Arxiu d'etiquetes: war

Nature in times of war

The actual world  is in turmoil. News related to terrorism, drug trafficking, coups d’état,  refugees crisis or the numerous wars still present flood our screens day after day. And, in a completely understandable bias, the focus is almost exclusively on the people and countries involved. But (and it’s something I ask every time I watch the news) what happens to nature in these regions punished by violence? In this entry we review the most important armed conflicts nowadays and their consequences for the nature surrounding them.


Any human action has repercussions on natural life, and even more wars, intrinsically destructive. A series of damages on the wildlife are associated with them such as deforestation, soil degradation, pollution or hunting, among many others. The first time we really became aware of the great impact of the wars on nature was in the Vietnam War. The US army, in its fight against an invisible enemy, threw more than 75 million liters of herbicides into the jungles, in order to defoliate the trees to find their enemies. However, despite partially achieving its objective (we all know how that war ended) nature was seriously damaged. A study carried out in Vietnam in the mid-1980s found that there were only 24 birds and 5 mammals in an area where there were previously between 145 and 170 birds and between 30 and 55 mammals.

A Huey helicopter from the US military overhangs the jungles of Vietnam while ‘bathing’ them with orange agent. Agent Orange was a potent herbicide and defoliant used by the United States during the war to make more visible enemies hidden in the jungle. A single plane could defoliate tens of hectares in a single flight. The US government spent $ 60 million a year on Agent Orange. Source: Zmescience.

Other wars, such as the Civil War in Rwanda, apart from causing more than 500,000 deads and displacing more than 2 million of people, left the nature of the country in a state of absolute crisis. In the Akagera National Park, one of the most emblematic environments in the country, deforestation wreaked havoc: 200,000 of the 300,000 hectares of forest were lost in just 3 years, as well as 90% of large mammals.

But what is happening today? How are the wars of today affecting the survival of nature? Here we review the most important current conflicts and their difficult coexistence with the wildlife of the region.

Israeli-Palestinian Conflict (1948-present)

Although the last war between Israel and Palestine began in 2005, violence between the two countries has been present since the creation of the state of Israel. Thousands of people have been dead for decades, and millions have been displaced against their will. And, of course, nature has not come out unscathed.

One of the most famous cases occurred in 2006. The Israeli army bombarded two oil tanks near a power station in Jieh, Lebanon (where a terrorist group called Hezbollah was emplaced) causing a spill of 10,0000 and 15,000 cubic meters of oil in the Mediterranean sea. This black tide spread along 90 km of the coast of Lebanon, carrying the death with it. In addition, this phenomenon severely affected the habitat of the green turtle (Chelonia mydas) in one of the last well-preserved places that this species still had in the Mediterranean basis.

The bombing of two oil tanks by the Israeli army left 80 km of the Lebanese coast as can be seen in the image. In 2014, the United Nations Assembly urged Israel to compensate Lebanon with $ 856.4 million for this environmental catastrophe. Source: hispantv.

However, in early 2016, images that would call even more international attention came to light: dozens of animals from the Gaza zoo appeared completely mummified after suffering a terrible agony and starving. It happened twice since the zoo opened in 2007, but the strongest famine took place in 2014, following a conflict between Israel and Hamas’s Palestinian forces. It is estimated that about 80 animals died because of famine, including crocodiles, tigers, baboons or porcupines. When rescue services were able to reach the zoo, only 15 animals remained alive, many of them with severe symptoms of malnutrition.

The Gaza zoo became the World’s Worst Zoo due to the shocking images of mummified bodies as a result of the famine that caused the war. According to Abu Diab Oweida, the owner of the zoo, the bodies were mummified so that everyone could see that even the animals were affected by the war. Source: Dailymail.
The continuous bombing in the Gaza Strip cause numerous casualties, such as those of the horses in the picture. Unfortunately, the end of the conflict is still so far. Source: helpinganimalsingaza.

Second Congo War (1998-2003)

This war, also known as the Great War of Africa or the African World War, has caused the death of more than 5 million people since then, which has given it the dubious honor of being the deadliest armed conflict since The Second World War. Although the war officially ended in 2003 and there is an elected government since 2006, the Democratic Republic of the Congo lives in a state of instability typical of a country at war.

