The Earth Story

Trees of death

This one man started planting a tree a day in an area in India that had been completely deforested. Today that forest is twice the size of Central Park and hosts elephants, rhinos, and even predators like tigers. But, the government has yet to offer protections to this new area even as it recovers. Original caption: 

Tropical soils take millennia to recover from deforestation

This large lake today is found in Guatemala, and although you see people bathing in it today, the record of human influence on this lake goes back several thousand years, to the Mayan civilization. Lakes like this one can be great records for geologists as the sediment pouring into the lakes every year can give us an idea what was happening in the surrounding area. A newly published study used sediments in 3 lakes in Guatemala and central Mexico to study how the development of the Mayan civilization affected the local soils. Soils, particularly in the tropics, are huge reservoirs of carbon. In tropical forests like the ones in Central America, that carbon can be stored and recycled by organisms for thousands of years. The carbon starts off in plants, is buried in the ground, and then eventually eroded and transported downslope to these lakes, where the compounds that started in plants are again buried in the sediment for geologists to find later.

However, deforestation for development will disrupt this cycle. Deforestation will expose the soil carbon to the atmosphere, allowing it to be consumed rapidly by microbes. The sediments in this lake, therefore, can be a record of how humans affected these soils.

A team from a number of universities collected cores from 3 lakes in Mexico and Guatemala and analyzed the abundance of specific types of leaf wax in those sediments. The leaf waxes can’t have come from any other source other than plant matter, and measuring carbon isotope ratios let the scientists confirm that the waxes came from long-buried soil carbon.

Those sediment cores gave a clear record of how the Maya civilization disrupted the soils in this area. When the Mayan civilization developed, there are clear drops in the abundance of leaf wax deposited in each of these lakes. The soil carbon was disturbed as that civilization developed, the carbon was released to the atmosphere, and there was less wax to flow into the lakes.

Furthermore, after the Mayan civilization collapsed, there were several hundred years where there was limited development in this area. Despite the limited development, the leaf wax abundances never returned to the levels observed before the Mayan civilization. Once the soil was disturbed in this area, even several hundred years was not enough to restore it to its original state.

In the most recent parts of the sediment cores, the scientists observed another decline in leaf wax, most likely associated with modern day deforestation. The overall message of this paper is; damage the soils, release the carbon to the atmosphere rapidly, and it won’t come back any time soon.

-JBB

Image source: http://bit.ly/2w0Rvf0

Original paper: https://www.nature.com/articles/s41561-018-0192-7

An interactive map has now been made available revealing the levels of global deforestation between the years of 2000 and 2012. The map has been created by analysing 654,178 Landsat images. The program looks at both forest loss and forest gain. The calculations are accurate down to about 30 meters providing enough detail to provide useful local information while still covering the whole globe. This screenshot shows forest cover loss between 2002 and 2012. Red indicates loss and black, no loss. Have a go, and see how your own country stands in relation to deforestation:http://earthenginepartners.appspot.com/science-2013-global-forest

Deforestation in Brazil will not create an economic miracle.

Some time ago, we shared an image showing the border between Haiti and the Dominican Republic, outlining the enormous difference in the level of deforestation between the two countries (http://tinyurl.com/cwm427g). We now share a new image, taken by the ASTER instrument on NASA's TERRA satellite. This one depicts the border between Western Brazil's Acre province, showing the typical herringbone pattern radiating out from forest roads caused by the human transformation of the Amazon rainforest into settled farmland, and the Northwestern Bolivian province of Pando, still covered in relatively pristine forest.

A paper just published in Environmental Research Letters details evidence that this policy of converting the Amazon rainforest into cattle ranches and soya fields, while economically beneficial in the short term, is likely to prove the opposite in the longer term. This could affect global food security, since Brazillian soya ( it is the world's top supplier) and beef are exported worldwide. The degradation of the productive capacity of the soil engendered by deforestation (via erosion and the fact that most of the Amazon's soil comes from the perpetual recycling of forest biomass above what is essentially a desert) could mean less calories to go round as the whole global food system is transformed by climate change.

The research shows that deforestation is already leading to reduced rainfall and drought, affecting the productive capacity of the newly created farmlands in what could become an uncontrollable feedback loop. The more the farmed area expands, the less productive it will be. Their models, based on what has happened so far, expect a 34% decline in pastoral productivity and a 28% drop in soya yield by 2050.

