grow and multiply…ECOLOGICAL footprint
Since the distant times of the hunter-gatherers, when a few million individuals roamed the Earth, to the more than 7 billion people of today, the population has not stopped growing.
And the Earth?
While the Earth's population grows exponentially, its surface remains constant...51 billion hectares, of which we only use about 11.4 billion, or a little less than 25%; the rest are deserts, polar ice caps and deep oceans.
These 25% ensures the survival of the Earth's more than 7 billion inhabitants, which means that today there are less than 1.6 hectares per inhabitant.
As the usable surface area has remained roughly constant over time and the population has grown, the available area per inhabitant has been decreasing; in 1900 there were 5.6 hectares per inhabitant, in 1950 only 3 and ... in the future????
In the early nineties of the last century it became evident that the speed at which natural resources were being used up was exceeding the planet's regenerative capacity. Two concepts emerged:
- biocapacity which estimates the capacity of ecosystems to renew themselves;
- the ecological footprint which estimates the area of the planet necessary to produce the resources used (agriculture, fisheries, livestock and habitation) and assimilate the waste generated (especially carbon dioxide).
Changes in technology and land use over the last 50 years have increased the Earth's biocapacity by 27% but... in the same period of time, the ecological footprint has increased by 190%...
This means that since the 1970s terrestrial ecosystems have no longer been able to ensure human consumption in a sustainable way.
It is then possible to define the OVERSHOOT DAY, which is the calendar date when all the resources that the Earth is capable of regenerating in that year have been consumed.
An impossible balance….?
Stone Age & Iron Age …. ALWAYS !!!
Let's not forget that we left the Stone Age and Iron Age a few thousand years ago and without all those materials all of our constructions would literally fall apart!
from houses to cars ... and airplanes ... and boats ... and ...
Each inhabitant of the Earth consumes on average more than 400kg of iron per year... that's the equivalent of about 500 Eiffel Towers... and this consumption is increasing...
a key material in construction
On a planet where the population is increasing at a rate of more than 225 000 new inhabitants per day, the need for more construction is inevitable.
Weathering, erosion and rock transport cannot produce and accumulate sand at the rate at which it is used. All the more so because desert sand, being made up of very rounded grains, is not suitable for construction. That is why the Burj Khalifa in Dubai was built with sand from... Australia....
Geological footprint????? An inevitably different approach
Our societies depend on geological resources. They always have been!
Although minerals and rocks are constantly renewed according to the rock cycle, it is not possible to talk about geocapacity, because the rhythms of this renewal are geological but consumption is done at human rate.
Therefore, the consumption of geological materials always represents the use of a finite resource. It is urgent to rethink the way we use these resources, because although they are often abundant, they are not never-ending. Whatever the future, we will always need to consume geological resources.
Therefore it is fundamental that these recourses be studied in order to guarantee their more rational use, as well as the minimization of the negative impacts associated to their extraction.
the water we drink ...
It is not possible to understand Ancient Egyptian civilisation without understanding its relationship with the Nile River. Being located in a desert region, the Egyptians depended on the water transported by this river not only to survive but also to flourish. If this is one of the best known examples of the relationship between the development of a society and water, it is by no means an isolated case.
Indeed, it is water that makes possible not only the development of societies, but even the very existence of Man. Understanding where the water we drink comes from is therefore fundamental if we do not want to endanger our own existence and well-being.
where is the water in depth?
Although there are other sources of drinking water (e.g. rivers, lakes, reservoirs and glaciers), groundwater has been an important, if not fundamental, resource for meeting human needs throughout the ages. Springs, wells and, more recently, boreholes are the means used to access this essential source of fresh water.
But how deep does the water appear?
Groundwater is therefore an essential part of the hydrological cycle, corresponding to its circulation more or less deep. But for groundwater to be captured under economic conditions, i.e. to constitute an aquifer, it has to be concentrated in reservoir rocks.
The concentration of water at depth generally depends on three factors:
the existence of impermeable lithologies
e.g. clays and marls that act as barriers preventing water dispersion.
the existence of a favourable geological structure
e.g. folds that act as a water trap.
the existence of a reservoir rock
e.g. sandstone where water is concentrated.
