Tidal events and salt-marsh structure influence black mangrove (Avicennia germinans) recruitment across an ecotone

Field experiments were conducted at a black mangrove-salt-marsh ecotone in southwest Florida (U.S.A.) to investigate retention of propagules of the black mangrove, Avicennia germinans, by salt-marsh plants as a mechanism of facilitation operating on recruitment success at landward boundaries. Buoyant A. germinans propagules are dispersed by tides, and stranding is required for establishment; therefore, processes that enable stranding should facilitate mangrove recruitment. We expected the physical structure of salt-marsh vegetation to define propagule retention capacity, and we predicted that salt-marsh plants with distinct growth forms would differentially retain propagules. Experimental monoculture plots (1 m2) of salt-marsh plants with different growth forms (Sporobolus virginicus [grass], Sesuvium portulacastrum [succulent forb], and Batis maritima [succulent scrub]) were created, and A. germinans propagules were emplaced into these plots and monitored over time. For comparison, propagules were also placed into natural polyculture plots (1 m2). Polyculture plots contained at least two of the salt-marsh plant taxa selected for monoculture treatments, and S. virginicus was always present within these polyculture plots. Natural polyculture plots retained 59.3% +/- 11.0% (mean +/- SE) of emplaced propagules. Monocultures varied in their propagule retention capacities with plots of S. virginicus retaining on average 65.7% +/- 11.5% of transplanted propagules compared to 7.2% +/- 1.8% by B. maritima and 5.0% +/- 1.9% by S. portulacastrum. Plots containing S. virginicus retained a significantly greater percentage of emplaced propagules relative to the two succulent salt-marsh taxa. Furthermore, propagule entrapment, across all treatments, was strongly correlated with salt-marsh structure (r2 = 0.6253, P = 0.00001), which was estimated using an indirect quantitative metric (lateral obstruction) calculated from digital images of plots. Overall, our findings imply that entrapment of propagules by salt-marsh plants may be facilitative if propagules are dispersed beyond the established tree line by spring or storm tides, and that facilitation may be sustained over time. We conclude that salt-marsh ecotone permeability may modulate landward encroachment by A. germinans, and that interactions among the early life history stages of black mangroves and neighboring plants may direct community responses to climate change.     

An insect parasitoid carrying an ochratoxin producing fungus

The insect parasitoid Prorops nasuta has been introduced from Africa to many coffee-producing countries in an attempt to control the coffee berry borer. In this paper, we report on the sequencing of the ITS LSU-rDNA and beta-tubulin loci used to identify a fungus isolated from the cuticle of a P. nasuta that emerged from coffee berries infected with the coffee berry borer. The sequences were compared with deposits in GenBank and the fungus was identified as Aspergillus westerdijkiae. The fungus tested positive for ochratoxin A production, with varying levels depending on the media in which it was grown. These results raise the possibility that an insect parasitoid might be disseminating an ochratoxin-producing fungus in coffee plantations.     

Sorption mechanisms of cephapirin, a veterinary antibiotic, onto quartz and feldspar minerals as detected by Raman spectroscopy

Raman spectroscopy was used to investigate sorption mechanisms of cephapirin (CHP), a veterinary antibiotic, onto quartz (SiO₂) and feldspar (KAlSi₃O₈) at different pH. Sorption occurs by electrostatic attraction, monodentate and bidentate complexation. The zwitterion (CHP^o) adsorbs to a quartz⁽⁺⁾ surface by electrostatic attraction of the carboxylate anion group (-COO⁻) at low pH, but adsorbs to a quartz⁽⁻⁾ surface through electrostatic attraction of the pyridinium cation, and possibly COO⁻ bridge complexes, at higher pH. CHP⁻ bonds to quartz⁽⁻⁾ surfaces by bidentate complexation between one oxygen of -COO⁻ and oxygen from carbonyl of an acetoxymethyl group. On a feldspar^(+/−) surface, CHP^o forms monodentate complexes between CO, and possible -COO⁻ bridges and/or electrostatic attachments to localized edge (hydr)oxy-Al surfaces. CHP⁻ adsorbs to feldspar⁽⁻⁾ through monodentate CO complexation. Similar mechanisms may operate for other cephalosporins. Results demonstrate, for the first time, that Raman techniques can be effective for evaluating sorption mechanisms of antibiotics.     

PM2.5 speciation trends network: evaluation of whole-system uncertainties using data from sites with collocated samplers

The objectives of this paper are to contrast the relative variability of replicate laboratory measurements of selected chemical components of fine particulate matter (PM) with total variability from collocated measurements and to compare the magnitudes of the uncertainties determined from collocated sampler data with those currently being provided to U.S. Environmental Protection Agency (EPA)'s Air Quality System (AQS) database by RTI International (RTI). Pointwise uncertainty values are needed for modeling and data analysis and should include all the random errors affecting each data point. Total uncertainty can be decomposed into two primary components: analytical measurement uncertainty and sampling uncertainty. Analytical measurement uncertainties are relatively easy to calculate from routine quality control (QC) data. Sampling uncertainties, on the other hand, are comparatively difficult to measure. In this paper, the authors describe data from collocated samplers to provide a snapshot of whole-system uncertainty for several important chemical species. The components of uncertainty were evaluated for key species from each of the analytical methods employed by the PM2.5 Speciation Trends Network (STN) program: gravimetry, ion chromatography (IC), X-ray fluorescence (XRF), and thermal-optical analysis for organic carbon and elemental carbon. The results show that the laboratory measurement uncertainties are typically very small compared with uncertainties calculated from the differences between samples collected from collocated samplers. These differences are attributable to the "field" components uncertainty, which may include contamination and/or losses during shipping, handling, and sampling, as well as other distortions of the concentration level due to flow and sample volume variations. Uncertainties calculated from the collocation results were found to be generally similar to the uncertainties currently being loaded into EPA's AQS system, with some exceptions described below.     

