Saltar para: Posts [1], Pesquisa e Arquivos [2]

Release No. 0323.10
USDA Office of Communications (202) 720-4623
Unprecedented Cropland Study Confirms Conservation Practices Work On Farms in Upper Mississippi River Basin
Targeted Conservation Treatment Will Enable Greater Environmental Gains

WASHINGTON, June 16, 2010 - Conservation practices installed and applied by agricultural producers on cropland are reducing sediment, nutrient and pesticide losses from farm fields, Agriculture Secretary Tom Vilsack said today as he announced the release of a comprehensive study on the effects of conservation practices on environmental quality in the Upper Mississippi River Basin (UMRB).

"This important new report confirms that farmers and ranchers are stepping up and implementing conservation practices that can and do have a significant impact on the health of America's soil and water," Vilsack said. "The information gathered for this study will make it possible to quantify the effectiveness of conservation practices for the first time and enable USDA to design and implement conservation programs that will not only better meet the needs of farmers and ranchers, but also help ensure that taxpayers' conservation dollars are used as effectively as possible."


Key findings from the study, "Effects of Conservation Practices on Cultivated Cropland in the Upper Mississippi River Basin" include the following:


  • Suites of practices work better than single practices;
  • Targeting critical acres improves effectiveness significantly; practices have the greatest effect on the most vulnerable acres, such as highly erodible land and soils prone to leaching;
  • Uses of soil erosion control practices are widespread in the basin. Most acres receive some sort of conservation treatment, resulting in a 69 percent reduction in sediment loss. However, about 15 percent of the cultivated cropland acres still have excessive sediment losses and require additional treatment;
  • The most critical conservation concern in the region is the loss of nitrogen from farm fields through leaching, including nitrogen loss through tile drainage systems.

The study also revealed opportunities for improving the use of conservation practices on cropland to enhance environmental quality. For instance, the study found that consistent use of nutrient management (proper rate, form, timing and method of application) is generally lacking throughout the region. Improved nutrient management would reduce the risk of nutrient movement from fields to rivers and streams. A suite of practices that includes both soil erosion and consistent nutrient management is required to simultaneously address soil erosion and nitrogen leaching loss.

This study is part of a larger effort - the Conservation Effects Assessment Project (CEAP) - to assess the effects of conservation practices on the nation's cropland, grazing lands, wetlands, wildlife and watersheds. CEAP is a multi-agency, multi-resource effort led by USDA's Natural Resources Conservation Service (NRCS). Additional regional cropland studies on the effects of conservation practices will be forthcoming over the next several months.

The complete UMRB cropland study report can be found at

Key partners in this study were USDA's Agricultural Research Service and Texas AgriLife Research, part of the Texas A&M University system.

The UMRB covers about 190,000 square miles-121.5 million acres-between north-central Minnesota and the confluence of the Mississippi and Ohio rivers. The basin includes large portions of Illinois, Iowa, Minnesota, Missouri, Wisconsin and small portions of Indiana, Michigan and South Dakota. Nearly half the basin is planted in corn and soybeans.

NRCS is celebrating 75 years helping people help the land in 2010. Since 1935, the NRCS conservation delivery system has advanced a unique partnership with state and local governments and private landowners delivering conservation based on specific, local conservation needs, while accommodating state and national interests. President Franklin Roosevelt created the Soil Conservation Service, now known as NRCS, on April 27, 1935 to help farmers and ranchers overcome the devastating effects of drought, especially in the Midwest and Northern Plains regions.

Please download PowerPoint Presentation

USDA is an equal opportunity provider, employer and lender. To file a complaint of discrimination, write: USDA, Director, Office of Civil Rights, 1400 Independence Ave., S.W., Washington, D.C. 20250-9410 or call (800) 795-3272 (voice) or (202-720-6382 (TDD).


Autoria e outros dados (tags, etc)

Relatório de Actividades de 2009

por papinto, em 16.06.10

Autoria e outros dados (tags, etc)



Increased yields of crops -- such as this maize in Kenya -- have not only helped feed the world, but have reduced greenhouse gas emissions. (Credit: Marshall Burke)

ScienceDaily (June 14, 2010) — Advances in high-yield agriculture over the latter part of the 20th century have prevented massive amounts of greenhouse gases from entering the atmosphere -- the equivalent of 590 billion metric tons of carbon dioxide -- according to a new study led by two Stanford Earth scientists.

