Nature Offers Solutions to Water Woes and Flood Risks
When the Aztecs founded Tenochtitlán in 1325, they built it on a large island on Lake Texcoco. Its eventual 200,000-plus inhabitants relied on canals, levees, dikes, floating gardens, aqueducts and bridges for defense, transportation, flood control, drinking water and food. After the Spaniards conquered the city in 1521, they drained the lake and built Mexico City over it.
The now-sprawling metropolis, with 100 times the number of inhabitants as Tenochtitlán at its peak, is fascinating, with lively culture, complex history and diverse architecture. It's also a mess. Water shortages, water contamination and wastewater issues add to the complications of crime, poverty and pollution. Drained and drying aquifers are causing the city to sink—almost 10 meters over the past century!
"Conquering" nature has long been the western way. Our hubris, and often our religious ideologies, have led us to believe we are above nature and have a right to subdue and control it. We let our technical abilities get ahead of our wisdom. We're learning now that working with nature—understanding that we are part of it—is more cost-effective and efficient in the long run.
Had we designed cities with nature in mind, we'd see fewer issues around flooding, pollution and excessive heat, and we wouldn't have to resort to expensive fixes. Flooding, especially, can hit people hard in urban areas. According to the Global Resilience Partnership, "Floods cause more damage worldwide than any other type of natural disaster and cause some of the largest economic, social and humanitarian losses"—accounting for 47 percent of weather-related disasters and affecting 2.3 billion people over the past 20 years, 95 percent of them in Asia.
As the world warms, it's getting worse. Recent floods in Bangladesh, India, Pakistan and Nepal have affected more than 40 million people, killing more than 1,000. One-third of Bangladesh is under water. In Houston, Texas, Hurricane Harvey has killed dozens and displaced thousands, shut down oil refineries and caused explosions at chemical plants. Some say it's one of the costliest "natural" disasters in U.S. history.
1,200 Dead, 41 Million Affected by Flooding in India, Bangladesh and Nepal https://t.co/WhmnRqL6AU @climatecouncil @climateinstitut— EcoWatch (@EcoWatch)1504299671.0
Although hurricanes and rain are natural, there's little doubt that human-caused climate change has made matters worse. More water evaporates from warming oceans and warmer air holds more water. Climate change is also believed to have held the Houston storm in place for longer than normal, and rising sea levels contributed to greater storm surges.
A lax regulatory regime that allows developers to drain wetlands and build on flood plains has compounded Houston's problems. The city has no zoning laws, and many wetlands and prairies—which normally absorb large amounts of water and prevent or lessen flood damage—have been drained, developed or paved over. President Donald Trump also rescinded federal flood protection standards put in place by the Obama administration and plans to repeal a law that protects wetlands. Compare Houston to Amsterdam and Rotterdam, which sit below sea level. Regulation and planning have helped the Dutch cities lower flood risk and save money.
As climate disruption accelerates in concert with still-increasing greenhouse gas emissions, people are looking for ways to protect cities from events like flooding. In China, authorities are aiming to make them more sponge-like. A Guardian article explained: "Designers will concede to the wisdom of nature to ensure water is absorbed when there's an excess: instead of water-resistant concrete, permeable materials and green spaces will be used to soak up rainfall, and rivers and streams will be interconnected so that water can flow away from flooded areas." As well as offering flood protection, the measures will also help prevent water shortages.
Cities worldwide have employed many of these flood-protection measures, including in the U.S. If China goes beyond its 16-city pilot project, it will be the largest-scale deployment of such combined measures ever.
Restoring natural areas costs much more than protecting them in the first place, more intense and frequent storms and floods can still overwhelm natural defenses, and growing human populations will further stress resources, but restoring natural assets is a start.
Ultimately, we must work with nature to prevent and adapt to problems such as flooding, water scarcity, wildfires and climate disruption. When we work against nature, we work against ourselves.