Part of the water infiltrates giving rise to aquifers
Are there any deep caves capable of storing the great quantities of subterranean water existing on our planet?
The existence of deep caves is a situation which only occurs exceptionally and even then only in rocks which are easily soluble, such as limestone and marble. Therefore, the water in aquifers does not occur in the form of large continuous volumes, but rather disseminated in the voids existing in the rocks.
Basically groundwater comes in two forms:
Disseminated in the pores of permeable rocks (e.g. sandstone);
by exploiting the network of fractures in impermeable rocks (e.g. shale, limestone and marble).
However, whatever the situation, for groundwater to circulate the voids, pores or fractures in the rock that make up the aquifer have to communicate with each other.
As groundwater is the result of partial infiltration of rainwater, aquifers are very vulnerable to pollution caused by man.
This aspect is all the more serious when a large percentage of the world's pollution depends on this water for its survival (about 98% of fresh water is underground...) and this population has been growing at a rate that endangers the delicate balance of our planet.
Preventing the pollution of aquifers implies a good knowledge of the underground water circulation system in order to prevent the pollution of the areas where the water circulates.
Yes, drink water!!! But…
water is life, but polluted can be death
extinctions.... the rule but…
are we causing a biological catastrophe???
Of the 4 billion species that are estimated to have existed on Earth in the last 3 500 million years, 99% are extinct. This shows how common extinctions are, although they are usually offset by the formation of new species.
However, with increasing frequency, biology studies have shown that human activities have been causing widespread extinctions of species and populations and a mass extinction may be underway.
If this happens, biological recovery will take place over a period of time that has nothing to do with the human time scale. Indeed, the evolution of new species takes at least hundreds of thousands of years, and recovery after a mass extinction probably takes a few million years...
When comparing the diversity of current marine invertebrates with the one that existed 550 million years ago, it can be seen that EVOLUTION gave rise to an amazing process of diversification that is not uniform:
- on two occasions a maximum diversification occurred (Ordovician and Meso-Cenozoic radiations)
- on five occasions, more than 3/4 of the species of living beings on our planet suddenly disappeared (the extinctions of the late Devonian, Permian, Triassic and Cretaceous)
The causes of these great extinctions are varied (generalized glaciations, gigantic volcanic eruptions, formation of mountain chains, impacts of enormous meteorites and...), but they show us that the evolution of Life on Earth was not a process conditioned only by a biological processes
Without these global catastrophes that have been affecting our planet throughout geological times, the evolution of Life would have been very different and... we wouldn' be here...
The individualization of geological time unit is only possible because their fossiliferous content is not only different, but there are sudden transitions between associations of fossils of successive units.
These catastrophic events have been repeated at different scales throughout the history of our planet. The main transformations of the fossiliferous register allow separating the Geological time in Eons, Era, which, in turn, are divided into Periods/Systems.
Minor catastrophes give rise initially to Epochs and later to Stages. Even within stages it is still possible to distinguish minor subdivisions based on detailed biostatigraphic studies ...
A linear evolution ????
The history of horses...
Often the EVOLUTION of horses is represented in a LINEAR diagram from the ancestor Hyracotherium to the modern horses of the gender Equus. The five genus usually depicted show a progressive increase in body size and teeth associated with a reduction in the number of toes, which gradually become hooves. This enormous SIMPLIFICATION of the complex evolutionary tree of horses ( see information on the table ) should be avoided because, besides containing mistakes ( for instance, the genus Pilohippus was never an ancestor of the present horses ) it induces the idea of an evolutionary course too simplistic and directed to modern forms which is very far from reality.
from forests to the prairies
Hyracotherium appeared about 55 million years ago, the ancestor of the whole family of the Equidae, to which today's horses belong (species Equus ferus). The size of a cat, Hyracotherium had toes on its legs which are able to dig into the soil of the Forests where it lived. Its teeth were small and not very robust, adapted to chew the tender leaves and stems on which it fed. A chance in the evolutionary process, eventually led some of their descendants from the forests to the extensive prairies, where their toes were not very efficient for running; gradually the equine legs evolved into the hooves of modern horses. At the same time their teeth became more robust, because the grasses of the prairies were stiffer than the tender leaves of the forest...
the continuity of evolution.
