<\/o:p><\/SPAN><\/P> <\/o:p><\/SPAN><\/P> \u00bfY que decir de la aseveraci\u00f3n de estos autores sobre la importancia del pH?. Ya han detectado otro tipo de determinismo<\/SPAN><\/B>. Pero dudo que todo sea tan sencillo como los autores defienden. La biomasa y diversidad de los microorganismos en los \u00e1cidos en Espa\u00f1a var\u00edan enormemente<\/SPAN><\/B>. Ya hablamos de este hecho tambi\u00e9n, as\u00ed como que emigran en ambientes semi\u00e1ridos a los horizontes m\u00e1s profundos tan pronto como el clima les es desfavorable. <\/SPAN>Por tanto al muestrear exclusivamente los horizontes superficiales (\u2026) \u00a1m\u00e1s de lo mismo!. <\/o:p><\/SPAN><\/P> <\/o:p><\/SPAN><\/P> Resumiendo se trata de un trabajo que, por partir de premisas err\u00f3neas, nos lleva a conclusiones falaces<\/SPAN><\/B>. No digo que los resultados<\/SPAN><\/B> no alberguen valor alguno. Lo que ocurre es que no son extrapolables para el conjunto del suelo<\/SPAN><\/B>. Sin embargo, son muchos los expertos en biolog\u00eda del medio ed\u00e1fico que defienden, sin una base emp\u00edrica adecuada, que casi toda la actividad biol\u00f3gica y biomasa microbiana se concentra cerca de su superficie. Y es obvio que en tanto en cuando continuemos muestreando mediante este tipo de dise\u00f1os seguiremos corroborando una verdad a medias, que en muchos aspectos es peor que una mentira rotunda. S\u00f3lo se ve lo que se explora. As\u00ed no se progresa en ciencia<\/SPAN><\/B>. <\/SPAN>Por lo tanto me atrever\u00eda a se\u00f1alar que a\u00fan desconocemos los patrones de la biodiversidad, y distribuci\u00f3n espacial <\/SPAN><\/B> <\/SPAN>(en un perfil) de los microorganismos en los suelos amaz\u00f3nicos<\/SPAN><\/B>. <\/o:p><\/SPAN><\/P> <\/o:p><\/SPAN><\/P> Juan Jos\u00e9 Ib\u00e1\u00f1ez<\/o:p><\/SPAN><\/B><\/P> <\/o:p><\/SPAN><\/P> In Bacterial Diversity, Amazon Is A ‘Desert’; Desert Is An ‘Amazon’<\/o:p><\/SPAN><\/H1> ScienceDaily (Jan. 25, 2006)<\/FONT><\/EM><\/SPAN><\/SPAN> \u2014 I<\/SPAN>ronically, in the diversity of soil bacteria, the otherwise species-rich Amazon is a more like a desert, while the arid desert is a teeming microbial Amazon, researchers have found. Their first-ever continental-scale genetic survey of soil bacteria revealed that the primary factor that seems to govern the diversity of soil bacteria is soil pH. Thus, the acidic soils of topical forests harbor fewer bacterial species than the neutral soils of deserts. <\/o:p><\/SPAN><\/P><\/DIV>
<\/SPAN><\/DIV> The researchers said that, since <\/SPAN>soil bacteria play a fundamental role in a vast array of ecological processes<\/SPAN><\/B>, their survey constitutes an initial step in a new research pathway to understanding that role. <\/o:p><\/SPAN><\/P> Biologists <\/SPAN>Noah Fierer and Robert Jackson<\/SPAN><\/B> published their findings in the <\/SPAN>Early Online Edition of the Proceedings of the <\/SPAN><\/B>National<\/SPAN><\/B><\/st1:PlaceName> <\/SPAN><\/B>Academy<\/SPAN><\/B><\/st1:PlaceType><\/st1:place> of Sciences the week of <\/SPAN><\/B>Jan. 9, 2006<\/SPAN><\/B><\/st1:date>. Their work was sponsored by the National Science Foundation and the Mellon Foundation. Fierer, a former post-doctoral scientist at <\/SPAN>Duke<\/SPAN><\/st1:PlaceName> <\/SPAN>University<\/SPAN><\/st1:PlaceType><\/st1:place>, is at the <\/SPAN>University<\/SPAN><\/st1:PlaceType> of <\/SPAN>Colorado<\/SPAN><\/st1:PlaceName><\/st1:place>; and <\/SPAN>Jackson<\/SPAN><\/st1:place><\/st1:City> is in the Department of Biology and the <\/SPAN>Nicholas<\/SPAN><\/st1:PlaceName> <\/SPAN>School<\/SPAN><\/st1:PlaceName><\/st1:place> of the Environment and Earth Sciences at Duke. <\/o:p><\/SPAN><\/P> <\/o:p><\/SPAN><\/P> \u00abAlthough soil bacteria have been studied for centuries, fundamental biological questions remain unanswered,\u00bb said Fierer. \u00abWe probably know more about the organisms in the deepest ocean trenches than we know about the organisms living in soil<\/B> i<\/SPAN>n our backyards. <\/SPAN> <\/o:p><\/SPAN><\/P> \u00ab<\/SPAN>We step on soil every day, but few people realize that ‘dirt’ supports a complex community of microorganisms that plays a critical role on Earth, he said. \u00ab<\/SPAN>The number of bacterial species in a spoonful of soil is likely to exceed the total number of plant species in all of the <\/SPAN><\/B><\/SPAN>United States<\/SPAN><\/B><\/st1:place><\/st1:country-region>.<\/SPAN><\/B>\u00bb <\/o:p><\/SPAN><\/P> According to <\/SPAN>Jackson<\/SPAN><\/st1:place><\/st1:City>, \u00ab<\/SPAN>Microbes are very important for most of the critical processes in nature<\/SPAN><\/B>. <\/SPAN>They are <\/SPAN>extremely important for the cycles that make nutrients available <\/SPAN>to plants and animals; and for much of the<\/SPAN> <\/SPAN>respiration that returns carbon back to the atmosphere as carbon dioxide. They also give off most of the important trace gases in our atmosphere like methane. \u00ab<\/SPAN>Given this importance, it was really surprising to us that no one had tried to systematically explore the pattern of diversity of soil bacteria on a continent-wide scale<\/SPAN><\/B>
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