scholarly journals Lagged recovery of fish spatial distributions following a cold-water perturbation

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
M. D. Robertson ◽  
J. Gao ◽  
P. M. Regular ◽  
M. J. Morgan ◽  
F. Zhang

AbstractAnomalous local temperature and extreme events (e.g. heat-waves) can cause rapid change and gradual recovery of local environmental conditions. However, few studies have tested whether species distribution can recover following returning environmental conditions. Here, we tested for change and recovery of the spatial distributions of two flatfish populations, American plaice (Hippoglossoides platessoides) and yellowtail flounder (Limanda ferruginea), in response to consecutive decreasing and increasing water temperature on the Grand Bank off Newfoundland, Canada from 1985 to 2018. Using a Vector Autoregressive Spatiotemporal model, we found the distributions of both species shifted southwards following a period when anomalous cold water covered the northern sections of the Grand Bank. After accounting for density-dependent effects, we observed that yellowtail flounder re-distributed northwards when water temperature returned and exceeded levels recorded before the cold period, while the spatial distribution of American plaice has not recovered. Our study demonstrates nonlinear effects of an environmental factor on species distribution, implying the possibility of irreversible (or hard-to-reverse) changes of species distribution following a rapid change and gradual recovery of environmental conditions.

2020 ◽  
Author(s):  
Javier Gutierrez Illan ◽  
Guiming Wang ◽  
Fred L Cunningham ◽  
Tommy D King

Abstract Background: Resource utilization strategies of avian migrants are a major concern for conservation and management. Consequently, the ability to predict potential shifts in migratory species distribution and migratory behaviour is a pressing challenge for predictive ecology under global changes. There are two main strategies of resource use adopted by migratory birds: niche tracking for similar environmental conditions and niche switching between different environmental conditions between seasons. Our objective was to examine whether the “niche tracker” or “niche switcher” hypothesis would better explain seasonal variations in the ecological niche breadth and overlap of the American White Pelicans (AWPE, Pelecanus erythrorhynchos). We also tested whether recent changes in the non-breeding ground land-use have altered the land-cover niche breadth of AWPE. Methods: We built Maximum Entropy Models (MAXENT) to predict the AWPE breeding and non-breeding ranges using GPS locations, climate variables, and land-cover variables. We then compared the estimated climatic and land-cover niche breadth and the overlap between the breeding and non-breeding grounds. Results: Our climate, land-cover, and combined species distribution models had a good to excellent predictive performance. Our findings supported the hypothesis that AWPE would be climatic niche switchers. American white pelicans showed little climatic niche overlap between nesting and wintering seasons. Migrants on the breeding grounds showed broader climatic niche than both residents and migrants on the non-breeding grounds. Finally, declines in availability of food resources provided by commercial aquaculture on the non-breeding grounds appeared to increase land-cover niche breadth.Conclusions: Climatic niche switching suggests that AWPE may adapt to future climate changes with unexpected spatial distributions under global change. Future declines in wetlands and food resources may restrict AWPE spatial distributions. Future studies need to investigate AWPE demographic consequences of climate and land-use changes.


Foods ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 1208
Author(s):  
Ewa Olechno ◽  
Anna Puścion-Jakubik ◽  
Małgorzata Elżbieta Zujko ◽  
Katarzyna Socha

Coffee brews are one of the most popular drinks. They are consumed for caffeine and its stimulant properties. The study aimed to summarize data on the influence of various factors on caffeine content in brews prepared with different methods. The study was carried out using a literature review from 2010–2020. PubMed and Google Scholar databases were searched. Data on caffeine content was collected by analyzing the following factors: the influence of species, brewing time, water temperature, pressure, degree of roast, grinding degree, water type, water/coffee ratio as well as other factors (such as geographical origin). To sum up, converting caffeine content to 1 L of the brew, the highest content is that of brews prepared in an espresso machine (portafilter), with the amount of 7.5 g of a coffee blend (95% Robusta + 5% Arabica), and water (the volume of coffee brew was 25 mL) at a temperature of 92 °C and a pressure of 7 bar, but the highest content in one portion was detected in a brew of 50 g of Robusta coffee poured with 500 mL of cold water (25 °C) and boiled.


Water ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 975
Author(s):  
Kaiji Suzuki ◽  
Nobuo Ishiyama ◽  
Itsuro Koizumi ◽  
Futoshi Nakamura