Mount Isosomour in the Alnif region of southern Morocco is formed by a succession of slightly deformed rock layers. These layers have been deposited continuously for more than 15 MILLION YEARS, allowing us to better understand the transition between lower and middle Devonian. A family of TRILOBITES (a class of marine arthropods extinct for more than 251 million years) is very well represented in this region; it is the family Phacopidae. INSIGNIFICANT CHANGES between generations have allowed the EVOLUTION of several genera , from Reedops maurulus of the lower Devonian to Drotops armatus of the middle Devonian.
Biomorphus makes it possible to visualize the importance of "insignificant" changes when repeated a large number of times...
FROM THE EXPANSION ON EARTH TO THE EXPANSION ON SEA: IX CENTURIES OF DEVELOPMEN
Until the middle of the 20th century, the expansion of countries was essentially at the expense of the annexation of submerged lands. With the technological evolution, by opening up the possibility of exploiting marine resources (both living and non-living), alerted us to the economic importance of oceanic zones. This new interest has led to a series of international agreements aimed at defining the sovereign rights of coastal states in order to protect the immersed part of the territory and the exploitation of the natural resources therein. Portugal's evolution must be seen in this context.
The exclusive economic zone with a maximum width of 200 nautical miles, in which Portugal has sovereign rights to exploit the natural resources existing in the water column, soil and subsoil of the sea.
In 2009, EMEPC concluded the Continental Shelf Extension project, which has since been presented to the United Nations. The limit of the new map of Portugal, which, if definitive, will enclose an area similar to that of the entire European Union, establishes Portugal's sovereignty over the soil and subsoil of the new underwater areas.
The foundation of nationality took place on 5 October 11433, when Afonso VII of Castile and Leon recognised the independence of the Condado Portucalense. The rapid succession of conquests that followed meant that by 1300 the current border of mainland Portugal was roughly defined.
In 1956, Portuguese law established the underwater platforms defined by the bathymetric of 200 meters, whenever they were beyond the territorial sea (6 nautical miles). In 1977, the territorial sea was extended to 12 nautical miles and, in 1978, it was defined.
Millions and Millions of Years The imposssibility of understanding???
The theory of evolution shows us that any type of life resulted from the slow transformation of previous life forms. Bird's ancestors started to diverge from the dinossaur group about 170 million years ago! The first dinossaurs appeared about 230 million years ago from reptiles! The first reptiles appeared about 320 million years ago from amphibians! The first amphibians had their origin in fishes about 370 million years ago. and... ...all living beings were the result of the slow and complex evolution throughout more than 3500 million years from a common ancestor as predicted by Darwin: "Therefore I deduct by analogy that probably all living beings that have at any time lived on earth descended from a single primordial being". If UNDERSTANDING the process of the Evolution of Life is not simple, a greater challenge is trying to understand periods of TIME measured in millions of years. A simple analogy helps us to understand the immense dimension of this task... 1 KILOGRAM OF RICE is about 50000 grains, which means that 20 Kg are about a million grains. Therefore, one million years is the amount of time needed to eat 20 kilograms of rice if we eat 1 grain per year... And one million years is just the time unit... Birds appeared 3,4 Tons of rice ago... dinossaurs about 4,6 Tons ago... reptiles about 6,4 Tons ago... amphibians about 7,2 Tons ago... and... the first common ancestor more than 70 Tons of rice ago... Can you imagine???
HOW MANY GRAINS??? HOW MUCH TIME???
How many grains of rice are in each container?
How many years will have passed if you eat a grain per year? Can you point an event which has ocurred approximately in that time?
Vulcanic breccia covered by a dark crust of iron and manganese oxides.
The iron-manganese crust constitutes a mineral resource with high concentration of Cobalt and Nickel as well as other metals with industrial aplications. The concentration of these metals here is 10 to 100 times superior when compared to the rocks that constitute Earth's crust. Sample taken by dredging at 1700 m depth in the Seamount Great Meteor in the 31st of May 2007 during the oceanographic campaign EMEPC/Açores/G3/2007.