GLOBE Plant Phenology

Phenology Phenology is the study of living organisms’ response to seasonal and climatic changes in their environment. Seasonal changes include variations in day length or duration of sunlight, precipitation, and temperature.

Plant growing season generally corresponds to the period between green-up and green- down. Growing season directly related to global carbon fixation and the amount of CO 2 in the atmosphere. Timing of green-up and green-down is important for understanding the global water cycle. As plants photosynthesize, they also transpire water from the soil into the atmosphere Plant Phenology

Green-up and green-down data are used to examine: –regional and global vegetation patterns –year-to-year trends –vegetation responses to climate change –wild fire danger –animal migrations Phenology

Uses of Phenology Measurements –Estimates of greenness values from remote sensing data vary because of problems from atmospheric properties, sun angle, aging of satellite detectors. –GLOBE ground-based observations will help scientists validate estimates of growing seasons. Phenology

Myneni,R.B. et.al Nature, 386, Increase in plant growing season length according to remotely sensed data There’s a need for ground observations/data.

Budburst Green-up Green-down Plant Phenology Protocols

Observe trees, twice weekly, starting at least two weeks before initial budburst. Report date of budburst when you see leaves breaking out of the buds in three different branches of each tree. Phenology: Budburst

Observe buds and report dates of green-up stages and leaf growth, twice weekly, starting at least two weeks before initial budburst. Measure leaf blade length until length stops increasing. Observe leaves twice weekly, starting two weeks before initial green-down Report dates of green-down color changes until leaf color change is complete or leaves fall off. Phenology: Green-up and Green-down

Plant Phenology: Green-down

A First Look at Phenology Sneak Preview of Budburst A Beginning Look at Photosynthesis Investigating Leaf Pigments 2 inquiry Learning Activities on our website Plant Phenology Learning Activities

77 schools in 11 countries 18 states in the US AK (34) and NY (6 schools) Plant Phenology Data Reporting

–Select deciduous native trees, shrubs or grasses. –Choose dominant over-story species –Avoid sites near buildings or where watering or fertilization is done –If possible, choose a location close to the Atmosphere and Soil Moisture Study Sites – Keep the elevation difference less than 100 meters Phenology Green-up & Green-down Site Selection

Supports understanding of big concepts in science such as systems and cycles Protocols and L.A. are aligned with science and math education standards Easy to fit in school day schedule because of short time required for measurements/observations Inexpensive equipment, i.e. ruler, color chart ; majority of students are already equipped with remote sensing equipment of eyes and touch Offers many opportunities for student science investigations and cross-curricular integration Why do Plant Phenology in schools?

Research Question: Can we observe differences in plant phenology (for same species) along an urban to rural gradient? Phenology Field Campaign

Green-Up and Green-Down Site Selection –Select deciduous trees, shrubs or grasses. –Choose dominant over-story species - Green-up and green-down data from satellites are affected predominantly by these dominant species –If over-story plants are evergreen conifers, use under-story broadleaf trees or shrubs –Try to use the same plants for green-up and green-down Phenology

Green-Up and Green-Down Site Selection –If possible, choose a location close to the Atmosphere and Soil Moisture Study Sites –Local topography can cause weather to vary even within short distances –Keep the horizontal distance between Phenology and Atmosphere and Soil Moisture Study Sites less than 2 kilometers –Keep the elevation difference less than 100 meters Phenology

Some Deciduous species in Alaska Quaking aspen Paper birch Black cottonwood Populus tremuloides Betula papyrifera Populus trichocarpa