of conducting heat, by using metal equipment as well as coal," he told BBC Afrique.

"We are trying to get the message across to various groups that could sway opinion, so that we can preserve our forests."

Niger, one of the world's poorest countries, is situated on the edge of the Sahara.