The guerrillas use the country’s many natural resources to obtain money so they can continue the war. And ivory is the most precious commodity, the one that produces the most benefits. That is why African elephant populations (Loxodonta africana) have been reduced by 90% since the beginning of the conflicts. Something worse has occurred to the northern white rhinoceros (Ceratotherium simum cottoni) a subspecies of the white rhinoceros. Its last specimens, 2 males and 2 females living in the Garamba National Park, are believed to have died between 2006 and 2008 at the hands of the guerrillas, causing the extinction of this subspecies.

The mountain gorilla (Gorilla beringei beringei), with an estimated population of  only 700 individuals, lives almost exclusively in the Virunga Mountains, a territory shared by the Democratic Republic of Congo, Rwanda and Uganda. In the picture, a mountain gorilla killed by unknown causes in 2007. It is believed that the rangers were involved in his death. Source: The Guardian.

Bushmeat, or the food coming from wild animals, is another major problem stemming from the numerous military conflicts in the country. In the wake of extreme poverty, many villagers have been forced to hunt to survive. And the primates has been one of the most harmed groups. The populations of the great primates, once counted by millions, have been drastically reduced. It is believed that there are only 200,000 lowland gorillas, 100,000 chimpanzees and 10,000 bonobos in freedom.

Bonobos (Pan paniscus) are our closest relatives, and one of the most threatened animals in the Congo. It is endemic to this country, but is being heavily hunted for food and, more recently, to serve as a delicacy to the Asian market. Specimens such as it appears in the image can easily be found in the markets of Kinshasa and Brazzaville. Source. National Geographic.

Syrian Civil War (2011-present)

Undoubtedly, the most famous war at the moment. This conflict has killed more than 500,000 people and has caused one of the most important humanitarian crises of our time: it is estimated that there are more than 10 million of refugees because of the war. Those who have remained in Syria, have been displaced from the interior to the coastal zone, becoming a great threat to the forests of the region. According to Aroub Almasri, a Syrian government environmentalist, most people need food, electricity and fuel to cook and warm up, which has lead to clear the area’s forests, mostly in protected areas. Apart from the severe impact of deforestation, there are also a large number of fires that have been spreading throughout the region in recent times. A particularly affected area is the Fronlok forest on the border with Turkey. In these mountains the degree of endemism is high, and many species are at a serious risk of disappearing from the area, especially a type of oak, Quercus cerris, native to the region and which would begin to be threatened.

Due to the fragmentation of the habitat, it is believed that an iconic species of the Mediterranean zone and classified as critically endangered by IUCN has become extinct in Syria. It is the bald ibis (Geronticus eremita), a bird of which only 500 individuals remain and is present only in three countries: Morocco, Turkey and Syria. In spite of Syria‘s enormous effort to maintain a stable population in its territory, the war wiped out the last individuals of this species in the region. Only one individual of the species remains, a female named Zenobia, who was seen for the last time in Palmyra before ISIS troops entered the city.

It seems that the numerous efforts made by the Syrian government in the early years of the twenty-first century have been insufficient to save this iconic species from extinction. Formerly present in large parts of Europe (from Austria to the Iberian Peninsula) the bald ibis has the most important populations in Morocco, its last redoubt in the natural state. Source: New Scientist.

Second Libyan Civil War (2014-present)

After the first Libyan civil war, which ended with the fall of Colonel Gaddafi, the country entered into a spiral of violence sponsored by the numerous armed groups that control the country. The importation of meat from abroad has stopped, and the owners of sheep, goats and camels keep their animals as if they were gold because of shortages. Because of this, armed groups are heading to the south of the country, where anarchy prevails and there are a lot of wild animals to take advantage of.

One of the most harmed species has been the rhim gazelle (Gazella leptoceros), classified as threatened by IUCN and with its populations in decline. Ten years ago the population did not exceed several hundred individuals, and it is believed that today the situation is much worse.

Rhim gazelle is native to North Africa, where there are less than 2,500 individuals. The militias use their meat to feed or sell it in the Libyan market, where it is scarce. Source: Creative Commons.