Sweden's reindeer have a problem. In winter, they feed on lichens buried beneath the snow. But the climate crisis is making this difficult. Warmer temperatures mean moisture sometimes falls as rain instead of snow. When the air refreezes, a layer of ice forms between the reindeer and their meal, forcing them to wander further in search of ideal conditions. And sometimes, this means crossing busy roads.
- San Antonio, Texas Unveils Largest Highway Crossing for Wildlife in ... ›
- Wildlife Crossings a Huge Success - EcoWatch ›
EcoWatch Daily Newsletter
- Climate Change Will Be Sudden and Cataclysmic Unless We Act Now ›
- There's a Heatwave at the Arctic 'Doomsday Vault' - EcoWatch ›
- Marine Heatwaves Destroy Ocean Ecosystems Like Wildfires ... ›
By Aaron W Hunter
A chance discovery of a beautifully preserved fossil in the desert landscape of Morocco has solved one of the great mysteries of biology and paleontology: how starfish evolved their arms.
The Pompeii of palaeontology. Aaron Hunter, Author provided<h2></h2><p>Although starfish might appear very robust animals, they are typically made up of lots of hard parts attached by ligaments and soft tissue which, upon death, quickly degrade. This means we rely on places like the Fezouata formations to provide snapshots of their evolution.</p><p>The starfish fossil record is patchy, especially at the critical time when many of these animal groups first appeared. Sorting out how each of the various types of ancient starfish relate to each other is like putting a puzzle together when many of the parts are missing.</p><h2>The Oldest Starfish</h2><p><em><a href="https://www.biorxiv.org/content/10.1101/216101v1.full.pdf" target="_blank" rel="noopener noreferrer">Cantabrigiaster</a></em> is the most primitive starfish-like animal to be discovered in the fossil record. It was discovered in 2003, but it has taken over 17 years to work out its true significance.</p><p>What makes <em>Cantabrigiaster</em> unique is that it lacks almost all the characteristics we find in brittle stars and starfish.</p><p>Starfish and brittle stars belong to the family Asterozoa. Their ancestors, the Somasteroids were especially fragile - before <em>Cantabrigiaster</em> we only had a handful of specimens. The celebrated Moroccan paleontologist Mohamed <a href="https://doi.org/10.1016/j.palaeo.2016.06.041" target="_blank" rel="noopener noreferrer">Ben Moula</a> and his local team was instrumental in discovering <a href="https://www.sciencedirect.com/science/article/abs/pii/S0031018216302334?via%3Dihub" target="_blank" rel="noopener noreferrer">these amazing fossils</a> near the town of Zagora, in Morocco.</p><h2>The Breakthrough</h2><p>Our breakthrough moment came when I compared the arms of <em>Cantabrigiaster</em> with those of modern sea lilles, filter feeders with long feathery arms that tend to be attached to the sea floor by a stem or stalk.</p><p>The striking similarity between these modern filter feeders and the ancient starfish led our team from the University of Cambridge and Harvard University to create a new analysis. We applied a biological model to the features of all the current early Asterozoa fossils in existence, along with a sample of their closest relatives.</p>
Cantabrigiaster is the most primitive starfish-like animal to be discovered in the fossil record. Aaron Hunter, Author provided<p>Our results demonstrate <em>Cantabrigiaster</em> is the most primitive of all the Asterozoa, and most likely evolved from ancient animals called crinoids that lived 250 million years before dinosaurs. The five arms of starfish are a relic left over from these ancestors. In the case of <em>Cantabrigiaster</em>, and its starfish descendants, it evolved by flipping upside-down so its arms are face down on the sediment to feed.</p><p>Although we sampled a relatively small numbers of those ancestors, one of the unexpected outcomes was it provided an idea of how they could be related to each other. Paleontologists studying echinoderms are often lost in detail as all the different groups are so radically different from each other, so it is hard to tell which evolved first.</p>
- Biden Reaffirms Commitment to Rejoining Paris Agreement ... ›
- Biden Likely Plans to Cancel Keystone XL Pipeline on Day One ... ›
- Joe Biden Appoints Climate Crisis Team - EcoWatch ›