{"id":139835,"date":"2011-12-05T15:54:59","date_gmt":"2011-12-05T14:54:59","guid":{"rendered":"http:\/\/www.madrimasd.org\/blogs\/universo\/?p=139835"},"modified":"2011-11-26T15:05:14","modified_gmt":"2011-11-26T14:05:14","slug":"laboreo-erosion-eolica-aspereza-del-suelo-y-calidad-del-aire","status":"publish","type":"post","link":"https:\/\/www.madrimasd.org\/blogs\/universo\/2011\/12\/05\/139835","title":{"rendered":"Laboreo, Erosi\u00f3n E\u00f3lica, Aspereza del Suelo y Calidad del Aire"},"content":{"rendered":"

Las part\u00edculas de polvo erosionadas desde el suelo son un problema<\/strong> <\/span>con vistas a mantener una agricultura sustentable y la calidad del suelo<\/strong><\/span>, pero tambi\u00e9n afectan seriamente a la salud p\u00fablica de los ciudadanos<\/strong><\/span>, como ocurre con las emisiones industriales, de veh\u00edculos, etc. El laboreo sin labranza, as\u00ed como proteger el suelo con los residuos de las cosechas son t\u00e9cnicas sumamente \u00fatiles a la hora de paliar<\/strong> la cantidad emitida a la atm\u00f3sfera de este tipo de part\u00edculas<\/strong> <\/span>diminutas arrancadas del suelo por la erosi\u00f3n e\u00f3lica<\/strong><\/span>. Sin embargo, tal pr\u00e1ctica<\/strong><\/span>, seg\u00fan algunos colegas, no resulta siempre rentable, siendo preciso el uso del arado<\/strong><\/span>. Investigaciones recientes procedentes de EE.UU., dicen haber construido un aparataje de laboreo que reduce tales emisiones de polvo entre un 30-65%, principalmente cuando las parcelas agr\u00edcolas se encuentran en barbecho<\/strong><\/span> (desnudas de cubierta vegetal). M\u00e1s aun, el suelo no resulta volteado, volviendo a dejar los horizontes o capas del suelo, m\u00e1s o menos en su disposici\u00f3n original<\/strong><\/span>. Al parecer, la biolog\u00eda del suelo tampoco se ve afectada, pero si ayuda a erradicar las enfermedades f\u00fangicas, paliando tambi\u00e9n la emisi\u00f3n (p\u00e9rdida) de materia org\u00e1nica particulada hacia la atm\u00f3sfera<\/span><\/strong>, que de acuerdo a los autores se aproxima al 10% del\u00a0total exportado (aunque esta vez no en forma de CO2) en los predios estudiados. Obviamente, tal modo de proceder evita o recupera la perniciosa compactaci\u00f3n<\/strong> <\/span>de los cm. superficiales del suelo (con independencia de que fuera generada por la maquinaria agr\u00edcola, el impacto de las gotas de lluvia, etc. \u2013es decir se eliminan los sellos y costras<\/strong><\/span>, aunque personalmente albergo m\u00e1s dudas acerca de las que se ubican\u00a0a mayor profundidad \u2013suela de laboreo- inducida por el peso del utillaje muy pesado). En todo este proceso interviene la rugosidad del suelo, de tal forma que cuanto mayor sea esta, tanto menor resultara la p\u00e9rdida de las part\u00edculas finas arrancadas del medio ed\u00e1fico<\/strong><\/span>. \u00a0Sin embargo, otros factores determinantes que colaboran a paliar el problema resultan ser una buena agregaci\u00f3n de las part\u00edculas del suelo<\/strong><\/span>, as\u00ed como la propia humedad que atesore el medio ed\u00e1fico<\/strong><\/span> cuando arrecian vientos de gran intensidad.<\/p>\n

\"wind_erosion_bgr_big\"\u00a0<\/p>\n

Emisi\u00f3n de part\u00edculas finas de polvo en suelos bajo barbecho. Fuente. Portland State University <\/a><\/p>\n

