Chronicles of a changing world

Monday, 7 October 2019

Green denialism

A couple of years ago I started a small experiment in a small wasteland in my neighbourhood with the intention of checking whether some of the species I often talk about in this blog (the famous "paleoautochtonous" species) were able to adapt to the climate of central Spain. I also tried to plant some species commonly cultivated in the mediterranean coastline to see if it was true that they were unable to survive the supposedly harsh winters of the iberian "meseta". These experiments have already been the subject of an article on this blog (Primer año plantando árboles) and I often report this on my Facebook page. An initiative that I carry out with the enthusiasm of a beginner (which I am, in fact, despite my age) and from which I hope to learn useful things for the realization of a much more ambitious project. Being all the species that I plant very rare species in Spain or in the center of the Peninsula and being the place chosen an urban open space in which there is an abundance of waste of all kinds, I never had any kind of problem of conscience at the time of carrying out this experiment. Until this weekend, I had not thought that planting trees in an open field could be something harmful or punishable. But, as the following threatening comment shows, it seems that some people are opposed to any kind of experimentation:

Are you aware that you plant species catalogued as invasive in the Atlas of the Ministry and that you advertise, photograph and even document it? That this could constitute an environmental crime? It's an interesting way to explore if you don't stop your efforts to consciously and voluntarily alter ecosystems...

Considering any exotic species as "invasive" or "potentially invasive" is a resource often used by biologists who study invasive species to dissuade us from cultivating any non-autochtonous species. This photograph shows what until now was the only Montezuma Cypress existing in the city of Madrid. "Was", of course, because the one I planted in my neighbourhood for the time being looks very healthy.

This comment, which I am not going to refute here, serves me to talk about the surprising drift that many conservationists seem to have taken towards positions that today seem to me indefensible from a merely scientific point of view. First of all, this drift is due to the vocabulary used by the promoters of invasion biology, which has very little scientific basis and leads to dangerous amalgams of concepts. As you probably know, invasion biology started with the publication in 1958 of Charles Elton's book "The Ecology of Invasions by Animals and Plants". Published in the middle of the Cold War, in a decade marked by the release of films such as The War of the Worlds, the use of a militaristic vocabulary with strongly negative connotations to refer to expanding exotic species has marked the entire history of this discipline. From the very beginning, invasion biology focused exclusively on studying the negative impacts of these species, without any interest whatsoever in the fit that these species could have in the natural processes and in the ecosystems in which they burst, particularly in the series of vegetation. As several studies we have already referred to in another article in this blog (Plantas invasoras de hoy y de ayer) have shown, species that are simply opportunistic or colonizing and that would later be replaced by more demanding species are often referred to as "invasive".

The Barbary sheep only owes to the pressure exerted by the hunters not to have been completely exterminated, after having been included in the national list of exotic species against the criteria issued by the biologists who have studied this species and who know it best.

If invasion biology has remained a marginal specialty in Biology as a whole, it has however decisively influenced the ideology of the ecological movement and vampirized significant public funds. To such an extent that its postulates today have a much greater weight than that of the scientists themselves when it comes to legislating. I have already denounced in this blog the unjustified persecution carried out against the Barbary sheep in the SE of Spain (El porvenir truncado del arrui), ignoring the opinion of the specialists who had studied it (1). The invasion biology is, today in Spain, the closest thing to a religion and whoever dares to contradict them is exposed to being attacked in social networks. The comment I have received this weekend is a good example of it and there are plenty of examples such as the Barbary sheep which show that preconception can outweigh evidence. When I heard that there were brigades dedicated to the complete eradication of eucalyptus trees in Galicia in order to re-establish the native forest, I naturally thought that this was an extraordinary loss of time. It makes no sense to start from scratch in a situation like the present one, in which time is crucial. They could perfectly have organized a small excursion to the "Souto da Retorta" to convince themselves that the presence of eucalyptus is not incompatible with the recovery of the native forest (El bosque imposible).

Where some see a land where eucalyptus has been completely eradicated and ready to be repopulated with autochthonous species I see a treeless land exposed to erosion. Couldn't a few eucalyptus trees have been left to protect the soil and the small oak seedlings? Without such protection, the native forest is likely to take much longer to develop. With an enemy like climate change on our heels, we may someday regret not having been more pragmatic and less purist.... / Picture: La Voz de Galicia

Misunderstood conservationism, carried to its ultimate consequences, prevents us today from reacting quickly to a phenomenon such as climate change. Invasion biology has imposed itself in our country as a kind of monolithic truth that very few people dare to question openly. Those who have risked doing so, like David Theorodopoulos almost 17 years ago (2), received sticks everywhere. That American biologist, however, did nothing more than say that it was ridiculous to differentiate species into indigenous and exotic and dedicate time and money to persecute invasive species. To illustrate this fact, this author often gives as an example in his lectures the numerous and surprising changes observed in the faunas in the last millennia. One such example is the horse, born in North America and disappeared from that continent just 6'000 years ago. Today it is considered an invasive species in North America. The same reasoning applies to many other controversial species, such as the tree of heaven for example, which had a holartic distribution in the Tertiary, before being eliminated from much of its area by quaternary glaciations. The conservationists crushed him by accusing him, among other things, of giving too general examples that did not conform to reality. Climate change, however, is clearly demonstrating that the short-sighted and fixist vision that governs our environmental policies has no future. Why, for example, planting Spanish firs exclusively in their very small current distribution area where this species is in danger of disappearing completely due to climate change?

Will ecologists one day accept the idea that in order to save a species like the Spanish fir, it is necessary to plant it in other mountain ranges farther north? / Photo: View of the Spanish fir from the Jardín BotánicoTorre del Vinagre, in the Sierra de Grazalema. / Autor: Consejería de Medio Ambiente y Ordenación del Territorio

The people involved in listing alien species and deciding whether or not they are invasive have lost sight of the scale of the changes we face. If it is already ridiculous to consider some species exotic on the basis of man-made borders and limits, doing so in a world in which the movements of species and ecosystems promise to reach a much larger scale than most of the studied territories gives an idea of how futile such an effort is. I think it is not useless to remind ourselves once again that climate change is not a future reality. Yesterday I was watching a TV programme and I was very struck by an overprinted message which said that by the end of the century Spain was expected to have a temperature rise of around 3 degrees since pre-industrial times. This is a huge mistake that could let people think that climate change is a matter of the future. The reality is that the average temperature in Spain has already risen 3 degrees since pre-industrial times (E pur si riscalda ) and the 3 degrees to which they refer are actually 3 additional degrees. In other words, by the end of the century the average temperature in many regions in Spain will have risen by at least 6 degrees since pre-industrial times. This is enormous and is roughly equivalent to a rise in vegetation of almost 1000 metres.

