Amazon's black earth. A miracle cure?

we've all heard about the catastrophic destruction of large parts of the Amazon rainforest in recent decades haven't we looks like it's had quite a roller coaster ride ever since the military Junta decided to build the trans-amazonian highway right through the middle of it back in the late 70s that enabled them to incentivize Brazilians from the rest of the country to move in chop down trees and cultivate the land for farming and cattle rearing by the mid 90s it was all getting a bit out of hand and there was rapidly growing opposition to the initiative among the Brazilian public who'd not fail to notice the devastation that was happening right on their own doorstep that ultimately led to the election of Louis Ignacio Lula de Silva in 2003 during his first time as president deforestation dropped by 70 percent to the lowest rate since records began after Lula left office in 2010 though there was a gradual creep back upwards for a few years followed by a very sharp uptick when a right-wing supporter of unregulated logging Mining and Industrial agriculture got voted into power thankfully the Brazilian public realized their mistake and in a move that few would have predicted they voted Lula de Silva back in for a second term Lula is now reinstating the regulatory policies that were so successful the first time around so with any luck we may start to see the graph line falling once again and now new research suggests the Amazon could be a catalyst for similar levels of forest Restoration in other parts of the world too thanks to a phenomenon you may already know as Terra Prater or black Earth a team of Brazilian scientists has just published a comprehensive analysis of this remarkable soil and I have to say the results have been pretty amazing hello and welcome to just have a think according to the Smithsonian Magazine human beings were living quite happily in the Amazon rainforest for about 10 000 years or so before we Europeans turn up and started making a bloody nuisance of ourselves over Generations those indigenous folks learn how to enrich the otherwise fairly poor and unproductive soil so that they could grow their own food and sustain a lifestyle in total balance with all the other ecosystems that surrounded them think of it like an idyllic scene out of Avatar but with less of the blue they achieved this soil transformation by adding charcoal from their cooking and refuse fires and by spreading in animal bones broken pottery compost and manure I imagine it was very much a trial and error thing for a while but over the course of many hundreds of years they ended up with a very dark and extremely nutrient-rich soil but is now officially known as Amazonian Dark Earth or Ade but actually referred to by most people as Black Earth or Terra Prater the authors of this new paper conducted experiments to see if they could bring degraded soil from croplands Back to Life by adding some of the good stuff from the Amazon the plan was to simulate the conversion from pasta land to Forest restoration by taking the degraded soil as their control and adding just 20 percent of Ade to see what results they could achieve compared to 100 Ade soil the researchers set up 36 4 liter pots inside a greenhouse with an Ambient Air Temperature of 34 degrees Celsius that's a fair bit warmer than the current average Amazon temperature which sits somewhere between 22 and 28 degrees Celsius but the team were Keen to mimic the likely temperatures that will become prevalent as global warming continues throughout the course of this century 12 of the pots contain just degraded soil another 12 had an 80 20 mix of degraded soil and Ade and the remaining 12 contained 100 Ade each pot was initially planted out with a grass species called uracila brazantha which I've obviously never heard of but which the horticulturalists among you may recognize as Palisade grass that's apparently a common forage plant for livestock in Brazil after 60 days of growth the grass in each pot was chopped right back so that only its roots remained that gave the research team a substrate that mimicked soil conditions in regions that had been targeted for reforestation then it got a bit more convoluted so bear with me each group of 12 pots was divided into three subgroups of four pots the first group of four was planted out with seeds from a tree species called sacropia pachystakia otherwise known as ambe pumpwood this is a species that typically first colonizes any new area of forestation the next week before pots received seeds from a secondary tree species called Pelt forum dubium and the final set of Parts got Siege from what the scientists call a climax species their words not mine called cedrilla facilis or Cedro Blanco so now they had three different plant types in three different types of soil each with four replications then they went away and let nature do its thing for 90 days at the end of that phase the researchers measured plant height and root size and collected the aerial part of the plants to measure dry matter production which is apparently the most important characteristic when measuring plant development the plant tissues were dried in an oven at 60 degrees Celsius for 48 hours then weighed and analyzed to evaluate the amount of organic matter its pH level and the content of key soil health indicators including phosphorus potassium calcium magnesium aluminum sulfur Boron copper iron manganese and zinc they also assess the soil texture and sense some of it off for DNA extraction and for what they refer to as Downstream molecular procedures so let's cut to the chase then shall we what the researchers discovered was that the tree species planted in soil with only a 20 addition of Ade showed a very similar level of performance to the tree species planted in 100 Ade and significantly higher than the tree seeds planted in the degraded control soil carbon stocks were increased and there was a demonstrable Improvement in microbial richness in the soil which now contains several microorganisms that were beneficial to the trees that means the folks engaged in reforestation projects not just in the Amazon but all over the world don't need to go to the almost impossible lengths of completely replacing native soil with Amazon Dark Earth it turns out they can achieve just as significant improvements