Establishment of Native Vegetation for Erosion Control on the Cal Poly, San Luis Obispo, Campus.

When applied to a bare slope, vegetation and mulch will prevent further erosion and enhance the aesthetic appeal of the area, ultimately improving the quality of the soil. If nothing is done to this barren slope, its condition will continue to deteriorate. Core samples were taken at six different sites located on a highly degraded and barren slope on the Cal Poly campus. Bulk density, porosity, soil temperature, and nitrogen and phosphorous levels were measured prior to vegetating the slope. Thirty-three groundcover rose bushes were planted and drip irrigation was installed. Mulch was laid down and two un-official coarse-sand walking trails were constructed to direct foot traffic. After a period of three months, core samples were taken again at each of the six sites, and the measurements were repeated. We expected the condition of the slope to be much improved, with minimal erosion and increased aesthetic value. The bulk density decreased and porosity increased. Decomposition of the mulch and vegetative growth added organic matter to the soil. The benefits of such improvement to the soil will be enhanced water quality of the runoff that flows into the sewer drains and an educational opportunity for all who participate in the project and observe the site as they walk to class

Human factors considerations in control room modernization: Trends and personnel performance issues

Advanced human-system interface (HSI) technology is being integrated into existing nuclear plants as part of plant modifications and upgrades. The result of this trend is that hybrid HSIs are created, i.e., HSIs containing a mixture of conventional (analog) and advanced (digital) technology. The purpose of the present research is to define the potential effects of hybrid HSIs on personnel performance and plant safety and to develop human factors guidance for safety reviews of them where necessary. In support of this objective, human factors topics associated with hybrid HSIs were identified. A human performance topic is an aspect of hybrid HSIs, such as a design or implementation feature, for which human performance concerns were identified. The topics were then evaluated for their potential significance to plant safety. Twelve topics were identified as potentially safety significant issues, i.e., their human performance concerns have the potential to compromise plant safety. The issues were then prioritized and a subset was selected for design review guidance development. 6 refs

Comparative transcriptomics reveals altered species interaction between the bioeroding sponge Cliona varians and the coral Porites furcata under ocean acidification

Bioeroding sponges interact and compete with corals on tropical reefs. Experimental studies have shown global change alters this biotic interaction, often in favour of the sponge. Ocean acidification in particular increases sponge bioerosion and reduces coral calcification, yet little is known about the molecular basis of these changes. We used RNA-Seq data to understand how acidification impacts the interaction between the bioeroding sponge, Cliona varians, and the coral, Porites furcata, at the transcriptomic level. Replicate sponge and coral genets were exposed to ambient (8.1 pH) and acidified (7.6 pH) conditions in isolation and in treatments where they were joined for 48 h. The coral had a small gene expression response (tens of transcripts) to the sponge, suggesting it does little at the transcriptomic level to deter sponge overgrowth. By contrast, the sponge differentially expressed 7320 transcripts in response to the coral under ambient conditions and 3707 transcripts in response to acidification. Overlap in the responses to acidification and the coral, 2500 transcripts expressed under both treatments, suggests a similar physiological response to both cues. The sponge expressed 50× fewer transcripts in response to the coral under acidification, suggesting energetic costs of bioerosion, and other cellular processes, are lower for sponges under acidification. Our results suggest how acidification drives ecosystem-level changes in the accretion/bioerosion balance on coral reefs. This shift is not only the result of changes to the thermodynamic balance of these chemical reactions but also the result of active physiological responses of organisms to each other and their abiotic environment

Genetic diversity and gene flow in Zostera marina populations surrounding Long Island, New York, USA: no evidence of inbreeding, genetic degradation or population isolation

Since the 1930s, eelgrass around Long Island, New York, USA, has experienced significant ecological and anthropogenic disturbances reducing areal coverage of the species. Patchiness, low density or isolation of these remaining populations increase susceptibility of this aquatic angiosperm to extinction. The loss of genetic diversity and patch connectivity, may contribute to lower fitness of eelgrass thus affecting recovery potential. Previous studies of eelgrass populations around Long Island report genetically isolated populations with low diversity. In contrast, this study found neither the evidence of inbreeding nor indications of genetic degradation for the same populations. Measures of genetic diversity such as average alleles (A=7.59) and fixation index (F=0.02) suggest no significant impediments to genetic connectivity among populations sampled. Gene flow (Nm=4.58) and bottleneck analyses suggest the major disturbances of the past have not strongly affected population structure in the Long Island system. These findings have significant implications for both management and restoration. Locally, eelgrass populations in Long Island waters are unlikely to decline through genetic erosion or inbreeding processes alone. Plants from within these populations possess adequate genetic diversity to undertake restoration activities. On a larger geographic scale, the ability of these plants to maintain such high levels of genetic diversity and connectivity despite the significant areal losses historically provides optimism for the recovery potential of this species despite recent global losses. © 2013 Elsevier B.V.Bradley J. Peterson, Eric Bricker, Sterling J. Brisbin, Bradley T. Furman, Amber D. Stubler, John M. Carroll, Dianna L. Berry, Christopher J. Gobler, Ainsley Calladine, Michelle Waycot