Can America’s National Parks defeat the developers at their gates? 

To learn what most endangers national parks, on the occasion this month of the National Park Service’s 100th birthday, look no farther than Mojave National Preserve, a vast swath of exquisite desert panoramas halfway between Los Angeles and Las Vegas. These days, national parks struggle with all sorts of urgent threats, such as climate change and deteriorating services and infrastructure as a result of underfunding, but Mojave’s biggest menace isn’t what’s happening inside the preserve, it’s what increasingly surrounds it.

Three industrial-scale solar farms adjacent to the preserve are already in operation, the Interior Department has approved a fourth, and a wind farm proposal is getting serious consideration. One of the solar farms, Ivanpah, made news recently for frying birds and setting itself on fire.

Soda Mountain, the solar project approved for construction on Bureau of Land Management land next to the Mojave preserve, would be the largest industrial site within 100 miles. It would isolate and possibly doom a portion of the desert’s depleted population of bighorn sheep, and like the other energy projects, it would be visible from the preserve. By generating enough renewable electricity for 86,000 homes, the project would address one environmental problem, climate change, while creating others: It would show that an energy project can be renewable without being green.

What’s most puzzling about the Interior Department’s approval of Soda Mountain is that its siting is unnecessary – the department’s own Renewable Energy Conservation Plan has identified hundreds of thousands of acres of land elsewhere in Southern California appropriate for renewable energy projects such as Soda Mountain. Energy developers usually line up customers before they launch a project of Soda Mountain’s scale, but Bechtel, the giant engineering company that owns the project, hasn’t found buyers for its electricity. The company assumed that the Los Angeles Department of Water and Power would be its main customer, but DWP bowed out a year ago on the grounds that the project was environmentally destructive (the electricity’s high cost may have been a more telling reason).

Without DWP’s involvement, Bechtel probably has lost access to the utility’s existing transmission lines, and will have to build new, environmentally damaging ones to send the electricity elsewhere. That means the environmental impact statement Bechtel submitted to win the Interior Department’s approval is out-of-date and may have to be revised. But none of this has scuttled the plan.

The park assault represented by Soda Mountain is far from unique. Many of the Park Service’s 412 properties are experiencing destructive forms of adjacent development that threaten their ecological systems and cultural integrity – the attributes that make them worth protecting in the first place.

“Probably 80% of my job is dealing with the constant stream of activities that corporations want to do on the borders of national parks, outside the jurisdiction of the Park Service, that fundamentally threaten the parks,” Mark Wenzler, senior vice president of conservation programs at the National Parks Conservation Assn., told me.

The threat strikes directly at the mission assigned to the service by the 1916 legislation that created it: to leave parks’ scenery and wildlife “unimpaired for the enjoyment of future generations.” The obvious villains are the corporate interests behind mines, dams, pipelines, oil and gas drilling facilities, solar and wind farms, electric transmission lines, housing tracts and shopping malls, but government agencies also bear responsibility. Much of this development occurs on public land, and it requires the agencies’ approval. While the National Park Service and U.S. Fish and Wildlife Service typically oppose industrial-scale development projects on park borders, their position is often ignored by the BLM, U.S. Forest Service, Army Corps of Engineers and Bureau of Reclamation, which have been more interested in fulfilling President Obama’s ambitious energy goals.

Other agencies “generally don’t have an awful lot of sympathy” for the park service’s position, Mike Soukup, the National Park Service’s former chief scientist, told me. “They say, ‘Our jurisdiction goes from this point to this point, and we can do whatever we need to do.’ ”

National parks were once thought of as unchanging, postcard-ready vignettes of natural beauty, whose management chiefly required shepherding visitors through them. But like all other living things, parks respond to their surroundings. For the first six or seven decades after the Park Service was established, many parks flourished in the absence of nearby development, reinforcing the notion that they require minimal care.

But now industrial development and science have caught up to them. Biologists studying islands discovered that isolation weakens ecosystems: the smaller the island, the fewer species it supports. As development surrounds the parks, they become more and more like islands. Their ecosystems usually extend far beyond their boundaries, and even distant alterations to those systems can reduce the number of species inside the parks. In addition, migratory animals that pass through the parks need access to the entire length of their trails, no matter how far the trails extend from the parks. Helping parks thrive thus means limiting destruction throughout their ecosystems and establishing wildlife corridors for migratory animals. The advent of climate change and the stress it places on ecosystems makes fostering of the parks’ ecological resilience all the more important.

The parks’ historical and cultural holdings are similarly at risk. For example, since 2013, the Army Corps of Engineers has been considering a proposal by Dominion Virginia Power, a subsidiary of the nation’s fourth-largest utility, to build a 17-mile transmission line across the James River and as close as 3.5 miles to Colonial National Historic Park, where Jamestown, the continent’s first permanent English settlement, was established. Some of the towers would be nearly as tall as the Statue of Liberty, and they would be equipped with flashing red lights visible from the park.

The pressure at the park gates has intensified in the last decade, as the United States has conducted a massive expansion of its energy industries. Yet energy projects can be relocated, national parks can’t. Projects such as Soda Mountain and the James River towers ought to be routinely rejected. What’s at stake isn’t just the Park Service’s admirable 100-year-old mission, but something bigger: the crucial but dwindling capacity of natural beauty to enlighten and set us free.

Jacques Leslie is a former Los Angeles Times foreign correspondent and author of “Deep Water: The Epic Struggle Over Dams, Displaced People, and the Environment.”