Tag: Fuel Fire Grass and Compost

Effects of Rangeland Compost Amendments on Nematode Abundance

Presenter: Maya Treder – General Science

Faculty Mentor(s): Ashley Shaw, Lauren Hallett

Session: (In-Person) Oral Panel—Fuel, Fire, Grass and Compost, Poster Presentation

California rangelands are often over-grazed, nutrient-depleted, and subject to variable rainfall. Compost amendments are gaining popularity as a management tool due to their potential for soil carbon sequestration. Despite positive effects on plant growth, little is known about how soil communities respond to these amendments, especially across variable precipitation conditions. Nematodes are excellent indicators of soil community responses as they span every trophic level and are sensitive to changing environments. Here, we examined how amendment treatments (compost, fertilizer, none) affect nematode communities across variable precipitation conditions (drought, irrigation, wet). We hypothesized: 1) amendments increase nematode abundance, where compost has a greater positive effect than fertilizer; 2) nematodes respond positively to elevated soil moisture and negatively to drought; 3) effects of amendment and precipitation are interactive, where compost mitigates drought’s effects on nematodes. As expected, compost increased nematode abundance relative to other amendment treatments. However, overall, nematodes were most abundant under ambient precipitation, contrary to expectations. This was due to the precipitation-amendment interaction. While compost and fertilizer had similar positive effects on nematodes under ambient and irrigation, under drought, fertilizer had a negative while compost had a positive effect on nematode abundance compared to the no amendment treatment.

Burn Notice: Using Changepoint Detection Algorithms to Improve Wildfire Tracking

Presenter: Sabrina Reis – Mathematics and Computer Science

Faculty Mentor(s): Weng-Keen Wong

Session: (In-Person) Oral Panel—Fuel, Fire, Grass and Compost

The ability to detect anomalous data is a critical component of any useful statistical analysis, but the process for identifying anomalies can prove time-consuming and arduous. To address these challenges, researchers often delegate data processing to an algorithm, which analyzes data with more speed, efficiency, and accuracy than manual calculations, enabling earlier detection of anomalies. The property of early detection is especially critical when monitoring spatio-temporal events such as wildfires. The critical impact of these events necessitate data sources that provide current and complete information. This need is often met by networks of sensors–for instance, air quality sensors–that collect real-time, localized data. When processed with an anomaly detection algorithm, the comprehensive data collected by sensor networks can reveal aberrations indicative of a spatio- temporal event. To explore how anomaly detection algorithms can facilitate early detection of events of interest using sensor data, we gathered historical data from open-source Purple Air sensors to build case studies of past wildfires. We then applied various types of changepoint detection algorithms to the data in hopes of identifying changes in the distribution of data that indicated a wildfire had broken out. The toolkit of detection methods produced by the project offer a cost-effective and portable way of enhancing our ability to monitor the formation and spread of wildfires.

Nitrogen Fixing Symbionts: Legume Survival and Coexistence in Warming California Grasslands

Presenter: Natalie Kataoka − Environmental Science

Faculty Mentor(s): Carmen Ebel, Ashley Shaw Adams

Session: (In-Person) Oral Panel—Fuel, Fire, Grass and Compost

For the past 200 years, non-native species have been anthropogenically introduced in California grasslands, reducing native species abundance and diversity. Trifolium hirtum is a non-native legume commonly used for cattle fodder and cover cropping because of its ability to fix nitrogen via rhizobial symbionts. T. hirtum currently coexists with California native legume Trifolium willdenovii in established communities, however, T. hirtum has the potential to outcompete T. willdenovii under increased environmental stress, such as that caused by climate change. Considering how symbiotic rhizobia contribute to these Trifolium species’ ability to coexist or compete with other species, as well as how climate change alters these interactions, is essential for understanding potential impacts on native biodiversity and how important forage species react to changing climate conditions.

I tested 1) how rhizobial symbionts contributed to the ability of a native and a non-native legume to coexist with each other and other species in the community. And 2) how drought influences competitive relationships between the two legumes. For both non-native T. hirtum and native T. willdenovii, I measured rhizobia nodule mass, seeded background count, weed species counts, and weighed the aboveground biomass on individuals grown under drought and ambient precipitation treatments. On average, there were no differences in the mass of rhizobia nodules by species, however there was an observed correlation between the biomass and nodule mass of uninoculated background T. willdenovii. Drought positively impacted the biomass of background T. hirtum individuals, however drought treatments negatively affected focal T. hirtum biomass compared to ambient precipitation. Drought had no significant effect on focal T. willdenovii biomass.

Monitoring Fuel Treatment Efficacy in Oak Habitat at Suzanne Arlie Park

Presenter: Zoey Bailey − Family and Human Services

Co-Presenter(s): Hans Bertelsen, Isabel Mosley, Alex Murphy

Faculty Mentor(s): Peg Boulay

(In-Person) Oral Panel—Fuel, Fire, Grass and Compost

Upland oak prairies and oak savannas are scarce within Oregon’s Willamette Valley. In order to restore these fire-dependent communities, we must integrate prescribed fire and land stewardship practices. Our team has been working closely with the City of Eugene Parks and Open Spaces Department to collect vegetation data to evaluate the effects of fuels management at Suzanne Arlie Park. Project goals are to conduct vegetation monitoring and evaluate fuel loads within plots that have been untreated or treated with herbicide, mastication, mowing, and prescribed burns. A paramount aspect of our team’s protocol is to collect data on species composition and richness, which is key for management decisions such as prescribed fire. We have used a nested plot design: determining the plot center using randomized methods, measuring and describing trees and large woody fuels present within a 1/100th acre plot, measuring shrub cover along a 50 ft transect, and describing herbaceous cover and small woody fuels in three 1 m2 quadrats. Site awareness parameters consisted of photo monitoring points and qualitative assessment with comments. Our findings will be used to make management recommendations to the City of Eugene for Suzanne Arlie Park and the Ridgeline Trail System. These recommendations will be used to implement fuels reduction treatments; restore, enhance, and promote awareness of native habitats; and will increase collaboration across parks within Eugene’s Wildland-Urban Interface.