Opinion

FRAN ALEXANDER: Nature's infrastructure

Climate changes stressing local trees, plants, life

"Ecology isn't rocket science; it's much more difficult."

-- Steve Carpenter, professor of zoology

University of Wisconsin-Madison

Nature's infrastructure has been taking some major hits lately, giving us a glimpse of how various natural systems parallel, impact and intersect with human infrastructures.

Wildfires in 2020 set a record for the United States, destroying close to 9 million acres of forests, almost double what burned in 2019. With the loss of forests, also gone are their natural functions -- holding moisture in the ground, filtering air and water of pollutants, capturing carbon and cooling the atmosphere.

Hurricanes chewed up coastlines and communities in 2020 and set a record for the Atlantic season with 30 named storms, 14 of which became hurricanes. Surging waves remolded beaches, barrier islands, dunes and inlets. Ripping out vegetation, swamping marshes and estuaries and overwhelming natural coastal protectors like mangroves, the increased strength and frequency of the storms mangled nature's landforms and ecosystems.

Continuing its rise in setting yet another record, carbon dioxide in the atmosphere reached over 417 parts per million in May 2020, according to the National Oceanic and Atmospheric Administration. It seems like only yesterday (May 9, 2013) when carbon concentrations first broke 400 ppm and we humans said we'd do better. We didn't. Last Saturday, carbon dioxide reached 419.58 ppm. These are the highest carbon dioxide levels in human history and probably the highest in 3 million years.

As we're slowly grasping, carbon affects nature's infrastructure, which affects climate. Climate sets the stage for fires, storms, melting glaciers, rising sea levels, droughts, locust plagues and even freaky freezing temperatures. Some of these events seem to strike suddenly, but we're surprised only because we have not been paying attention to the warning signs.

The subzero temperatures to hit Northwest Arkansas in mid-February were bad enough, but by April, pollen was flying and ferns were unfurling; two-inch leaves had peeled out of bud covers; redbud trees were in glorious bloom; bees were buzzing and birds were in good cheer, declaring spring had arrived. Then WHAM! Again.

Spring shriveled and the new growth on trees, shrubs and flowers looked like a blowtorch had charred everything beyond recognition and seemingly beyond survival. As the weeks have passed, most plants have kicked in with Plan B, and in town the larger trees seem to have leafed out again. However, an aerial view of the forest cover across these hills would probably show differing degrees of green regeneration.

For instance, the eastern slope I live on between hills is likely a micro-climate area, and the oaks and hickories are not rushing their new growth. Because he's actually up in trees daily, I asked Jeremy Williams, a certified master arborist with Tree Climbers, if the oak's pollen-producing catkins are regenerating so there'll be acorns for deer and squirrels this fall. He said he's not seeing a strong return, and feels about 20% of the area's trees may have been harmfully stressed. This includes the nut-producing hickories, another bad sign for squirrels.

Tree survival is only part of the infrastructure's integrity. Many insects need tree leaves to host their eggs, and birds need caterpillars for baby food as well as bugs and seeds for themselves. Joe Neal, co-author of "Arkansas Birds," answered my concerns about the freeze saying that birds that migrate probably bypass damaged areas, but the freezing weather killed numerous robins, bluebirds and other lesser-known species that live here. He also shared concern about impacts on shrubs and flowering plants many critters depend on.

The opposite of infrastructure is chaos and the out-of-sync weather has disrupted insects' life cycles. Don Steinkraus, professor of entomology, said monarchs, for example, need both nectar for energy and milkweed for their eggs, both of which were destroyed in the late hard freeze. It was the same story for zebra swallowtail butterflies that lay eggs only on pawpaws. Lesser-known moths and butterflies attach eggs onto the leaves of oaks, hickories, hackberries, etc., and those probably perished as well.

Maybe, if this summer's heat holds off a while, tender new leaves won't be scorched and stressed even more while trying to recover tree energy, but if there's a drought, every living thing around here, including us, is going to be in even deeper trouble. Our continual environmental impacts continue to annually break records and scramble what were once functioning natural infrastructure systems. There are tipping points of no return environmentally, and we're pushing our luck.

Upcoming Events