scholarly journals Oxygen Consumption Rates of Sponges and the Effect of UV-B Radiation and Sediment

2021 ◽  
Author(s):  
◽  
Heather Joanne Rose Murray
Keyword(s):  
Oxygen Consumption ◽  
Environmental Stress ◽  
Global Climate ◽  
Ultraviolet B ◽  
Specific Level ◽  
Physiological Processes ◽  
Consumption Rates ◽  
Species Specific ◽  
Benthic Ecosystems ◽  
The Impact

<p>Sponges are an important part of many benthic ecosystems, but little is known of their physiology and ecology, which is alarming given the predicted rise in global environmental stress and observed increases in mortality and disease of these organisms. The overall aim of this study was to further understand the physiological processes of sponges and the influence of environmental stress on these organisms. Oxygen consumption rates were investigated, as this is an important measure of the energy required for all physiological activities. The impact of ultraviolet-B(UV-B) radiation and sedimentation on sponges were selected because their input into the marine environment has been predicted to increase in the future, yet little is known about their affect on these organisms. Oxygen consumption rates were measured from a number of temperate and tropical sponges in New Zealand and Indonesia. Variability in oxygen consumption rates was found within and between species from their respective habitats. Interestingly, oxygen consumption rates in the temperate sponges appeared to increase with the proportion of inorganic material (spicule load). Ultraviolet-B radiation, at 60microWcm-2, was found to have no affect on the oxygen consumption of model temperate and tropical sponges. Sponge oxygen consumption, however, increased with repetitive exposure to 2.5 g L-1of sediment, while rates decreased in specimens under higher levels at 8.5 and 16.5 g L-1. Explanations for differences in oxygen consumption rates were constrained by the low level of information on sponges at a species-specific level, and highlighted the needed for future bioenergetic research. The results from the UV-B and sedimentation work suggest that some sponge species may be able to tolerate increasing environmental stress with the onset of global climate change, although interactions between factors could have the potential to negatively affect these organisms.</p>

scholarly journals Oxygen Consumption Rates of Sponges and the Effect of UV-B Radiation and Sediment

2021 ◽  
Author(s):  
◽  
Heather Joanne Rose Murray
Keyword(s):  
Oxygen Consumption ◽  
Environmental Stress ◽  
Global Climate ◽  
Ultraviolet B ◽  
Specific Level ◽  
Physiological Processes ◽  
Consumption Rates ◽  
Species Specific ◽  
Benthic Ecosystems ◽  
The Impact

<p>Sponges are an important part of many benthic ecosystems, but little is known of their physiology and ecology, which is alarming given the predicted rise in global environmental stress and observed increases in mortality and disease of these organisms. The overall aim of this study was to further understand the physiological processes of sponges and the influence of environmental stress on these organisms. Oxygen consumption rates were investigated, as this is an important measure of the energy required for all physiological activities. The impact of ultraviolet-B(UV-B) radiation and sedimentation on sponges were selected because their input into the marine environment has been predicted to increase in the future, yet little is known about their affect on these organisms. Oxygen consumption rates were measured from a number of temperate and tropical sponges in New Zealand and Indonesia. Variability in oxygen consumption rates was found within and between species from their respective habitats. Interestingly, oxygen consumption rates in the temperate sponges appeared to increase with the proportion of inorganic material (spicule load). Ultraviolet-B radiation, at 60microWcm-2, was found to have no affect on the oxygen consumption of model temperate and tropical sponges. Sponge oxygen consumption, however, increased with repetitive exposure to 2.5 g L-1of sediment, while rates decreased in specimens under higher levels at 8.5 and 16.5 g L-1. Explanations for differences in oxygen consumption rates were constrained by the low level of information on sponges at a species-specific level, and highlighted the needed for future bioenergetic research. The results from the UV-B and sedimentation work suggest that some sponge species may be able to tolerate increasing environmental stress with the onset of global climate change, although interactions between factors could have the potential to negatively affect these organisms.</p>

scholarly journals Species-specific impacts of suspended sediments on gill structure and function in coral reef fishes

2017 ◽  
Vol 284 (1866) ◽  
pp. 20171279 ◽  
Author(s):  
Sybille Hess ◽  
Leteisha J. Prescott ◽  
Andrew S. Hoey ◽  
Shannon A. McMahon ◽  
Amelia S. Wenger ◽  
...  
Keyword(s):  
Oxygen Consumption ◽  
Suspended Sediment ◽  
Suspended Sediments ◽  
Reef Fishes ◽  
Consumption Rates ◽  
Gill Structure ◽  
Mechanistic Basis ◽  
Metabolic Performance ◽  
Species Specific ◽  
Sediment Exposure

