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Wetlands around the world are under threat from habitat destruction and degradation. In theUnited States, the Clean Water Act is the primary tool used to regulate impacts to wetlands. TheU.S. Army Corps of Engineers (USACE) regulates Section 404 of the CWA, which allows forimpacts to wetlands with appropriate compensatory mitigation. While permanent impacts andcompensatory mitigation have been studied by researchers, temporary impacts to wetlands havenot been examined. Temporary impacts to wetlands include any activity that temporarilydischarges material into a wetland such as building a temporary access road, temporary waterdiversions, or excavating within a wetland to replace a pipe. This dissertation examines thenature, extent, and location of temporary impacts to wetlands in the southwestern United States and whether they are recovering to pre-construction conditions. First, we showed that hundredsto thousands of temporary impacts to wetlands are authorized each year within our study area ofthe Los Angeles District of USACE. Within our permit sampling, most (50%) of the temporaryimpacts were associated with construction activities, followed by sediment removal (17%).Nearly all sampled permits had a condition associated with the permit to restore the temporaryimpact to pre-project conditions, but only 20% were required to monitor the restoration of thetemporary impact. Next, we used high resolution aerial imagery to assess hydrologic andvegetation recovery from temporary impacts from permits authorized in 2011. Vegetation coverof the impact site did not recover to 100% of pre-impact levels in 40% of our dataset. The overallriparian area recovery varied depending on the metric. From our analysis of 56 projects, four ofthe six metrics used had at least one site never recover and several sites that only slightlyrecovered. Sites with temporary impacts that never recover would be permanent rather thantemporary impacts to wetlands. Finally, we analyzed permits from the past ten years for the landcover types in which the projects occurred. Between 63% and 74% of temporary impacts towetlands were in natural lands and were individually small in impact size. We also specificallyexamined long, linear projects, which accounted for a disproportionate number of the impacts towetlands in natural lands, but they were very small in total hectares. Given the hundreds tothousands of temporary impacts to wetlands permitted in this region each year, that 40% of ourdataset did not fully recover vegetation cover, and only 20% of permits in our study hadconditions to monitor the recovery of the temporary impacts, the USACE should update itsregulations. Specifically, they should define how long an impact can occur while still beingconsidered temporary, increase required monitoring of temporary impacts, and treat temporary impacts as permanent if they do not fully recover, requiring the necessary compensatorymitigation.

California’s coastal wetlands provide valuable ecosystem services to the environment, including sequestering carbon, improving water quality, and providing habitat for many endangered species. Yet due to sea level rise the future of coastal wetlands is in question. Sediment placement is a new and promising technique that aims to help coastal wetlands combat sea level rise. We measured suspended sediment concentrations (SSC) and volatile suspended solids (VSS) at the marsh surface of experimental and control sites one week, one month, three months, six months, and one year after sediment addition. SSC on the experimental and control sites was initially high, but then it decreased and remained low. VSS was lower at the experimental site than the control site for the first three sampling periods and similar for the remainder of the year. This is the first study to evaluate SSC and VSS changes associated with sediment placement.

This poster compares different privileging systems for research data management in terms of their ability to produce HIPAA-compliant data access schemes, their maintenance by non-technical users, and their acceptance at a research center with nearly 100 users. The authors find find that a single database role with automatically assigned permissions based on lab and study membership was both superior and preferable to a solution in which distinct roles must be created for each access level. Find out more about RexDB at http://www.rexdb.org, or download the source code at http://www.bitbucket.org/rexdb.

The Modified Checklist for Autism in Toddlers, Revised, with Follow-up (M-CHAT-R/F) is a questionnaire used widely by health professionals to identify toddlers at risk for Autism Spectrum Disorder (ASD). This poster describes how Prometheus Research developed a secure, standalone, web-based version of the questionnaire and scoring algorithm that allows 1) parents to complete the form at home or at the doctor’s office; 2) doctors to review the results, discuss them with the parent, and follow-up on those with increased risk for developing ASD; and 3) researchers to aggregate the results across 10+ clinics. Find out more about RexDB at http://www.rexdb.org, or download the source code at http://www.bitbucket.org/rexdb.