Speaker Mike Johnson on Thursday appointed Representative Rick Crawford of Arkansas as the new chairman of the House Intelligence Committee, a move that was seen as aligning the powerful panel more closely with the agenda of President-elect Donald J. Trump.

The appointment of Mr. Crawford came amid much consternation on Capitol Hill over Mr. Johnson’s sudden and unexpected removal on Wednesday of Representative Michael R. Turner of Ohio, who had served for three years as the top Republican on the panel and had at times been critical of Mr. Trump.

Mr. Turner had been an influential, and increasingly lonely, G.O.P. voice in support of America’s traditional role in intelligence-gathering operations and supporting allies abroad.

But he had voted to certify President Biden’s victory over Mr. Trump in 2020. Mr. Crawford, by contrast, voted to object to the 2020 election results. While Mr. Turner played a pivotal role in the Republican push on Capitol Hill to continue sending aid to Ukraine for its battle against Russian aggression, Mr. Crawford has at times voted against funding Kyiv’s war effort.

And in the wake of his abrupt ouster, Mr. Turner told people that Mr. Johnson had informed him that he was being removed because of “concerns from Mar-a-Lago,” according to two people familiar with the conversations.

Since Mr. Johnson made his move, Democrats and some Republicans have blasted the decision to remove Mr. Turner, who was known for working in a bipartisan manner. Appointment to the House Permanent Select Committee on Intelligence is one of the most serious jobs in Congress, and the lawmakers selected for the job are trusted with some of the nation’s most sensitive information.

“Mike Turner has robustly promoted the safety of the American people and the free world, and his unjustified ouster is likely being applauded by our adversaries in Russia and China,” Representative Hakeem Jeffries of New York, the minority leader, said on Thursday, calling it “shameful.”

Mr. Turner was not trusted among top aides to Mr. Trump, but was nevertheless blindsided by his defenestration.

The Ohioan was among a group of committee chairmen who visited Mr. Trump at Mar-a-Lago last weekend, where Trump aides presented Mr. Turner with a birthday cake with a candle. He appeared in a good mood and spoke briefly with Mr. Trump at the event, according to people who observed them.

But beyond the niceties, displeasure with Mr. Turner was brewing. Mr. Trump and his top aides have long viewed members of the intelligence community as adversaries, and some close to Mr. Trump view Mr. Turner as being too close to what they pejoratively call “the deep state.”

According to one person familiar with the matter, the president-elect was “not happy” to hear that Representative Mike Waltz of Florida, a member of the Intelligence Committee who is in line to be his national security adviser, had proposed bringing on a top aide of Mr. Turner’s for his National Security Council staff.

At the same time, members of the ultraconservative House Freedom Caucus, with whom Mr. Trump is close, have been angry with Mr. Turner since last year, when they accused him of being “reckless” in raising alarms about a national security threat during debate over the renewal of a key provision in the Foreign Intelligence Surveillance Act.

But both Mr. Johnson and Mr. Trump’s advisers have been adamant that the president-elect made no direct order to fire Mr. Turner.

Mr. Johnson said the decision to remove Mr. Turner from the panel was his alone and noted that the Ohioan would still serve as the House’s point person to the North Atlantic Treaty Organization.

“The House Intel Committee will play a pivotal role in this work in the new Congress, and Rick Crawford will provide principled leadership as its chairman,” Mr. Johnson said in a statement announcing Mr. Crawford’s appointment.

A person close to Mr. Johnson said the speaker viewed him as the choice of the former speaker, Kevin McCarthy, and that Mr. Johnson wanted to select his own team.

Mr. Johnson said on Wednesday that the intelligence community and everything related to the panel “needs a fresh start.”

But the change at the top of the intelligence committee was seen as a victory for the so-called America First wing of the party in a long-simmering civil war within the G.O.P.

Mr. Crawford is seen as less reliable in his support of Ukraine aid than Mr. Turner. The two men voted similarly with regards to renewing the Foreign Intelligence Surveillance Act.

In a statement, Mr. Crawford said he planned to serve as a check on the intelligence community.

“Without aggressive oversight and vigorous protection of Americans’ Fourth Amendment rights, the I.C. is prone to give in to mission creep and skirt U.S. laws,” he said. “In all our work, I pledge to preserve Americans’ constitutional rights even as we work to support the I.C. in doing everything required to collect indispensable information from our foreign adversaries.”

Mr. Johnson started remaking the committee last year to be more aligned with Mr. Trump when he appointed Representatives Ronny Jackson of Texas, Mr. Trump’s former White House physician, and Scott Perry of Pennsylvania, the former leader of the House Freedom Caucus.

He will soon have more appointments to make. In addition to the departure of Mr. Waltz, Representative Elise Stefanik of New York is also expected to join the Trump administration, creating two more vacancies.

