Tree-Ring Talk

Stronger together: Asynchronous tree growth dampens the impacts of accelerated climate change in a temperate rainforest

In this talk, I will introduce the idea that ecosystems located near glaciers can serve as natural laboratories for global change biology and paleoclimate studies. This is because they have experienced climate changes that were amplified by nearby ice-margin fluctuations. I will report on results from one of these natural experiments in the old-growth temperate rainforest near La Perouse Glacier in Southeast Alaska. We used dendrochronology to observe how tree growth responded to a shift from “normal” to accentuated rates of summer temperature change that occurred in the mid 1800s.

Hacienda de Gila: dendroarchaeology, architecture, and history at the Lyons and Campbell Ranch, Gila, New Mexico.

Buildings have stories. The materials, architecture, design, decoration and other attributes reveal life histories of a structure and often show changes through time. Sometimes, however, the stories are hidden and must be coaxed out of the building. Such is the case of the original Lyons and Campbell Ranch headquarters in Gila, New Mexico. Known in the 1890s as headquarters of the largest cattle ranch west of the Mississippi, the Lyons and Campbell Ranch actually has a much longer and more intriguing story.

Applications of acanthochronlogy on the Altiplano cactus Echinopsis atacamensis...or how I learned to love the bomb (pulse).

Cactus on the Altiplano of South America contain an archive of useful climate, physiological and demographic information in the isotopes of their spines. As demonstrated on saguaro cactus in Tucson, Arizona, spines emerge from the apex of the cactus, cease growth, and then are retained in time-ordered sequence on the side of the cactus as the stem continues to grow upward. Thus, time ordered sequences of spines contain diurnal, seasonal, and annual information in the oxygen and carbon isotope ratios of the robust spine tissue.

Field Guide to a Hybrid Landscape: Nebraska’s hand-planted forest

Dana Fritz will speak about her new book and exhibition, Field Guide to a Hybrid Landscape. This fascinating and little-known story of the first federal tree nursery and what was once the world’s largest hand-planted forest reaches beyond Nebraska with relevance to our current challenges of climate chaos and biodiversity collapse.


Forests and global change: from tree ecophysiological mechanisms to ecosystem processes

Forest ecosystems are particularly threatened by global change components, such as increasing frequency and severity of climate extreme events, increasing atmospheric carbon dioxide (CO₂) and pollutants concentrations. All these factors strongly influence the capacity of forests to continue providing important ecosystem services we rely on, including climate regulation and mitigation.

The University of Arizona Campus Arboretum: weaving science into landscape

The University of Arizona Campus Arboretum is comprised of woody plants located on the nearly 400 acre main campus in the heart of Tucson, AZ. Many of those woody plants are the product of Land-Grant research addressing state needs: initially addressing the 19th century need for an agricultural base to the Arizona Territory and later, responding to the 20th century need for resource-conscious landscapes as a result of increased urbanization and environmental concern.

Human securities, sustainability, and migration in the ancient U.S. Southwest and Mexican Northwest

In the US Southwest and Mexican Northwest, tens of thousands of people were on the move in the 1200s through 1400s CE. By the end of the 1400s, regional-scale population levels had declined by about 50%. What conditions led to this pulse of migration and depopulation? Here we show, through a Southwest/Northwest scale meta-analysis of sub-regional archaeological studies, the spatial distribution, intensity, and variation in social and environmental conditions within eight culture areas, prior to depopulation.

Influence of Viscum album on the growth of Pinus sylvestris in Poland and Central Europe

The growing intensity of climate change combined with increased urbanization is causing a modification of weather patterns in Central Europe, specifically the rising temperature and precipitation distribution and intensity in recent decades. These phenomena adversely affect groundwater levels, indirectly affect forest ecosystems, and contribute to declining in tree health. For example, this affects their susceptibility to external pathogens (i.e. insects, fungi, parasites, etc.) that can lead to tree mortality.

Stable isotopes in tree rings of Pinus heldreichii can indicate climate variability over the eastern Mediterranean region

A long-term context is important for understanding past climatic variability. Although tree-ring widths (TRWs) are widely used as a proxy for reconstructing past climate, the use of annually-resolved values of δ ¹³C and δ ¹⁸O tree-ring stable isotopes (TRSIs) is increasing and may provide further valuable information. Here, we present a 487-year-long TRW chronology and 240-year-long TRSI chronology for Bosnian pine (Pinus heldreichii H. Christ) and compare them to each other.

Widths and stable isotopes of Larix tree rings in a glacier-fed river basin in the Swiss Alps respond to a changing climate

Tree-rings are a valuable proxy for reconstructing past environmental conditions such as climate at annual or intra-annual resolutions. Tree-ring dating combined with stable isotope analysis (e.g. δ ¹⁸O and δ ²H) has an enormous potential for better understanding climate dynamics and for tracing freshwater resource availability under a changing climate.

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