This makes an economic argument against deforestation, since the environmental ones are having trouble gaining traction within business and government circles worldwide. It adds detail to the big picture painted by Lord Stern in his report on the economic costs of climate change a few years back. While the global environmental impact of the loss of the rainforest is well studied, this is the first paper focussing on the local economic consequences, and with luck, the Brazillian government will work even harder to reduce deforestation. The researchers also point out that improved efficiency in the use of already cleared land and water resources could offset some of this productivity loss, without extending the area of converted rainforest.

More of this type of regional level research is needed, to demonstrate the effects of our environmental abuse of the Earth on our collective pocketbooks. Whether it will lead to a paradigm shift in our economic model, in which short term quarterly figures are the standard by which politicians and CEO's are judged, rather than the long term effects of their policies, remains to be seen. After all, with such short periods in office, the bad consequences are bound to happen on someone else's watch, which is basically the generational gamble we are all undertaking with the only planet we have.

Loz

Image credit: NASA

Original paper: http://iopscience.iop.org/1748-9326/8/2/024021/article

http://www.guardian.co.uk/environment/2013/may/10/amazon-clearance-agriculture-economic-own-goal

http://www.guardian.co.uk/environment/2012/nov/14/brazil-amazon-rangers-farmers-burning

A little deforestation goes a long way

In 2012, Brazil passed a new version of its forest management code that, in its most stringent areas, requires landowners to retain 80% of the original forest cover. This law has had an impact in reducing the overall rate of deforestation, although the trends have been unclear in many areas.

Even though this standard was established, so far no one has actually tested how much disturbance happens to a forest when 20% of the tree cover is removed. A new study from a huge team of scientists led by researchers at the University of Lancaster tested the effectiveness of this standard by counting the number of species present in a huge database of undisturbed, partially disturbed, and heavily disturbed forests.

Overall, they found that in terms of protecting biodiversity in the rainforest, the 80% standard still caused major drops in biodiversity. Even forests that only saw 20% disturbance still saw a loss of 40 to 60% of the preexisting biodiversity.

It’s clear from photos like this one of the Rio Tinto river that areas at the south, heavily disturbed areas will suffer almost total losses in original biodiversity, but before now the effect of a single road or a small disturbance wasn’t known. This study implies that although the 80% standard is an improvement, if humans want to preserve biodiversity in areas like the Amazon Rainforest, there is no substitute for truly leaving areas as untouched wilderness.

-JBB

Image credit: NASA/Aqua/MODIS https://flic.kr/p/aahLdS

Original paper: http://go.nature.com/29TC8N8

Reference on the law: http://bit.ly/1T9B8RJ

DEFORESTATION: BORDERLINE DESTRUCTIVE

Taking a flight across the Hispanola island border of Haiti, at left to the west, and the Dominican Republic, at right to the east, can yield a startling observation - a sheer contrast between a barren, deforested land and a thriving forest ecosystem.

Haiti has long been stripped of its once flourishing treetop cover. Demands for charcoal and other economic benefits in early 20th century Haiti prompted the deforestation of its land. Haiti's environment remains one of the most devastated in the modern world. Only 30% of the land is arable, and a plan to eradicate poverty recoiled to be a chief cause of poverty in Haiti.

One of the most detrimental results of this deforestation lies in erosion and soil loss. Haiti's forests were key in protecting against erosion, and following their disappearance, soil loss became widespread in Haiti. Karst topography is very important in filtering infectious agents in the water. Because Haiti is mainly composed of karst topography, a majority of its water is far less safe to drink, especially in a third-world nation lacking water purification. Haiti's tropical forests used to act as a climate controller, absorbing rain. Oppositely, rain storms are now magnified into massive storms ravaging the barren landscape.

The Dominican Republic's ecosystem, as pictured, is clearly quite different. It is described as a "mass of entangled foliage", with forests and other vegetation constructing a continuous canopy of green. Wildlife is quite diverse, and the Dominican Republic faces little of the deforestation problems that Haiti encounters today.

--Sam J.

Photo credit: Harm de Blij, Michigan State University

References:

http://www.jstor.org/stable/208737

http://www.nytimes.com/2012/10/30/world/americas/yet-another-blow-to-haiti-from-hurricane-sandy.html?_r=0

http://www1.american.edu/ted/ice/haitidef.htm

http://www.gvsu.edu/cms3/assets/53940C9B-B252-5B69-626B48622A4C1002/presentations/deforestation_and_charcoal_production_in_haiti12-20-12.pdf

http://www.dtic.mil/cgi-bin/GetTRDoc?AD=ADA528274

Source

Earth's Trees

A new study authored by Thomas Crowther of Yale University has estimated that there are three trillion trees on earth; far surpassing the previous estimate of 400 billion trees. Crowther and his team used ground survey data (such as National forest inventories) and satellite pictures to produce a model that predicted the number. This model generated 1.39 trillion trees in the tropics, 0.61 trillion in temperate areas and 0.74 trillion in boreal forests. Using this data they were also able to estimate that in the past 11,000 years, humans have removed 3 trillion trees. Currently, the rate of removal (for timber, land use conversion and agriculture, etc.) is estimated to be 15 billion trees per year, with 5 billion replanted each year.

