Currently, humans are emitting around 29 billion tonnes of carbon dioxide<span> into the atmosphere per year. Around 43% remains in the atmosphere - this is called the 'airborne fraction'. The rest is absorbed by vegetation and the oceans. While there are questions over how much the airborne fraction is increasing, it is clear that the total amount of CO2 in the atmosphere is increasing dramatically. Current CO2 levels are the highest in 15 million years.</span>
Birth control pills contain a combination of hormones that prevent the formation of the ovule, by prevent the formation of the luteinizing follicle. There are several types of birth control pills,but the process is generally the same
Leaching is the process where dissolved nutrients in the
soil profile moves downward with percolating water. It is the loss of
water-soluble plant nutrients from the soil. The nutrients that seep through
the rooting zone may be recycled if roots grow deeper.