Twig of a young specimen of Torreya taxifolia planted in Waynesville, North Carolina (USA), outside its "natural" range, where the species is gradually becoming extinct. Thanks to the efforts of the Torreya Guardians, the species is expanding further north into areas that are much more favorable to it. / Photo: Connie Barlow

The possibility of future changes clearly wasn't in the plans of invasion biologists when they developped the theoretical basis of their "science". They are now incurring in contradictions by not admitting that the ecosystems they are trying to preserve are going to undergo major changes. As a consequence of this, many ecologists are becoming climate change deniers because they do not accept the implications this could have on their work. Most conservationists, however, are aware of the reality of climate change but claim, in an attempt to reconcile their ideas with an undeniable reality, that our ecosystems are resilient and will be perfectly capable of "fitting in" with the effects of climate change. Their main argument is that they did so in the past and will continue to do so in the future, without realizing that the conditions towards which we are moving are absolutely unprecedented (Back to Pliocene ). No matter how much we talk about climate change in the media, I fear that as long as we are not able to convince environmentalists that they are going to have to accept the consequences of climate change and come out of that kind of green denialism that many incur, we will not be able to move forward and start taking really useful measures for the future. Climate change, clearly, is rehabilitating David Theorodopoulos idea that invasion biology is a pseudoscience whose theoretical foundations do not resist the embite of reality...

		(1) Cassinello J. (2018) / Misconception and mismanagement of invasive species: the paradoxical case of an alien ungulate in Spain / Spain Conservation Letters

		(2) David I. Theodoropoulos (2003) / Invasion Biology: Critique of a Pseudoscience / Avvar Books

Monday, 9 September 2019

Paleo-autochtonous species (7): Eucommia

In previous articles, we discovered the thermophilic species that disappeared from the European continent and referred to the existence of different glacial refuges in the south and periphery of the European continent, where a whole series of species that were still present in Europe at the end of the Tertiary era and in the Lower Pleistocene (Quaternary) survived. Unfortunately, not all the species present in Europe at that time had the chance to reach these refuge areas. Many of them disappeared permanently and their close relatives now live in Asia and/or North America. However, a number of these species had a practically holartic or Eurasian distribution area and were fortunate enough to survive outside the European continent. The most famous example is probably the gingko, extremely rare in nature and perhaps saved from possible extinction by the veneration that the Eastern populations professed for this tree.

Less known than ginkgo, but also originally from China, the gutta-percha tree (Eucommia ulmoides) shares a very similar destiny with ginkgo. That species is also, in effect, the only representative of a monotypic family and genus. Like ginkgo, the species is cultivated since time immemorial and its exact origin (natural populations) has not been clearly established. It is a tree with numerous medicinal properties that also has a unique feature among the trees of the cold temperate zones: it secretes latex.

This feature attracted the attention of Westerners at the beginning of the 20th century, who saw in it a possible alternative to rubber of tropical origin. That led to different attempts at acclimatization that were more or less successful. Most of them were soon abandoned when synthetic rubber production developed and it was very difficult to grow this species, from which only male feet were initially obtained. The only country that took the experiment to an advanced stage (production) was the USSR in the 1930s. Some of these experimental plantations still exist (see video below). In other countries, this species is very rare, being able to see only in arboretums and botanical gardens.

Ecology

The gutta-percha tree is capable of living in a wide range of ecological conditions and can be observed in such disparate environments as mixed forests, cleared forests, small forests, low mountains, ridges, valleys, dry ravines and fields (Flora of China). In China, this species has become very rare in the wild and appears dispersed in a relatively large area (see map). Widely cultivated, it has been naturalized in a multitude of places.

Distribution map of Eucommia ulmoides (left) and annual precipitation map of eastern China (right).

As the previous map shows, the species is capable of living in relatively dry areas where rainfall is barely more than 400 mm. One of the most important factors for this species are spring temperatures, Eucommia ulmoides seeds need to germinate at springtime temperatures (April) between 13 and 22 degrees, with the optimal temperature of 18 ° C for germination [1].

Past distribution

The fossils of Eucommia that have been found in Europe in the sediments of the late Pliocene or Quaternary are so similar to the current species that these have usually been attributed to that species. It is likely that other species of this genus were present in earlier times but the current was the only one that managed to reach our days. It managed to survive in southern Europe until the middle Pleistocene and, like many other species that disappeared at that time, it does not seem to have been very good for the intensification and lengthening of the glacial periods in the Upper Pleistocene. It was in the Pliocene and at the beginning of the Pleistocene, a frequent and abundant species in much of Europe and the Iberian Peninsula, where it coexisted with numerous species of deciduous and persistent trees. Given the ecological breadth of this species, it is very likely that it was present in our country in a wide range of ecosystems, both in the Mediterranean and Eurosiberian regions.

The variety of environments in which this species is able to live makes it difficult to know in which types of environments it lived in southern Europe, as the species was probably present at that time in both the Mediterranean and Euro-Siberian regions.


*Eucommia*	Family: Eucommiaceae	Order: Garryales
Trees deciduous, dioecious. Sapwood and bark containing latex. Buds ovoid; scales deciduous. Leaves alternate, spirally arranged, exstipulate, petiolate; leaf blade simple, usually elliptic, sometimes somewhat ovate, obovate, or oblong, containing latex (forming strands if blade is transversely broken and pulled apart), pinnately veined, base rounded or cuneate-rounded, margin densely serrate with gland-tipped teeth, apex abruptly narrowed into an acuminate tip. Flowers axillary, borne near base of current year’s branchlets, very shortly pedicellate, without perianth, wind pollinated. Male flowers clustered; stamens 5–12, linear; filaments very short; anthers basifixed, 4-locular, dehiscing by longitudinal slits; connective slightly prolonged. Female flowers solitary: ovary stipitate, composed of 2 connate carpels, 1-locular, elongate, compressed, glabrous, apex 2-lobed; stigmas 2, decurrent, reflexed-spreading; ovules 2, collateral, anatropous, 1 aborting. Fruit an indehiscent samara, long elliptic to narrowly oblong, compressed, winged around margin; wing gradually narrowed at base into stipe, shortly 2-lobed at apex with sinus stigmatic; pericarp thinly leathery. Seed 1, linear, compressed, rounded at both ends; testa membranous; endosperm copious; embryo erect, large; cotyledons compressed, fleshy. Source: Flora of China

It is a species rarely cultivated in our country. There are, as far as I know, two individulas in the Royal Botanical Garden of Madrid (one of them already quite grown up), another one in Barcelona and ... little else. I have not found, in any case, any reference to other specimens in other regions. It is curious, in any case, that this species has not awakened until now the curiosity of our forestry engineers. Of course nobody was aware until recently that this species was so frequent in our forests at that time. We'll see if the little Eucommias I've planted in my neighborhood go ahead. I have planted them in a small area of my neighborhood in which both the exposure and the edaphic conditions vary a lot, with the idea of seeing if that species is able to naturalize in the Mediterranean region, in places where conditions are somewhat more favorable. If the rabbits do not annihilate them and if nobody steals all the protectors that I have put, then maybe I'll tell you good news a few years from now.

