Kirsten de Beurs | USGS Science

USGS2025

Phenology in higher education

Phenological data collection and analysis are well-suited to higher education settings, providing valuable opportunities for hands-on data collection, manipulation, and interpretation. Few subjects are more conducive or accessible for engaging diverse learners in meaningful and impactful science at such large scales and minimal cost. In this chapter, we provide a range of examples of how instructors have incorporated observing and analysis of seasonal phenomena into their curricula. Many of these examples can be readily replicated and folded into new courses.

Book chapter↗

USGS2015

Phenological response of an Arizona dryland forest to short-term climatic extremes

Baseline information about dryland forest phenology is necessary to accurately anticipate future ecosystem shifts. The overarching goal of our study was to investigate the variability of vegetation phenology across a dryland forest landscape in response to climate alterations. We analyzed the influence of site characteristics and climatic conditions on the phenological patterns of an Arizona, USA, ponderosa pine ( Pinus ponderosa ) forest during a five-year period (2005 to 2009) that encompassed extreme wet and dry precipitation regimes. We assembled 80 synthetic Landsat images by applying the spatial and temporal adaptive reflectance fusion method (STARFM) to 500 m MODIS and 30 m Landsat-5 Thematic Mapper (TM) data. We tested relationships between site characteristics and the timing of peak Normalized Difference Vegetation Index (NDVI) to assess the effect of climatic stress on the green-up of individual pixels during or after the summer monsoon. Our results show that drought-induced stress led to a fragmented phenological response that was highly dependent on microsite parameters, as both the spatial autocorrelation of peak timing and the number of significant site variables increased during the drought year. Pixels at lower elevations and with higher proportions of herbaceous vegetation were more likely to exhibit dynamic responses to changes in precipitation conditions. Our study demonstrates the complexity of responses within dryland forest ecosystems and highlights the need for standardized monitoring of phenology trends in these areas. The spatial and temporal variability of phenological signals may provide a quantitative solution to the problem of how to evaluate dryland land surface trends across time.

Arizona↗