麻豆淫院

Microclimates鈥攁s opposed to large-scale regional or even global scale macroclimate models鈥攎ay hold the key to offsetting the negative impacts of extreme weather events on already vulnerable insect populations.

This is the conclusion of a review paper published in , titled "Effects of microclimate variation on insect persistence under global change" and written by an interdisciplinary team of scientists from South Africa, Canada, Taiwan, Switzerland, and the United Kingdom.

Microclimates, also called microrefugia, can be many things, depending on the type of insect or habitat under consideration. In one instance, it could be a shaded area and varied topography in a built-up landscape that buffers temperature extremes and increases the availability of moisture. In another instance, it could be the entire canopy of the Amazon rain forest.

But without a better understanding of how insect species, many with complex life cycles, make use of microclimates to survive or adapt to a changing climate, our best climate models may still get it very wrong.

For Prof. John Terblanche, an evolutionary physiologist at Stellenbosch University's Department of Conservation Ecology and Entomology and a co-author on the paper, current macroclimate models are not viable for predicting impacts on insect populations.

"On the ground, observations are key to generating testable predictions," he argues. For example, if we observe that between two and three in the afternoon there are no bees at a specific feeder station or out and about foraging, this information can be used to validate the larger climate models. "We can form testable models that do not require hundreds of hours of observation," he explains.

These fine scale models often outperform the larger macroscale models. Typically, the larger models do not capture significant variations in climate conditions that directly influence insect behavior and developmental opportunities as the finer scale data are typically averaged out or not even sampled at all (e.g., under a leaf in a canopy where the insect lives).

"We have to be more strategic in capturing high resolution data at far finer scales in order to develop stronger predictive models," he says.

Such predictive models could, for example, also be used in agriculture to inform pest control strategies in insect pests such as fruit flies.

Dr. Wendy Foden, research manager at SANParks and extraordinary professor in SU's School for Climate Studies, says they are already implementing the idea of microclimates for vulnerable animal species.

In the Tankwa Karoo, for example, summer temperatures regularly exceed 40 to 50 degrees Celsius. SANParks partnered with the World Wildlife Fund and the University of Cape Town's FitzPatrick Institute of African Ornithology to mitigate the impact of extreme heat on birds by providing artificial shade at waterholes鈥攖hese are wooden frames with heavy shade cloth tacked over them鈥攚ith great success.

Similar strategies for creating microclimates have been implemented in South Africa for penguins and southern yellow-billed hornbills in the Kalahari Desert, and for other wildlife globally.

While it remains difficult to predict how insects are going to respond to a changing climate, the best way forward is for us to create connected and complex landscapes, with ample opportunities in all nooks and crannies for insects to take thermal refuge, hide and survive.

"By managing microclimates, we could balance the equilibrium between extinction versus colonization enough to delay anticipated rises in global extinctions from climate change," they write in the conclusion to the paper.

The key word here, however, is "delay": "Business as usual emissions pathways could imperil a third of Earth's species, so deploying management strategies rapidly, but with appropriate precautions, must become a priority. The future of the world's most diverse class of species, and potentially the indispensable services and functions they provide, depend on it," they conclude.