Clarifying the combined effects of water temperature and other environmental factors on the species distributions of cold-water fishes is the first step toward obtaining a better understanding of the complex impacts of climate warming on these species. In the present study, we examined the abundance and occurrence of the fluvial sculpin, Cottus nozawae, in response to water temperature along environmental gradients in northern Japan. The abundance survey was conducted in the Sorachi River catchment with two-pass electrofishing with a backpack electrofisher. For the occurrence survey, we carried out one-pass electrofishing in the Sorachi, Chitose, and Tokachi River catchments. Fish sampling was conducted once from July to August 2018 in the Sorachi River catchment, from May to June 2011 in the Chitose River catchment, and from July to September 2012 in the Tokachi River catchment. Generalized linear mixed models (GLMMs) and generalized linear models (GLMs) were used for the abundance and occurrence analyses, respectively. We found that the mean summer water temperature was the most influential factor on the distribution of C. nozawae; the abundance and occurrence were both negatively affected by increased water temperatures. In the occurrence model, occurrence probabilities of 0.9 and 0.5 for C. nozawae corresponded to mean summer temperatures of 12.0 and 16.1 °C, respectively. Furthermore, we identified a combined effect of water temperature and current velocity on the abundance of C. nozawae. The increased mean summer water temperature had a stronger negative effect on C. nozawae abundance under gentle flow conditions. While the precise mechanisms of this combined effect could not be determined in this study, stressors associated with low current velocities may increase their vulnerability to higher water temperatures. Our findings indicate that flow disturbances caused by human activities such as excessive water abstraction may exacerbate the negative impacts of climate warming on populations of C. nozawae in the future.


Author(s):  
Henglong Xu ◽  
Yong Jiang ◽  
Wei Zhang ◽  
Mingzhuang Zhu ◽  
Khaled A. S. Al-Rasheid ◽  
...  

The annual variations in body-size spectra of planktonic ciliate communities and their relationships to environmental conditions were studied based on a 12-month dataset (June 2007 to May 2008) from Jiaozhou Bay on the Yellow Sea coast of northern China. Based on the dataset, the body sizes of the ciliates, expressed as equivalent spherical diameters, included five ranks: S1 (5–35 μm); S2 (35–55 μm); S3 (55–75 μm); S4 (75–100 μm); and S5 (100–350 μm). These body-size ranks showed a clear temporal succession of dominance in the order of S2 (January–April) → S1 (May–July) → S4 (August–September) → S3 (October–December). Multivariate analyses showed that the temporal variations in their body-size patterns were significantly correlated with changes in environmental conditions, especially water temperature, salinity, dissolved oxygen concentration (DO) and nutrients. In terms of abundance, rank S2 was significantly correlated with water temperature, DO and nutrients, whereas ranks S4 and S5 were correlated with the salinity and nutrients respectively (P < 0.05). These results suggest that the body-size patterns of planktonic ciliate communities showed a clear temporal pattern during an annual cycle and significantly associated with environmental conditions in marine ecosystems.


2021 ◽  
Author(s):  
Manfred A. Lange

&lt;p&gt;The environmental conditions in urban settings are subject to processes and conditions within cities, on the one hand, and have a strong bearing on the overall conditions and the quality of life of the cities&amp;#8217; inhabitants, on the other. The built environment, in general, and buildings and infrastructure, in particular, play a major role in shaping the urban environment. At the same time, environmental conditions affect strongly the conditions within and outside of buildings.&lt;/p&gt;&lt;p&gt;The continued growth of cities in the Eastern Mediterranean and Middle Eastern (EMME) region, the demise of environmental quality adds to the challenges faced by their inhabitants. Of the many factors contributing to these threats, climate change and its amplification in urban structures, the increasing load of pollutants in air and water and the rising numbers of dust storms as well as the growing amount of solid and liquid waste stand out.&lt;/p&gt;&lt;p&gt;The significant increase in the number of cars and the rising quantity of energy production has contributed to ever-worsening air quality in EMME cities. More specifically, urban road transport represents one of the major sources of air-borne pollutants in many of these cities and causes substantial threats to the health of their inhabitants.&lt;/p&gt;&lt;p&gt;The Middle East and North Africa (MENA) and the EMME region are major sources of desert dust storms that travel north and east to Europe and Asia, thereby strongly affecting cities and their air quality in the EMME. Dust storms and suspended bacteria and viruses pose serious consequences to communities in the EMME region and are likely to worsen due to ongoing climate change.&lt;/p&gt;&lt;p&gt;Present and future changes in climate conditions will have numerous adverse effects on the EMME region, in general, and on EMME cities, in particular. This includes extended heat waves as well as enhanced water scarcity for inhabitants and green spaces. In combination with poor air quality, this will cause severe health risks for urban populations as well as the need for increased and extended periods of space cooling in private, commercial and municipal buildings. The greater needs for water and energy in urban structures are interrelated and have been described by the Water-Energy Nexus. The higher demand for water is increasingly satisfied through desalination, which is particularly energy-intensive. The need for additional space cooling during hot spells in cities will require more electricity.&lt;/p&gt;&lt;p&gt;The high rate of population growth, ever-increasing urbanization, changes in lifestyles and economic expansion in the EMME countries result in steadily increasing volumes of solid and liquid waste. The waste problems are exacerbated by the rising number of displaced persons and refugees in growing camps in some of the EMME countries, particularly, in Turkey, Jordan and Lebanon. The huge quantity of daily produced sewage sludge in Middle Eastern countries presents a serious challenge due to its high treatment costs and risks to the environment and human health.&lt;/p&gt;&lt;p&gt;This paper will address some of these challenges, which call for holistic and interdisciplinary efforts to design effective and sustainable adaptation strategies in EMME cities.&lt;/p&gt;


2018 ◽  
Vol 44 ◽  
pp. 00017 ◽  
Author(s):  
Agnieszka Chmielewska

The article discusses the influence of the cold water temperature on the amount of energy consumed for the purposes of the DHW preparation in multi-family buildings. The article begins with a presentation of the DHW consumption readings from a multi-family building, recorded on a monthly basis during the period of 4 years. The readings constituted the base for calculating the demand for energy for the purposes of the DHW preparation. Subsequently, basing on the output water temperature readings from the water treatment plant, it was proved that the temperature of the mains water fluctuates throughout the year. The review of the available literature, as well as the measurements, confirmed that it is necessary to develop a new model of the cold water temperature that would take into account the type of intake in a water treatment plant. The final part of the article presents how the accepted assumptions about the temperature of the mains water influence the consumption of energy for the purposes of the DHW preparation.