But the gazelles are not the only ones harmed by the banditry and impunity reigning in Libya. Large numbers of migratory birds, which have to cross the African country on their way to Europe, are slaughtered by hunters. In addition, the oases that they use to rest are being opened by the hunters, which causes that hundreds of cranes, ducks, herons and flamingos are annihilated without anyone can do anything.

In addition, the effect of the Libyan war on nature does not remain within its borders. In 2015, weapons from Libya were found near elephant corpses in Mali, a heavily threatened elephant subspecies. It is believed that the ivory of the Mali elephants is serving to finance the Libyan militias.

A slaughtered elephant is seen in Bambara-Maoude
Mali’s elephants are one of the only two populations of elephants living in the desert. The last air census (2007) revealed the presence of only 350 individuals in the country. In 2015, 80 elephant were hunted, so the forecasts are not at all flattering: scientists believe that the population will die out in 3 years. Source: Reuters.

The Colombian government against the FARC and other guerrillas (1964-2016)

Despite the peace agreement reached few months ago between the Colombian government and the FARC, both social and environmental wounds will take a long time to be closed. For a long time the militias have been financed largely from the money generated by illegal cocaine crops. Placed deep in the Colombian jungle, thousands of hectares of pristine forest have been cleared for the construction of laboratories and coca plantations. In addition, in an attempt to stop this type of illegal crops, the government fumigated extensive forest areas with glyphosate, a herbicide that, despite being considered harmless, caused the death of birds, small mammals and insects, what in turn left without sustenance the people who live on hunt. Another added problem is that illicit crops have spread to protected areas. Thus, according to a report by the National Parks of Colombia, FARC were present in 37 protected areas of the country, and 3791 hectares of coca plantations were also detected in there.

However, the illicit activity that most threatens Colombia’s nature is illegal mining, one of the most lucrative activities for armed groups. Not for less, since while 1 kg of coca is sold at about 4.3 million pesos, 1kg of gold is sold at 85 million pesos, about 20 times more. For this reason, large areas of jungle have been destroyed by backhoes to open gold (60%), coltan (25%), charcoal (10%) and tungsten (5%) mines. Deforestation resulting from illegal mining reaches unimaginable numbers: between 1990 and 2010, an average of 310,349 hectares of forest per year were deforested, that is, 6206.000 hectares in all that time, or what is the same, 5.4% of the Colombian surface.

Mercury and cyanide, highly contaminating metals, are used for the extraction of gold. It is estimated that about 200 tons of mercury go to Colombian rivers each year. This has caused, at least, the contamination oh 90 rivers, affecting the local fauna and flora. Source: Semana.

Finally, FARC actions against oil extraction have caused serious oil spills in areas of high environmental value. This is the case, for example, of the 492-liter oil spill in Puerto Asis, Putumayo, in June 2015. The FARC intercepted a convoy containing tanks with oil and spilled them, affecting 9 wetlands and spreading oil along the Putumayo River.

In 2013, the FARC’s systematic attacks against the oil industry accounted for 132 only in the province of Putumayo. Hydrocarbons contaminate the soil and remain there for years. In water, oil, due to its oxygen consumption, creates anoxic conditions that causes the death of fish. Source: elcolombiano.

War in Afghanistan (2001-2014)

Either the last war and the previous one had a strong impact on the region’s wildlife. It is estimated that between 1990 and 2007, more than one-third of Afghanistan’s forests were cleared, either by refugees to use wood for cooking, fuel or construction, or by logging industries, which cut down the forests of the region with impunity.

Nevertheless, the news are more optimistic than would be expected of a country plunged into war for decades. Between 2006 and 2009, the first censuses since the 1970s were carried out in the province of Nuritán, with the help of trap cameras, the study of faeces and the realization of transects. The results were encouraging: 18 black bears, 280 porcupines and many red foxes, gray wolves, golden jackals, wildcats, palm civets and rhesus macaques were observed, and even the elusive snow leopard (Panthera uncia), concretely 3 distinct individuals.

Photo-trapping cameras captured images of the elusive snow leopard in the rugged Afghan mountains. With no doubt, they are encouraging news for its conservation. Source: James Nava.

