Petaluma Profile: A solution for climate change is right under our feet
On a brisk April morning, on a 3-acre property in west Petaluma — where ecologist Elizabeth (Libby) Porzig lives with her biologist partner, Scott Jennings — a chocolate lab named Abbie greeted me as I arrived at the ranch. As dark-faced sheep grazed in the verdant field just beyond the fence, a motley flock of chickens surrounded me.
“The chickens are hoping for treats,” Porzig laughed, as she emerged from a barn to greet me.
Porzig, 40, is an ecologist who leads a team of scientists at Point Blue Conservation Science, a Petaluma-based non-profit organization. She grew up in the suburbs of the South Bay, where her family’s backyard gate opened onto undeveloped woodland. There, she played and learned about living things in nature.
“I grew up with an awareness that there is no such thing as ‘nature’ and ‘not nature’ because nature is everywhere. It was in my backyard,” she remembered.
After college, Porzig interned at Point Blue, studying songbirds at their Palomarin field station and in the Eastern Sierra, where her interest in ecology and birds grew. She earned a doctorate in ecology at UC Davis and has worked at Point Blue since. She and her group study rangelands, a broad term that describes more than 40% of California's land — grasslands, oak savanna and coastal prairie.
Because much rangeland is privately-owned, Porzig’s team works with landowners such as ranchers and farmers to better understand rangeland ecosystems and to develop science-based conservation solutions.
“Ranchers and farmers are passionate about their role as land stewards, not just to promote healthier ecosystems and wildlife, but also to benefit their farms,” she said.
Many farmers have come to understand that what’s good for conservation, like healthy grassland, may also be good for their livestock animals.
“Many people may not immediately think of agriculture as ‘nature,’ but working rangelands hold amazing biodiversity, including species in decline such as American badgers and grasshopper sparrows,” she said. “They also serve as connectors that allow animals to travel in a landscape segmented by human activities such as development and roads.”
Over the years, Porzig’s working rangeland team has monitored soils, birds, and plant populations. They’ve recommended an array of land management solutions to landowners and policymakers to support biodiversity and ecological conservation.
“For example,” she said, “we’ve worked on solutions like restoring oak trees to rangelands, installing fences to control access of grazing animals to sensitive riparian habitats near creeks, and building fences so that wildlife can safely crawl under or go over them.”
Today, scientists like Porzig, along with farmers, climate change activists, and lawmakers, understand the critical role that soil — including rangeland soil — plays in sequestering carbon dioxide, the primary greenhouse gas produced by human activities. Carbon sequestering can mitigate, and perhaps even help reverse, the effects of climate change.
“Carbon dioxide in the air is captured by plant material, through photosynthesis,” Porzig said, describing the natural process. “It's then converted by microbes in the soil into organic matter, and the organic matter is what gives soil its chocolate cake-like texture.”
She showed me a small soil sample she’d dug up, to demonstrate how scientists collect samples. The 1-inch diameter piece of earth was dry, indicating little precipitation we’ve had in recent days.
“When there is a lot of organic matter in the soil, it means there is a lot of carbon in it,” she explained. “We can reduce the effects of climate change if we can capture and store enough of the carbon in the soil at scale.”
Porzig is clearly excited.
Last fall, California Governor Gavin Newsom issued an executive order popularly called “30 x 30,” which commits the state of California to protect 30% of land and coastal water by 2030. The order includes the conservation of working rangeland. In late January, President Biden's administration joined in to protect 30% of U.S. land and waters, “to tackle the climate crisis,” the White House briefing stated.
“Of course, addressing our energy and transportation sectors and many other things are important, but I think a nature-based solution has a lot of promise,” Porzig said.
She believes the data that her team collects and the scientific reports they produce will help guide governments to reach these ambitious conservation goals.
Like the woodland she played in when she was a child — which has since been developed to make room for more homes — rangelands are disappearing rapidly.
Still, Porzig is hopeful.
“Through human activities, we've lost a lot of the carbon that's been in the soil globally,” said Porzig. “I believe that human activities can be part of the solution by putting carbon back in the soil.”