Agriculture
The Quality of Plants Is Declining Because of Climate Change
Here’s why it matters
Balance is, without question, important in plant biology: Too much or too little sun, the right amount of rainfall, the right temperature range, and the necessary soil nutrients are critical to maintaining a healthy and diverse plant community.
But that stability is being threatened by climate change; in part because of peripatetic changes in climate, but even more by what is happening with carbon dioxide, the primary global warming gas. For the recent geological past (a couple million years, perhaps longer), there hasn’t been enough carbon dioxide in the air to maximize photosynthesis, growth, and yield for about 90 percent of all plant species. But now, BOOM, carbon dioxide levels are soaring, having risen 30 percent in my lifetime, and likely to rise another 50 percent by the end of the century — so very, very fast.
There are literally hundreds of published studies showing that recent and projected changes in carbon dioxide stimulate photosynthesis, growth, and yield for hundreds of plant species. CO₂ is plant food.
So, this is a good thing, yes? More CO₂, more plant growth, more food.
When you change a resource needed by plants, not every plant species responds the same way. If you are an avid gardener, try this: Dump lots of fertilizer in your garden, and tell me what responds more, weeds or flowers?
Dump lots of fertilizer in your garden, and tell me what responds more, weeds or flowers?
Let’s apply the fertilizer example to CO₂. If I add more CO₂ to a field of rice, we have found that rice responds a little, but weeds in the field respond a lot, lowering the yield of rice. What if I add more CO₂ to a natural ecosystem? Well, again, some plants, often invasive weeds like kudzu, can respond much more to the new resource, to their benefit, but to the detriment of other plant species, and in time, to biodiversity. To assume that more CO₂ automatically translates to increases in plants that only humans desire reflects a desperate and dogmatic ignorance of how plants and plant communities…