Of all the government agencies that President-elect Donald J. Trump has threatened to shrink or eliminate, perhaps none has been a greater target than the Environmental Protection Agency.

During the first Trump administration, the nation’s top regulator of air and water pollution and industrial chemicals saw its budget slashed, leading to an exodus of employees and weakened enforcement of environmental rules.

This time, Mr. Trump could go further.

President Biden rebuilt the E.P.A. and used it to enact two powerful climate regulations aimed at cutting greenhouse gas emissions from tailpipes and power plants. But Mr. Trump has already promised to “kill” the agency’s climate regulations, and people close to the Trump transition have recommended ousting E.P.A. career staff, eliminating its scientific advisers, and closing an office that helps minority communities that disproportionately struggle with polluted air and water. There is even discussion of moving E.P.A. headquarters and its 7,000 workers out of Washington, possibly to Texas or Florida, as a way to shed employees.

The man who would carry out the dismantling is a former congressman from New York, Lee Zeldin, who is set to appear Thursday morning before the Senate Committee on Environment and Public Works.

The nomination of Mr. Zeldin baffled many, since he has little background in environmental regulation.

But Mr. Zeldin, 44, who ran unsuccessfully for governor of New York in 2022, is a Trump supporter who voted against certifying the results of the 2020 election. Friends say he has a long and loyal connection with the president-elect.

“They have a unique bond,” said Chris Berardini, a Republican lobbyist . “Republicans in New York tend to be always close. It’s a very lonely fraternity.”

The two men have something else in common, Mr. Berardini said. Last summer, Mr. Trump survived an assassination attempt at a campaign event. In 2022, Mr. Zeldin was attacked by a man with a pointed weapon at a campaign event. “Those are the subtle threads that weave into a personal relationship,” Mr. Berardini said.

While Mr. Zeldin is not experienced in environmental regulation, he and his allies point to his years representing his Long Island district, which included miles of coastline and had a bipartisan tradition of environmental conservation.

At the same time, Mr. Zeldin appears to have embraced Mr. Trump’s seemingly contradictory position: he says he wants clean air and water while he plans to erase regulations that ensure both, along with limits on the emissions of greenhouse gases from fossil fuels that are linked to stronger droughts, wildfires, floods.

Upon accepting the nomination to head the E.P.A., Mr. Zeldin wrote on X, “We will restore US energy dominance, revitalize our auto industry to bring back American jobs, and make the US the global leader of AI. We will do so by protecting clean air and water.”

Senator Shelley Moore Capito, Republican of West Virginia, who chairs the environment committee, said Wednesday on Fox Business News of Mr. Zeldin that “By being the representative from New York, he’s seen all different types of clean air, clean water issues, and the best way to solve those problems.”

But Ms. Capito, whose home state is a major producer of coal and natural gas, also appears confident that Mr. Zeldin will execute Mr. Trump’s plans.

In a Facebook post last month, Ms. Capito wrote, “Congressman Zeldin understands the need to roll back regulatory overreach, unleash American energy, and allow Americans to build again — all while protecting public health and the environment. His skill set is well suited to implement the agenda of President Trump. ”

Mr. Zeldin has not said much about whether he accepts the established science of climate change but he was a member of the bipartisan Climate Solutions Caucus in Congress. However, he voted against the Inflation Reduction Act, the nation’s first major climate law, which pumped at least $370 billion into clean energy programs.

When Gov. Kathy Hochul of New York criticized Mr. Zeldin, he responded on social media, saying, “I just voted NO because the bill sucks.”

During Mr. Zeldin’s tenure in the House, he voted against clean water legislation at least a dozen times and clean air legislation at least half a dozen times, according to a scorecard by the League of Conservation Voters, an environmental group.

However, he has boasted about securing federal funds to improve the health of Long Island Sound, and he voted for a bill that would require the E.P.A. to set limits on PFAS, damaging chemicals that are persistent in the environment and the human body. The E.P.A. under the Biden administration has set strict limits on chemicals in drinking water. In 2020, he voted against legislation to slash E.P.A.’s budget.

Senator Edward J. Markey of Massachusetts, a senior Democrat on the environment committee, said he met with Mr. Zeldin Tuesday and had “a good, candid conversation.”

Still Mr. Markey questioned his qualifications to run the E.P.A., and expressed skepticism about his commitment to guard the air and water from polluting industries.

“I’m not convinced his top priority is protecting communities and our environment,” Mr. Markey said.

On climate change, Mr. Markey said Mr. Zeldin “said he believed that human activity contributes to climate change.” But he said, “My questions go to what the E.P.A. priorities would be under his leadership.”

Lisa Friedman contributed reporting.