CIRS Blog about Rural California
It’s been a quarter century since government regulations limiting emissions of sulfur and nitrogen oxides from coal-fired power plants began to neutralize the problem of acid rain, but lakes in the northeastern U.S. and eastern Canada have been sluggish to recover.
Scientists have linked the delayed comeback to a lack of acid-buffering calcium in surrounding soils, which continued to acidify despite cuts in pollutants. Now, however, a study shows for the first time that soil acidification has begun to reverse across a broad swath from western Ontario to Maine (Environ. Sci. Technol. 2015, DOI:10.1021/acs.est.5b02904). Researchers hope improvements to forest health and lake water quality will follow.
To read the remainder of the article that originally appeared on the Chemical & Engineering News website Nov. 6. visit: http://cen.acs.org/articles/93/web/2015/11/Soils-Damaged-Acid-Rain-Begin.html
Carbon Sequestration in Grazing Land Ecosystems1
Maria Silveira, Ed Hanlon, Mariana Azenha, and Hiran M. da Silva2
This publication provides basic information about the important role of native and improved pastures (referred to as grazing land) in sequestering carbon from the atmosphere. Because of the relatively high sequestration rates and extensive area, grazing land represents an important component of terrestrial carbon dioxide (CO2) offset and is a significant sink for long-term carbon sequestration and greenhouse gas mitigation. This publication contains information for stakeholders, students, scientists, and environmental agencies interested in enhancing ecosystems services provided by grazing lands.
Global Carbon Cycle
The global carbon cycle consists of complex processes that control the movement of carbon between the atmosphere, land, and oceans. Although natural processes dominate the carbon cycle, human-induced activities can also alter these carbon transfers. In the atmosphere, carbon is mainly present as carbon dioxide (CO2). Large amounts of carbon are also present in the soil, primarily as soil organic matter. Soil organic matter plays a key role in determining soil quality and its potential to produce food, fiber, and fuel. During the past two decades, the global carbon cycle has received significant attention because of its role in global climate change.
Two important global topics are the rising atmospheric CO2 concentrations caused by human-induced activities (primarily combustion of fossil fuels) and the potential effects on climate change. In addition to CO2, increased atmospheric concentrations of nitrous oxides (N2O and NO) and methane (CH4) are also believed to cause global warming. Carbon dioxide, nitrous oxides, and methane (also known as greenhouse gases) can trap heat in the atmosphere and contribute to global warming. Levels of several important greenhouse gases have increased by 25% since large-scale industrialization began approximately 150 years ago, and this increase is primarily caused by energy use.
Plants remove carbon from the atmosphere during photosynthesis, a process done without human intervention. However, to address the contributions made by humans, the carbon must be stored or sequestered. Typically, carbon in plants undergoes several conversions. Some conversions are rapid, such as the addition of fresh plant material to the soil, while others may take long periods of time. For example, a large amount of carbon is already sequestered in our soil.
The latest episode of the Thrive podcast takes a close look at the ground beneath our feet. Soil, on which terrestrial life depends, is often ignored precisely because it is everywhere and yet invisible. Healthy soils contribute so much to human well-being, from nutritious food to clean water, and yet the soils of more than a fifth of all cropland, pasture, forest and woodland are degraded to some extent. Degraded soils, apart from being unable to meet the needs of the people who depend on them, also emit large amounts of greenhouse gasses, contributing to climate change.
How, then, can we best restore degraded soils? Sessions at Global Soil Week 2015 in Berlin, co-organized by the Water, Land and Ecosystems research program of CGIAR, provided a platform for people to share different approaches, each of which has something to offer.
Humankind is faced with the continuing challenge of sustainably growing sufficient food to feed an ever-growing population. The United Nations Food and Agricultural Organization  citing a United Nations World Population Prospects report predicts that the earth’s population will reach 9.1 billion by the middle of this century.
Much of this growth will be in nations whose populations now suffer from malnutrition or outright starvation. In addition to a growing population, the increase in people will demand more food, more meat, and higher quality food because it will be more urban and wealthier according to FAO. Their estimate is that increased demand will require current food production to rise by 60 percent.
The challenge becomes more acute when it is understood that the land area for growing food is not expanding. Indeed, urban growth onto farmland and loss of arable (farmable) soil by wind and water erosion are reducing the available land area most suitable for farming. More land can be brought into production, but with a potentially high environmental and monetary cost.