In Sierra Nevada forests, shrubs are considered strong soil moisture competitors with regenerating trees, reducing seedling establishment, and
slowing growth. Recent studies, however, suggest that in some circumstances shrubs can facilitate tree establishment and growth by modifying
harsh microclimate conditions; increasing acquisition of water, carbon, and/or nutrients via shared mycorrhizal...
In Sierra Nevada forests, shrubs are considered strong soil moisture competitors with regenerating trees, reducing seedling establishment, and
slowing growth. Recent studies, however, suggest that in some circumstances shrubs can facilitate tree establishment and growth by modifying
harsh microclimate conditions; increasing acquisition of water, carbon, and/or nutrients via shared mycorrhizal...
Nitrogen is a limiting resource in many temperate forests and nitrogen-fixing plants are usually limited to the early
stages of post-disturbance succession. In fire-dependent Sierra Nevada forests, however, Ceanothus cordulatus is
relatively abundant even in old-growth forest conditions which are at least partly maintained by fire.We conducted
a field experiment...
Nitrogen is a limiting resource in many temperate forests and nitrogen-fixing plants are usually limited to the early stages of post-disturbance succession. In fire-dependent Sierra Nevada forests, however, Ceanothus cordulatus is relatively abundant even in old-growth forest conditions which are at least partly maintained by fire. We conducted a field...
Sierra Nevada forests have high understory species richness yet we do not know which site factors influence
herb and shrub distribution or abundance. We examined the understory of an old-growth mixed-conifer
Sierran forest and its distribution in relation to microsite conditions. The forest has high species richness
(98 species sampled),...
Frankia strains symbiotic with Ceanothus present an interesting opportunity to study the patterns and causes of Frankia diversity and distribution within a particular host infectivity group. We intensively sampled Frankia from nodules on Ceanothus plants along an elevational gradient in the southern Sierra Nevada of California, and we also collected...
Little is known about biophysical controls on soil respiration in California’s Sierra Nevada oldgrowth, mixed-conifer forests. Using portable and automated soil respiration sampling units, we measured soil respiration rate (SRR) in three dominant patch types: closed canopy (CC), ceanothus-dominated patches (CECO), and open canopy (OC). SRR varied significantly among the...
With fire suppression, many western forests are expected to have fewer gaps
and higher stem density of shade-tolerant species as light competition becomes a more
significant influence on stand pattern and composition. We compared species composition,
structure, spatial pattern, and environmental factors such as light and soil moisture between
two...
Experimental manipulation of the symbiosis between cnidarians and photosynthetic dinoflagellates (Symbiodinium spp.) is crucial to advancing the understanding of the cellular mechanisms involved in host-symbiont interactions, and overall coral reef ecology. The anemone Aiptasia sp. is a model for cnidarian-dinoflagellate symbiosis, and notably it can be rendered aposymbiotic (i.e. dinoflagellate-free)...
Detailed analysis of mixed-conifer and red fir forests were made from extensive, large vegetation sampling, systematically conducted throughout the Teakettle Experimental Forest. Mixed conifer is characterized by distinct patch conditions of closed-canopy tree clusters, persistent gaps and shrub thickets. This heterogeneous spatial structure provides contrasting microclimate, habitat and resource conditions...