Food webs on host plant inflorescences
Phenological Drivers of Herbivore Abundance
We have monitored arthropod abundance in ten Ligusticum populations for the last seven years. From these data, we can see that yearly variation in the abundance of aphids (Aphis asclepiadis) is not a function of any of the usual suspects: host plant phenology or abundance, temperature or precipitation. Instead, years of greater aphid abundance are associated with later snowmelt dates. When the snow melts earlier or later from a site, many factors could change that would effect aphid abundance. One possible driver of the snowmelt-aphid relationship are predators known as lygus bugs. These hemipterans achieve their peak abundances in years with earlier snowmelt dates. When snowmelt comes later, soils around the host plant will stay moist. This moisture likely effects plant physiology and perhaps phloem sap quality for aphids. Our NSF-funded grant allows us to experimentally test for these mechanisms. Projects in 2018 explored (1) the relationship between soil moisture and aphid abundance and (2) decomposed the effects of lygus herbivory on plant volatiles and host plant seed set.
We have monitored arthropod abundance in ten Ligusticum populations for the last seven years. From these data, we can see that yearly variation in the abundance of aphids (Aphis asclepiadis) is not a function of any of the usual suspects: host plant phenology or abundance, temperature or precipitation. Instead, years of greater aphid abundance are associated with later snowmelt dates. When the snow melts earlier or later from a site, many factors could change that would effect aphid abundance. One possible driver of the snowmelt-aphid relationship are predators known as lygus bugs. These hemipterans achieve their peak abundances in years with earlier snowmelt dates. When snowmelt comes later, soils around the host plant will stay moist. This moisture likely effects plant physiology and perhaps phloem sap quality for aphids. Our NSF-funded grant allows us to experimentally test for these mechanisms. Projects in 2018 explored (1) the relationship between soil moisture and aphid abundance and (2) decomposed the effects of lygus herbivory on plant volatiles and host plant seed set.
Confluence of Fountain Creek and Arkansas River (Photo by Jeffrey Beall)
This PFCs in Fountain Creek Riparian Food Webs
We are examining the movement of PFCs through riparian food webs. This work was funded by 2018 LAS Dean’s Research Initiative: Environmental PFC Impact Collaboration (EPIC) in the Fountain Creek Watershed: Determining the Environmental, Ecological, and Societal Impact of PFCs. Projects are assessing the extent to which these compounds move through trophic levels (plants-herbivores-carnivores) in the field and laboratory. We are using a combination of observational and experimental approaches. This will include sampling riparian food webs in the field, and rearing model food webs in laboratory growth chambers.
We are examining the movement of PFCs through riparian food webs. This work was funded by 2018 LAS Dean’s Research Initiative: Environmental PFC Impact Collaboration (EPIC) in the Fountain Creek Watershed: Determining the Environmental, Ecological, and Societal Impact of PFCs. Projects are assessing the extent to which these compounds move through trophic levels (plants-herbivores-carnivores) in the field and laboratory. We are using a combination of observational and experimental approaches. This will include sampling riparian food webs in the field, and rearing model food webs in laboratory growth chambers.
Freshly harvested Ligusticum roots
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Ecological Determinants of Medicinal Activity
Humans depend on medicinal plants. Many people still rely on traditional herbal medicine and pharmaceutical drug discovery also uses the compounds found in nature. Plant defense theory predicts that plants in the shade will be better defended than plants in higher light environments. Since plant defense compounds are frequently responsible for medicinal activity, this suggests that plants in the shade will be a richer source for the bioactive compounds used in herbal medicine and drug discovery. Our previous work has shown that extracts of Ligusticum from the shaded aspen understory have greater antibacterial activity than extracts from plants in open meadows. We collaborate with analytical chemists from the UCCS Department of Chemistry to apply a quantitative HPLC method to assess this variation. Our research found distinct chemotypes between roots collected on the Front Range versus the Western Slope of Colorado. Read about it here. |
Course-Based Undergraduate Research
Real-world research experiences are fully incorporated into two courses at UCCS: BIOL 4460 Methods in Field Ecology and BIOL 3750 Conservation Biology. These include long-term monitoring efforts where classes contribute data to larger projects. Students have the opportunity to present their research at regional conferences such as the Front Range Student Ecology Symposium and the Colorado Undergraduate Research Forum.
Real-world research experiences are fully incorporated into two courses at UCCS: BIOL 4460 Methods in Field Ecology and BIOL 3750 Conservation Biology. These include long-term monitoring efforts where classes contribute data to larger projects. Students have the opportunity to present their research at regional conferences such as the Front Range Student Ecology Symposium and the Colorado Undergraduate Research Forum.