NY Times: "by 2100 half of all the world’s plant and animal species may disappear"

The Hidden World of Soil Under Our Feet - NYTimes.com

THE world’s worrisome decline in biodiversity is well known. Some experts say we are well on our way toward the sixth great extinction and that by 2100 half of all the world’s plant and animal species may disappear.
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Global warming will no doubt greatly compound the threats to soil biodiversity. Food security is a big concern. What will happen to crops as the earth gets warmer? Slight changes in temperatures and moisture can have profound impacts on soil, altering the composition of soil life and the types of plants that will grow. We may no longer be able, for example, to grow wheat in Kansas.