250 likes | 264 Views
This preliminary report provides an overview of the research goals, field methodology, and preliminary results of a landscape phenology study conducted near the WLEF Tower. The study aims to understand plant phenology at a landscape level and the factors that drive phenological variations across the landscape. The report also outlines the works to be done, including exploring soil temperature impact, ground cover phenology analysis, genetic factor analysis, and more accurate land cover characterization. The study has implications for understanding fluxes and global change.
E N D
Spring Landscape Phenology near WLEF TowerPreliminary Report from 2007 Field Campaign(For ChEAS Meeting 2007, May 14th) Liang Liang, Mark D. Schwartz UW-Milwaukee
Content • Research Goals • Field Methodology • Preliminary Results • Works To Be Done
Research Goals • Understand plant phenology at landscape level • Understand the factors that drive phenological variations across the landscape • Connect to broader applications (Fluxes, Global Change)
Field Methodology • Intensive in-situ phenology sampling • Comprehensive microenvironment study
Intensive in-situ phenology sampling 5/03/2007 QuickBird 3/7 Cyclic Sampling, 72 plots, 216 trees Bi-daily observation 2006 April 29th –May 27th 2007 April 27th –May ?
Ground Cover Sampling 21 square plots (1m×1m)
Ground Cover Estimation 30% Ground Cover Greening D09 5/11/2007 10% Ground Cover Greening D09 5/1/2007)
Microenvironment Study • Over Winter Air Temperatures/Humidities (7 HOBOs from 9/17/2006-4/3/2007, 30min interval) • Spring Air Temperatures/Humidities (28 HOBOs deployed on 4/4/2007, 10min interval) • Soil temperatures measured with bi-daily, concurrent with phenology observation. • Soil Type, Elevation etc.
Microclimate Sampling 28 HOBOs
Specific Spatial Patterns of Phenology (Aspen, 2006 April 29th)
Specific Spatial Patterns of Phenology (Aspen, 2007 April 29th)
Specific Spatial Patterns of Phenology (Aspen, 2006 May 13th)
Specific Spatial Patterns of Phenology (Aspen, 2007 May 13th)
2006 Phenology Spatial Analysis Results • Tree Phenology is not spatially autocorrelated • Spatial variations in phenology are not clearly accounted for by differences in air temperature, air humidity, elevation, or soil type
2006 Phenology Temporal Analysis Conclusions • At the scale of this study, the initial relative timing of phenology is mainly determined by non-environmental factors • Once growth is initiated, phenological advancement is closely related to air temperature • Variations in the phenological stages among individual trees decrease as the spring season progresses
Climatic Impact on Phenologybased on 2006 data The advance rate of phenology is highly sensitive to previous 1 and 2 days degree hours accumulation.
Works To Be Done • Continue 2007 field campaign • Explore soil temperature impact on phenology • Ground Cover Phenology Analysis • Genetic factor analysis • Verify/refine conclusions of 2006 phenology spatial/temporal analysis • More accurate landcover characterization • Digital landscape phenology for calibrating satellite derived phenological indices • Sampling Area Expansion