Eucommia ulmoides leaf seen against the light. Real Jardín Botánico de Madrid.

Next year, I will try to plant some of them in an area with a more favourable climate (sub-Mediterranean). Elsewhere, as the short video shot in southern Russia (Sochi region) clearly shows, there is no doubt in my mind that this species is capable of growing almost anywhere. If you are aware of his presence in the area where you live, feel free to leave your testimony in the comments in this article.

One of the small 1-year-old percha-gutta trees I planted in my neighbourhood.

		(1) Wang Y.-F. et al. (2003) / Eucommia (Eucommiaceae), a potential biothermometer for the reconstruction of paleoenvironments / American Journal of Botany, Vol. 90(1), pp. 1–7.

Thursday, 22 August 2019

Back to Pliocene

400 parts per million of CO2 in the atmosphere. That is the level we have reached and surpassed in recent years. The news itself would be merely anecdotal if it were not for the fact that such a level of CO2 had not been reached since... the Pliocene ! And ? many will say. For those who study the climates of the past, however, this figure is a clear warning. The graph I copy below shows the evolution of atmospheric CO2 over the last 800,000 years, as measured in the gas bubbles trapped in Antarctic ice. The same graph also shows the evolution of the mean temperature estimated from the study of oxygen isotopes. What is striking in this graph is the absolute parallelism between these two curves. CO2 and global mean temperature go hand in hand, suggesting that the amount of CO2 in the atmosphere has a considerable influence on the mean temperature of the atmosphere.

Curves of temperature variation (in red) and CO2 variation (blue and green) over the last 800,000 years.

So what does it mean that we have reached a level of 400 ppm of CO2 in the atmosphere? Simply put, temperatures will continue to rise until they reach a new state of equilibrium. Knowing that in the Pliocene the global average temperature was 2 to 3 degrees higher than it is today, this means that even if the release of CO2 into the atmosphere is completely interrupted, temperatures should continue to rise until they reach this equilibrium level. In other words, the famous "maximum" of 2 degrees of warming that Humanity has set itself as a limit not to exceed will probably be reached even if we completely stop consuming hydrocarbons. And yet, on the contrary, the consumption of hydrocarbons has not ceased to increase during the last decades...

Therefore, assuming with honesty that temperatures will not stop rising during the next decades and centuries, I find it interesting to take a look back and examine, from the data of geologists and paleontologists, what our continent was like at that time. If the principle of uniformitarianism developed by James Hutton and Charles Lyell is correct (its application, in any case, is what has allowed geologists and paleontologists to reconstruct the history of our planet), then nothing prevents us from thinking that what we know about the Pliocene can be applied to understand what could happen in the future. In other words, the past is, in some way, a mirror of the future and can help us to understand the great changes we must expect in the future. We will now describe some of the consequences of climate change that the Pliocene study allows us to anticipate.

See level rise

One of the most worrying consequences of climate change, which is often underestimated, is the evolution of sea level. Somehow, we tend to see the large Arctic and Antarctic ice masses as immovable, and we tend to think that the changes affecting those ice masses are very slow. The sudden acceleration of the melting of the Groenlad ice sheet in recent years, that in last years was already melting all over its surface during the summer and the evidence of the existence of large rivers that drain and cross all the ice mass to the rocky substrate, however, have put scientists on notice and the estimates that were made until recently of the rise in sea level from here to the end of the century have suddenly become very short. At the time it was said that the sea would rise by about 30 cm by the end of the century, but today it is not uncommon to hear scientists say that the sea level could rise by as much as 2 metres, which would already have a considerable effect in many areas. In the longer term, if all the ice covering Greenland were to melt, the sea would rise by about 7 metres. And if Antarctica were to start melting, we would then be talking about a sea level rise of up to 35 metres, which is the level it reached in the Middle Pliocene....

This map shows which areas of the SW of our country would be flooded if the sea rose 7 meters / www.floodmap.net

The region of Spain that would suffer most from the effects of the rise of the sea is undoubtedly the Lower Guadalquivir. With a rise of 7 metres in sea level, it would reach the gates of Seville and would form between the Andalusian capital and the coast a great gulf that, in reality, already existed in antiquity but was filled by the terrigenous inputs from the Guadalquivir river. If you look more closely at this map in the floodmap application, you will notice that all the towns of some importance in that area are located on the shores of that great gulf. All of them were coastal populations when they were founded and, if the melting of Greenland and Antarctica does not stop, they will become so again in a not so distant future. The National Park of Doñana would be the great damaged one, losing a good part of its extension but it will certainly be very interesting to see how new and novel ecosystems are formed in this area. Who knows if in the future, with a frankly subtropical climate, an immense mangrove swamp will not develop here. I can already imagine the Romería del Rocío progressing in boats among the roots of the mangroves...

With the rise in sea level and temperatures, the appearance of the lower Guadalquivir could change a lot in the future and look more like this...

Altitude rise of vegetation

Another logical consequence of the increase in the average temperature of the planet is the migration of species towards the poles and the rise in altitude of the vegetation altitudinal zones. To get a small idea of the extent of these changes, the first thing to remember is a basic meteorological fact: the adiabatic gradient of the atmosphere. This gradient is the difference in altitudinal temperature observed in the lower parts of the atmosphere in which we live. In a dry atmosphere, that gradient is approximately 1 degree per 100 meters. In a humid atmosphere, that gradient is approximately 0.57 degrees per 100 meters. Knowing what the increase in temperature has been in the last decades and what the forecasts are for the end of the century, we can have an approximate idea of how much the vegetation altitudinal zones will rise (at least potentially). The first question to be asked is how much the temperatures have already risen. We have already examined this in detail in a previous article (E pur si riscalda) and we then saw that the average temperature in Madrid had already risen by approximately 3 degrees. Taking the two values of the adiabatic gradient, this thus means a potential rise of the vegetation altitudinal zones of between 300 and 546 meters. This does not mean, however, that the ecosystems have already moved up to their corresponding altitudes as the readjustment of vegetation to new climatic conditions is much slower than the evolution of the climate.

