Open Access. Powered by Scholars. Published by Universities.®

Life Sciences Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 4 of 4

Full-Text Articles in Life Sciences

Limits To Sexual Reproduction In Geothermal Bryophytes, Sarah M. Eppley, Todd N. Rosenstiel, Camille Brianne Graves, Estefanía Llaneza García Sep 2011

Limits To Sexual Reproduction In Geothermal Bryophytes, Sarah M. Eppley, Todd N. Rosenstiel, Camille Brianne Graves, Estefanía Llaneza García

Biology Faculty Publications and Presentations

Previous research suggests that while sexual reproduction generally increases with environmental stress it may decrease with extreme stress, at the edge of eukaryotic life. In this study, we explored the limits to sexual reproduction in an extremophile, bryophyte system to ultimately understand the processes that limit sexual reproduction. We used field data from geothermal sites at Lassen Volcanic National Park, California, to demonstrate that sexual reproduction, as measured by the number of sporophytes per shoot, decreases with increasing environmental stress. We found that the number of sporophytes per shoot is positively correlated with distance from geothermal features. When Pohlia nutans …


Multiple And Long-Term Effects Of An Introduced Predatory Crab, Catherine E. De Rivera, Edwin D. Grosholz, Gregory M. Ruiz May 2011

Multiple And Long-Term Effects Of An Introduced Predatory Crab, Catherine E. De Rivera, Edwin D. Grosholz, Gregory M. Ruiz

Environmental Science and Management Faculty Publications and Presentations

Despite the importance of invasions, few studies have explored their long-term consequences in marine systems or examined multiple types of population-level effects. Initial effects, however, may not persist over longer time frames; effects have been shown to wane in freshwater systems. We combined 14 yr of field surveys (1993 to 2006) with manipulative experiments to examine the potential for multiple effects of a nonindigenous crab Carcinus maenas on the native shore crab Hemigrapsus oregonensis over time in central California. H. oregonensis abundance was negatively correlated with C. maenas abundance. However, H. oregonensis abundance rebounded to pre-invasion levels once C. maenas …


The Aquarium Trade As An Invasion Pathway In The Pacific Northwest, Angela L. Strecker, Philip M. Campbell, Julian D. Olden Apr 2011

The Aquarium Trade As An Invasion Pathway In The Pacific Northwest, Angela L. Strecker, Philip M. Campbell, Julian D. Olden

Environmental Science and Management Faculty Publications and Presentations

The aquarium trade moves thousands of species around the globe, and unwanted organisms may be released into freshwaters, with adverse ecological and economic effects. We report on the first investigation of the ornamental pet trade as an invasion pathway in the Pacific Northwest region of the United States, where a moderate climate and a large human population present ample opportunities for the introduction and establishment of aquarium trade species. Results from a regional survey of pet stores found that the number of fish (n=400) and plant (n=124) species currently in the aquarium trade is vast. Pet stores import thousands of …


Structuring Expert Input For A Knowledge-Based Approach To Watershed Condition Assessment For The Northwest Forest Plan, Usa, Sean N. Gordon, Kirsten Gallo Jan 2011

Structuring Expert Input For A Knowledge-Based Approach To Watershed Condition Assessment For The Northwest Forest Plan, Usa, Sean N. Gordon, Kirsten Gallo

Institute for Sustainable Solutions Publications and Presentations

Assessments of watershed condition for aquatic and riparian species often have to rely on expert opinion because of the complexity of establishing statistical relationships among the many factors involved. Such expert-based assessments can be difficult to document and apply consistently over time and space. We describe and reflect on the process of developing a computer-based decision support application from expert judgments for assessing aquatic and riparian conditions over the 100,000 km2 managed by the US federal government under the Northwest Forest Plan. The decision support system helped structure and document the assessment process and provided consistency and transparency to the …