The manager of the Bureau of Land Management’s environmental impact study, Linda Resseguie, said that many factors must be considered when deciding whether to allow solar projects on the scale being proposed, among them the impact of construction and transmission lines on native vegetation and wildlife. In California, for example, solar developers often hire environmental experts to assess the effects of construction on the desert tortoise and Mojave ground squirrel.

Water use can be a factor as well, especially in the parched areas where virtually all of the proposed plants would be built. Concentrating solar plants may require water to condense the steam used to power the turbine.

“Reclamation is another big issue,” Ms. Resseguie said. “These plants potentially have a 20- to 30-year life span. How to restore that land is a big question for us.”

Another benefit of the study will be a single set of environmental criteria to weigh future solar proposals, which will ultimately speed the application process, said the assistant Interior Department secretary for land and minerals management, C. Stephen Allred. The land agency’s manager of energy policy, Ray Brady, said the moratorium on new applications was necessary to “ensure that we are doing an adequate level of analysis of the impacts.”

In the meantime, bureau officials emphasized, they will continue processing the more than 130 applications received before May 29, measuring each one’s environmental impact.

While proponents of solar energy agree on the need for a sweeping environmental study, many believe that the freeze is unwarranted. Some, like Ms. Gordon, whose company has two pending proposals for solar plants on public land, say small solar energy businesses could suffer if they are forced to turn to more expensive private land for development.

The industry is already concerned over the fate of federal solar investment tax credits, which are set to expire at the end of the year unless Congress renews them. The moratorium, combined with an end to tax credits, would deal a double blow to an industry that, solar advocates say, has experienced significant growth without major environmental problems.