1975 ◽  
Vol 39 (1) ◽  
pp. 93-102 ◽  
Author(s):  
R. M. Smith ◽  
J. M. Hanna

Fourteen male subjects with unweighted mean skinfolds (MSF) of 10.23 mm underwent several 3-h exposures to cold water and air of similar velocities in order to compare by indirect calorimetry the rate of heat loss in water and air. Measurements of heat loss (excluding the head) at each air temperature (Ta = 25, 20, 10 degrees C) and water temperature (Tw = 29–33 degrees C) were used in a linear approximation of overall heat transfer from body core (Tre) to air or water. We found the lower critical air and water temperatures to fall as a negative linear function of MSF. The slope of these lines was not significantly different in air and water with a mean of minus 0.237 degrees C/mm MSF. Overall heat conductance was 3.34 times greater in water. However, this value was not fixed but varied as an inverse curvilinear function of MSF. Thus, equivalent water-air temperatures also varied as a function of MSF. Between limits of 100–250% of resting heat loss the followingrelationships between MSF and equivalent water-air temperatures were found (see article).


2020 ◽  
pp. 227-238
Author(s):  
Brian Helmuth

Ectothermic organisms experience their local environments in ways that humans can have difficulty conceptualizing. Physics-based (ecomechanical) approaches, for example heat budget models, can lend insights into how an organism’s very local environmental conditions (microclimate) can drive niche-level conditions such as body temperature; these in turn drive physiological processes. Quantitative methods also allow insights into the temporal and spatial scales that may ultimately determine responses to larger-scale environmental change. For example, for small, sessile organisms, microhabitats such as crevices in rocks may provide microrefugia that allow survival during heat waves. As a result, larger-scale recovery following heat waves (rescue effects) may ultimately be influenced by much smaller-scale processes. Ecomechanics techniques also facilitate the use of interventions such as shading that can maintain environmental conditions within physiological tolerance levels.


PeerJ ◽  
2019 ◽  
Vol 7 ◽  
pp. e7927 ◽  
Author(s):  
Juan C. Levesque

Oceanic environmental conditions influence, shape, and control the geographical range, spatial distribution, abundance, and size composition of marine fauna. Water temperature, salinity, dissolved oxygen, depth, and sediment type influence select fish life-history characteristics and community structure. Marine communities are vulnerable to major changes in environmental conditions, but the response and severity depends on various biological or ecological factors, such as resilience to stress or adaptation. Researchers around the world have predicted and documented numerous alterations in fish communities caused by ongoing significant physicochemical shifts associated with natural and potentially unnatural sources, but published studies describing the historical conditions are lacking for most regions around the world, including the coastal waters off New Jersey. Given the need to understand these processes, a multifaceted investigation was undertaken to describe, evaluate, and compare the oceanic conditions and nearshore marine fauna community off New Jersey during 1988 through 2015. Findings showed the oceanic conditions varied over time and space. Mean surface water temperature increased significantly about 0.6 °C per decade, mean salinity decreased about 1.3 psu per decade, and dissolved oxygen increased 0.09 mg/l per decade. Over 20.4 million fish and invertebrates (1,338.3 mt) representing 214 (water temperature preference classified) species (not including unidentified species) were collected within 15 strata (areas: 12−26) off the coast of New Jersey from 1988 to 2015. Three marine fauna water temperature preference groups (coldwater-adapted, warmwater-adapted, and subtropic-adapted) were identified in the study area. The main coldwater-adapted species collected were longfin squid (Loligo pealei) (n = 2, 225, 975), Atlantic herring (Clupea harengus) (n = 544, 032), and little skate (Leucoraja erinacea) (n = 316, 356), while Atlantic butterfish (Peprilus triacanthus) (n = 2, 873, 138), scup (Stenotomus chrysops) (n = 1, 318, 569), and northern searobin (Prionotus carolinus) (n = 503, 230) represented the warmwater-adapted group. Bay anchovy (Anchoa mitchilli) (n = 9, 227, 960), striped anchovy (Anchoa hepsetus) (n = 245, 214), and Atlantic moonfish (Vomer setapinnis) (n = 38, 691) denoted the subtropic-adapted group. Subtropic-adapted species were the most abundant and coldwater-adapted were the least abundant water temperature preference group. The estimated abundance of coldwater-adapted species declined, warmwater-adapted species slightly increased, and subtropic-adapted species decreased with time, which suggest the environmental conditions are influencing and thereby shifting the marine community.


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