Evolution of the average annual temperature in the Retiro station in Madrid (red curve) and the Navacerrada pass (blue curve) according to public data from the AEMET.

The forecasts for the end of the century are a rise of at least 6 degrees in much of the Iberian Peninsula. In other words, that would double the figures I gave you before and the rise of the vegetation floors would then be from 600 to 1092 meters. That is enormous. I have tried to do the exercise of imagining what the Central System would be like at the end of the century and this is what I can imagine:

What I've done is simply to rise the vegetation altitudinal zones. In doing so, however, questions arise about what might happen at some points such as those I have marked with a question mark. What will happen at the foot of the mountain range (2), if the vegetation altitudinal zones rise between 600 and 1000 meters ? Personally I imagine that we would have a thermomediterranean type of vegetation with lentisks, carob trees and mediterranean dwarf palms, which I have represented with a somewhat darker tone. And what will happen at higher altitudes (1) if, as expected, the level of rainfall is maintained? To imagine that the holm oaks will simply rise and occupy these levels does not seem the most likely. Perhaps species such as the cork oak, or more demanding deciduous species such as temperate oaks and maples, will take advantage of this. It is a mystery. However, if questions like these already arise in a place where evolution seems quite predictable, imagine the difficulty of predicting what is going to happen in a region such as the Atlantic seaboard. In many places the climate could become humid subtropical. And do you know what kind of vegetation grows in such places?

Laurisilva on the island of La Palma (Canary Islands) / Fotografía: Gruban / Licencia: CC BY-SA 2.0

Development of novel ecosystems

The rise in temperature and the modification of the rainfall regime could lead in some regions to the emergence of totally new ecosystems, although very similar, morphologically, to those that existed in the past. Will, for example, the temperatures rise enough for the mangroves to return to our coasts? Our coasts, in any case, have an increasingly tropical aspect, thanks to the arrival of an endless number of plants of tropical and subtropical origin whose propagation and development will go more and more throughout the centuries to come. One of the families of plants that contribute greatly to modifying the appearance of our coastal landscapes are the palm trees, which are becoming naturalized in many parts of the Mediterranean coast. The same could also be said of cactus, to which I will one day dedicate a specific article.

The naturalization of different species of palm trees in the Iberian Peninsula gives our landscapes a subtropical air that is a faithful reflection of the changes that are occurring.

As I mentioned before when talking about the rise of the vegetation altitudinal zones, the rise of the winter temperatures will favor in the humid regions the growth of many perennial species that will modify completely the physiognomy of the forests that they colonize. It may seem a distant phenomenon and imagine the "return" to the Peninsula of the species that coexist in the Macaronesian laurel forests may seem like science fiction. It should not be forgotten, however, that this phenomenon is already observed in the southern Alps, where several perennial tree species have escaped from the gardens. This is also true in Portugal, where a species like Persea indica is considered an invasive species in the Serra de Sintra. At the opposite extreme, the lack of rainfall could instead lead to the development of savannas and deserts in vast territories in the centre and south-east of the Peninsula.

The great biomes in the western Mediterranean in the middle of the Pliocene. The great differences that are observed today already existed, being even more marked the difference between the Atlantic façade and the north of ka Peninsula, where they dominated the perennial forests (laurel forests) and the center and SE, where the vegetation was similar or even more open than the current (desert in the SE). / Fauquette S. et al. (1999) / Climate and biomes in the West Mediterranean area during the Pliocene / Palaeogeography, Palaeoclimatology, Palaeoecology, vol. 152, pp. 15–36..

The fact that we are returning to Pliocene climate does not necessarily mean that the ecosystems of the future will be absolutely similar to those of the past. The study of the past allows us to predict what the broad features of future ecosystems might be, but it is evident that these ecosystems could be very different from what they were. Many species native to distant lands will take advantage of the opportunity to expand and develop, and many of these ecosystems will be absolutely novel. New species could even appear as a result of the process of differentiation and speciazion that affects exotic species already installed or thanks to the game of hybridization. There are already several cases of absolutely new species in Europe, which raise such delicate questions as this one: can an absolutely new species born here and adapted to the current ecological conditions of the place where it has appeared be considered exotic?

The small groves of Siberian elm and trees-of-heaven that surround our cities are a current example of a novel ecosystem developed in conditions that did not occur naturally on the Peninsula.

The extent of the changes that can be anticipated already forces us to rethink many aspects of our environmental policy. Does it make sense to "pursue" exotic species in a world subjected to such important and drastic changes? Does it make any sense to want to force endangered species to stay in places that tomorrow will be unfavorable to them and where they are doomed to disappear? Until we've become aware of it, I fear that any effort, however admirable it may be, may not bear the fruit that is expected in the long term.

Friday, 5 July 2019

Paleo-autochtonous species (6): Pterocarya

One of the tree families that suffered the most from the effects of Quaternary glaciations on the European continent is, without a doubt, that of the Juglandacea. Although one species - the walnut - managed to survive in the southern peninsulas and another - the one we are dealing with in this article - is only present in the Caucasus, on the periphery of the continent. This family had a rich diversity of species before the ice ages with genera such as Juglans, Carya, Pterocarya, Engelhardia, Platycarya, Cyclocarya, etc. Many of these genera only survived later in the Asian SE and in North America, disappearing completely from the European continent. The most thermophilic species disappeared (at the end of the Pliocene), with only the two currently present genera (Juglans, Pterocarya) and the Carya genus remaining in our continent, which survived in the Iberian Peninsula until the middle Pleistocene and until much more recent dates still in Anatolia.

The Caucasian pterocaria (Pterocarya fraxinifolia) is a species present in the W of the Black Sea, the Caucasus and the N of Iran, with some dispersed and isolated populations in Anatolia and other southernmost points of Iran. It is a thermophilic species with high demands on humidity, riparian forests being its natural habitat. As you can see on the map below, the Caucasian pterocaria was a widespread species throughout the European continent at the beginning of the Quaternary (Lower Pleistocene). It was also very abundant, being in many places the dominant species in the pollen spectrum.