The yield improvements reduced the need to convert forests to farmland, a process that typically involves burning of trees and other plants, which generates carbon dioxide and other greenhouse gases.

The researchers estimate that if not for increased yields, additional greenhouse gas emissions from clearing land for farming would have been equal to as much as a third of the world's total output of greenhouse gases since the dawn of the Industrial Revolution in 1850.

The researchers also calculated that for every dollar spent on agricultural research and development since 1961, emissions of the three principal greenhouse gases -- methane, nitrous oxide and carbon dioxide -- were reduced by the equivalent of about a quarter of a ton of carbon dioxide -- a high rate of financial return compared to other approaches to reducing the gases.

"Our results dispel the notion that modern intensive agriculture is inherently worse for the environment than a more 'old-fashioned' way of doing things," said Jennifer Burney, lead author of a paper describing the study that will be published online by the Proceedings of the National Academy of Sciences.

Adding up the impact

The researchers calculated emissions of carbon dioxide, methane and nitrous oxide, converting the amounts of the latter two gases into the quantities of carbon dioxide that would have an equivalent impact on the atmosphere, to facilitate comparison of total greenhouse gas outputs.

Burney, a postdoctoral researcher with the Program on Food Security and the Environment at Stanford, said agriculture currently accounts for about 12 percent of human-caused greenhouse gas emissions. Although greenhouse gas emissions from the production and use of fertilizer have increased with agricultural intensification, those emissions are far outstripped by the emissions that would have been generated in converting additional forest and grassland to farmland.

"Every time forest or shrub land is cleared for farming, the carbon that was tied up in the biomass is released and rapidly makes its way into the atmosphere -- usually by being burned," she said. "Yield intensification has lessened the pressure to clear land and reduced emissions by up to 13 billion tons of carbon dioxide a year."

"When we look at the costs of the research and development that went into these improvements, we find that funding agricultural research ranks among the cheapest ways to prevent greenhouse gas emissions," said Steven Davis, a co-author of the paper and a postdoctoral researcher at the Carnegie Institution at Stanford.

To evaluate the impact of yield intensification on climate change, the researchers compared actual agricultural production between 1961 and 2005 with hypothetical scenarios in which the world's increasing food needs were met by expanding the amount of farmland rather than by the boost in yields produced by the Green Revolution.

"Even without higher yields, population and food demand would likely have climbed to levels close to what they are today," said David Lobell, also a coauthor and assistant professor of environmental Earth system science at Stanford.

"Lower yields per acre would likely have meant more starvation and death, but the population would still have increased because of much higher birth rates," he said. "People tend to have more children when survival of those children is less certain."

Avoiding the need for more farmland

The researchers found that without the advances in high-yield agriculture, several billion additional acres of cropland would have been needed.

Comparing emissions in the theoretical scenarios with real-world emissions from 1961 to 2005, the researchers estimated that the actual improvements in crop yields probably kept greenhouse gas emissions equivalent to at least 317 billion tons of carbon dioxide out of the atmosphere, and perhaps as much as 590 billion tons.

Without the emission reductions from yield improvements, the total amount of greenhouse gas pumped into the atmosphere over the preceding 155 years would have been between 18 and 34 percent greater than it has been, they said.

To calculate how much money was spent on research for each ton of avoided emissions, the researchers calculated the total amount of agricultural research funding related to yield improvements since 1961 through 2005. That produced a price between approximately $4 and $7.50 for each ton of carbon dioxide that was not emitted.

"The size and cost-effectiveness of this carbon reduction is striking when compared with proposed mitigation options in other sectors," said Lobell. "For example, strategies proposed to reduce emissions related to construction would cut emissions by a little less than half the amount that we estimate has been achieved by yield improvements and would cost close to $20 per ton."

The authors also note that raising yields alone won't guarantee lower emissions from land use change.

"It has been shown in several contexts that yield gains alone do not necessarily stop expansion of cropland," Lobell said. "That suggests that intensification must be coupled with conservation and development efforts.

