Tree-Ring Talk

Climate Response of Four Tree Species from the East-German Low Rainfall Area

Climate response was investigated for four tree species in the East German low rainfall area in Thuringia where average annual precipitation falls below 600 mm. Black Pine (Pinus nigra) has large semi-natural stands on calcareous soils far north of its natural distribution, Common Ash (Fraxinus excelsior) reaches its physiological limit along calcareous slopes.

Sky Island Investigators: Where Students Become Scientists

We offer a diverse variety of science field classes – on the UA Campus at the Bryant Bannister Tree Ring Building, at Tumamoc Hill, and at field sites in the Catalina Mountains - where students learn that science is a dynamic process of gathering and evaluating information. We adapt our innovative approach to work with teachers and students of all ages and grade levels, depending on the needs of your students.

What We Did Last Summer

Dendroecology 2014 Course Presentations

Hear presentations on the Dendroecology 2014 pre-session course research topics.

Reconstructing Klamath River Flow with Uncertain Instrumental Records: a Mathematical Tale of Passion, Deception, and Desire

Higher temperatures negatively affect tree growth at multiple spatial scales in the western United States

Annual tree growth is tightly regulated by climate.  As air temperature increases, evaporative demand also increases, changing the dynamics of water availability in forest ecosystems.  By correlating tree growth with precipitation, temperature, climatic water deficit, and vapor pressure deficit, we show that higher temperatures decrease tree growth across all spatial scales and regions.  We use a novel dataset of Douglas-fir chronologies from 122 sites distributed throughout all mountain regions and a broad range of climate regimes in the western United States.  By sampling throughout “clim

A tree-ring based assessment of climate-growth relationships in the Miombo region in Tanzania

Drought events have significant impacts on domestic use, agriculture, and ecosystems. Water shortage is projected to increase with globally rising temperatures and the increasing demand for this resource. This will likely be one of the major limitations for future development in drought limited regions like Tanzania. Socio-economic development and natural resource productivity in Tanzania are mostly depending on water availability.

Climate Change and Invasive Species as Agents of Evolution and the Use of a New Research Platform, The Southwest Experimental Garden Array, to Provide Genetics-Based Solutions to Assisted Migration and Other Global Challenges

Climate change, invasive species and other global challenges are agents of selection that are affecting the ecology and evolution of foundation plant species (cottonwood, pine, eucalypts).  These impacts cascade to affect whole communities of associated species and their ecosystem processes.  Using observational studies in the wild and common garden experiments we partition genetic and environmental variation and show how gene by environmental interactions are redefining communities composed of 1000s of species.  Using an array of common gardens where the same genotypes, populations and mul

Augmenting the Interior West Forest Inventory and Analysis Program with a Dense Network of Tree Ring Data

The Forest Inventory and Analysis (FIA) program of the USDA Forest Service has conducted state-by-state forest inventories for 80 years.  Because of an emphasis on individual states as inventory units, for most of the program history it was rare for contiguous areas larger than one or two states to be measured concurrently.  As a result, attempts to conduct details time-series analysis tended to be limited by confounding geographic bias.  When the FIA program converted to a new annual inventory system, starting in the late 1990s, issues with geographic and temporal bias were mostly eliminat

Adaptation to environmental variation in short-lived organisms: what can tree rings tell us?

Organismal survival can depend on response to environmental variation.  Several modes of response to environmental variation have been documented, including adaptive tracking, adaptive phenotypic plasticity and the evolution of so-called “bet hedging” traits.  I present empirical evidence that short-lived organisms, including the monocarpic herb, Lobelia inflata (Campanulaceae), adapt to environmental variation.  Genetic population differentiation among traits of five eastern North American populations of L.

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