Although this species was considered extinct in the Iberian Peninsula since the Middle Pleistocene, the lake record of the El Cañizar lagoon, analyzed by Eduardo García-Prieto Fronce (1), has shown that this species survived in the E of the Iberian Peninsula until the last interglacial period (Eemiense), possibly until 67,000 years ago. The warming suffered by a good part of the European continent for several decades favors, today, clearly this species that has already become naturalized in some regions in which, cruel paradox of fate, is considered invasive.


Pterocarya	Family: Juglandaceae	Order: Fagales
Trees deciduous, monoecious. Branchlets with chambered pith. Terminal buds oblong, naked, or with 2-4 overlapping scales. Leaves odd- or even-pinnate; leaflets 5-21(-25), margin serrate. Inflorescences lateral or terminal on old or new growth, pendulous; male and female inflorescences separate: male spike solitary, lateral on old growth or at base of new growth; female spike terminal on new growth. Male flowers with an entire bract; bracteoles 2; sepals 4; stamens 5-18, anthers glabrous or pubescent. Female flowers with a small, entire bract, adnate to ovary but nearly free at base; bracteoles 2, adnate to ovary but nearly free above bract on posterior side; sepals 4, adnate to ovary, free at apex; style short; stigmas carinal, 2-lobed, plumose. Fruiting spike elongate, pendulous. Fruit a 2-winged nutlet, 4-chambered at base. Germination epigeal. Description: Flora of China

It is a relatively uncultivated species. Most of the pterocarias grown in our country belong to the eastern species (P. stenoptera) or to the hybrid of both (P. x rhederiana). According to the catalog published by the Madrid City Council, 347 specimens of this species were planted in the Madrid Río project, but I am not sure that they really correspond to this species (it will have to be verified in situ). Its cultivation does not seem to involve many difficulties. The region from which it originates has a sub-Mediterranean type climate very similar to ours and if the water requirements of this species are met, it should thrive without much difficulty. Its propagation by seeds does not seem too problematic. Without any previous treatment (except to preserve the seeds on the terrace), I managed to germinate three seeds and I have high hopes of achieving the development of the obtained specimens..

(1) Eduardo García-Prieto Fronce (2015) / Dinámica Paleoambiental durante los últimos 135.000 años en el Alto Jiloca: el registro lacustre de El Cañizar / Tésis Doctoral, Universidad de Zaragoza

Author: Adrián Rodríguez
Translation: João Ferro

Saturday, 29 June 2019

Lessons from Bialowieza

Most of you have never heard about me, about Bialowieza or even about what a primeval forest is, let alone had the chance to be in one. My name is João Ferro, I was born in Lisbon, Portugal in 1971, and I am a nature guide and animal tracker in the Bialowieza biosphere reserve in Poland and Belarus. You must be asking what a guy from Lisbon is doing in a place in the dead end of Europe far from his original home; well the answer is I am living my passion. My life is my passion and my passions are my life, and my main passion is to learn about life.

As far as I can remember, I always felt an enormous urge to be in nature and to learn about the secrets of life, no matter whether human life or wildlife. When I was a young child and teenager, I was very influenced by some great people and their capacity for communication and vision helped me to deepen my concepts about life and how to open horizons. Among the most important influences are Félix Rodríguez de la Fuente, David Attenborough, Jacques Cousteau, Gonçalo Ribeiro Telles and Bill Mollison. Ultimately, it was because of these influences that I am now living and working in the Bialowieza Biosphere Reserve. For the ones who don't know what Bialowieza is, here is a short summary:

•	Bialowieza is a forest complex with several levels of protection where we can find some of the best preserved temperate lowland forests in Europe, some of these parts are defined as being primeval.

•	Parts of Bialowieza forest are biosphere reserves since 1977 and a world heritage site since 1979.

•	The forest of Bialowieza has the tallest native trees in Europe and has no equal regarding the number and age of monumental trees.

•	Bialowieza harbours some of the last functional landscapes and ecosystems in Europe with outstanding biodiversity. It’s a unique place to understand and study uninterrupted cycles of nature (the water cycle, life cycle and decomposition cycle).

•	Bialowieza was also the place where the European bison was saved from extinction and where one of the biggest wild European bison populations can be found.

European bisons in the Bialowieza biosphere reserve. / Picture: Frank Vassen / Licence: Creative Commons.

Understanding the concept of a functional landscape and ecosystem as described above is a challenge for the majority of people I guide through the forest. I presume that a functional ecosystem/landscape is from a purely mechanistic point of view, a system where the natural cycles, evolution of species or ecosystems, and the interaction between individuals and species with the surrounding conditions is kept in balance. No matter what cultural, ideological, religious, political, philosophical, personal or educational perspectives may exist, nature’s mechanics are unchangeable and universal, no matter the continent, the climate, geography or time.

In our present culture, mass media, politicians, NGO's, activists, ideologies and individuals report that nature is in danger. This cannot be further from the truth - it's not nature that is in danger, it's our culture and way of living that is threatened and ultimately the existence of our own species since we are constantly disrupting the natural tendency of nature to be in full balance. Of course, many species face risk of extinction and probably many will be extinct in the near future, but this does not mean that nature is at risk. LIFE is very, very resilient and the planet has eons of time to develop new species that would play their own role in the cycles of nature with or without us.

The study of uninterrupted cycles of nature is only possible in very few european forests. Bialowieza is probably one of the very few places in Europe where all cycles of nature are in dynamic balance. / Picture: Jacek Karczmarz / Licence: Creative Commons

For us to understand nature basic’s functioning, we must know its main principles:

•	Nature is plastic: it evolves, changes, reshapes, appears and disappears according to its present conditions.

•	Nature is in constant evolution: it is a function of all the interactions and influences experienced by all organisms that may evolve or disappear.

•	Nature is not linear: nature is in opposition to what is taught in schools or by mainstream information channels. It does not evolve or move from point A to B in all circumstances; it looks more like a complex internet of infinitesimal relations of actions and reactions between all participants.

•	All species are important and at the same time limited: humans, for example, are part of nature. Like it or not, we are just one more species of no greater or lesser importance than any other species on this planet. We are shaped and limited by the same overall rules, both influencing and being influenced by the other species and limited by the present conditions.

•	Nature always evolves in the direction of homeostasis: meaning that given time, all cycles of nature will be in dynamic balance.

•	Nature always evolves in a constant direction to full potential climax: the full potential climax is achieved given time for evolution, availability, diversification and integration according to the local conditions and possibilities.