"In certain cases, when yields go up in an area, it increases the profitability of farming there and gives people more incentive to expand their farm. But in general, high yields keep prices low, which reduces the incentive to expand."

The researchers concluded that improvement of crop yields should be prominent among a portfolio of strategies to reduce global greenhouse gases emissions.

"The striking thing is that all of these climate benefits were not the explicit intention of historical investments in agriculture. This was simply a side benefit of efforts to feed the world," Burney noted. "If climate policy intentionally rewarded these kinds of efforts, that could make an even bigger difference. The question going forward is how climate policy might be designed to achieve that."

Email or share this story:

Story Source:

The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by Stanford University. The original article was written by Louis Bergeron.

Autoria e outros dados (tags, etc)

New UN science body to monitor biosphere

por papinto, em 13.06.10

'IPCC for biodiversity' approved after long negotiation

Representatives from close to 90 countries gathering in Busan, Korea, this week, have approved the formation of a new organization to monitor the ecological state of the planet and its natural resources. Dubbed the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES), the new entity will likely meet for the first time in 2011 and operate much like the Intergovernmental Panel on Climate Change (IPCC).

In essence, that means the IPBES will specialize in "peer review of peer review", says Nick Nuttall, a spokesman for the United Nations Environment Programme, which has so far hosted the IPBES birth process. Its organizers hope that its reports and statements will be accepted as authoritative and unbiased summaries of the state of the science. Like the IPCC, it will not recommend particular courses of action. "We will not and must not be policy prescriptive", emphasized Robert Watson, chief scientific advisor to the UK's Department for Environment, Food and Rural Affairs and a vice-chair of the Busan meeting. "That is critical, or it will kill the process."

According to the document approved June 11, IPBES will conduct periodic assessments of the diversity of life on earth and its 'ecosystem services'—those outputs of ecosystems, such as clean fresh water, fish, game, timber and a stable climate, that benefit humankind. These assessments will answer questions about how much biodiversity is declining and what the implications of extinctions and ecosystem change are for humanity. Assessments will take place on global, regional and sub-regional scales.

“There was concern... that this not become a huge bureaucracy.”

Nick Nuttall
United Nations Environment Programme

IPBES will also take a hand in training environmental scientists in the developing world, both with a to-be-determined budget of its own and by alerting funders about gaps in global expertise. The organization will also identify research that needs to be done and useful tools—such as models—for policymakers looking to apply a scientific approach to such decisions as land management.

In Busan, negotiations stretched late into the night as delegates debated the scope of the proposed IPBES, including the specifics of how it will be funded. "There was concern among the developed countries that this not become a huge bureaucracy," says Nuttall. "Governments wanted to be reassured that it would be lean and mean and streamlined."

Another bone of contention was to what extent IPBES would tackle emerging issues or areas of contested science. In the end, it was agreed that the body will draw attention to "new topics" in biodiversity and ecosystem science. "If there had been something like this before, then new results on issues such as ocean acidification, dead zones in the ocean and the biodiversity impacts of biofuels would have been rushed to the inboxes of policymakers, instead of coming to their attention by osmosis," says Nuttall.

Among the governments who assented to the IPBES's creation were the European Union, the United States, and Brazil. The plan will come before the general assembly of the United Nations, slated to meet in September, for official approval. Those involved with the process say that that the UN creation of the new body is a virtual certainty.

Autoria e outros dados (tags, etc)

Chave para a crise

por papinto, em 13.06.10

Uma das chaves para a crise! Valores, atitudes e padrões comportamento:



  • Facilitismo        Exigência
  • Vulgaridade      Excelência
  • Moleza             Dureza
  • Golpada           Seriedade
  • Videirismo        Honra
  • Ignorância        Conhecimento
  • Mandriice          Trabalho
  • Aldrabice           Honestidade

(Ernâni Lopes, Plano Inclinado, SIC Notícias, 12-06-2010)

Autoria e outros dados (tags, etc)

Que hace el inginiero agrónomo para ti?

por papinto, em 12.06.10

Autoria e outros dados (tags, etc)

Boas notícias

por papinto, em 12.06.10

Plano de austeridade não afecta universidades

por Mariana de Araújo Barbosa, Publicado em 11 de Junho de 2010 no i-online

As universidades nacionais escaparam aos cortes de orçamento impostos pelas medidas incluídas no plano de austeridade do governo. O plano de poupança levado a cabo pelo governo previa a cativação de 20% das receitas com as propinas, mas José Sócrates recuou no plano de austeridade para o Ensino Superior, escreve hoje o Diário Económico.

