Student Poster Contest Results

Congratulations to the winners of the 2009 LTER ASM Student Poster competition.

Predator and pollinator response to flowering strips varies with landscape diversity (1st Place) - J. Megan Woltz

Landscapes provide ecosystem services to agricultural systems by supporting pollinators and predators of crop pests, services valued at $US 3 and $US 4.5 billion/yr respectively. Habitat management is the practice of providing nectar, pollen and shelter to beneficial insects in cropping systems, often in the form of flowering strips. However, the potential for flowering strips to increase biocontrol and pollination depends on the existing abundances of beneficial insects in the landscape, and highly simplified landscapes may support fewer beneficial insects than more diverse landscapes.

Honorable mention
Going Underground: The role of mycorrhizal fungi in promoting or inhibiting post-fire seedling establishment across treeline in Alaska (1st Honorable Mention) - Rebecca Hewitt

Soil microbes are key drivers of ecosystem processes, yet their role in regulating landscape-scale vegetation change is not known. Comprehensive studies of treeline position have noted that ectomycorrhizal fungi may be an important factor delineating the boundary between forest and tundra. Yet, these critical plant-fungal symbioses are sensitive to wildfires. Fire is the primary landscape-scale disturbance in the boreal forest and increasingly important in tundra.

Environmental Influences on the Genetic Diversity of Arctic Stream Bacterial Communities (2nd Honorable Mention) - Julia Larouche

Microbes are of critical importance but are a poorly understood component of arctic stream ecosystems. They are responsible for recycling organic matter and regenerating nutrients that are essential to the food webs of aquatic ecosystems. We tested the hypothesis that differences in highly contrasting parent lithologies (non-carbonate and ultramafic), stream habitat (sediments and rocks), and stream biogeochemistry influence the structure of bacterial biofilm communities in arctic streams.

Convergence of microbial community function in common environments is associated with loss of function in alternate environments (3rd Honorable Mention) - Ashley Keiser

Soil microbial communities play a pivotal role in providing ecosystem services, given that they are key drivers of biogeochemical processes such as carbon and nitrogen cycling. As species-rich communities, made-up of populations with short generation times, it is commonly assumed that there is a high degree of functional redundancy within soil communities with respect to broad-physiological processes, such as organic carbon decomposition.

Predicting community response to N-enrichment with SLA: a multisystem test. (4th Honorable Mention - Tie) - Marko Spasojevic

Human activities have increased the amount of available nitrogen (N) globally. Increased N-availability can change plant community structure and function, and lead to diversity loss. Species traits associated with differential resource limitation may predict how plant communities will respond to N-enrichment across ecosystems. We focused on specific leaf area (SLA), leaf area per unit leaf mass, as a candidate trait because it is correlated with high relative growth rates, photosynthetic rates, and leaf N-concentrations.

Separation of river network scale nitrogen removal among the main channel and two transient storage compartments (4th Honorable Mention - Tie) - Robert Stewart

Reach scale experiments have shown that transient storage (TS) zones may be important controls on nitrogen (N) export to coastal waters. We investigated the relative impact that main channel (MC), surface TS (STS) and hyporheic TS (HTS) have on N removal at the network scale using an N removal model applied to the Ipswich River in Massachusetts, USA.