•	Nature does not have morals or ideology: in nature all organisms exist as far as they will be integrated and as far as they will be functional individually and collectively. A species that is not functional and is not integrated sooner or later will change or will become extinct. All species will try to LIVE and succeed independently of our moral, cultural or ideological judgement.

•	Nature has limits: in the nature of life there is one major limit - consumption can never be greater than the capacity of production, be it of a single organism, a full species or an ecosystem.

•	In nature production and consumption must be in balance and this is achieved by the regulatory principles of predation, parasitism, competition, symbiosis, mutualism and commensalism.

All of these principles are shaped by the primary influences of nature:

Time, Climate, Astronomical, Geology, Atmosphere, Water, Energy, Life, Death, Nutrients, Toxins, Balance

Bearing these principles in mind, one can ask what are we doing to nature and why are we in such a controversial moment in human evolution? Although this risks oversimplification, I can say that our present fundamental error as a civilization, despite our ideologies and scientific opinions, is a failure to understand the basic principles of nature in an impartial way. Through this blind-spot we are unable to align ourselves with the fundamentals of nature’s mechanics, or to understand sustainability in the true sense of the term.

Allowing logging in parts of the Bialowieza forests that were theoretically included in the Natura 2000 network of protected spaces, man now interferes directly in the major cycles of nature, that remained unaltered for centuries.

Sustainability in nature, in opposition to the present mainstream economic ideology, is in keeping with some basic factors that all of us should have learned in primary school:

•	Consumption can never exceed the production capacity of a system, for obvious reasons.

•	The number of consumers cannot exceed the production capacity.

•	The nutrient cycle output must always be returned; otherwise we walk towards impoverishment of the ecosystems and eventual collapse.

•	The input of toxins cannot exceed the capacity of their own neutralization.

•	The constituents of the planetary system cannot be changed in great measure, be it in the atmosphere or hydrosphere for example.

•	The water cycle is of major importance and special care must be provided to not disrupt this cycle, what we consume must be returned in the same quantity to the same place.

•	Our food consumption, be it animal, fish or vegetable, cannot disrupt the main cycles and must be integrated within the production capacity of the place.

So how did Bialowieza influence me into the point where I am now? Bialowieza influenced me since it is one of the few functional ecosystems in Europe and in the world. It gave me a perspective that no book can give, by watching, feeling, and learning about life in a place with minimal human influence in the past and present. The greatest of the lessons arrived and will always be there when I spend time in the forest, since nature is an infinite depository of information on life and an example for us humans individually and collectively. Everything mentioned in this blog, comes from this direct observation of nature's functionality.

A representation of the interactions between functional components in an ecosystem in dynamic balance.

But what is the concept of functionality? It's the same as homeostasis, the term is used in biology regarding the function of an organism, but I also use it to explain the balance of a macro-organism like planet earth. This is analogous to the Gaia hypothesis, and of course one can scale it down or up to a living system of any size. In order for a climax system to maintain functionality, the energy flows within it must have a perfect syntropic balance. This is a crucial point, because it is exactly the one we humans do not respect and ultimately leads to us walking towards Armageddon. Without understanding this term and respecting this principle, we are doomed to dysfunctional systems and ultimately to collapse since we still live in a culturally entropic value system and not in a syntropic one. While the universe may tend towards entropy, nature is pushing towards syntropy, and what is not able to live according to this principle is reorganized or dies and its constituent matter and energy are available for renovation or reorganization.

In a fully functional system minor disturbances will always tend towards a fast reorganization of the system and to a new homeostasis, while major disturbances, human or not, will cause a major disruption in the system that will need more time to adjust, to reorganize and become a major opportunity for evolution and reorganization of the system. One must always bear in mind that nothing is passive in nature, there is always some sort of change, the process of evolution is permanently directed towards a constant complexification of the system. This can be simplified for a moment in time over and over again but all systems tend towards this complexity. I exemplify this while guiding with an image everybody understands – imagine a grass lawn in a park, if there is no no maintenance of this lawn, over time the ecological law of succession will act and the same grass lawn after a few years will become a bushland dominated by bushes and a few trees, give it some more time and it will become a young forest dominated by pioneer tree species, after about 150 years and it will become a mature forest and so on. The issue with this concept is that most humans tend not to know this obvious principle or to be actively opposed to it, thinking that the ideal landscape is stable, according to a certain personal concept, be it a boring lawn, a potato field or grandma's flower garden and they all make a gigantic effort to contradict what is one of the major rules of nature, constant change.

Most of our interventions in the landscapes are in reality an enormous effort we undertake to work against one of the most important rules of Nature: Nature always evolves in a constant direction to full potential climax.

When this concept is fully understood, the idea of invasive species or noxious weeds sounds absurd. I can agree that initially there will be a certain level of disturbance when a novel species establishes itself, but with time everything will tend to balance and this will be particularly fast if the ecosystem has rich possibilities or is already in balance. So why is this concept of invasiveness so advertised? This is a complex net of ideas and interests but to simplify is based on an erroneous concept of life on this planet and cemented with fear and exclusion. Another concept I've learned by living here in Bialowieza is that there is no exclusion in nature, any organism with time will become extinct or become integrated in the system. Specific species might profit and dominate for a certain amount of time (maybe for a short human lifetime), but sooner or later the natural system will balance the species composition. Here I can give another example – imagine an exotic pine plantation in France, for example. With no human maintenance, different species available in the area will start to install themselves in the pine plantation and after 200 or 300 years, it will not be an exclusive pine plantation anymore, maybe some pines will still be there but it will tend to become a complex mosaic of different species in a mixed forest.

In an abandoned Eucalyptus plantation in the Kalakad-Mundanthurai reserve, in the south of India, the number of tree species increased since 2005 and now is similar to the number of tree species in the neighboring primigenial forest. However, these plantations have been mainly colonized by pioneer species for the time being and a long time will be necessary to see the original species make their come back. / Fotografía: Abandoned plantations in forested areas may not recover fully: Study

Most people also do not realise that nature's cycles are extremely long - much greater than a human lifespan. The full development of an ecosystem from the moment of disruption might take about 1000 years to become a full-fledged system, from its present over simplified state (like a lawn) until it becomes a primeval forest with no major signs of human influence.

To finish with a major idea – LIFE goes on and on and is in constant change, no matter our personal views and assumptions. There is nothing else greater than LIFE in its capacity for permanent evolution and complexification.