~SA

Image: http://bit.ly/1EJVE7z by Scott Wylie Paper: http://bit.ly/1EJVMUJ

The Ancient Amazon was once a thriving metropolis

When one thinks of the lush Amazon rainforest, an ancient flourishing metropolis probably isn’t the first thing that comes to mind. The Amazon is the Earth’s largest rainforest, spanning an area of 6.7 million square kilometers across nine countries, and is home to one-tenth of world’s known species. Trying to survive the Amazon, let alone attempting to build a functioning society, is a pretty grim task, and scientists believed that the Amazon had always been an untouched wilderness before the modern era of deforestation. Yet archaeologists have found evidence that complex societies had existed in the Amazon for thousands of years, and that the wilds of the Amazon only reclaimed these settlements in the past few hundred years.

Researchers studied plant and soil samples, and simulated models of the Amazonian landscape to estimate population sizes and language distributions. They found that the Amazon’s “dark earths” — organic-rich soils that formed from the remains of fires, farming, and human waste — first appeared in the Amazon 6,000 years ago. By the end of the 15th century, the dark earths had expanded enough to support populations of over 8 million. But when the European colonists arrived in the Americas with plans of conquest, they also brought along a host of diseases that killed more than 50 percent of the Native American communities. The Amazonian peoples were eventually decimated, allowing Mother Nature to consume the vestiges of their civilizations.

Interestingly enough, the Amazonian peoples had successfully built their societies without clearing areas of forest for crop pastures. What researchers hope to figure out next is something that we are still trying to learn today — how the Native Amazonians were able to build complex societies without wiping out their rainforest environment.

-DC

Photo credit: http://bit.ly/1GShWhB

More reading: http://bit.ly/1U1fIWF http://bit.ly/1S5fdgT

How to survive the Amazon: http://usat.ly/1hPOz9l

Amazon Deforestation Surges

The Amazon Basin is sometimes called the “lungs of the Earth”. It contains a huge amount of vegetation, about ½ of the world’s rainforest, and produces 20% of the atmosphere’s oxygen by some estimates.

Land has been harvested from the Amazon rainforest for decades. Starting in the 1960s, inhabitants in the area began clearing land for agriculture, particularly for soybean crops and for raising cattle.

Deforestation reached a peak in the 1990s, with an area the size of the country of Spain permanently cleared in that decade. But since then, it seemed like progress at preserving the landscape was happening. Helped by new regulations and cooperation of the local governments, the yearly area deforested in the Amazon dropped by 77% between 2004 and 2011.

Unfortunately, that trend is rapidly reversing. 2013 saw an increase in deforested area of 29% over the 2012 total, and the final months of 2014 were even worse. Based on satellite measurements of cleared areas, October of 2014 saw a 467% increase in deforested area compared to October of 2013.

In previous decades, deforestation was driven by expansion of larger farms. As government policies changed, it was possible to limit the forest clearing because it was driven by a few large sources. However, in recent years that pattern has changed. Small landholders expanding their territory drove most of this increase in deforestation and managing huge numbers of small farmers is a much greater challenge than managing a few large tracts of land.

When land is cleared in the Amazon, it is almost impossible to bring the forest back. The soils are extremely thin and weak, only held together by the trees. Once the trees are gone, the soils are often lost, forcing the landholders to clear even more land just to keep the farms going. Beyond that, the trees also impact the local climate; trees bring water into the air and help regulate temperatures, so once they’re gone it can even drive more extreme local weather conditions.

This massive surge in deforestation is an ominous sign for the lungs of the world.

