Biochar is a fine-grained, highly-porous charcoal produced from carbon-rich biomass feedstocks, including forestry waste, animal manures and agricultural waste products such as husks, shells and stover.(Stover is the dry stalks of crops such as corn, sorghum or soybean that remain in a field after harvest.) Biochar is produced by pyrolysis or gasification (heating the biomass with little or no air) in a process similar to the production of charcoal. However, the primary use of biochar is as a soil improver rather than a fuel. Biochar has been shown to add value to soils in terms of fertility, particularly to acidic soils. The exact details of the mechanism of action are not fully established, but it may act by filtering out and retaining nutrients from percolating water in the soil or by changing crumb structure. Biochar shows a mean residence time in the soil in the range of hundreds to thousands of years, making it a long-term carbon store (compared with uncharred biomass) and hence a long-term contributor to climate change mitigation. Also, some of the wastes proposed as feedstock for making biochar are currently burned or composted which returns all or part of their carbon to the atmosphere quickly and, in the case of anaerobic composting or landfilling, produces methane which is a more potent “greenhouse gas” than carbon dioxide.
There is a range of possible investigative work that can be done with biochar (or other substances that could affect soils and soil fertility). Some (as described in the IBI Biochar Trial Guide on the IBI website) is beyond the scope of schools. However, a medium-term student project at Advanced level could explore some biochar issues, and even at Introductory level, students could investigate the effect of adding biochar or charcoal to the growing medium used to grow seeds in pots.
Download the publication from McAfee.
Until now, spam’s impact has been measured in time, money, and aggravation. It turns out there is a massive environmental impact as well. McAfee recently commissioned climate-change consultant ICF International and spam expert Richi Jennings to calculate the environmental impact of spam. The results that came back were startling: The energy consumed in transmitting and deleting spam is equivalent to the electricity used in 2.4 million U.S. homes, with greenhouse gas (GHG) emissions equivalent to 3.1 million passenger cars.
By taking an environmental approach to email spam, McAfee hopes to aid decision makers working to stem the tide of spam and open a timely conversation about how it affects the planet.
This report from Telework Exchange collects data from nearly 40,000 participants in Telework Week 2011, and finds that employees can save billions in commute costs while boosting productivity by working at home two days per week.
From the report:
- Telework Week Snapshot: 39,694 employees teleworked during Telework Week – 10% of participants had never teleworked before; 22% previously teleworked on an ad-hoc basis; and 86% work for the Federal government
- More Productive: Organizations and employees reported increased employee productivity during Telework Week
- More Time & Money: Telework Week participants realized significant savings – gaining approximately 2 hours back into their lives each day spent teleworking, and saving approximately $2,730,229 total. Teleworking 2 days a week is an equivalent to $3,439 annual raise
- More Involved: Managers have turned the corner on telework; 60% of organizations say their management is more open to and encouraging of telework vs. one year ago
- More Telework: If all eligible Feds teleworked 2 days a week for a year, they would avoid driving 5.5 billion miles and save $3.8 billion in commuting costs
Read the full story at Earth911.
Biofuels are touted as an energy source that can cut greenhouse gas emissions and reduce our dependence on foreign oil. But could replacing fossil fuels with biofuels raise world food prices and cause hunger and poverty in developing countries?