isolated again from the inoculated, diseased experimental host and identified as being identical to the original specific causative agent. However, this has changed someway currently. Today we know it is more complex and there is more possibilities.
Other infectious agents you may have heard are Anthrax, caused mainly by Staphylococcus aureus; the tuberculosis by Mycobacterium tuberculosis (Koch); and cholera by Vibrio cholerae; three bacteria with a long history of close relation with mankind and animals also but that only were the incipient onset of microbiology. As many parasitic or infectious diseases are strongly linked to bad conditions of health, as it was usual and even now is common in many places of the world: poor lighting conditions, non potable waters, lack of hygiene habits, high temperatures, and opportunities of colonizing for this little bunch of species. And these facts lonely are not science, but should be a goal for the science.
(All photographs are a Creative Commons source)
For many years, in addition it was suspected that the evolving of this group of bacteria, beginning from the colonizing of other beings and ending on the colonizing of animals and humans, being known its jumping over biological barriers. It was implemented the use of antibiotics in the fight against infectious diseases (W. McDermott, M. Finland, L. Weinstein et al.) from the 40s. Only since the 60s (J. Lederberg, T. Watanabe y E. S. Anderson, N. Datta, H. W. Smith) it was recognized the horizontal transmission between species of the resistance genes to antibiotics. It was the first time it was clearly known the opposite effect to desired: emerged that we had caused a change we had never desired.
Years after it, also were checked the infections by Campylobacter jejuni and Escherichia coli in humans with evident resistance to quilonones, whilst Salmonella sp. and Staphylococcus aureus coming respectively from birds, cows and pigs. The quilonones are an antibacterial drugs that avoid the breeding of bacteria, discovered in 1962. The use of these drugs in poultry has had among other consequences, the transmission of bacterial strains resistant to the drug to humans who consumed the birds (these strong strains were called Clostridium difficile) and the methicillin-resistant Staphylococcus aureus or MRSA, which provokes the hospital-acquired infection or HAI (nosocomial infection), this last is becoming a widely spread infection in hospitals. All these discoveries go to the same bag: as beings, as part of a complex ensemble of beings and relationships, bacteria have changed and change continuously, by natural causes and also by human causes, evolving like all being to survive against their own disappearance. The use of drugs cannot stop this phenomenon, so at the same time are creating new problems, some known, but are all? We cannot say that the research is useless, but we should start to decide what supporting with our payments, with our purchases, in every field of our lives. The tools sometimes can counter the goals, or the goals change and increase according to changes provoked by tools.
Then, why we would not think the soils would not have been affected by such as strong changes, chemical treatments, simplification of specie, introduction of modified genes and organisms, loss of nutrients and communities? And all this in the most important meeting point, the soils? Precisely where every being keeps in permanent contact with others (though invisibles for us), and relationships are basis for life or death, as we now know, for everybody.
Not, it never was forgotten, instead it was belittled, despite the high number of compounds applied over fields or expelled into the atmosphere, over 2,000, not only the dirty dozen. What to believe? Well, then ... the earth is round and rotates; the interchange between species is fully open, more than Internet. Tired of read? I am sorry. I would rather you go for a walk and let stand all this a bit: should see it from afar, listen and look better after putting distance: we have not yet reached the core.
But amidst all this events there were two World Wars which were the second opportunity to develop chemicals with “great purposes,” as were the chemical war agents or CWA (the first time it was used massively the chemical war was by the hand of the Spanish Army, in the Riff's war in 1925, where was applied the mustard gas), and the developers were the chemical companies. This history is so intrincated, so I have believed convenient to explain it into a map: The chain of chemical companies. Is a conceptual map constructed and gradually revised, as a part of a bigger conceptual map that will need at least two years to be fully developed. You can view it (fully operational) by using the free program IHMC CmapTools. This story gathers actions from chemical companies in one issue that affects not only environment but also economic and health issues, and already was shown across films and reports, unfortunately, sometimes as way to move people up and down. However, it is a link in a larger chain. As well as in other matters, the core of the matter is that nobody will be worried about if does not know anything relevant, and it occurs with the 99% of population in the world. It is very easy for people to not strain.
The attacks against the soils.
What are the main threats that suffered and continue suffering the soils? Some years ago, it was necessary to define where this occurred: nowadays, hardly is necessary because it is widespread.
Now are known very well the stronger threats: soils have suffered successive destructions. It began from the bad practices as depth tillage and subsoiling have led the increase of water and wind erosion, specially when some terrains were fully dismasted: the coverage removal and consequent loss and weakening of structure soils; an over tillage when soils needed a rest; the high decrease of organic matter in tropical soils that have lighter and faster turnover in its carbon cycle; the compaction by the overweight of hundreds of passes that tractors make over it; the loss of soils, which are carried mainly downhill by strong rainfalls, displacing tons of minerals and nutrients, destroying structures, in a progressive, cyclical and yearly action; the loss of organic carbon, key player, which decreases simultaneously with water and coverage; the loss of biodiversity, by the former events and by monocultures, by weedkillers and pesticides, by invasive species, or by weakness appeared with the changing climate conditions; the salinization or sodification, as result of various actions, as the excessive withdrawal of underground waters, a bad irrigation, and a more intense evaporation roused by bad practices; the pollution by pesticides and fertilizers, which have leaded to establish law levels of nitrates and sulfates allowable in soils, when the removal of those ones is already unaffordable, and are available for any creature, and you can find in every little stream running; and in some areas, the contamination with metals, in different degrees of intensity, and the pollution of hidden waters that keep in depth or running under the earth.
With this scenery, nobody could say that microorganisms do not react to this changes: and not only microorganisms, also arthropods (bees included), yes, mammals and ... Us!
Do we know why it occurs? Yes, of course we know. Do we know what we should do? We know it perfectly. Are we studying and working on it? Not only that, but also spending tons of money and time in investigate the already known, again and again, reporting papers and studies and research, and creating databases and maps, creating systems to do the already done (it was exhausting, but an intense searching of organizations, groups, joints, programs, etcetera, returned me the fantastic and staggering number of at least more than 7.000 different groups in the world, and hardly fifty are actually doing a good work): we know perfectly the solution, but the responsible for make the change principally are you, as customers, purchasers or as farmers. As customers, our habits for eating, work, make business and purchase, can draw all that could happen in the market and in the origin of the chain. As farmers or peasants, we can decide what means we want live with, and how we want preserve and improve our lands and forests, all are ours. Nobody could prevent us from doing that actually. We can only prohibit us the change, mentally, and culturally.
Could hold once again the soils its mass alive?
That is a very good question. And the answer is: if we do not press it so much ... then swiftly, to the extent to be allowed the dynamic rec
overing of their natural processes. Resilience is a property which either soils as the ecosystems have, and some trials of recovering have shown the ease when disappears pressure and, besides science, is applied the common sense. It has been the case in the Guanacaste National Park in Costa Rica. The "green restoring" began with a couple of Americans, the son of a US Fish and Wildlife Service Director, a PhD. in biology Daniel H. Janzen and his wife W. Halwachs (both ecologists). With an initial intense deforestation suffered by tropical forests, were recovered habitats of the Guanacaste region that existed before the American colonization: it was considered the returning to biotopes existing valuable, where coexist arid dry forests, covered forests, tropical rainforests, creeks, mangroves, rivers, tracts of scrub. He conducted the education, training and awareness of local community, passive restoration through fire control and livestock, and an active restoration by dispersing seeds and propagules of native species. But sensibly, the starting premise was to achieve an area that could inflect the preservation of biodiversity and local economic activity never