Author: João Ferro

Wednesday, 5 June 2019

Paleo-autochtonous species (5): Cedrus

Cedar of "La Francesa", in the region of Béjar (Salamanca). It is undoubtedly one of the most imposing Atlas cedars in the Iberian Peninsula, in a region where this species was probably still present in the Holocene.

The quaternary glaciations were a real catastrophe for the continent's biodiversity, and its tree flora greatly impoverished during this period. The cedars, so common today in our parks and gardens, belong to a genus that was one of the last to disappear from the continental zone of the European continent. A single species, relictual, was able to survive on the island of Cyprus (Cedrus brevifolia), being this species the last representative of this type in Europe.

Origin and expansión

Confined now to the mountains of North Africa, southern Turkey, the Middle East and the Himalayas, the origin of this genus is found in East Asia, as shown by phylogenetic studies (1) and fossil evidence. From there, it expanded to the west, differentiating firstly the Himalayan cedar. After colonizing the whole south of the European continent, an eastern population was differentiated from which the cedar of Lebanon and the cedar of Cyprus would be born and a western population reaching North Africa through the Iberian Peninsula when the Strait of Gibraltar was closed in the Yonger Miocene (Messinian).

It is interesting to note that the differentiation of cedar, a result of the isolation of different populations, does not prevent the crossing of different species, which often makes it difficult to identify the individuals planted in our parks, which may be the result of the crossing of several of these species . This process of differentiation seems to be quite old in any case, prior to the glaciations. At the end of the Pliocene, the cedar (sensu lato) was present in all reliefs from the south of the continent, from the Iberian Peninsula to the Caucasus.

Regression and possible refuges

Cedar was already at the end of the tertiary, an average elevation tree that coexisted in many places now missing with conifers as Tsuga and Cathaya. These species took refuge during the glaciations, in the peninsulas of the south of the European continent. Its presence is commonly accepted in the Italic Peninsula and in the north of the Iberian Peninsula until the Middle Pleistocene. The presence of cedar pollen in more recent sediments is generally attributed, however, to wind transport from North Africa. The detailed study of some recent pollen diagrams suggests, however, that cedar could be present in the Peninsula until much later dates.

Pollen diagram of deposit of Cuerpo de Hombre (Sierra de Gredos). Notice in particular the simultaneous decline of the pine and the cedar at the moment when man arises.

A recent study in postglacial sediments of the Sierra de Gredos [2] reveals the more or less continuous presence of cedar in one of the analyzed profiles, which is hardly explained by a contribution from the North African wind. The pollen diagram of this profile (Cuerpo de Hombre) shows that the emergence of cedar always coincides with periods when the tree cover reaches a maximum, as reflected by the pine curve. The disappearance of the cedar, on the other hand, coincides with the disappearance of the pine at the time when the forests of this region were overthrown and that these lands completely changed of use. A more random presence of cedar would have been more compatible with wind transportation. The most convincing argument in favor of a local origin of this pollen, however, is its total absence in the other profiles studied in this same region. It seems very improbable that after a journey of several hundred kilometers, the cedar pollen appears "concentrated" in a single profile. Anyone who has experienced an episode of "desert dust" knows perfectly well that when this happens, the desert sand covers vast expanses indiscriminately.

A ski resort in the Pyrenees on a desert dust day last April (2018) / Photography: https://twitter.com/hashtag/lluviadebarro

A very similar situation is observed in other regions. In Andalusia, for example, cedar pollen appears in significant quantities in sediments at the Bajondillo grotto (Torremolinos), where it has a continuous presence in the pollen diagram until the end of the last glacial period, coinciding with the emergence of the Aleppo pine [3]. Here again, it seems that it is not the result of mere coincidence. But in the same way is the total absence of the cedar in the sediments of the same time in the cave of Gorham (Gibraltar), only to 60 km more to the west, what is more remarkable in the context of a contribution by the wind. It should be noted that the cedar itself is present in this same deposit in older sediments (Upper Pleistocene).

Pollen diagram of the cave del Bajondillo (Torremolinos). Note the simultaneous development of Abies, Betula and Cedrus at the end of the last ice age.

This heterogeneity of cedar presence in Upper Pleistocene and Holocene sediments is explained much more easily by the presence of small Cedar populations in the Iberian Peninsula. Its disappearance, as shown by the Sierra de Gredos example, would have been very recent and the man apparently has a clear responsibility because the species has not survived to this day. This will only be definitively demonstrated on the day that Holocene macrorrests are found attributable to this species. For now it is only a suspect, but the evidence clearly indicates that it would be present. For now, as far as I know, no one has explained the absence of the cedar in all places near and contemporaneous with those in which its presence was revealed.


*Cedrus*	Familia: Pinaceae	Orden: Pinales
Trees evergreen, monoecious; branchlets strongly dimorphic: long branchlets growing several cm each year and bearing very slow-growing, lateral short branchlets; winter buds small, scales persistent. Leaves spirally arranged and radially spreading on long branchlets, shorter and very densely clustered on short branchlets, needlelike, triangular or ± quadrangular in cross section, stiff, stomatal lines present both adaxially and abaxially, most numerous abaxially, vascular bundles 2, almost fused, resin canals 2, small, marginal. Cones borne on apex of short branchlets, solitary, erect. Pollen cones with many spirally arranged microsporophylls; microsporangia 2; pollen not saccate. Seed cones erect, light purple at fertilization, maturing in 2nd(or 3rd) year; ovulate scales spirally arranged, sessile, with small bracts and 2 ovules adaxially. Seed scales closely arranged, large, woody, those at base and apex of cone sterile, deciduous at maturity. Bracts minute, falling together with seed scales at maturity from persistent, central axis. Seeds with large, membranous wing. Cotyledons usually 6-10. Germination epigeal. 2n = 24. Descripción: eFlorss

A bright future

Climate change represents, for the Atlas cedar, a serious threat and an extraordinary opportunity. Rising temperatures, in fact, have already pushed the lower-lying populations of North Africa to the limit. Illegal logging and overgrazing are also very serious threats in their area of origin and the future of the species in North Africa is very uncertain. Fortunately, French foresters soon realized the potential that this species could have in the Mediterranean region and the species was planted in France practically since it was discovered (by Europeans). The cedar forests of the Luberon and Mont Ventoux today show the extent to which this species is perfectly adapted to the sub-Mediterranean climate which is precisely one of the types of climate that most will see its area extend north to the end of the century, making this species one of the most promising for the future.

