* Fulani anger spreads jihad to central and southern Mali
* Climate change drying up Niger, exacerbating conflict
* Risk of revolt spreading to other countries
By Tim Cocks
MOPTI, Mali, Nov 20 (Reuters) - For centuries, Fulani cattle herders and the farmers of central Mali -- both dependent on the Niger River for precious water -- have had a deal.
The Fulani graze their cows on the greenery that springs up after the river recedes from its flood plains. As it gets munched the farmers plant their crops, now fertilised by cow dung, so long as they do not block access to the nomads' routes.
But as climate change shrinks the river, population growth swells its users and more land gets cultivated, the Fulani are being pushed deeper into poverty. Conflicts with their sedentary neighbours are growing.
Throw in radical Islam, abusive security forces, a feeling of political exclusion and a flood of guns from lawless deserts to the north, and conditions are ripe for a rebellion that could destabilise not just Mali but much of West Africa.
"The Fulani feel marginalised everywhere. In Mali, in Guinea, in Central Africa," said Abdoul Aziz Diallo, who runs Tabital Pulaaku, a Fulani association spanning 15 countries.
"In Mali, they're being infiltrated by the jihadists from the north and there is a very real danger from new Fulani militias that have emerged and are stoking inter-ethnic strife."
The road west out of Mopti, a city of muddy streets and a grand clay mosque on the Niger's banks in central Mali, crosses flooded rice fields and land where cows graze on wild grass.
Fulani herdsmen in robes and straw hats negotiate livestock sales with Bambara farmers. In May, however, armed Bambara and Fulani groups clashed in Tenenkou, west Mopti, and about 20 people were killed.
Such clashes are frequent and might be brushed off as local incidents. But Islamist militants are exploiting Fulani anger to spread jihad from the thinly populated north to its centre.
"The Fulani complained that farmers took all the land," said Lala Walet, a Mopti NGO worker promoting livestock commerce.
"So the jihadists came and said 'OK, join our group and we will help you fight to get it back'."
Jihadists have beheaded or slit the throat of scores of local officials in central and south Mali in the past year. In August 2015, 13 people were killed in a siege of the Byblos Hotel in Sevare, a town separated from Mopti by a tangle of creeks.
In July, gunmen killed 17 Malian soldiers in an attack on an army base in the town of Nampala, claimed both by northern jihadists Ansar Dine and a new Fulani militia, the National Alliance to Safeguard the Peuhl Identity and Restore Justice.
The latter said on Saturday it would lay down arms and rejoin a government peace process - one that has so far failed to quell the violence in the much more unstable north.
Bringing the Fulani into the peace process will be essential to prevent further such attacks, and if efforts to woo youths away from jihad are to have any hope of succeeding.
A 2012 Tuareg revolt in northern Mali was hijacked by Islamists, prompting former colonial master France to intervene to push them back.
The French action prevented the possible takeover of the capital Bamako by Islamists, a prospect that alarmed Western governments trying to push back the global spread of radical militancy.
The subsequent peace deal focused on soothing Tuareg grievances even though many Islamists were Fulanis.
That was a mistake, said Mohamed Attayoub, head of the political wing of Ganda-Iso, a Fulani vigilante group.
"We participated in the talks, but when it came to the deal, we were excluded from every organ of the state," he said.
Security Minister Colonel Salif Traore denied this, telling Reuters that everyone was able to participate.
Ali Nouhoum Diallo, an ex-head of both Mali's parliament and the regional bloc ECOWAS, in September created a nationwide vigilante group to help Fulani defend themselves.
He said security forces were harassing herders and arresting youths for simply reading the Koran outside.
Sitting in his Bamako house, Nouhoum Diallo dismissed the suggestion the Fulanis would rebel for an ethnic homeland, as the Tuaregs did.
"It is impossible for the Fulani to claim independence, because we are spread out everywhere," he said.
It was the failure of the state to protect them that was banding them together, he said.
Security Minister Traore denied organised repression of the Fulani but he admitted profiling may happen.
"We cannot stigmatise people of certain ethnic groups for something they haven't done," he said.
Still, the crackdown has deepened mistrust and a sense of persecution.
Millennia of wandering has left 20 million Fulani scattered across 20 nations, from Senegal's west coast to as far east as Eritrea. Many feel sidelined in Africa's modern states.
The sense of exclusion and the shift in the Islamist battlefield southwards to Mali's more populated, richer areas is a headache for President Ibrahim Boubacar Keita.
That was highlighted in November 2015, when gunmen killed dozens at the Radisson Blu hotel in Bamako.
Several Islamist groups claimed the raid but the government gave most credence to the Mopti-based Macina Liberation Front (MLF), a Fulani jihadist group allied to Ansar Dine.
The MLF's figurehead, Amadou Koufa, is a fiery cleric whose sermons call on Fulanis to rebuild historic empires like Massina, which once stretched over the Mopti region.
Hamma Cisse, an imam who was at the same Koranic school as Koufa, remembers a quarrelsome boy who wrote love songs and became bitter and disillusioned.
"The Fulani felt frustrated," he said. "The pupils in the French schools were considered superior, they always got the jobs. Amadou felt it as a real injustice."
Koufa moved to Mauritania and came back preaching radical Islam.
"He preached everywhere, village by village," Cisse said. "He was standing up for the Fulani, against poverty, against abuses by the water and forest authorities. One thing I'm sure of - people aren't following him out of religious conviction." (Additional reporting by Adama Diarra; Editing by Angus MacSwan)