Happy Fifth of July!
Celebrating the holiday with a look back at reforesting the rainforest and saving sagebrush
I hope all readers in the U.S. had a nice Fourth of July, filled with barbeque, dazzling fireworks, or however you chose to celebrate the holiday. Normally, this would be a paid posting, but in the spirit of 1776, it is free to all readers.
Thursdays are my usual days to finish up my Substack for Friday publication, but as we celebrated Independence Day with a big, long stroll through the park followed by a big, long nap, I didn’t have the time to do a good write up, so we’re dipping into the archives for this week. Before we do, I’d like to touch on a few recent political developments affecting the environment in a big way.
Prompted by
—who publishes Civil Discourse, some of the best political writing on Substack—I’ve been reading a lot about Project 2025, the Heritage Foundation’s plan for a Trump administration should he regain the White House. Most of what I’ve been reading is the project’s agenda to do away with or weaken environmental protections. The project goes way beyond that, with plans to overhaul almost the entire federal government. If you want a succinct summary of the project, the BBC recently published a pretty good explainer.I found this other interesting article through
’s Global Nature Beat. Writing for Inside Climate News, environmental reporter Marianne Lavelle explains what the recent Supreme Court rollback of the Chevron Doctrine means for climate change.
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Today’s archive is from March 2021.
Reforestation of Tropical Rainforests
For decades we have been reading about the destruction of rainforests, particularly those of Brazil.
Efforts have been made to mitigate the damage, and in some areas, there has been successful reforestation.
There are challenges to reforestation. It would be simple if all we had to do was plant a few trees and wait while the forest came back. But more than trees are lost when a landscape is transformed from a forest to a mine or a farm. Rainforest soil can be transformed when this happens or it can be completely washed away.
One assumption about rainforest soil is that it is rich in nutrients. After all, tropical rainforests are warm and moist, making for quick decomposition of dead plants and animals; so the soil should be filled with nutrients. But most soils of rainforests are quite poor in nutrients. Despite the availability of nutrients in the ground, the rains wash them away.
Nonetheless, the soil of a rainforest does some mighty important stuff. Forests are usually blanketed with leaf litter and have extensive root systems, which lead them to retain a higher water content than other areas, such as scrubland and farms.
Most tropical rainforests are in places that have months of monsoons followed by months of dry weather. During the dry months, the soils of rainforests release water into nearby watersheds, and thus can provide a reliable source of water, including for human use, year round.
So it is a logical conclusion—and scientific studies have shown—that where there is extensive deforestation in the tropics, there are large losses of fresh water in those areas.
For almost all reforestation projects in the tropics, fast-growing tree species are chosen, largely because they can take root quickly and survive the frequent typhoons and heavy rains. The storms and typhoons can cause landslides and heavy soil loss; so if you plant some fast-growing trees and they hold the soil, all the better.
But do the fast-growing trees return the soil to its original water-retaining capabilities?
Scientists put this question to the test by reforesting about a half-acre of extremely degraded rainforest in Sanya City, on the island of Hainan off the mainland of China. They planted eight separate species of fast-growing trees and compared them to the adjacent intact rainforest.
The team includes scientists associated with a number of higher learning institutions in China. Their findings were published in Frontiers in Ecology and Evolution in February 2021.
The area had been degraded by 20 years of limestone mining by the cement industry, reducing it to mostly bare, rocky soils with minimal plant life. The researchers planted in 2016 and conducted their sampling in 2019.
Three years later, no landslides had occurred in the reforested areas. The scientists measured the water content of the soils throughout the year, from the monsoon season through the dry season. The water content of the soil of the slow-growing trees remained almost constant throughout the year, decreasing only by eight percent during the dry season, but the water content of the soil of fast-growing species declined by 90 percent in dry periods.
It turns out that the faster-growing trees use more water than the slower-growing trees that make up most of a tropical rainforest.
Because fast-growing trees do protect the soil from typhoons, the authors of the study recommended that, once the fast-growing trees are established, the dominant slow-growing species should be reintroduced among the established trees to make for a fully functioning forest with water-retaining ability.
Plans to Fight the Declining Sagebrush Ecosystem
Other interesting conservation work is going on in the American Southwest to save the sagebrush. If you have ever been among the Southwest sagebrush, you know that it is sublime, a wonder to walk through. Sagebrush can vary from impassable waist-high thickets to sparse expanses of sweet-smelling shrubs and succulents. In the U.S., the sagebrush ecosystem comprises the largest interconnected habitat type, ranging from Montana, Wyoming, and Colorado to the coastal states of Washington, Oregon, and California. In all, there are 175 million acres of sagebrush in the U.S.
A new report from a consortium that includes the U.S. Fish and Wildlife Service, the Bureau of Land Management, the U.S. Geological Survey, state wildlife agencies, and universities describes the decline of the ecosystem.
The report details encroachment from sprawl, mining, and agriculture. In the past 40 years, there has been a greater influx of people and houses, cars, roads, and shopping malls through this part of the country. Areas that had been thought too hot and dry for humans have now become attractive places to live, due, mostly, to the development of home air conditioning.
Invasive species also take their toll. Among the most insidious are the invasive grasses, such as cheatgrass. The grasses dry out during the dry summer months, providing ready fuel. Add increased chances of ignition from cigarettes, barbecues, sparks from our machines, and you wind up with large-scale fires that have never been seen before in the American West.
These big fires can occur more frequently than what the ecosystem has evolved to handle. This can lead to what is known as “type conversion,” in which the nonnative grasses totally take over and convert the sage land to grassland. I’ve seen where this has already happened in California: expanses of grasses where sages used to be. Climate change promises to exacerbate this problem.
All is not doom and gloom. The report lays out concepts and techniques for restoration, including communication and outreach to enhance grassroots conservation efforts. So if you live around sagebrush, go join your local “I Love My Sagebrush” organization. You’ll be glad you did.