In response to the recent expansion of piñon and juniper woodlands into sagebrush-steppe communities in the northern Great Basin region, numerous conifer-removal projects have been implemented, primarily to release understory vegetation at sites having a wide range of environmental conditions. Responses to these treatments have varied from successful restoration of...
Current paradigm suggests that spatial and temporal competition for resources limit an exotic invader, cheatgrass (Bromus
tectorum L.), which once established, alters fire regimes and can result in annual grass dominance in sagebrush steppe.
Prescribed fire and fire surrogate treatments (mowing, tebuthiuron, and imazapic) are used to reduce woody fuels...
Managers reduce piñon (Pinus spp.) and juniper (Juniperus spp.) trees that are encroaching on sagebrush (Artemisia spp.)
communities to lower fuel loads and increase cover of desirable understory species. All plant species in these communities
depend on soil water held at >-1.5 MPa matric potential in the upper 0.3 m...
Invasion and dominance of exotic grasses and increased fire frequency threaten native ecosystems worldwide. In the Great Basin region of the western United States, woody and herbaceous fuel treatments are implemented to decrease the effects of wildfire and increase sagebrush (Artemisia spp.) ecosystem resilience to disturbance and resistance to exotic...
In sagebrush ecosystems invasion of annual exotics and expansion of piñon (Pinus monophylla Torr. and Frem.) and juniper
(Juniperus occidentalis Hook., J. osteosperma [Torr.] Little) are altering fire regimes and resulting in large-scale ecosystem
transformations. Management treatments aim to increase resilience to disturbance and enhance resistance to invasive species by...
Piñon (Pinus spp.) and juniper (Juniperus spp.) trees are reduced to restore native vegetation and avoid severe fires where they have expanded into sagebrush (Artemisia tridentata Nutt.) communities. However, what phase of tree infilling should treatments target to retain desirable understory cover and avoid weed dominance? Prescribed fire and tree...
Several studies in recent years have demonstrated that upper-division students struggle with the
mathematics of thermodynamics. This paper presents a task analysis based on several expert attempts
to solve a challenging mathematics problem in thermodynamics. The purpose of this paper is twofold.
First, we highlight the importance of cognitive task...
We investigate the value of the correlation function of an inhomogeneous hard-sphere fluid at contact. This quantity plays a critical role in statistical associating fluid theory, which is the basis of a number of recently developed classical density functionals. We define two averaged values for the correlation function at contact...
A stream's temperature is a major factor in its ability to support
fish life and to be utilized for other beneficial purposes. The
approach most generally used for stream temperature prediction is
the Energy-Budget method, which involves the inventory of all the
energy entering and leaving the stream. A temperature...
Microbial populations associated with the major substrates of the
canopy of a 70 m old-growth Douglas fir were studied to determine
potential activities. Seasonal samples from bark, foliage, epiphytic
moss, lichens, and litter accumulations were collected to i) obtain
population data, ii) to isolate the major groups of microorganisms
present,...