National park units affect everybody from the hiker staring in awe at the spindly, unearthly sweep of Landscape Arch to the pilot of a speedboat whipping across Lake Powell with spray flashing from its bows.

Our country's national park units were created to preserve the most important parts of our historical and natural heritage, although some regard the management of them as stumbling blocks to progress.

In 1916, Congress established the National Park Service, declaring that the fundamental purpose of the parks, monuments, and reservations is to conserve the scenery, the natural and historic objects and the wildlife therein, and to provide for the enjoyment of those in such manner that will leave them unimpaired for the enjoyment of future generations.

That lofty goal is still the working ideal, according to Park Service Director William Penn Mott Jr.

"It is through our parks that we have direct physical contact with our heritage," he said.

"If the Smithsonian is the nation's attic, the National Park Service is surely the storehouse of our culture's greatest treasures," he said.

America has 343 National Park Service units, 49 of them national parks. The system has 16,000 full-time employees and 10,000 to 12,000 seasonal workers hired for the summer. The units attract more than 280 million visitors per year, and the number is growing.

Park areas are an expression of America's ideals of protection, love for nature, and touching of the land.

But they are also affected by politics, state-federal relationships and the potential for making money. An overview follows.

Money:

Park units add a huge contribution to the economy, both directly and indirectly. Utah is a prime example.

Denis P. Galvin, deputy director of the National Park Service, estimated the annual payroll for park service establishments in Utah totals $15 million. Interviewed during the National Park Service superintendents' conference, Galvin said items such as road construction added another $15 million to the Utah economy, while the investment of the concessioner at Glen Canyon National Recreation Area on the Utah side alone amounted to $50 million.

Meanwhile, visitors spend between $50 and $100 per day. "You're talking about an industry that pretty quickly adds up to over $100 million, that employs literally thousands of people directly, in midsummer in Utah.

"I don't propose to view parks coldly as an industry, but if you do it's a non-polluting industry. It's an industry that doesn't even put great impacts on local systems on a year-round basis."

Galvin said park tourism in Utah "has taken on a very strong international character.

"I don't know whether that is the result of the aggressive marketing program that the state has undertaken, but there's just a real substantial number of European visitors coming to Utah parks at this time, particularly from Germany."

The influx from various countries is in proportion to the strengths of their currencies _ underscoring the parks' economic benefits. Obviously, if marks earned in Dusseldorf are exchanged for dollars that are spent in Springdale, Washington County, Utah's economy benefits.

Destry T. Jarvis, vice president of the nonprofit National Parks and Conservation Association, said parks provide a hub of tourism in all 50 states.

Tourism is the number one, two or three economic contributor in each state west of the Mississippi, he said. More and more companies relocate to Utah because it's an attractive state.

More people benefit from the economics of tourism than uranium mining or timber cutting, Jarvis said.

Politics:

Of all the problems that the National Park Service has, the most difficult to prove or disprove are claims of political meddling.

In a speech to the National Park Service supervisors who met earlier this month in Grand Teton National Park, Wyo., Rep. Bruce F. Vento, D-Minn., attacked those "who, contrary to the Congress' direction, are trying to uphold the belief that `all lands are created equal."'

Vento is chairman of the House Committee Subcommittee on National Parks and Public Lands.

His gibe referred to conflicts with other federal agencies whose goals might interfere with parks - the Bureau of Land Management, for instance, which could OK development on park borders.

He thinks the Interior Department, which oversees most of these federal agencies, refuses to give parks preference and that the department's political bosses interfere to prevent park service professionals from being effective advocates for the parks.

That blast was aimed squarely at William P. Horn, the 37-year-old assistant secretary of the Interior Department for fish, wildlife and parks.

The same day as Vento's speech, Horn affirmed his belief that Congress never declared the Park Service to be superior to other agencies.

"They (federal land agencies) all have missions, and our job is to carry out those missions," he said. If the BLM is interested in some activity that could harm a park, then negotiations are carried out between the agencies.

The Interior Department has a conflict-resolution program, he said. It intends to make sure that "the Park Service can gets its oar in the water" at the very beginning of some conflict.

Vento accused the Reagan administration of politicizing the National Park Service. Meanwhile, he said, pressure on parks is increasing, and people see park resources being seriously degraded.

"The result of these conflicts has been a rapidly escalating process whereby professional resource managers' decision-making has been overshadowed by political decision-making," he said.

"Heaven help you if the professional National Park Service should say no to a water project that harms the resources of the park or no to development that mars the integrity of a site - or any of the other no's you all have to say or should be saying every day," he told the superintendents.

Using a Utah issue as an example, Vento said it makes no sense to try to protect the ancient ruins at Hovenweep National Monument "and then have BLM, in an offhand manner, start leasing the lands in the immediate area for oil and gas drilling."

