Posted on Categories Agriculture/Food System, Climate Change & Energy, Sustainable LivingTags , , , , Leave a comment on Compost helps rangeland lock up carbon

Compost helps rangeland lock up carbon

The rolling green pastures west of Petaluma where Hank Corda stood last week in blue jeans and a camouflage ball cap are not an obvious location to mount a worldwide offensive against climate change.
No factories billow smoke on the 850-acre ranch that’s been in Corda’s family for a century, nor do many vehicles traverse the narrow road. One might surmise the only gross polluters here are the black-and-white dairy cows that graze the property.
In fact, rangelands are a major source of carbon loss through the farming techniques used for harvesting and soil management. A major key to solving the problem, researchers contend, is in the soil on a hillside below Corda’s ranch home.
There, workers dumped compost made of manure and green landscape waste to trap carbon dioxide in the ground and also absorb it from the air. The ranch, which is at the head of San Antonio Creek, is one of three test sites for a novel “carbon-farming” program that researchers say could dramatically lower greenhouse-gas emissions and blunt the effects of climate change, but only if it can be replicated on a mass scale.
The Marin Carbon Project has drawn attention from scientists around the world and, closer to home, from agricultural producers in neighboring counties. It has also caught the attention of Sacramento lawmakers, including Assemblyman Marc Levine, D-San Rafael, who was expected to introduce legislation Monday to expand the program in California.
Advocates say if compost was applied to just 5 percent of California’s grazing lands, the soil could capture a year’s worth of greenhouse gas emissions from the state’s farm and forestry industries.
Read more via Cleaning up with compost | The Press Democrat.

Posted on Categories Climate Change & Energy, ForestsTags , Leave a comment on Tree growth never slows : Biggest trees accumulate more carbon than younger siblings

Tree growth never slows : Biggest trees accumulate more carbon than younger siblings

conifersJeff Tollefson, NATURE
Many foresters have long assumed that trees gradually lose their vigour as they mature, but a new analysis suggests that the larger a tree gets, the more kilos of carbon it puts on each year.
“The trees that are adding the most mass are the biggest ones, and that holds pretty much everywhere on Earth that we looked,” says Nathan Stephenson, an ecologist at the US Geological Survey in Three Rivers, California, and the first author of the study, which appears today in Nature1. “Trees have the equivalent of an adolescent growth spurt, but it just keeps going.”
The scientific literature is chock-full of studies that focus on forests’ initial growth and their gradual move towards a plateau in the amount of carbon they store as they reach maturity2. Researchers have also documented a reduction in growth at the level of individual leaves in older trees3.
In their study, Stephenson and his colleagues analysed reams of data on 673,046 trees from 403 species in monitored forest plots, in both tropical and temperate areas around the world. They found that the largest trees gained the most mass each year in 97% of the species, capitalizing on their additional leaves and adding ever more girth high in the sky.
via Tree growth never slows : Nature News & Comment.