<\/p>\n

Los habitantes de Madrid sufrimos durante algunos a\u00f1os una enorme cantidad de emisiones de part\u00edculas generadas por las obras p\u00fablicas encaminadas a la creaci\u00f3n de las infraestructuras requeridas para acceder a la \u00a0fallida candidatura de esta ciudad, como sede de los Juegos ol\u00edmpicos. Ahora volvemos a presentarnos, pero ese es otro asunto del que prefiero no hablar. En cualquier caso, estas part\u00edculas, procedan de donde procedan <\/span><\/strong>(si bien unas resultan ser m\u00e1s perjudiciales que otras) da\u00f1an la salud de las personas con problemas respiratorios y al\u00e9rgicos<\/strong><\/span>. Sin embargo, en cuanto a la agricultura concierne, tambi\u00e9n perjudican a la calidad del suelo<\/strong><\/span>. No debe extra\u00f1ar pues que ciertas investigaciones se encaminen a paliar tales problemas agron\u00f3micos, ambientales y sanitarios<\/strong><\/span>. \u00a0<\/p>\n

En una de las notas de prensa, tambi\u00e9n se nos informa de que los microorganismos exportados junto a estas part\u00edculas permiten trazar el origen del polvo que alberga la atm\u00f3sfera en un determinado momento y lugar.<\/p>\n

Comentario del Blogger<\/strong><\/span>: \u00a1Curioso!. Busco en Internet la nota de prensa en ingl\u00e9s del Noticiero ARS y me encuentro con una narraci\u00f3n completamente distinta a la que editan en espa\u00f1ol-castellano. Sin embargo, detecto, al\u00a0 mismo tiempo, que la que traduce a nuestra lengua el ARS es casi id\u00e9ntica de la que en su d\u00eda publico Sciencedaily \u00bf?. \u00a0\u00a0\u00a0\u00a0<\/p>\n

\u00a0\"undercutting-tillage\"<\/p>\n

Maquinaria de la que se habla en el texto. Fuente: Ontario Ministry of Agriculture, Food and Rural Affairs<\/a><\/p>\n

Noticiero ARS: Investigadores examinan manera de reducir las emisiones de polvo desde el suelo<\/strong><\/span><\/h3>\n

Por Don Comis<\/a>14 de julio de 2011; Hay una manera muy eficaz de reducir las emisiones de polvo en las partes m\u00e1s \u00e1ridas<\/strong> de la regi\u00f3n de la meseta de Columbia en el Pac\u00edfico-Noroeste de EE.UU., seg\u00fan un cient\u00edfico del Servicio de Investigaci\u00f3n Agr\u00edcola<\/a> (ARS).<\/p>\n

Brenton Sharratt<\/a>, quien es l\u00edder de la Unidad de Investigaci\u00f3n del Manejo de Tierra y la Conservaci\u00f3n de Agua<\/a> mantenida por el ARS en Pullman, Washington, descubri\u00f3 que cortar debajo de la superficie del suelo es una t\u00e9cnica prometedora de la labranza de conservaci\u00f3n en los campos en barbecho<\/strong>. ARS es la agencia principal de investigaciones cient\u00edficas del Departamento de Agricultura de EE.UU.<\/a> (USDA por sus siglas en ingl\u00e9s).<\/p>\n

El aparato usado para cortar debajo de la superficie del suelo tiene <\/strong>cuchillas anchas en forma de V que se solapan. Cuando tiradas por tractor, estas cuchillas cortan debajo de la superficie del suelo y suavemente levantan y devuelven la capa m\u00e1s alta del suelo. Este proceso corta las ra\u00edces de las malezas sin invertir el suelo<\/strong>.<\/p>\n

Las part\u00edculas de suelo en el viento y las part\u00edculas de materia con un di\u00e1metro de menos de 10 micrones, conocidas como PM10, son preocupaciones principales sobre la calidad del aire en<\/strong> la regi\u00f3n del Pac\u00edfico-Noroeste y otras partes de EE.UU. Los experimentos de Sharratt muestran que cortar debajo de la superficie del suelo a una profundidad de cuatro pulgadas puede reducir las emisiones de PM10 del 30 por ciento al 70 por ciento comparado con la labranza convencional<\/strong>. Las tormentas de polvo tambi\u00e9n reducen la productividad de las granjas<\/strong>.<\/p>\n