-JBB

Image credit: Daniele Gidsicki https://flic.kr/p/3ePvJ3

Read more: http://bit.ly/1EifqUN http://www.pnas.org/content/111/43/15591.abstract http://www.bbc.com/future/story/20130226-amazon-lungs-of-the-planet http://bit.ly/1NevCKV

Brazil drought threatens the future of its huge cities We reported a few months ago on the increasing water crisis and societal tensions in southern Brazil due to the failure of the rainy season last year causing the worst drought in at least 80 years (see http://on.fb.me/1BQUJPY). Particularly affected is the megalopolis of Sao Paolo (20 million dwellers), the continent's economic capital, whose reservoirs now stand at 5%, despite being halfway through this year's (so far) very weak rainy season.  Since we last wrote the situation has worsened, and many new areas, including that of the continent's other megalopolis (Rio de Janeiro, whose 4 main reservoirs now stand at 1% capacity) are now affected. Taps are running dry and blackouts are occurring due to the lack of water to run hydroelectric power and the high demand for air conditioning as temperatures warm year by year, resulting in rolling power cuts that are affecting communities and businesses alike in many towns and cities. Electricity has been bought from neighbouring Argentina, but they tend to have power problems of their own at this time of year (Buenos Aires endured 2 weeks rolling blackout last summer at 40 Celsius, I was there, it wasn't fun). The effects are serious, much more than the large worldwide increase in coffee prices that looms next year or the low sugar cane crop (used to fuel cars and make cachassa amongst others). While Sao Paolo has managed to cut water use by a quarter, the water authority has asked the people to help prepare for the worst, whatever that turns out to be. The prospect of such a huge city actually running out of water is a scary one, and a leap into the unknown for modern humanity. Full scale rationing is about to be introduced (and already has been in 93 cities around the country, down to 3 days a week in some), and protests are already spreading before its enactment. Much of last year's unrest was also partly fuelled by the daily frustrations of power cuts and low water availability. The poor are always worst hit. Many live in favellas and lose water when the pressure is turned down every evening since these are sited on the hills. Some in Rio haven't had running water since before Christmas. The authorities are overwhelmed. Years of underinvestment in infrastructure are also coming home to roost, and urgent leak plugging measures are being taken, but too late. The needs of the growing middle class have also stressed the electrical and water systems to the limit, showing the dependence on sound stewardship of our planet of the modernisation theory of progress. As well all know, for the world's population to have a realistic aspiration to live like the western middle class, we would need several planets rather than one.  The principal culprit seems to be the extensive deforestation of the Amazon basin coming to haunt its distant creators. The rains that watered the south came from evapotranspiration from the rainforest, transferring Amazon basin water to the south of the country as the moist air drifted south with the breeze. Now that the extent of the forest has shrunk, so has the evaporation. We recently shared an image from space of pretty but deadly deforestation patterns in the rainforest at http://tmblr.co/Zyv2Js1ai0tRB. It's the sort of simple feedback loop that Gaia theory is made of. A secondary cause is the heat island effect of such huge cities preventing cloud formation. Let us hope that some rain comes soon, before the situation changes from serious to crisis proportions.  Loz Image credit: A view of drought-stricken Rio Jacarei in southeastern Brazil, where water levels were at the lowest level since 1974. Luis Moura http://www.theguardian.com/world/2015/jan/23/brazil-worst-drought-history http://www.theguardian.com/world/2015/jan/17/sao-paulos-water-supply-in-critical-condition-as-drought-bites

Trees of death This photo by Astronaut Alexander Gerst taken from the ISS captures trees growing in a part of the Amazon rainforest, but the type of tree is quite ironic. These are trees of deforestation.  In this rainforest, deforestation tends to follow the roads. It begins with construction of a road, sometimes legal sometimes not, that basically serves as a trunk. From there, other roads are cut into the forest and farms are established along the roads. Those farms can be active for a few years, but the combination of nutrient-depleted soils and heavy rains that wash away soil force the farms to continually expand, cutting away at the forest around it. This is particularly worth highlighting now, since we just noted that 2015 is considered the International Year of Soils and soil quality permeates this entire issue (http://fb.me/1wPzsUhIz)  Viewed from above, this clearing basically starts as a trunk that grows branches and leaves that grow outward on the branches with time, except that the trunk, branches, and leaves are areas of the forest that have been clear-cut. -JBB Image credit: Astro Alex, ESA/NASA https://flic.kr/p/pBs4Ks Read more: http://1.usa.gov/1xdVF9g

