PARIS, SEPT. 13 -- The South Pacific island of New Caledonia voted overwhelmingly to remain a French territory today in a contested referendum that government critics said settles little and could lead to more ethnic violence.

The future of the 8,500-square-mile island has been a troublesome political issue in France since an insurrection in 1984 by the indigenous Melanesians, who have become a minority among thousands of European and other settlers prospering under French rule.

President Francois Mitterrand has expressed deep disagreement with Prime Minister Jacques Chirac's handling of the dispute, straining an uneasy working arrangement between the Socialist president and Chirac's neo-Gaullist government. In addition, Chirac's policy in New Caledonia has displeased New Zealand, Australia and other Pacific neighbors that see French rule as a colonial vestige out of step with the times.

French officials said 58.9 percent of the approximately 84,000 registered Caledonian voters cast ballots in the peaceful referendum. They were guarded by an 8,000-man security force, including paratroopers.

The turnout, which was about 8 percent higher than in elections in 1984 and 1985, repudiated an abstention campaign waged by Melanesian separatist leaders, government officials asserted.

Chirac, who returned here today from visiting French overseas departments in the Caribbean, said the New Caledonia balloting showed "triumphant participation" by the population. He called on all the island's political movements to "draw the conclusions of the uncontestable choice that has just been democratically expressed."

"I invite them to look toward a future of solidarity with confidence and lucidity," he added.

Bernard Pons, Chirac's minister for overseas territories and overseas departments, said the participation level "went beyond our most optimistic forecasts."

The vote was 98.3 percent in favor of maintaining the status of French overseas territory, officials announced. The result was a foregone conclusion since opponents among the indigenous Melanesians, called Kanaks, had urged a boycott. This meant that there were few negative votes and that the size of the turnout was the only real issue.

Yann Celene Urgegei, a leader of the separatist Kanak Socialist National Liberation Front, said after the vote that his movement "categorically rejects" the referendum and called for a new election in which only Kanaks would participate.

"The Kanak people remain the only legitimate people of this land," he said in a statement. "They reject the results of this fake and antidemocratic referendum, which settles nothing and does not conform with the principles and practices of the United Nations."

According to French officials, the native Kanaks now make up about 40 percent of the 140,000 inhabitants on the island, which is about 1,100 miles east of Australia. Residents of European heritage make up the second-largest group, with about 38 percent. The rest of the population is divided among Wallisians, Polynesians and others, chiefly Asians.

The first European to visit New Caledonia was Capt. James Cook in 1774. It was settled by British and French missionaries and became a French colony in 1853. It became a French overseas territory in 1946 and since then has gained increasing autonomy from the government in Paris.

After the violence in 1984, the then Socialist government sought to meet Kanaks' demands by granting them autonomous institutions in three of the island's four regions and a form of overall independence that would have retained close links with France. This was rejected by the white population and repudiated by Chirac's government when he came to power in March 1986.

The referendum organized by Pons today was designed to provide a basis for continued French rule during which, officials have said, the government in Paris will carry out reforms to meet Kanak demands for greater autonomy and a larger share of the economy.

Jean Poperen, a Socialist leader, pointed out that the outcome resulted from a very high turnout in the capital, Noumea, and other towns where Europeans and Asians predominate, but a low turnout in rural areas where Kanaks are the majority. This means the island's population remains split as before, he told a radio interviewer.