However, there are still threats for Afghan wildlife. The large number of bombs thrown during the years made a dent in the abundance of migratory birds. Many birds died directly from the impact of the bombs or poisoned when they came into contact with contaminated water. Others, however, varied their rute due to the bombing and no longer cross the country. This is the case of the Siberian crane (Grus leucogeranus), a species critically endangered by IUCN that has not been seen in Afghanistan since 1999. In addition, due to the war and the incipient Afghan economy, hundreds of hunters Are forced to catch live birds for subsequent smuggling into rich Arab countries. This has led to the fact that, in some regions of Afghanistan, migratory bird watching has declined by 85% since the start of the war.

According to the Afghanistan Environmental Protection director, every year around 5000 birds are hunted for contraband, especially in the regions of Syed Khel and Kohistan. Many of the Houwa bustards (Chlamydotes undulata) and different types of hawks are sent to rich Gulf countries to serve as pets. In the picture, Afghan hunters near their rudimentary cages. Source: focusingonwildlife.

Korean Conflict (1950-present)

The Korean Demilitarized Zone is the proof that even something as tragic as a war can bring positive consequences. In 1953, following the peace agreement by both countries, the Korean Demilitarized Zone, a strip of land 4 km wide and 250 km long that separates both countries, was created. The area, which has a strong military presence of about 2 million soldiers, has remained virtually unchanged and sparsely populated since then.

The Demilitarized Zone of Korea, or DMZ, separates both countries thanks to a buffer zone 4 km wide. In this place, the leaders of both countries usually hold the infrequent and tense meetings. Source: Creative Commons.

The area is characterized by a great topographic richness and high variety of ecosystems, which allows it to contain a great diversity. Some scientific expeditions have documented more than 1,100 species of plants, 80 species of fish, 50 of mammals and hundreds of birds. In addition, it is a frequent stop for many species of migratory birds that head towards Mongolia, the Philippines or Australia.

The area has a great diversity of flora and fauna. Deer, bears, wild boars and large numbers of birds inhabit the territory. It is even believed that it could contain some individuals of the siberian tiger, habitual inhabitant of the zone before the Japanese occupation of Korea. Source: BBC.

Recently, thanks to improved relations between the two countries, the area can be visited for only about 43 euros. In addition, due to its exceptional conservation status and high diversity, some campaigns are under way to turn the area into a protected area. One of these campaigns, the DMZ Forum, proposes to declare the area as World Heritage Site and World Park for Peace, in order to be able to protect it from a possible urban development on the day that peace between the two countries is reached.

The area has received numerous supports to convert it into a nature reserve in order to protect it from a possible future exploitation. Among the personalities who have supported the plan are the former US President Bill Clinton and the CNN founder Ted Turner. Source: BBC.


DeWeerdt, Sarah (January 2008). “War and the Environment”. World Wide Watch. 21
King, Jessie (8 July 2006). “Vietnamese wildlife still paying a high price for chemical warfare”. The Independent.
Kanyamibwa S (1998). Impact of war on conservation: Rwandan environment and wildlife in agony. Biodiversity and Conservation, 7: 1399-1406.
Cover picture: Earth in transition.


Metal hyperaccumulation in plants

During million years the evolution leaded plants to develop different strategies to defence from natural enemies, giving rise to an evolutionary weaponry war in which the survival of ones and others depends into the ability to beat the other’s adaptations. It is in that scenario where the high-level accumulation of heavy metals in plants plays an important role.


Boyd (2012) commented that plant defences can be grouped in different categories:

  • mechanic: thorns, coverage, etc.
  • chemical: different organic and inorganic components.
  • visual: crypsis and mimicry .
  • behavioural: related with phenology’s modification.
  • and associative: symbiosis with other organisms, such is the case of the genus Cecropia, which has stablished a symbiotic relationship with ants of the genus Azteca, who protects these plants – to know more: Plants and animals can also live in marriage-.
Mechanic defence with thorns (Author: Karyn Christner, Flickr, CC).

It is known that chemical defence is ubiquitous, and thus, a lot of interactions among organisms can be explained for this reason. In this sense, some plants contains high levels of certain chemical elements, frequently metals or metallic components, which plays an important role in the defence, these plants are the heavy metal hyperaccumulating plants.