Cedar grove in the Petit Lubéron massif (France), where they cover about 207 ha. only in the territory of the small town of Lacoste. The planting of cedars in this massif that was totally "peeled" in the nineteenth century was a resounding success, becoming its cedar forest one of the great attractions of the region. Photography: Tourist Office of Lacoste.e

Paradoxically, this species did not arouse in Spain the same interest as in France and was only planted on a very small scale. (Atlas cedar in the Iberian Peninsula). The current climate must, however, lead our authorities to become more interested in this tree, which was one of the most important species of our mountains before being a victim of glaciations and overexploitation. The quality of its wood, its relative resistance to drought and its low flammability are, in any case, compelling reasons that argue in its favor.

		(1) Qiao C-Y. Et al. (2007) / Phylogeny and Biogeography of Cedrus (Pinaceae) Inferred from Sequences of Seven Paternal Chloroplast and Maternal Mitochondrial DNA Regions / Annals of Botany, Vol. 100. pp. 573–580,

		(2) Ruiz-Zapata1 M.B. et al. (2011) / Dinámica de la vegetación durante el Holoceno en la Sierra de Gredos (Sistema Central Español) / Bol. R. Soc. Esp. Hist. Nat. Sec. Geol., Vol. 105 (1-4), pp. 109-123

		(3) López-Sáez JA, López-García P, Cortés Sánchez M. 2007. Paleovegetación del Cuaternario reciente: Estudio arqueopalinológico. En: Cortés Sánchez M. (Ed), Cueva Bajondillo (Torremolinos). Secuencia cronocultural y paleoambiental del Cuaternario reciente en la Bahía de Málaga. Centro de Ediciones de la Dipu- tación de Málaga, Junta de Andalucía, Universidad de Málaga, Fundación Cueva de Nerja y Fundación Obra Social de Unicaja, Málaga, pp 139-156

Author: Adrián Rodríguez
Translation: João Ferro

Saturday, 1 June 2019

Paleo-autochtonous species (4): Avicennia

One black mangrove (Avicennia germinans) recently established grows in the middle of a brackish swamp north of St. Augustine, Florida, near the northern border of this cold-sensitive tropical tree. Mangroves are expanding in northern Florida as the episodes of intense cold become rarer. Photograph: Kyle C. Cavanaugh (Landsat Satellite Sees Florida Mangroves Migrate North)

I evoked in a previous article (Ecosistemas terciarios desaparecidos), the presence of mangroves on the southern coast of the Iberian peninsula at the end of the Tertiary and early Quaternary, documented by the discovery of extraordinarily well preserved fossils whose study is still underway (Hallados fósiles de manglares de hace 2,5 millones de años en Cuevas). Based on this I imagined, in another more recent article (Rumbo al Plioceno), as in the future more or less distant the Romería del Rocío possibly have to progress in boats between the roots of the mangroves. In writing this article, however, I was not aware that the possibility of seeing a mangrove grow on our coast may not be as far as I expected...

Current distribution of Avicennia germinans

As you can see in the previous map, the black mangrove (Avicennia germinans) reaches in North America the eastern shores of Florida. The northern boundary of its distribution does not seem to be so marked by average annual temperatures or rainfall, but by the fact that there are cold days when the temperature falls below -4 ° C. Below this temperature, black mangrove seedlings do not survive. On the other hand, a relatively recent study [1] has shown that global warming has led to the development of the mangrove swamp in the north since the 1980s, where the tree colonizes coastal areas.

As you are intelligent and have agile minds, you have surely noticed seeing the map of distribution of this species that the north of Florida is situated at about the same latitude as the Canaries. And as you well know, the Gulf Stream flows southward off the coast of North America, bringing cold waters from the north, and rising northward off the coasts of Africa and Europe. In addition, there are many areas of southern Spain, where temperatures do not drop below 0 degrees. Huelva, for example, is often the city of Spain with the highest minimum temperature. The cold ever in this city was -5.8 degrees and was achieved in 1938. Later, it only reached that limit of -4ºC in 1954. The big question, you guessed it, is this: could the black mangrove survive in southern Spain? As far as I know, no one happened to try to plant this species in our country, but seeing that the climatic limitation marks the limit of its distribution in Florida, I wonder if perhaps the experiment is worthwhile, although only to clear the doubts. In the worst case we would have a small mangrove swamp on our coast...

Potencial distribution of Avicennia germinans suposing that this species is able to survive in zones where frost is exceptional. Author: Joâo Ferro.


*Avicennia*	Family: Acanthaceae	Order: Lamiales
Shrubs or trees, maritime. Branches terete, sometimes 4-ridged when young. Leaves opposite. Inflorescences small spikes or capitula; bracts and bractlets ovate, shorter than calyx, persistent. Flowers small, opposite, sessile. Calyx cup-shaped, deeply 5-lobed; lobes overlapping, persistent. Corolla nearly actinomorphic, campanulate, shortly inserted on an inconspicuous disc; lobes 4 or 5, upper lobe often broader than others. Stamens 4, adnate to apical part of corolla tube. Ovary imperfectly 4-locular, with a free central winged placenta; ovules pendulous. Capsules subtended by persistent calyx, dehiscent into 2 leathery valves. Description: Flora of China

The presence of this genus on the European continent and in the Mediterranean is documented until the beginning of the Quaternary. Apparently the mangroves survived longer in the eastern Mediterranean basin, disappearing less than 2 million years ago around the Black Sea.

Latest records of Avicennia mangroves in the Mediterranean [2]

I did not live in Madrid, far from the sea and not have a holiday in very favorable areas, I do not think I would hesitate to try. The region of Huelva seems a priori to be the most favorable, but I have to admit that I do not know this region very well. Can you imagine how extraordinary it would be to have a small mangrove swamp on our coast? Not only for the curiosity but also for the multiple benefits that this type of ecosystem brings where it develops. Everyone probably knows that the mangroves are authentic nurseries for many species of fish. There is no doubt in my mind that such an initiative would quickly come to an end, with initial reluctance, the unconditional support of many people. Yes, the idea is launched. I hope that in this country people are even more insane than those who write these lines...

		[1] Cavanaugh K. C. et al. (2014) / Poleward expansion of mangroves is a threshold response to decreased frequency of extreme cold events / PNAS, Vol. 111(2), pp. 723–727

		[2] Biltekin, Demet. (2010) / Vegetation and Climate of North Anatolian and North Aegean Region Since 7 Ma According to Pollen AnalysisTésis / Tésis / Université Claude Bernard – Lyon 1 & Université Technique d'Istanbul

Author: Adrián Rodríguez
Translation: João Ferro