Cortar debajo de la superficie del suelo es una de muchas pr\u00e1cticas posibles que est\u00e1n siendo identificadas por Sharratt como m\u00e9todos econ\u00f3micos de reducir la erosi\u00f3n e\u00f3lica <\/strong>en la regi\u00f3n de la meseta de Columbia. Las elecciones de cultivos y de m\u00e9todos de labranza influyen en la aspereza del suelo, el tama\u00f1o de los tepes, y la cantidad de residuos de cultivos despu\u00e9s de la cosecha. Con una superficie del suelo m\u00e1s aspereza<\/strong>, los tepes m\u00e1s grandes y una cantidad m\u00e1s grande de residuos de cultivos, hay menos susceptibilidad del suelo a la erosi\u00f3n causada por el viento o el agua<\/strong>. Sharratt descubri\u00f3 que la pr\u00e1ctica de cortar debajo de la superficie del suelo crea una superficie del suelo m\u00e1s aspereza aerodin\u00e1micamente y promueve la retenci\u00f3n de los residuos de cultivos<\/strong>.<\/p>\n

Lea m\u00e1s<\/a> sobre esta investigaci\u00f3n, la cual apoya la prioridad del USDA de promover la agricultura sostenible, en la revista ‘Agricultural Research’ de julio del 2011.<\/p>\n

Sharratt y su colega Guanglong Feng, quien trabaja en el Departamento de Ingenier\u00eda de Sistemas Biol\u00f3gicos<\/a> de la Universidad Estatal de Washington<\/a> en Pullman, han publicado art\u00edculos sobre esta investigaci\u00f3n en las revistas ‘Soil and Tillage Research<\/a>‘ (Investigaciones sobre el Suelo y la Labranza) y ‘Earth Surface Processes and Landforms<\/a>‘ (Procesos de la Superficie del Suelo y Formas de Terreno).<\/p>\n

Nota de Prensa Original en Ingl\u00e9s<\/strong><\/span><\/p>\n

Pacific Northwest Farmers Can See Soil Blow Away<\/a><\/strong><\/h3>\n

EPA\u2019s regulations on PM2.5 and PM10 affect every aspect of agriculture, not only cotton gins but also cattle feedlots and farming operations.<\/p>\n

For the Columbia Plateau region of the Pacific Northwest, the focus is on topsoil blowing in the wind: The smaller particles occasionally contribute to poor air quality in the region<\/strong>.<\/p>\n

Farmers in this wind-erosion-prone region are as anxious as any others about the prospect of farms being regulated like cotton gins and other industries, with fears of urban air-pollution samplers surrounding their farmland. But they also want their rich topsoil to stay in place, so they are eager to reduce wind erosion<\/strong>.<\/p>\n

Brenton Sharratt and Ann Kennedy, at the ARS Land Management and Water Conservation Research Unit in Pullman, Washington, are identifying practices that will keep the soil from blowing away.<\/p>\n

Sharratt, research leader of the unit, examines the physical properties, and Kennedy, a soil scientist, studies the biological properties of soils that affect wind erosion<\/strong>.<\/p>\n

Sharratt measures the quantity and size of soil particles blown off fields while Kennedy analyses the soil for its lipid content from the microbes living in the soil. Each microbe community has a unique fingerprint that can be used to identify the soil<\/strong>. Sediment deposited far downwind of a field can potentially be traced back to where it blew from<\/strong>.<\/p>\n

Although she and Sharratt focus on soils of the Columbia Plateau region in parts of Idaho, Oregon, and Washington State, Kennedy also works with ARS scientists in Colorado, Idaho, Missouri, and Texas on fingerprinting soils<\/strong>. The scientists exchange soil samples to study a variety of soils from different regions. Interestingly, microbial communities from dirt and gravel roads differed from adjacent agricultural soils<\/strong> whether in Washington or Texas.<\/p>\n

\u201cApparently, the microbial communities found on roads change with time because of the lack of plants and restricted water infiltration<\/strong>,\u201d Kennedy says.<\/p>\n

They collect samples from devices that trap blowing soil particles; these devices were invented by ARS scientists in Lubbock.<\/p>\n

Sharratt is investigating how soil and crop management affects the amount of soil and PM10 eroded from fields during high winds<\/strong>. Tillage and crops can influence soil roughness, soil aggregation (or size of soil clods), and the quantity of crop residue on the soil surface. All these factors affect the soil\u2019s susceptibility to erosion by wind or water. He is also looking at how soil moisture and crusting can protect the soil from wind erosion<\/strong>.<\/p>\n