Heavy metal hyperaccumulating plants and their main characteristics

This plants belong to several families, thus hyperaccumulation is an independent acquisition occurring different times during the evolution. In all cases, hyperaccumulation allowed the ability to grow soils with high levels of heavy metals and to accumulate extraordinary amounts of heavy metals in aerial organs. It is known that the concentration of these chemical elements in hyperaccumulating plants can be 100 – 1000 times higher than in non-hypperaccumulating plants.

Generally, chemistry describes heavy metal as transition metals with atomic mass higher than 20 and with a relative density around 5.  But, from a biological point of view, heavy metals or metalloids are elements which can be toxic in a low concentration. Even though, hyperaccumulating plants has become tolerant, i.e., they hypperacumulate this heavy metals without presenting phytotoxic effects (damage in plant tissues due toxicity).

In this sense, there are three main characteristics typically present in all hyperaccumulating plants:

  • Increased absorption rate of heavy metals.
  • Roots that perform translocation more quickly.
  • Great ability to detoxify and accumulate heavy metals in sheets.

Thus, hyperaccumulating plants are prepared to assimilate, translocate and accumulate high-levels of heavy metals in vacuoles or cellular wall. In part, it is due to the overexpression of genes codifying for membrane transporters.

The threshold values that allow to differentiate a hyperaccumulating plant from a non-hyperaccumulating one are related to the specific phytotoxicity of each heavy metal. According to this criterion, hyperaccumulating plants are plants that when grown on natural soils accumulate in the aerial parts (in grams of dry weight):

  • > 10 mg·g-1 (1%) of Mn or Zn,
  • > 1 mg·g-1 (0,1%) of As, Co, Cr, Cu, Ni, Pb, Sb, Se or Ti
  • or > 0,1 mg·g-1 (0,01%) of Cd.
Minuartia verna, copper hyperacumulating plant (Autor: Candiru, Flickr, CC).


Till the moment, several hypothesis has been proposed to explain why certain plants can hyperaccumulate heavy metals:

  • Tolerance and presence of metals in soils.
  • Resistance to drought.
  • Interference with other neighbouring plants.
  • Defence against natural enemies.

The most supported hypothesis is “Elemental defence”, which indicates that certain heavy metals could have a defensive role against natural enemies, such as herbivores and pathogens. So, in the case these organisms consume plants, they should present toxic effects, which would lead them to die or at least to reduce the intake of this plant in future. Even though heavy metals can act through their toxicity, this does not guarantee plants will not be damaged or attacked before the natural enemy is affected by them. For this reason, it is still necessary a more effective defence which allow to avoid the attack.

In contrast, according to a more modern hypothesis, the “Joint effects”, heavy metals could act along with other defensive organic components giving rise to a higher global defence. The advantages of inorganic elements, including heavy metals, are that they are not synthetized by plants, they are absorbed directly from the soil and thus a lower energetic cost is invested in defence, and also they cannot be biodegraded. Even though, some natural enemies can even avoid heavy metal effects by performing the chelation, i.e., using chelators (substances capable of binding with heavy metals to reduce their toxicity) or accumulating them in organs where their activity would be reduced. This modern hypothesis would justify the simultaneous presence of several heavy metals and defensive organic components in the same plant, with the aim to get a higher defence able to affect distinct natural enemies, which would be expected to do not be able to tolerate different element toxicity.

Thlaspi caerulescens, zinc hyperaccumulating plant (Autor: Randi Hausken, Flickr, CC).

On the other hand, it has been shown that certain herbivores have the ability to avoid the intake of plants with high levels of heavy metals, doing what is called “taste for metals“. Although this is known to occur, the exact mechanism of this alert and avoidance process is still uncertain.

Solanum nigrum, cadmium hyperaccumulating plant (Autor: John Tann, Flickr, CC).

Additionaly, even tough heavy metal concentration in plant are really high, some herbivores manage to surpass this defense by being tolerant, i.e., their diet allows them to intake high dosis of metals and, thus, consume the plant. This could lead to think some herbivores could become specialist in the intake of hyperaccumulating plants, and, thus, this type of defence would be reduced to organisms with varied diets, which are called generalists. It has been demonstrated to not be true, as generalists herbivores sometimes present a higher preference and tolerance for hyperaccumulating plants than specialist organisms.

For all these reasons, it can be said that evolution is still playing an important role in this wonderful weaponry war.



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