The identification of Feix and Nixi in the solar corona

The levels of the configuration 3s ²3 _p ⁵3d of Fe ix have been experimentally determined from their combinations with 3s3 _p ⁶3d ³ D in the region 300–400 Å. Wavelengths can now be accurately predicted for all transitions within 3s ²3 _p 53^d, and eight of these can be identified with coronal lines from 2042 to 4585 Å. Also, identifications of solar lines from 171 to 245 Å with electric-dipole and magnetic-quadrupole transitions to the ground state, 3s ²3p ^{6 1} S, are confirmed and extended. Solar identifications with corresponding transitions in Ni xi, both within 3s ²3 _p ⁵3d and to the ground state, are proposed on the basis of a short extrapolation.     

Development and Application of a Method to Identify Salt Marsh Vulnerability to Sea Level Rise

Wetlands are commonly assessed for ecological condition and biological integrity using a three-tiered framework of landscape-scale assessment, rapid assessment protocols, and intensive biological and physiochemical measurements. However, increased inundation resulting from accelerated sea level rise (SLR) is negatively impacting tidal marsh ecosystem functions for US Northeast coastal wetlands, yet relative vulnerability to this stressor is not incorporated in condition assessments. This article assesses tools available to measure coastal wetland vulnerability to SLR, including measurements made as part of traditional rapid condition assessments (e.g., vegetation communities, soil strength), field and remote sensing-based measurements of elevation, VDatum, and Sea Level Affecting Marshes Model (SLAMM) model outputs. A vulnerability metric that incorporates these tools was calibrated and validated using recent rates of marsh vegetation losses (1972–2011) as a surrogate for future vulnerability. The metric includes complementary measures of elevation capital, including the percentage of high vs. low marsh vegetation, Spartina alterniflora height, elevation measurements, and SLAMM outputs that collectively explained 62% of the variability in recent rates of marsh vegetation loss. Stepwise regression revealed that all three elements (elevation, vegetation measures, and SLAMM outputs) explained significant and largely unique components of vulnerability to SLR, with the greatest level of overlap found between SLAMM outputs and elevation metrics. While soil strength varied predictably with habitat zone, it did not contribute significantly to the vulnerability metric. Despite the importance of determining wetland elevation above key tidal datums of mean sea level and mean high water, we caution that VDatum was found to perform poorly in back-barrier estuaries. This factor makes it difficult to compare elevation capital among marshes that differ in tidal range and poses accuracy problems for broad-scale modeling efforts that require accurate tidal datums. Given the pervasive pattern of coastal wetland drowning occurring in the Northeastern USA and elsewhere, we advocate that compilation of regional data on marsh habitats and vulnerability to SLR is crucial as it permits agencies to target adaptation to sites based on their vulnerability or mixture of habitats, it helps match sites to appropriate interventions, and it provides a broader regional context to site-specific management actions. Without such data, adaptation actions may be implemented where action is not necessary and to the disadvantage of vulnerable sites where opportunities for successful adaptation will be missed.     

Vegetation Dynamics in Rhode Island Salt Marshes During a Period of Accelerating Sea Level Rise and Extreme Sea Level Events

Sea level rise is a major stressor on many salt marshes, and its impacts include creek widening, ponding, vegetation dieback, and drowning. Marsh vegetation changes have been associated with sea level rise across southern New England, but most of these studies pre-date the current period of rapidly accelerating sea level rise coupled with episodic events of extreme increases in water levels. Here, we combine data from two salt marsh monitoring and assessment programs in Rhode Island that were designed to assess marsh responses to sea level rise and use these data to document temporal and spatial patterns in marsh vegetation during the current period of extreme water level increases. Vegetation monitoring at two Narragansett Bay salt marshes confirms the ongoing decline of the salt meadow species Spartina patens during this period as it becomes replaced by Spartina alterniflora. Bare ground resulting from vegetation dieback was significantly related to mean high water levels and led to the rapid conversion of mixed Spartina assemblages to S. alterniflora monocultures. A broader spatial assessment of RI marshes shows that S. alterniflora dominance increases at lower elevation marshes toward the mouth of Narraganset Bay. Our data provide additional evidence that S. patens continues to decline in southern New England marshes and show that losses can accelerate during periods of extreme high water levels. Unless adaptive management actions are taken, we predict that marshes throughout RI will continue to lose salt meadow habitat and eventually resemble lower elevation marshes that are already dominated by S. alterniflora monocultures.     

Sorption of Iron on Surfaces: Modelling,Data Evaluation,and Measurement Uncertainty

Assessment of the likely outcome of engineered invention strategies in acid mine drainage often involves complex geochemical modelling activities. Geochemical modelling is based on chemical thermodynamic data. In addition sorption models, kinetical reaction rates and transport tools are included into the modelling codes because the interactions between solution components and surfaces, reaction time and transport are considered important features characterising the site‐specific situation. In the determination of both thermodynamic data and sorption coefficients, speciation calculations play an important role. By applying the probabilistic speciation code Ljungskile to some simplified acid mine drainage scenarios, the strong impact of chemical speciation on the complete measurement uncertainty budget of geochemical modelling predictions is shown. The complete measurement uncertainty budget in combination with other metrological concepts like traceability is an essential element of quality assurance for experimental data. The elements of quality assurance are provided by international agreements and normative documents on national and international levels. The following discussion will focus on some metrological issues of sorption data.