|
Sun | Mon | Tue | Wed | Thu | Fri | Sat |
|---|
July | July | July | July | July | July | 1 |
2 | 3 All day August 3, 2020-August 6, 2020 ESA’s Annual Meeting will be entirely online this year (due to COVID-19).
| 4 All day August 4, 2020-August 6, 2020 ESA’s Annual Meeting will be entirely online this year (due to COVID-19).
| 5 All day August 5, 2020-August 6, 2020 ESA’s Annual Meeting will be entirely online this year (due to COVID-19).
| 6 All day August 6, 2020-August 6, 2020 ESA’s Annual Meeting will be entirely online this year (due to COVID-19).
| 7 | 8 |
9 | 10 | 11 10:00 am-11:30 am August 11, 2020 Students in Cohorts 1 (started Fall 2019) and 2 (starting Fall 2020) should plan to join us for information about the program and the kick-off for the 2020-21 academic year. Please contact Kimberly for a link to the Zoom meeting if you haven’t received it.
| 12 | 13 | 14 | 15 |
16 | 17 11:30 am-12:20 pm August 17, 2020 Title: Increasing wildfire severity stimulates carbon storage in Alaskan boreal forest Abstract: In the boreal forests of North America, climate warming is shifting the wildfire disturbance regime to more frequent, intense fires that burn more deeply into organic soils, releasing historically sequestered carbon (C) to the atmosphere. Fires drive both immediate and decadal changes in C dynamics, so the potential for fire to destabilize C storage must be considered in the context of long-term ecological change. Here we show that fire-induced shifts in dominant plant species of Alaskan boreal forests can compensate for fire-driven losses of surface soil C. Severe burning of organic soils shifted tree dominance from slow-growing spruce to fast-growing deciduous species, resulting in a net increase in C storage over the disturbance cycle. Lower flammability and fire severity in a future boreal forest dominated by deciduous trees could protect these C pools and increase their tenure on the landscape, resulting in a negative, mitigating feedback to climate warming.
| 18 | 19 | 20 | 21 | 22 |
23 | 24 11:30 am-12:20 pm August 24, 2020 Title: Shaking Hands between Eddy Fluxes and Remote Sensing
Lessons Learned: 1982-2020 Abstract: To achieve our big picture goal of assessing trace gas fluxes everywhere, all the time, there needs to be handshaking between ecosystem scale carbon and water flux measurements and remote sensing proxies of ecosystem structure and function. Remote sensing information provides an inexpensive way to upscale trace gas fluxes in space. But, it needs ground-truthing and gap filling in time. Continuous trace gas flux measurements provide this necessary information. In this talk we explore experiences using remote sensing information (gap fraction, reflected visible and near infrared radiation, digital cameras) derived from sensors on towers to assess the temporal dynamics and spatial variability of such variables as leaf area index, phenology, photosynthetic capacity, canopy height and ecosystem photosynthesis. We discuss new ideas and data on the use of reflected near infrared radiation from vegetation as a better proxy for photosynthesis. We also discuss the role and need of flux footprint models to produce more representative comparisons between fluxes and remote sensing indices.
| 25 | 26 | 27 | 28 | 29 |
30 | 31 11:30 am-12:20 pm August 31, 2020 Speaker: Dr. Kyle Doherty, MPG Ranch Postdoctoral Researcher, NAU School of Forestry AdjunctTitle: Coarse-filter bee conservation strategies benefit from fine-grained topography data
Abstract
Climate change complicates the task of prioritizing sites for conservation, because conditions that currently support biodiversity may not in the future. One strategy to circumvent this problem is to prioritize sites that are diverse in climate-resilient abiotic conditions, such as geology and topography. Geodiverse areas contain more niche space, are more likely to maintain processes that promote biodiversity in the future, and thus are useful coarse-filter surrogates for site prioritization. Comparatively few studies have scrutinized the relevance of topography to invertebrate pollinators, and the importance of data below 30 m grain-sizes is largely unknown, though could be useful for identifying microrefugia and corridor designation. We surveyed grass, shrub, and woodland sites for bees and plants in the Sapphire Mountains of western Montana, USA to explore if coarse-filter strategies are effective for these groups. We gathered fine-grained elevational data for the region with structure-from-motion photogrammetry, and derived metrics of topodiversity with these data to study the importance of grain-size (0.25 to 250 m) and neighborhood (1 to 500 m) of topodiversity calculation. We found that bee rarity-weighted richness (RWR) was most strongly correlated with 2 m grain topodiversity data, while plant RWR was most strongly correlated with 235 m data. We explored the potential for hierarchical models spanning grain-sizes and neighborhoods, but found that simple linear models of topodiversity performed best at ranking sites by RWR in both groups. The best model for plants performed relatively poorly for the task of bee site prioritization. Modeling RWR with pooled biodiversity data aggregated from both groups slightly improved site rankings for bees and slightly decreased ranking performance in plants. While the costs of fine-grained elevational remote sensing technologies may be high at present, national efforts to gather these data are on the horizon, and may facilitate conservation of bees and other groups at the local scale.
Speaker: Dr. Adrianna Foster, NAU SICCS Postdoctoral Researcher
Title: Simulation of boreal treeline migration in a warming world
Abstract The North American boreal region is warming at an accelerated rate compared to the rest of the globe, which will impact vegetation, soils, and the disturbance regime. Recent studies using modeling, remote sensing, and field data predict boreal range shifts, with contractions predicted in the southern margins as a result of drought and insect infestation, and expansions predicted in the northern margins as temperatures warm. While the climate suitability ‘envelope’ for boreal tree species may be expanding northward with climate change, it is still unclear how fast migration may actually occur given constraints on seed rain, regeneration, and growth to reproductive age and size. We use an individual-based forest model (UVAFME) to simulate forest response to changing climate at the northern treeline in interior Alaska and to assess the potential for a northward treeline shift. UVAFME has been previously used in interior Alaska and comparisons with inventory data and other abiotic characteristics show good agreement with observations. UVAFME is updated for this study to simulate seed rain from a source grid cell to adjacent grid cells, dependent on the density of and distance to reproductively active trees. Model results predict a northward shift in the treeline, though the speed of this shift is sensitive to local-scale conditions as well as the parameters used for seed dispersal. These results have implications for changing biogeophysiology at the broader tundra-taiga ecotone, as increasing forest cover would alter energy and water fluxes, soil conditions, as well as the fire regime.
| September | September | September | September | September |