Institutional capacity for long-term climate change adaptation: evidence from land use planning in Albay,Philippines

Mainstreaming climate change adaptation (CCA) into plans and programs is still a new approach in adaptation and thus there is limited information on how to operationalize it on-ground. This paper addresses this gap by investigating the challenges in mainstreaming CCA into the local land use plans in the province of Albay, Philippines. Specifically, this paper developed 20 quantitative “mainstreaming indicators” to assess the state-of-play and the challenges for local mainstreaming. These indicators were classified under three groupings, namely, the information, institutional, and resource capacities of systems. Qualitative analysis of the indicator scores suggested that developing the institutional capacities of local governments is crucial in the local mainstreaming process. Likewise, the results highlighted the “institutional issues” indicator as the primary barrier in operationalizing the approach. These institutional issues are: fragmented laws and regulations; overlapping policy requirements; and the lack of guidelines for mainstreaming CCA into the local land use plans. Meanwhile, the “leadership” indicator, as signified by a climate change champion in Albay, was evaluated as an opportunity for local mainstreaming. The champion effectively led the CCA efforts because the existing institutional mechanisms supported the champion’s capacity to influence the behavior of people and produce collective action towards CCA.     

Effects of Habitat Disturbance from Residential Development on Breeding Bird Communities in Riparian Corridors

This study assessed the relationship among land use, riparian vegetation, and avian populations at two spatial scales. Our objective was to compare the vegetated habitat in riparian corridors with breeding bird guilds in eight Rhode Island subwatersheds along a range of increasing residential land use. Riparian habitats were characterized with fine-scale techniques (used field transects to measure riparian vegetation structure and plant species richness) at the reach spatial scale, and with coarse-scale landscape techniques (a Geographic Information System to document land-cover attributes) at the subwatershed scale. Bird surveys were conducted in the riparian zone, and the observed bird species were separated into guilds based on tolerance to human disturbance, habitat preference, foraging type, and diet preference. Bird guilds were correlated with riparian vegetation metrics, percent impervious surface, and percent residential land use, revealing patterns of breeding bird distribution. The number of intolerant species predominated below 12% residential development and 3% impervious surface, whereas tolerant species predominated above these levels. Habitat guilds of edge, forest, and wetland bird species correlated with riparian vegetation. This study showed that the application of avian guilds at both stream reach and subwatershed scales offers a comprehensive assessment of effects from disturbed habitat, but that the subwatershed scale is a more efficient method of evaluation for environmental management.     

Land-use choices: the case of conservation reserve program (CRP) re-enrollment in Kansas,USA

Among the important alternatives for land conservation is the US Conservation Reserve Program (CRP) that celebrated its 30th anniversary in 2015. This paper explores how landowners decide on alternative land-use choices made available by the expiration of CRP contracts in Kansas. The study uses survey data and multinomial Logit models to predict land-use choices. Two models were tested. The first model does not incorporate variables concerning farmer perceptions and attitudes about land-use choices, while the second model does. The results show that CRP re-enrollment depends on factors, such as years of experience in cropping and percent of cropland irrigated. However, when perception variables are added, the models become more robust in explaining other land choice alternatives. The results suggest that as the perception of unfairness of more inflexible environmental policy rises, these farmers may be more likely to re-enroll their marginal land in the CRP program.     

Modeling the Potential Impacts of Climate Change on Pacific Salmon Culture Programs: An Example at Winthrop National Fish Hatchery

Hatcheries have long been used in an attempt to mitigate for declines in wild stocks of Pacific salmon (Oncorhynchus spp.), though the conservation benefit of hatcheries is a topic of ongoing debate. Irrespective of conservation benefits, a fundamental question is whether hatcheries will be able to function as they have in the past given anticipated future climate conditions. To begin to answer this question, we developed a deterministic modeling framework to evaluate how climate change may affect hatcheries that rear Pacific salmon. The framework considers the physiological tolerances for each species, incorporates a temperature-driven growth model, and uses two metrics commonly monitored by hatchery managers to determine the impacts of changes in water temperature and availability on hatchery rearing conditions. As a case study, we applied the model to the US Fish and Wildlife Service’s Winthrop National Fish Hatchery. We projected that hatchery environmental conditions remained within the general physiological tolerances for Chinook salmon in the 2040s (assuming A1B greenhouse gas emissions scenario), but that warmer water temperatures in summer accelerated juvenile salmon growth. Increased growth during summer coincided with periods when water availability should also be lower, thus increasing the likelihood of physiological stress in juvenile salmon. The identification of these climate sensitivities led to a consideration of potential mitigation strategies such as chilling water, altering rations, or modifying rearing cycles. The framework can be refined with new information, but in its present form, it provides a consistent, repeatable method to assess the vulnerability of hatcheries to predicted climate change.     

Exploring the role of hope in job performance: results from four studies

According to Snyder's hope theory, high hope individuals possess more goal‐related strategies and are more motivated to achieve their goals than their low hope counterparts. Therefore, we examined the relationship between hope and job performance using three different samples of employees of different job levels and industries. We found that more hopeful sales employees, mortgage brokers, and management executives had higher job performance, as measured a year later, even after controlling for their self‐efficacy and cognitive ability. In a fourth study, we examined if more hopeful employees attempt to solve problems differently than do those with less hope. Higher hope management executives produced more and better quality solutions to a work‐related problem, suggesting that hopefulness may help employees when they are confronted with problems and encounter obstacles at work. Copyright © 2007 John Wiley & Sons, Ltd.