\u201cMaintaining roughness and nonerodible material such as crop residue on the soil surface is key to controlling wind erosion<\/strong>\u201d Sharratt says. \u201cWe\u2019re looking for ways to manage soils that minimize blowing and are cost effective for the farmer.\u201d<\/p>\n

Ultimately, Sharratt, Kennedy, and their colleagues are looking for management practices that reduce the soil\u2019s vulnerability to wind erosion. They know that no-till\u2014eliminating plowing or frequent tillage before planting, leaving adequate amounts of protective residue from previous crops on the surface\u2014is very effective at reducing wind erosion and PM10 emissions from agricultural lands. But no-till is often not economically viable in the very driest parts<\/strong> of the Columbia Plateau. There are challenges yet to be worked out before no-till systems can be used with success <\/strong>throughout the region.<\/p>\n

One tillage technique that seems promising is undercutting, which slices beneath the soil surface and gently lifts and sets down the uppermost layer of soil in place. Undercutting severs the roots of weeds without inverting the soil as a plow does<\/strong>.<\/p>\n

\u201cUndercutting has reduced soil and PM10 loss from fields during high wind events by as much as 65 percent as compared to conventional tillage practices in the drier parts of the region<\/strong>,\u201d Sharratt says. \u201cThis breaks open compacted layers and breaks up harmful fungi, while leaving the soil and organic matter intact, with positive effects on beneficial microbes<\/strong>,\u201d Kennedy says.<\/p>\n

\u201cWe always thought that most of the carbon that makes up organic matter was lost to the atmosphere as carbon dioxide,\u201d Kennedy says. \u201cBut we have found that a lot of organic matter is actually being lost to the wind as soil blows off a farm field, as much as 10 percent of total organic matter losses<\/strong>. This is one more incentive, as though any were needed, for farmers to keep the soil in place<\/strong>.<\/p>\n

\u201d\u2014By Don Comis,<\/strong><\/a> Agricultural Research Service Information Staff.<\/p>\n

This research supports the USDA priority of responding to climate change and is part of Climate Change, Soils, and Emissions (#212), an ARS national program described at <\/em>www.nps.ars.usda.gov<\/a><\/em>.<\/em><\/p>\n

To reach scientists mentioned in this story, contact <\/em>Don Comis<\/a><\/em>, USDA-ARS <\/em>Information Staff<\/a><\/em>, 5601 Sunnyside Ave., Beltsville, MD 20705-5129; (301) 504-1625.<\/em><\/p>\n

Nota de Prensa en ScienceDaily<\/strong><\/span><\/p>\n

Dust Storms: New Way to Undercut Dust Emissions<\/a><\/h3>\n

ScienceDaily (July 14, 2011) <\/strong><\/span>\u2014 There is literally a way to undercut dust emissions in the very driest parts of the Pacific Northwest’s Columbia Plateau region, according to a U.S. Department of Agriculture (USDA) scientist.<\/p>\n

Brenton Sharratt, research leader at the USDA Agricultural Research Service (ARS) Land Management and Water Conservation Research Unit in Pullman, Wash., found that undercutting is a promising conservation tillage technique on fallow fields. ARS is USDA’s principal intramural scientific research agency.<\/p>\n

An undercutter has wide, overlapping, V-shaped steel blades. Pulled by a tractor, the blades slice beneath the soil surface and gently lift and set down the uppermost layer in place. This severs weed roots without inverting the soil as a plow does.<\/p>\n

Wind-blown soil particles or particulate matter less than 10 microns in diameter, known as PM10, are an air quality concern<\/strong> in the Pacific Northwest and other parts of the United States. Sharratt’s experiments show that undercutting to a depth of 4 inches can reduce PM10 emissions by 30 to 70 percent compared to conventional tillage<\/strong>. Dust storms also harm farm productivity.<\/p>\n

Undercutting is one of many possible practices being identified by Sharratt as cost-effective ways to reduce wind erosion in the Columbia Plateau region. Both tillage and crop choices influence soil roughness, the size of soil clods, and the amount of post-harvest crop residue<\/strong>. The rougher the soil surface, the bigger the clods, and the more residue, the less susceptible the soil is to erosion by wind or water<\/strong>. Sharratt found that undercutter tillage creates an aerodynamically rougher soil surface and promotes retention of crop residue.<\/p>\n

