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Current trends in the global climate facilitate the displacement of numerous marine species from their native distribution ranges to higher latitudes when facing warming conditions. In this work, we analyzed occurrences of a circumtropical reef fish, the spotfin burrfish, Chilomycterus reticulatus (Linnaeus, 1958), in the Madeira Archipelago (NE Atlantic) between 1898 and 2021. In addition to available data sources, we performed an online survey to assess the distribution and presence of this species in the Madeira Archipelago, along with other relevant information, such as size class and year of the first sighting. In total, 28 valid participants responded to the online survey, georeferencing 119 C. reticulatus sightings and confirming its presence in all archipelago islands. The invasiveness of the species was screened using the Aquatic Species Invasiveness Screening Kit. Five assessments rated the fish as being of medium risk of establishing a local population and becoming invasive. Current temperature trends might have facilitated multiple sightings of this thermophilic species in the Madeira Archipelago. The present study indicates an increase in C. reticulatus sightings in the region. This underlines the need for updated comprehensive information on species diversity and distribution to support informed management and decisions. The spread of yet another thermophilic species in Madeiran waters provides further evidence of an ongoing tropicalization, emphasizing the need for monitoring programs and the potential of citizen science in complementing such programs.

Massive, long-lived deep-sea red tree corals (Primnoa pacifica) form a solid, layered axis comprised of calcite and gorgonin skeleton. They are abundant on the outer continental shelf and upper slope of the Northeast Pacific, providing habitat for fish and invertebrates. Yet, their large size and arborescent morphology makes them susceptible to disturbance from fishing activities. A better understanding of their growth patterns will facilitate in-situ estimates of population age structure and biomass. Here, we evaluated relationships between ages, growth rates, gross morphological characteristics, and banding patterns in 11 colonies collected from depths of ~141–335 m off the Alaskan coast. These corals ranged in age from 12 to 80 years old. They grew faster radially (0.33–0.74 mm year-1) and axially (2.41–6.39 cm year-1) than in previously measured older colonies, suggesting that growth in P. pacifica declines slowly with age, and that basal diameter and axial height eventually plateau. However, since coral morphology correlated with age in younger colonies (< century), we developed an in-situ age estimation technique for corals from the Northeast Pacific Ocean providing a non-invasive method for evaluating coral age without removing colonies from the population. Furthermore, we determined that annual bands provided the most accurate means for determining coral age in live-collected corals, relative to radiometric dating. Taken together, this work provides insight into P. pacifica growth patterns to inform coastal managers about the demographics of this ecologically important species. With this new ability to estimate the age of red tree corals in-situ, we can readily determine the age-class structure and consequently, the maturity status of thickets, using non-invasive video survey techniques when coupled with mensuration systems such as lasers or stereo-cameras. Enhanced surveys could identify which populations are most vulnerable to disturbance from human activities, and which should be highlighted for protection.

Tropical and subtropical mangrove swamps, under normal conditions, can sequester large amounts of carbon in their soils but as coastal wetlands, they are prone to hurricane disturbances. This study adds to the understanding of carbon storage capabilities of mangrove wetlands and explores how these capacities might change within the scope of a changing storm climate. In September 2017, Naples Bay, FL, USA (28°5′ N, 81°47′ W) encountered a direct hit from hurricane Irma, a Saffir–Simpson category 3 storm. By comparing carbon storage, forest community structure, and aboveground productivity collected in 2013 and in 2019, we estimated the effects of hurricane Irma on mangrove functions. Aboveground biomass increased during the study period at a rate of approximately 0.72 kg m−2 yr−1, significantly less than the average found in undisturbed mangrove forests. Soil carbon storage decreased at all study sites. On average, 2.7 kg-C m−2 was lost in the top 20 cm between sample collections. Carbon loss in belowground pools could point to a feedback of mangrove swamps on climate change as they lose their ability to store carbon and increase net atmospheric carbon. Nevertheless, mangrove swamps remain resilient to tropical storms in the long term and can recover their carbon storage capacity in the years following a storm.

This paper deals with an experimental study of angled fish-friendly trash racks with horizontal bars, using a physical model in an open channel. Head losses are investigated for 2 bar shapes, 3 ratios between bar spacing and bar thickness and 4 rack’s angles of orientation. The Froude and bar-Reynolds numbers were respectively 0.275 and 3600. The head loss coefficients decrease as the blockage ratio and the angle of orientation of the rack decrease. They are well predicted by the formula produced by Raynal et al. (2013a) for inclined rack with some adaptations. Velocity fields are characterized upstream and downstream of the racks, showing no effect of the angle of orientation and no heterogeneity over channel width. Consequently, the normal and tangential components of the velocity along the rack are in agreement with the theoretical values given by angular decomposition. These results serve to assess the compliance with biological criteria to avoid impingement risks and guide fish towards a bypass.

