The World’s Forests Are Growing Younger

Study finds climate change is altering forest structure, making forests less of a carbon sink

--By Christina Procopiou 

Researchers from Berkeley Lab and 20 other institutions have found that land use and atmospheric changes are altering forest structure around the world, resulting in fewer of the mature trees that are better at storing carbon dioxide from the atmosphere.

The scientists evaluated data and observations from more than 160 previous studies designed to capture how interactions between forest vegetation, climate changes, and disturbance such as drought provoke ecosystem responses including increased tree mortality and decreased forest age. Results of their work, led by researchers at the Pacific Northwest National Laboratory, were published recently in the journal Science.

“This change in forests from old to young is something to be concerned about,” said Lara Kueppers, Berkeley Lab faculty scientist, co-author of the paper, and co-investigator involved in the DOE’s Next-Generation Ecosystem Experiments - Tropics (NGEE-Tropics) project. “In younger forests, there are, on average, fewer large trees. The lack of large trees tends to drive down the carbon stored in biomass, whereas to address climate change we want forests to hold on to as much carbon as possible.”

Kueppers, who led a 2018 DOE workshop which prompted this review paper, contributed to the study by evaluating the ability of forests to regenerate and recruit new trees following natural disturbance, such as wildfire and drought, and chronic climate change. The researchers conclude that the observed trends provide a critical test for Earth System Models designed to simulate changing forest dynamics.

Read Pacific Northwest National Laboratory’s news release about this paper here.

New Research Evaluates How U.S. Wind Plant Performance Changes with Age

First comprehensive study of the U.S. wind fleet shows relatively low levels of performance decline with age

--By Kiran Julin

U.S. wind plants maintain 87% of peak performance after 17 years, and newer plants show almost no decline over the first 10 years, according to a recent study from Berkeley Lab. Compared to studies of how European wind fleets age, the U.S. wind fleet shows mild performance loss with age, and plants built after 2008 show the lowest levels of performance decline that have been found in a major fleet.

A team of researchers in Berkeley Lab’s Energy Analysis & Environmental Impacts Division analyzed the performance of 917 onshore wind projects in the U.S. Their findings were published recently in the journal Joule.

The U.S. wind market is the second-largest in the world and supplied 7.3% of the nation’s electricity generation in 2019, yet this is the first research effort to evaluate the impact of plant age on the performance of the U.S. wind fleet.

“The results indicate that age-related performance loss can be influenced by technology choices and cost-benefit decisions by project operators,” said Berkeley Lab scientist Dev Millstein, the corresponding author of the paper. “The study provides evidence that recent technology changes are positively influencing how wind plants age.”   

Read the full article here at Berkeley Lab’s Energy Analysis & Environmental Impacts Division website.

Investigation into Fungi Food Choices Yields a Buffet of Information

A study of how fungi sense and respond to available food helps explain nutrient recycling and opens the door to better methods for producing bio-based products

--By Aliyah Kovner

When you hear the word “fungi” there is a good chance that it conjures an image of an idyllic toadstool, or perhaps a cluster of capped mushrooms, growing out of a fallen log or pile of leaves. Though there are amazingly diverse types of fungi across the planet, fungi that decay plant matter like these iconic forest inhabitants are of particular interest to scientists because the enzymes that they use to break down tough plant cell walls into simple sugars can be mass-produced and used in industrial processes that generate valuable carbohydrate-based compounds, such as biofuels.

Interestingly, these fungi are capable of tailoring which plant cell wall-degrading enzymes they secrete based on the composition of the food sources available. To investigate how the fungi sense and respond in this manner, a team of scientists led by UC Berkeley used multiple techniques to study the genes, gene products, and gene regulation processes in the fungus Neurospora crassa. The recently published work – a collaboration of N. Louise Glass’ Lab with researchers from the U.S. Department of Energy Joint Genome Institute (JGI), located at Berkeley Lab, and the Technical University of Munich – adds to a rich array of studies seeking to improve our understanding of fungal genomes.

 "This paper explored how ascomycete fungi – the largest phylum within the fungal kingdom – choose what things to eat in an environment of many food choices,” explained first author Vincent Wu. “Curiosity aside, these fungi are currently being utilized to produce enzymes, proteins, and other chemicals in mass quantities, so understanding how they decide what to eat can lead to novel ways of engineering these organisms to more efficiently and sustainably assemble these products. Furthermore, this research included a massive transcriptomics analysis with the use of DAP-seq, a powerful new genetic analysis tool implemented at the JGI.”

Journal Link: Science Journal Link: Joule