Com o recuo do executivo, as universidades contam com mais 48 milhões de euros, valor de que o es

Autoria e outros dados (tags, etc)


ScienceDaily (June 9, 2010) — Earth is expected to be home to roughly 9 billion people by 2050 -- and everyone needs to eat. But a new report from the United Nations Environment Programme observes that growing and producing food make agriculture and food consumption among the most important drivers of environmental pressures, including climate change and habitat loss.

The report's lead author is Edgar Hertwich, a Professor of Energy and Process Engineering at the Norwegian University of Science and Technology.

The report, called "Assessing the Environmental Impacts of Consumption and Production: Priority Products and Materials" is the first-ever global-level assessment of the causes of different environmental pressures that result from economic activities. Professor Hertwich, who is director of NTNU's Industrial Ecology Programme, worked with colleagues for two years to develop detailed answers to three interrelated questions:

  • What are the most important industries that cause climate change?
  • How much energy do different consumption activities require when the production of the products is taken into account?
  • What are the materials that contribute most to environmental problems?

Agriculture causes major environmental impacts

Professor Hertwich said he was surprised to find that the environmental impacts of agriculture were greater than the production of materials such as cement and other manufactured goods. While the report does not make specific recommendations for change -- it is instead a detailed description of the problem -- Hertwich says, "it is clear that we can't all have a European average diet -- we just don't have the land and resources for that."

The report itself observes that "impacts from agriculture are expected to increase substantially due to population growth, increasing consumption of animal products. Unlike fossil fuels, it is difficult to look for alternatives: people have to eat. A substantial reduction of impacts would only be possible with a substantial worldwide diet change, away from animal products."

More income, more meat in our diets

Another surprise was the effect of increasing economic affluence on different environmental impacts. The report authors found that environmental impacts increase approximately 80 per cent with the doubling of an individual's income. This increase results in part from a shift to a more meat-intensive diet.

Another related problem -- and another surprise to Hertwich -- was the amount of food waste in both rich and poor countries. "Between 30 and 50 per cent of all food produced is spoiled or wasted," Hertwich said. "It's really quite surprising how much food waste there is." In poor countries, food is spoiled on the way to the market, while in rich countries, it spoils in people's refrigerators, he said.

Hope for the future?

Both Hertwich and international environmental officials say that people and policymakers must face the substantial environmental challenges facing all of humankind. In a press release from the UNEP, Ashok Khosla, co-chair of the Panel and President of the World Conservation Union (IUCN), is quoted as saying: "Incremental efficiency gains in, for example, motor cars or home heating systems have provided some improvements but, faced with the scale of the challenge, far more transformational measures need to be taken-- currently we are fiddling--or fiddling around the edges--while Rome burns."

Hertwich agreed with Khosla's assessment. "There are fundamental challenges out there that I don't think that we as a society have woken up to yet," he said. "Somewhere in our rear-view mirror there is a big monster, and we are pretending it is not there. But I think if we really decide to tackle these challenges we will be able to do so."

Hertwich has also developed a website that enables individuals to look at the Carbon Footprint of Nations ( The report was released to coincide with the UN's Environment Day on June 5.

The report is available at:

Email or share this story:

Story Source:

The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by The Norwegian University of Science and Technology (NTNU).

Autoria e outros dados (tags, etc)

Áreas disciplinares_Prposta Departamentos

Autoria e outros dados (tags, etc)


Taking the guesswork out of soil classification
ScienceDaily (2010-06-07) -- A researcher has developed a technique that uses digital imaging of soil samples to take some of the guesswork out of wetland identification. ... > read full article

Autoria e outros dados (tags, etc)


subscrever feeds