The U.S.-Mexico border wall will have six adverse effects on the U.S. environment

Written by: Laura Parker

President Trump is pushing for a border wall between the U.S. and Mexico, a section of the eastern part of the city of Nogales, Arizona. Still, environmentalists say it will create serious problems. Photo by Richard Misrach, nat geo image collection

People who work and live in the southern U.S. border will tell you that the farther away the political debate takes place, the more detached you are from the reality of border living. The recent debate in the U.S. government over President Trump's request to spend $5.7 billion on a border wall in the border area has re-established this view by a debate about whether the wall should be concrete or steel bars.

The border wall was built to prevent Mexicans from entering the United States. However, in global history, examples abound of the wall's inability to prevent determined people from entering. Janet Napolitano, who served as Arizona governor and secretary of homeland security in the Obama administration, was well known for repeated points: "Give me a 50-foot wall and I'll find you a 51-foot ladder right away." "In fact, the number of people arrested in the United States for illegal entry has just hit a 45-year low, so what really needs to be debated is the issue of immigration law, not whether a border wall should be built at the U.S.-Mexico border."

In fact, it is time to discuss the unintended consequences of building a border wall, not just whether it should be concrete or steel bars.

"No matter what kind of wall they build, it will cause damage to the natural habitat," said attorney Bob Dreher, leader of The Guardians of the Wild Animals. "It's a real question about the impact of a permanent barrier on north America's most sensitive ecoregions."

Here are some of the potential impacts of building a boundary wall:

1. Threaten diverse landscapes

Stretching more than 3,100 kilometers from the Gulf of Mexico in Texas to the Pacific Ocean in California, the U.S.-Mexico border spans some of the most diverse topographies in the United States, including six separate ecological zones, desert shrublands, forests, and wetland swamps, ranging from freshwater and saltwater areas.

The border wall will divide the habitat of 1,506 native animals and plants, including 62 species classified as critically endangered. A team of conservation experts, including the prominent ecologist and naturalist Edward O. Wilson, said in a study published in the Biological Sciences last July that border walls put these habitats at risk. Border walls exacerbate soil erosion, alter patterns of natural water flows and wildfires, and increase the risk to humans and animals by blocking escape routes.

2. Exacerbate flooding

During the George W. Bush administration, arizona flooded after a 1,100-kilometer wall was built on the U.S.-Mexico border. When floods erupt during the rainy season, the fence acts as a dam. In 2008, during a 90-minute summer thunderstorm, at the Organ Cactus National Reserve in southwest Arizona, an 8-kilometer-long, 4.6-meter-high parapet net blocked a large amount of debris, causing the water to accumulate into a pool of 0.6-2.1 meters deep.

The thunderstorm also caused flooding in the city of Nogales, Arizona, 106 kilometers south of Tucson, causing millions of dollars in property damage to the city of Nogales in The Mexican province of Sonora. In 2011, another flood at the Organ Cactus National Conservation Area washed away a section of the wall. In 2014, during a storm, the U.S.-Mexico border wall was blocked by debris, and flooding resumed in the Twin Cities of Nogales.

3. Endanger wild animals and plants

A study published last July in the journal Biological Sciences said the border wall could isolate 1/3 of the 346 species of wildlife from its habitat of 50 percent or more. This reduces and isolates animal populations, limiting their chances of finding water, food and mates, thereby increasing their risk of survival. Walls can also prevent wildlife from escaping fires, floods or heat waves. Even the partridge is in danger because they do not exceed 1.5 meters above the ground when flying.

The border wall would also disrupt the seasonal migration of the peninsula's bighorn sheep that operate between California and Mexico, affecting where they enter water and produce. The inability to cross the border has dispersed the population of the North American forkhorn antelope, reducing the chances of Mexican gray wolves, jaguars and ocelots rebuilding their territories in the United States. Jaguars were once active on both sides of the Rio Grande, but now have almost disappeared from Texas.

Restrictions on the movement of animals in turn affect plants. According to a report by the Organization of Wildlife Defenders, seeds of legume shrubs are more likely to germinate after passing through the digestive systems of wild boars and coyotes.

4. Cut off the river

The winding Rio Grande is the official dividing line between the United States and Mexico, and has long been considered a geographical barrier to the construction of a border wall. The river sometimes changes course and floods during the spring. Building a border wall on the north side of the Rio Grande would cede control of those lands to Mexico, isolating the homes and properties of U.S. citizens on the Mexican side.

That view has changed. Last spring, congress approved a $1.6 billion grant to build more border walls, most of it in Texas. The Department of Homeland Security plans to build a 40-kilometer border wall on the flood levees in Highland County, sometimes more than 1.6 kilometers from the border. Nearby County Starr is currently planning to build another nearly 13 kilometres of border wall.

5. Destruction of wildlife sanctuaries and parks

Under consideration, the border wall would cross seven wildlife sanctuaries in Texas, including the Grand Valley Lower National Wildlife Refuge and The Great Bend National Park, which are remote and considered one of the best stargazing spots in the Lower 48 States and are therefore prized in numerous national parks.

At the National Butterfly Center in Mission, Texas, more than 200 species of butterflies inhabit the banks of the Rio Grande, and a border wall will separate the 0.4-square-kilometer protected area and place 70 percent of the reserve on the Mexican side. In addition, other border wall plans would divide a wildlife sanctuary and a state park, placing most of the land on the Mexican side.

After backlash, the Department of Homeland Security shelved plans to build a border wall at the Santa Ana National Wildlife Refuge in Alamo, Texas, which is home to more than 400 species of birds, banded armadillos and endangered wildcats.

6. Affect the implementation of environmental regulatory laws

The construction of the border wall does not have to meet the requirements of more than 30 federal environmental laws, such as the Endangered Species Act, the National Environmental Policy Act, the Clean Air Act, and the Clean Water Act. That's because the Real Identity Act passed by the U.S. Congress in response to the 9/11 terrorist attacks in 2005 authorized the Department of Homeland Security to violate any law in the name of national security.

As of 2006, there have been a number of lawsuits against the Real Identity Act. To date, all attempts to bring constitutional issues relating to the extension of the powers of the executive branch to the Supreme Court have failed. At present, these lawsuits are still continuing.

(Translator: Stray Dog)

Source: National Geographic Chinese Network (Official v)