in soil Health simply by using Ade as an additive and in fact the researchers recommend that now each of the ingredients has been scientifically isolated and identified the original soil should be left well alone and instead it's chemical and structural makeup should be replicated in Horticultural Laboratories so there's enough for everyone without having to plunder the original soils that have taken thousands of years to develop in the Amazon itself environmentalists and some horticulturalists point out that for Millennia before the Romans brought us the concept of Sanitation human beings all over the world were using their own waste to enrich soils to help them grow food you could say it's become something of a lost art if you like no one's suggesting you pop out back and start enthusiastically pooping all over your own garden though that might put a strain on your relationship with the neighbors and in any case raw human waste contains quite a lot of pathogens that you don't want anywhere near you and certainly not in your soils but after a proper amount of composting time it becomes a material very high in many of the same nutrients found in Terra Prater which makes it an extremely good soil conditioner especially if mixed with Organic animal and plant matter and biochar which is a type of charcoal made from biomass through a pyrolysis process that actually sequesters carbon dioxide from the atmosphere there's even a school of thought that suggests this practice may have represented an evolutionary Advantage providing nutrient Pathways for humans to inhabit and develop regions of the planet that had depleted soil or even almost no soil at all like deserts for example whatever the historical reality may have been the modern reality is that restoring our Landscapes holistically worldwide has now become a crucial element of climate mitigation this map from the website Global Forest watch shows the area of tree cover lost globally between 2001 and 2021 mostly for logging and the production of wood pellets for the rapidly growing and definitely not carbon neutral biomass industry the good news is that reforestation initiatives are now gaining Traction in many parts of the world in 2011 the bond challenge was launched by the international Union for conservation of nature with the goal of restoring 3.5 million square kilometers of previously degraded Land by 2030. that's an area 10 times the size of Germany to date there are 61 countries involved across all the inhabited continents with pledges covering about two-thirds of that total and it's showing very tangible hard-nosed economic benefits too every dollar spent on Forest restoration is estimated to produce something like nine dollars in economic benefits to the country involved the folks at the bond challenge reckon that if fully implemented the initiative could result in an annual Global gain of some 76 trillion dollars in 2020 bird life International the wildlife conservation society and the World Wildlife Fund launched their own initiative called one trillion trees which I suppose is pretty self-explanatory really the United States has made the bizarrely specific pledge to conserve restore and grow more than 995 million trees by 2030 and China has pledged to get more than 70 billion trees in the ground as part of their never-ending battle with the Gobi desert and now as part of their drive towards net zero in Africa 11 countries in the sahil Sahara region have joined forces to combat land degradation and restore native plant life to a landscape that was once rich with biodiversity and vegetation this kind of ostensibly encouraging news does come with a couple of very important caveats though environmentalists have raised concerns that while promoting nature at large scales is definitely the right thing to do the world must be careful that it doesn't get distracted from the main task at hand which is to decarbonize our modern way of life that means keeping the pressure on the fossil fuel companies and agribusinesses to rapidly downsize their operations and of course with non-native species are indiscriminately planted or if organizations engage in the dangerously misguided practice of creating vast ways of monoculture plantations that destroy biodiversity and wreck indigenous ecosystems then we may find ourselves doing more harm than good there are real beacons of positivity in some parts of the world though Costa Rica is a great example since 1996 the government there has been making payments to rural areas to fight poverty and halt deforestation the result of that initiative is that Costa Rica has seen its rainforests double in area transforming itself from a country with one of the world's highest deforestation rates in the 1980s to a nation now centered on eco-tourism attracting visitors with the opportunity to move between Coastal Marine reserves and cloud forest in a single day that's boosted the country's economy and accelerated progress towards carbon neutrality and hope is Rising once again in Brazil itself deforestation in Brazil's section of the Amazon rainforest has apparently dropped by 61 during the first month of Lula de Silva's second term as president only time will tell if he can make that stick but maybe just maybe there are some signs that humanity is actually capable of doing the right thing from time to time that's it for this week thanks as always to our amazing patreon supporters who keep me going and enable me to keep ads and sponsorship messages out of all these videos if you feel you could support the development of the just have a think Channel and you'd like the chance to influence future content then you can get involved with all that by visiting patreon.com forward slash just have a think where you'll get early access to all my videos plus exclusive additional monthly content from me and if you feel I've earned your support here on YouTube then you can demonstrate that absolutely for free by subscribing and hitting that like button it's that easy to do that you just need to click down there or on that icon there as always thanks very much for watching have a great week and remember to just ever think see you next week [Music]

Channel: Just Have a Think

Views: 91,076

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Id: aT2ji_tdHG0

Length: 13min 3sec (783 seconds)

Published: Sun Jun 04 2023