Why Is New York City’s Air Getting Cleaner?

Read the full story at Discover Magazine.

Several weeks ago, this was the headline for a press release:

Mayor Bloomberg announces New York City’s air quality has reached the cleanest levels in more than 50 years.

That’s quite a claim. Most media outlets reporting this story cut and pasted from the press release; few bothered to delve into the report Bloomberg was citing, much less provide any meaningful perspective on its findings. I asked students in my urban environmental journalism class at CUNY to look beyond the headlines and place the story in a larger context. Below are their dispatches.

Dirtball’s ‘Green’ Jeans Are Made In U.S. From Recycled Water Bottles

Read the full story at the Huffington Post.

How do you get more American than blue jeans? How about making them in America, for starters. That’s what the eco-friendly fashion company Dirtball is doing with its new line of denim, which will be made entirely in the USA.

The blue jean has a green twist, as well. Dirtball CEO Joe Fox brags that the jeans are eco-friendly since they’re made out of recycled water bottles (and cotton). The Green Jean just hit its $40,000 funding target on Kickstarter.

Is Biochar a Solution to Climate Change? Maybe, Maybe Not.

Read the full post from the Union of Concerned Scientists.

A new paper published earlier this week in the scientific journal PLoSOne calls into question whether we know enough about biochar to use it as an important strategy to mitigate climate change. The article, two of whose co-authors formerly worked here at UCS, did a systematic review of the scientific literature on biochar through 2011, and found 311 relevant papers.

But even with all this research, a key question remains unanswered: How long does biochar persist in the soil?

The review was originally done last year as a report, partly funded by UCS, which is available on our website. The authors – Noel Gurwick, Lisa Moore, Charlene Kelly, and Pipa Elias – wanted to see if the published science backed up the oft-discussed possibility of making biochar and adding it to soils as a way to reduce greenhouse gas emissions. (For one recent – indeed, still ongoing – discussion, see the American Carbon Registry’s current comment process on a methodology that would allow compensating such projects in a carbon market. The comment period lasts till October 25).

Biochar from Miscanthus: a potential silicon fertilizer

David Houben, Philippe Sonnet, Jean-Thomas Cornelis (2013). “Biochar from Miscanthus: a potential silicon fertilizer.” Plant and Soil, online ahead of print. DOI: 10.1007/s11104-013-1885-8


Background and aims

Silicon (Si) is largely recognized to improve plant growth subjected to various biotic and abiotic stresses. As plants accumulate Si in the form of readily-soluble phytolith, we examine the possibility of using phytolith-rich biochar as a bio-available Si source for increasing the agronomical productivity of Si high-accumulator plants while augmenting soil fertility and C sequestration.


By adding three different biochars (Miscanthus x giganteus straws, coffee husks and woody material) at two different concentrations (1 % and 3 %; w/w) to soil samples, we investigated the effects on the soil respiration, the chemical characteristics and the kinetic release of bio-available Si (CaCl2-extractable Si).


Here we show that the biochar from Miscanthus straws was the most attractive amendment. Its incorporation at a 3 % rate improved the soil fertility parameters (pH and available cations) and combined the highest mean residence time of carbon (C) in soil (MRT = 50 years) with the highest rate of release of bio-available Si. We attribute this result to the presence of phytoliths in this biochar, as revealed by SEM-EDS analysis.


Not only did the biochar from Miscanthus enhance both soil C sequestration and fertility, but the results of this study suggest that it can also be considered as a potential source of bio-available Si. Although our conclusions should be substantiated in the field, we suggest that Miscanthus biochar could be used as a potential source of bio-available silicon for the culture of such crop as Si-accumulator plants growing, for instance, in highly weathered tropical soils with low content in carbon, nutrients and bio-available Si.

Human Influences on Nitrogen Removal in Lakes

Jacques C. Finlay, Gaston E. Small, Robert W. Sterner (2013). “Human Influences on Nitrogen Removal in Lakes.” Science 342(6155), 247-250. DOI:10.1126/science.1242575

Abstract: Human activities have increased the availability of reactive nitrogen in many ecosystems, leading to negative impacts on human health, biodiversity, and water quality. Freshwater ecosystems, including lakes, streams, and wetlands, are a large global sink for reactive nitrogen, but factors that determine the efficacy of freshwater nitrogen removal rates are poorly known. Using a global lake data set, we show that the availability of phosphorus, a limiting nutrient, affects both annual nitrogen removal rate and efficiency. This result indicates that increased phosphorus inputs from human activities have stimulated nitrogen removal processes in many lakes. Recent management-driven reductions in phosphorus availability promote water column accumulation and export of nitrogen from large lakes, an unintended consequence of single-element management that argues for greater control of nitrogen as well as phosphorus sources.

See also:

Field, fuel & forest: Fellows Friday with Sanga Moses

Read the full interview on the TED Blog.

When former accountant Sanga Moses ran into his sister on a far-from-home road carrying firewood on what was supposed to be a school day, his life changed. He knew that Uganda’s rapidly disappearing forests had big implications for the environment, but he hadn’t recognized the day-to-day effect it was having on the lives of his family and village. Now, with his company Eco-fuel Africa, Moses helps farmers transform agricultural waste into cooking fuel, and also sponsors tree-planting projects. Here, he tells the TED Blog about fast-changing ecological conditions in Uganda, and how he hopes to help restore the country’s forests as quickly as possible.