Read more about this research, which supports the USDA commitment to sustainable agriculture, in the July 2011 issue of Agricultural Research magazine.<\/p>\n

Sharratt and Guanglong Feng, with Washington State University’s Department of Biological Systems Engineering at Pullman, have published pioneering papers on this subject in the journals Soil & Tillage Research and Earth Surface Processes and Landforms.<\/p>\n

Blowing in the Wind<\/a><\/h3>\n

Unless, perhaps, someone in our family has a dust allergy<\/strong>, most of us probably don\u2019t think much about dust. And if we do, we probably think about the dust on our coffee tables.<\/p>\n

Dust, however, isn\u2019t just in our houses. It\u2019s everywhere and can affect our health<\/strong>. And all dust is not created equal: The smaller particles, which are more difficult to see, are potentially the most dangerous<\/strong>.<\/p>\n

In 2006, the U.S. Environmental Protection Agency (EPA) lowered the limit on average PM2.5 emissions over a 24-hour period from 65 to 35 micrograms per cubic meter. Some states have set the standard much lower. This comes from a growing concern that the smallest dust particles pose the biggest health threat<\/strong>, because they are small enough to penetrate deeply into peoples\u2019 lungs.<\/p>\n

\u201cPM2.5\u201d refers to particulate matter less than 2.5 microns in diameter<\/strong>\u20142.5 microns is about 1\/30th the thickness of a human hair<\/strong>.<\/p>\n

As states implement required plans to achieve federal standards\u2014or even stricter ones\u2014and begin to regulate various types of industries, they face the problem of a scarcity or, in some cases, a lack of data on how much PM2.5 those industries currently emit<\/strong>.<\/p>\n

In the case of agricultural operations, EPA and the<\/strong> Agricultural Research Service<\/a> are working together with<\/strong> the industries and the states to develop better science-based information and methods to set standards.<\/p>\n","protected":false},"excerpt":{"rendered":"

Las part\u00edculas de polvo erosionadas desde el suelo son un problema con vistas a mantener una agricultura sustentable y la calidad del suelo, pero tambi\u00e9n afectan seriamente a la salud p\u00fablica de los ciudadanos, como ocurre con las emisiones industriales, de veh\u00edculos, etc. El laboreo sin labranza, as\u00ed como proteger el suelo con los residuos de las cosechas son t\u00e9cnicas sumamente \u00fatiles a la hora de paliar la cantidad emitida a la atm\u00f3sfera de este tipo de part\u00edculas diminutas arrancadas del suelo por la erosi\u00f3n e\u00f3lica. Sin embargo, tal pr\u00e1ctica, seg\u00fan algunos colegas, no resulta siempre rentable, siendo preciso el\u2026<\/p>\n","protected":false},"author":26,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"ngg_post_thumbnail":0},"categories":[594,613,589,592,585],"tags":[2838,46691,47082,2518,9190,46745],"blocksy_meta":{"styles_descriptor":{"styles":{"desktop":"","tablet":"","mobile":""},"google_fonts":[],"version":4}},"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/www.madrimasd.org\/blogs\/universo\/wp-json\/wp\/v2\/posts\/139835"}],"collection":[{"href":"https:\/\/www.madrimasd.org\/blogs\/universo\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.madrimasd.org\/blogs\/universo\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.madrimasd.org\/blogs\/universo\/wp-json\/wp\/v2\/users\/26"}],"replies":[{"embeddable":true,"href":"https:\/\/www.madrimasd.org\/blogs\/universo\/wp-json\/wp\/v2\/comments?post=139835"}],"version-history":[{"count":9,"href":"https:\/\/www.madrimasd.org\/blogs\/universo\/wp-json\/wp\/v2\/posts\/139835\/revisions"}],"predecessor-version":[{"id":140902,"href":"https:\/\/www.madrimasd.org\/blogs\/universo\/wp-json\/wp\/v2\/posts\/139835\/revisions\/140902"}],"wp:attachment":[{"href":"https:\/\/www.madrimasd.org\/blogs\/universo\/wp-json\/wp\/v2\/media?parent=139835"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.madrimasd.org\/blogs\/universo\/wp-json\/wp\/v2\/categories?post=139835"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.madrimasd.org\/blogs\/universo\/wp-json\/wp\/v2\/tags?post=139835"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}