ABSTRACT IMPACTS OF LAND COVER AND CLIMATE CHANGE ON WATER RESOURCES IN SUASCO RIVER WATERSHED September 2015 AMMARA TALIB, BS., PUNJAB UNIVERSITY LAHORE MS., UNIVERSITY OF MASSACHUSETTS AMHERST Directed by: Professor Tim Randhir Hydrological balance and biogeochemical processes in watershed are significantly influenced by changes in land use land cover (LULC) and climate change. Those changes can influence interception, evapotranspiration (ET), infiltration, soil moisture, water balance and biogeochemical cycling of carbon, nitrogen and other elements at regional to global scales. The impacts of these hydrological disturbances are generally reflected in form of increasing runoff rate and volume, more intense and frequent floods, decreasing groundwater recharge and base flow, elevated levels of sediments and increase in concentration of nutrients in both streams and shallow groundwater. Water quality of Sudbury, Assabet and Concord (SuAsCo) watershed in Massachusetts is also compromised because of influx of runoff, sediments and nutrients. There is a crucial need to evaluate the synergistic effects of LULC change and climate change on the water quality and water quantity in a watershed system. A watershed simulation model is used to simulate hydrologic processes and water quality changes in sediment loads, total nitrogen (TN), and total phosphorus (TP). The model is calibrated and validated with field-measured data. Climatic scenarios are represented by downscaled regional projections from Global Climate Model (GCM) models and regional built out scenarios of LULC are used to assess the impacts of projected LULC and climate change on water quality and water quantity. Simultaneous changes in LULC and climate significantly affect the water resources in the SuAsCo River watershed. Change in climate increased ET (4.7 %) because of high temperature, but independent change in land cover reduced ET (6.5%) because of less available vegetation. Combined change in land cover and climate reduced ET (2.1%) overall, which indicates that land cover change has significant impact on ET. Change in climate increased total run off (6%) and this increase is more significant as compared to 2.7 % increase in total runoff caused by land cover change. Change in land cover increased surface runoff more significantly (69.2%) than 7.9 % increase caused by climate change. Combined change in land cover and climate further increased the average storm peak volume (12.8 percent) because of high precipitation and impervious area in future. There is a potential for reducing runoff, sediments and nutrients loads by using conservation policies and adaptation strategies. This research provides valuable information about the dynamics of watershed system, as well as the complex processes that impair water resources.

Alcoholism and alcohol abuse represent a significant medical and societal problem, and have been thoroughly investigated in humans as well as using animal models. A less well understood aspect of alcohol related disorders is the possible effect of this drug on offspring whose parents were exposed prior to conception. The zebrafish has been successfully employed in alcohol research, however, the effect of exposing the parents to alcohol before fertilization of the eggs on offspring has not been demonstrated in this species. In this proof of concept study, we attempt to address this hiatus. We exposed both adult male and female zebrafish to 0.0% (control) or 0.5% (vol/vol) alcohol chronically for 7 days, subsequently bred the fish within their respective treatment group, collected the fertilized eggs, allowed them to develop, and tested the behavior of free-swimming offspring at their age of 7-9 days post-fertilization. We conducted the analysis in two genetically distinct quasi-inbred strains of zebrafish, AB and TL. Although gross morphology and general activity of the fish appeared unaffected, we found significant behavioral alterations in offspring of alcohol exposed parents compared to offspring of control parents in both strains. These alterations included robustly increased duration and reduced frequency of immobility, increased turn angle, and increased intra-individual variance of turn angle in offspring of alcohol exposed parents in both strains. The mechanisms underlying these behavioral effects or whether the effects are due to exposure of the father, the mother, or both to alcohol are unknown. Nevertheless, our results now set the stage for future studies with zebrafish that will address these questions.

It is recognized that orbital forcing of the ice sheet is through the summer air temperature, which however covaries with the sea surface temperature and both precede the ice volume signal, suggesting the ocean as an intermediary of the glacial cycles. To elucidate the ocean role, I present here a minimal box model, which entails two key physics overlooked by most climate models. First, I discern a robust ‘convective’ bound on the ocean cooling in a coupled ocean/atmosphere, and second, because of their inherent turbulence, I posit that the climate is a macroscopic manifestation of a nonequilibrium thermodynamic system. As their deductive outcome, the ocean entails bistable equilibria of maximum entropy production, which would translate to bistable ice states of polar cap and Laurentide ice sheet, enabling large ice-volume signal when subjected to modulated forcing. Since the bistable interval is lowered during Pleistocene cooling, I show that its interplay with the ice–albedo feedback may account for the mid-Pleistocene transition from 41-ky obliquity cycles to 100-ky ice-age cycles paced by eccentricity. Observational tests of the theory and its parsimony in resolving myriad glacial puzzles suggest that the theory has captured the governing physics of the Pleistocene glacial cycles.

Coastal communities in the Coral Triangle are increasingly threatened by climate change. Sea-level rise (SLR) will result in biophysical and socioeconomic impacts that could increase the loss of livelihoods, cultural heritage and infrastructure. Effective adaptation requires a holistic approach that incorporates scientific knowledge together with local and traditional knowledge. Community-based adaptation built on local knowledge is of great value for environmental management, particularly when scientific data are lacking. This article reports a case study that integrated traditional and scientific knowledge using participatory three-dimensional modeling (P3DM) in BoeBoe village, Solomon Islands. P3DM is a process by which members of the local community build a physical terrain model and overlay it with the location of important resources such as protected areas or harvesting sites. Additionally, SLR inundation scenarios based on surveyed elevations were incorporated into a geographic information system (GIS), allowing for a real-time integration of science with local knowledge. Despite discrepancies in scales and accuracy, information from both the P3DM and GIS were complementary. The process, itself, provided a forum for discussion between many members of the village who would normally not be involved and highlighted the importance of community engagement when building capacity for adaptation to climate change.