Paul Pritchard, the president of the nonprofit National Parks and Conservation Association, charged that political control of the National Park Service amounts to muzzling its professional experts.

"It seems that people have expressed a position, (and) the signal has been if you disagree, even when based on your best professional judgment, you're going to get a reprimand."

But Horn defended politics as a natural part of decision-making.

"The process is an inherently political process, in the classical Greek sense of the words - because everybody participates," he said.

As an example of political wheeling and dealing, he cited his personally investing "two years of very hard negotiations, behind the doors," to secure introduction of a bill to designate the Tall Grass Prairies National Park.

He denied that the Park Service is muzzled but said there is "what I call creative tension" between himself and Park Service director Mott.

"Bill Mott's not a shrinking violet. I'm not a shrinking violet," Horn said. "I have every respect for Bill Mott. We don't always see eye to eye."

"There's probably less political oversight of the Park Service right now than there was anytime in the past," he said.

State-federal relations:

During the last week of 1987, the Utah Division of State Lands gave Garfield County title to one square mile within Capitol Reef National Park - and there was no secret about why the county wanted the land.

Garfield County Commissioner Tom Hatch said, "we're going to use that as a bargaining chip."

The county intends to use it to force the federal government into funding improvements to the Burr Trail, a 66-mile road that crosses Capitol Reef National Park for a few miles.

This was not the first time state land in Capitol Reef has created severe problems for parks. In the 1970s, a ripple-rock mining operation was approved by the state on Utah property within the park. Eventually, the park acquired the land involved.

In another case, Utah officials are pushing hard to trade land within Glen Canyon National Recreation Area for other property on the shore of Lake Powell - so the state can build a new marina.

Mott insists that Glen Canyon can handle no more visitors beyond the numbers generated through planned resort expansions. He opposes the trade.

But state officials are determined to get the new marina, and they have allies in high places. Both Interior Secretary Donald Hodel and Assistant Secretary Horn, are committed to seeing if some kind of arrangement might be worked out.

"For years I've maintained that the greatest conflict in direction and purpose among the states between parks and other users was in Alaska," said National Parks and Conservation Association representative Jarvis.

"But now I've revised that over the last year and a half, and I have to say that I think the greatest tension and the worst divergence - poles apart - between park system policy and the direction of public officials is in the state of Utah."

According to Mott, park resources are increasingly vulnerable to a complex set of factors that originate outside park boundaries.

"Because of this vulnerability, the margin of error in managing of parks is extremely small."

Some legal scholars contend that the answer to threats is already in the law: Park officials have the right to take action outside park borders to protect important resources.

University of Utah law professor William J. Lockhart, a long-time supporter of the national parks, wants the Park Service to be much more aggressive in meeting external threats.

According to Lockhart, parks legally are to be treated as more important than adjacent federal land. These laws are explicit that park units are to be "protected unimpaired for future generations," he said.

At the least, the Park Service could appeal some decision allowing leasing on adjacent federal land through the Interior Department's Board of Land appeals or within the Agriculture Department in the case of Forest Service actions, he said.

"We're not talking about foreclosing the use of public lands everywhere. We're talking about developments in areas which are integral to the protection of the character, the scenic beauty, the basic wildlife range which is the environment of the national parks," he said.

Americans visit the park units because they are supposed to show us what this land was once like, and teach us where we came from, he said.

Amendments to the federal law passed in 1978 say the Interior Department secretary shall not authorize activities that would derogate values and purposes for which park units were established, he said. And the legislative history is also "very explicit."

That language was prompted by cutting of giant redwoods on private timber land adjacent to Redwoods National Park, Lockhart said. The logging caused gullies to erode, dumping silt into streams running through the park. Streams in the park overflowed and undercut the redwoods there.

Because of this situation, Congress clarified the Park Service's rights, insisting it could act outside of parks to protect park values.

Both the Justice Department and the Interior Department discourage suits by either agency to define the parks' authority.

During the park superintendents' conference, Joseph Sax, a law professor at the University of California at Berkeley, also insisted that the government has the right to take action outside parks to protect park values.

The amendments are a "powerful and available tool, available to you when dangers arise from sources beyond your traditional power of control," Sax said.

Sen. Malcolm Wallop, R-Wyo., ranking minority member of the Senate Subcommittee on Public Lands, National Parks and Forests, noted at the superintendents' conference that he's been under the Park Service's waters, on top of its mountains, in its buildings, and through its monuments.

"And I am struck by the richness, of the diversity, of America's National Park System. It is the envy of the world."

Recent reports criticizing the National Park Service have raised some issues with which Americans ought to come to grips, he said. "But the fundamental report of America's National Park System is that the 280 million-plus visitors that you've had all have said `I'll see you again next year.'