Voicing concerns that Americans are losing their connection with nature -- and that natural areas are falling victim to sprawl and pollution -- the Obama administration is inviting hundreds of sportsmen, environmentalists and other champions of the outdoors to Washington next month for a summit on conservation.

The White House Conference on America’s Great Outdoors, on April 16, will focus on how to conserve the land with a focus on local leadership, as opposed to a heavy federal government role, administration officials announced Friday.

Under President Obama’s vision for a “21st century conservation agenda,” the federal government would bring together cities, states, tribes and nongovernmental organizations working on conservation efforts, and encourage families to spend more time outdoors, officials said.

The conference follows the trail of presidential conservation summits dating back to Theodore Roosevelt, and most recently held by Presidents Clinton and George W. Bush.

It comes when Obama, like so many of his predecessors, is struggling to balance competing pressures on public land from hunters and anglers, green groups and industry.

Oil and gas companies have criticized Obama’s Interior Department for revoking some drilling leases -- many of them near national parks -- issued under Bush.

Congressional Republicans have accused Interior Secretary Ken Salazar of pushing to “lock up” swaths of federal land in the West, after the public release of a department document suggesting possible sites for new national monuments.

Salazar has defended the revoked leases and dismissed the monument document as an early draft, assuring Western lawmakers that the administration won’t declare new monuments without public input.

Sport fishing groups, fueled by Internet rumors, have said in recent weeks that the administration could be preparing new restrictions on recreational fishing -- assertions that the White House and fisheries officials deny emphatically.

Even environmentalists, while largely pleased with the administration’s stance on public lands, have said that Obama has not gone far enough to block mountaintop coal mining.

An administration official said the Great Outdoors conference is aimed, in large part, at alleviating fears of the federal government locking up land unilaterally.

“This conference is about starting a conversation about conservation in America,” the official said, speaking on condition of anonymity because the summit had not officially been announced, “and about learning more about what local communities, tribes and stakeholders are doing to protect the places they love.”

jtankersley@latimes.com