While unpleasant car exhaust makes us wrinkle our noses, such human-made fumes may pose serious problems to insects searching for nectar. Researchers recently revealed that background odors make finding flowers difficult for pollinators. The study, published in Science, measured how hawk moths (Manduca sexta) pick out the sacred datura flower scent (Datura wrightii) amidst all the other smells that waft through the environment. Datura’s brilliant 15-centimeter trumpets leap from dark, heart-shaped leaves, sending smelly signals into the arid sky of the southwestern deserts where they grow.
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Las turbinas eólicas, ¿afectan el valor de las propiedades?
Los desarrollos de aerogeneradores no tienen efecto en el valor de las propiedades como casas y granjas cercanas, según una nueva investigación de la Universidad de Guelph.
Publicado en una edición reciente de la revista Canadian Journal of Agricultural Economics, el estudio se cree ser el primero, revisado por científicos, sobre esta cuestión en Canadá.
What to do with all that zoo poop
Ron Patalano, director of operations at Roger Williams Park Zoo, has high praise for his staff. After all, it takes a mighty amount of shoveling to fill the two 30-yard Dumpsters of animal excrement that are hauled away weekly as part of the zoo’s recycling program.
Added to the grass clippings, vegetable scraps, animal bedding, hay and other natural materials trucked to Earth Care Farm in Charleston for composting, are 624 tons of manure produced annually by the zoo’s 280 inhabitants.
Keeping yards and buildings waste free “is not an easy job,” Patalano noted.
The zoo’s relationship with Earth Care Farm — Rhode Island’s longtime composting mecca — goes back at least 15 years, according to John Barth, the farm’s manager.
Nitrous Oxide emissions and Ice Ages
Nitrous oxide (N2O) is an important greenhouse gas that doesn’t receive as much notoriety as carbon dioxide or methane, but a new study confirms that atmospheric levels of N2O rose significantly as the Earth came out of the last ice age and addresses the cause.
An international team of scientists analyzed air extracted from bubbles enclosed in ancient polar ice from Taylor Glacier in Antarctica, allowing for the reconstruction of the past atmospheric composition. The analysis documented a 30 percent increase in atmospheric nitrous oxide concentrations from 16,000 years ago to 10,000 years ago. This rise in N2O was caused by changes in environmental conditions in the ocean and on land, scientists say, and contributed to the warming at the end of the ice age and the melting of large ice sheets that then existed.
Usar más gas natural ¿minimizará o exacerbará el clima?
Las plantas de energía de gas natural producen importantes cantidades de gases que provocan el calentamiento global. La sustitución de viejas plantas eléctricas a base de carbón con nuevas plantas de gas natural podría causar que el daño climático aumente en las próximas décadas, a menos que sus tasas de fugas de metano son muy bajas y las nuevas plantas de energía sean muy eficientes...
Scientists estimate the total weight of plastic floating in the world's oceans
Nearly 269,000 tons of plastic pollution may be floating in the world's oceans, according to a study published December 10, 2014 in the open-access journal PLOS ONE by Marcus Eriksen from Five Gyres Institute and colleagues. Microplastic pollution is found in varying concentrations throughout the oceans, but estimates of the global abundance and weight of floating plastics, both micro and macroplastic, lack sufficient data to support them. To better estimate the total number of plastic particles and their weight floating in the world's oceans, scientists from six countries contributed data from 24 expeditions collected over a six-year period from 2007-2013 across all five sub-tropical gyres, coastal Australia, Bay of Bengal, and the Mediterranean Sea.