The Amazon rainforest and the word “deforestation” have gone hand in hand for many years. But today, I want you to add the word “improvement” – because things are getting better. The destruction of the rainforest is now at its lowest rate since monitoring regimes began in Brazil 24 years ago.  Although 4,600 square kilometres of forest were still lost between July 2011 and July 2012, this was a 27% reduction on the previous 12 months. In the Mato Grosso region the reduction was 31% and in Para it was 44%.  Overall, deforestation rates in the Amazon have been decreasing since 2004.  As deforestation releases large quantities of CO2, Brazil has been one of the largest greenhouse gas emitters in the world. Any reduction to this is very encouraging news and shows just how much is possible when stringent environmental policy is enforced.  The Brazilian government hopes to reduce deforestation to 3,925 square kilometres by 2020; this is now looking achievable.  Things can only get better.  -Jean  For more information see here: http://www.treehugger.com/natural-sciences/amazon-deforestation-rate-lowest-record.html Infograph found here: http://www.pachamama.org/blog/deforestation-in-brazilian-amazon-at-lowest-level-in-24-years

Amazon deforestation linked to terrible drought A new report from Brazil's space institute suggests that the rainforest may be damaged to the point where its crucial role in regulating the regional climate is breaking down. Southern Brazil is surviving a terrible drought at the moment that has now been linked to this process, and water scarcity is causing rising social and economic problems which we have already reported on at http://tinyurl.com/pehu72r and http://tinyurl.com/qylabjz. The destruction of the forest by logging and burning has picked up in recent months after a slowdown earlier in the year, and as it continues apace effects on the regional climate and more extreme weather events are likely to worsen. The study was a review paper drawing on over 200 other papers, summarising the current state of knowledge on the inter relationship between forests and climate. The study claims that problems are more serious than had been realised up until now, partly due to the fragmentation of knowledge caused by the current trend towards overspecialisation in science. With the pressure to publish and the need to keep up with one's field, finding time to poke around outside it in a way that makes for good synergies is increasingly difficult. Indeed, last year James Lovelock admitted that he couldn't have done what he did in the current academic environment. General papers such as this provide a useful overview tying together threads from many separate disciplines.  The report suggests that the inbalance of the ecosystem is leaving the “vegetation-climate equilibrium teetering on the brink of the abyss” , which if a tipping point is reached (almost impossible to predict in advance) could turn the Amazon rainforest into a much direr semi desertic savannah.  The consequences would be dire, as the rainforest channels rain down rivers and recycles moisture by evaporation and rainfall, spreading the rainfall that lands in the hills of Peru and Venezuela throughout densely populated Brazil. As the forest is destroyed, the transpiration of the trees goes down, meaning less moisture in the air to form rain giving clouds. Studies predicted this outcome over 20 years back, and now the chickens seem to be coming in to roost, as modelling turns into reality before our eyes. The authors call for an all out effort to halt deforestation and start planting before the consequences become irreversible. The drought is still ongoing and Sao Paolo's reservoir storage is now down to 5% capacity. Loz Image credit: Eric Pheterson

Madagascar Madagascar has long held a fascination for many due to the stunning natural beauty and the fascinating creatures that live there. But now the things that make Madagascar unique are under threat, and why? Land clearing and industrialisation.  A report released by the International Union for the Conservation of Nature (Link Below) has added 83% of Madagascar’s 192 varieties of Palm tree to the threatened species list. This number is horrifying, not just because this a time when the dynamics of our planet are changing, and more greenhouse gases in our atmosphere are resulting in an increased rate of climate change, but because of all of those wonderful animals that rely on the Madagascan forest.  The majority of Madagascan Palms grown in the Madagascan rainforest, which has already shrunk to just 1% of its original size. This is worrying, as over 50% of the Flora and Fauna of Madagascar exists nowhere else on Earth due to the 165 million year isolation of the Island starting with the break up of Gondwana. And all of this wonderful biodiversity is falling prey from the “Domino Effect”. And it’s not just the biodiversity at risk from agriculture and land clearance, many Madagascan people rely on the trees to produce the raw materials for houses, utensils and crafts and also produce food, drinks and medicine. For more information head to the links below; -LL Links; http://www.iucn.org/news_homepage/?11273%2FMadagascars-palms-near-extinction http://www.wildmadagascar.com/?N1_ID=167&N2_ID=222 http://www.bbc.com/news/world-africa-19985536 http://www.savethelemur.org/ Image hosted here;http://bit.ly/PDz0nV

An interactive map has now been made available revealing the levels of global deforestation between the years of 2000 and 2012. The map has been created by analysing 654,178 Landsat images. The program looks at both forest loss and forest gain. The calculations are accurate down to about 30 meters providing enough detail to provide useful local information while still covering the whole globe. This screenshot shows forest cover loss between 2002 and 2012. Red indicates loss and black, no loss. Have a go, and see how your own country stands in relation to deforestation:http://earthenginepartners.appspot.com/science-2013-global-forest