Reduced water quality, in particular increases in suspended sediments, has been linked to declines in fish abundance on coral reefs. Changes in gill structure induced by suspended sediments have been hypothesized to impair gill function and may provide a mechanistic basis for the observed declines; yet, evidence for this is lacking. We exposed juveniles of three reef fish species ( Amphiprion melanopus , Amphiprion percula and Acanthochromis polyacanthus ) to suspended sediments (0–180 mg l −1 ) for 7 days and examined changes in gill structure and metabolic performance (i.e. oxygen consumption). Exposure to suspended sediments led to shorter gill lamellae in A. melanopus and A. polyacanthus and reduced oxygen diffusion distances in all three species. While A. melanopus exhibited impaired oxygen uptake after suspended sediment exposure, i.e. decreased maximum and increased resting oxygen consumption rates resulting in decreased aerobic scope, the oxygen consumption rates of the other two species remained unaffected. These findings imply that species sensitive to changes in gill structure such as A. melanopus may decline in abundance as reefs become more turbid, whereas species that are able to maintain metabolic performance despite suspended sediment exposure, such as A. polyacanthus or A. percula , may be able to persist or gain a competitive advantage.

scholarly journals Looking Back to Move Forward: Lessons From Three Decades of Research and Management of Cetacean Tourism in New Zealand

2021 ◽  
Vol 8 ◽  
Author(s):  
Maddalena Fumagalli ◽  
Marta Guerra ◽  
Tom Brough ◽  
William Carome ◽  
Rochelle Constantine ◽  
...  
Keyword(s):  
New Zealand ◽  
Local Community ◽  
Global Climate ◽  
Management Strategies ◽  
Scientific Practices ◽  
Anthropogenic Stressor ◽  
Challenges And Opportunities ◽  
Management Approaches ◽  
Species Specific ◽  
The Impact

Cetacean tourism in Aotearoa New Zealand is now over 30 years old and has experienced substantial growth in visitor numbers and operations. The industry is remarkably diverse, targeting several dolphin and whale species, and encompassing varied habitats in coastal waters, fiords and submarine canyons. The knowledge and experience collected over these past 30 years has both advanced the global understanding of cetacean tourism, and influenced scientific practices for its study and management. Here we review the approaches taken in quantifying the impact of cetacean tourism in New Zealand, and critically assess the efficacy of the research and management strategies adopted. We place particular focus on the Bay of Islands, Hauraki Gulf, Kaikoura, Akaroa and Fiordland, areas that include the oldest, and longest studied industries nationally. We propose a set of best research practices, expose the most notable knowledge gaps and identify emerging research questions. Drawing on perspectives from the natural and social sciences, we outline the key determinants of failure and success in protecting cetacean populations from the detrimental impact of tourism. We suggest four golden rules for future management efforts: (1) acknowledge cetacean tourism as a sub-lethal anthropogenic stressor to be managed with precaution, (2) apply integrated and adaptive site- and species-specific approaches, (3) fully conceptualize tourism within its broader social and ecological contexts, and (4) establish authentic collaborations and engagement with the local community. Lastly, we forecast upcoming challenges and opportunities for research and management of this industry in the context of global climate change. Despite New Zealand's early establishment of precautionary legislation and advanced tourism research and management approaches, we detected flaws in current schemes, and emphasize the need for more adaptive and comprehensive strategies. Cetacean tourism remains an ongoing challenge in New Zealand and globally.

scholarly journals Transcriptomics Integrated With Metabolomics Reveal the Effects of Ultraviolet-B Radiation on Flavonoid Biosynthesis in Antarctic Moss

2021 ◽  
Vol 12 ◽  
Author(s):  
Shenghao Liu ◽  
Shuo Fang ◽  
Chenlin Liu ◽  
Linlin Zhao ◽  
Bailin Cong ◽  
...  
Keyword(s):  
Dna Repair ◽  
Signaling Pathway ◽  
Global Climate ◽  
Flavonoid Biosynthesis ◽  
Ultraviolet B ◽  
Repair System ◽  
Ros Scavenging ◽  
The Antarctic ◽  
The Impact ◽  
Antarctic Moss

Bryophytes are the dominant vegetation in the Antarctic continent. They have suffered more unpleasant ultraviolet radiation due to the Antarctic ozone layer destruction. However, it remains unclear about the molecular mechanism of Antarctic moss acclimation to UV-B light. Here, the transcriptomics and metabolomics approaches were conducted to uncover transcriptional and metabolic profiling of the Antarctic moss Leptobryum pyriforme under UV-B radiation. Totally, 67,290 unigenes with N50 length of 2,055 bp were assembled. Of them, 1,594 unigenes were significantly up-regulated and 3353 unigenes were markedly down-regulated under UV-B radiation. These differentially expressed genes (DEGs) involved in UV-B signaling, flavonoid biosynthesis, ROS scavenging, and DNA repair. In addition, a total of 531 metabolites were detected, while flavonoids and anthocyanins accounted for 10.36% of the total compounds. There were 49 upregulated metabolites and 41 downregulated metabolites under UV-B radiation. Flavonoids were the most significantly changed metabolites. qPCR analysis showed that UVR8-COP1-HY5 signaling pathway genes and photolyase genes (i.e., LpUVR3, LpPHR1, and LpDPL) were significantly up-regulated under UV-B light. In addition, the expression levels of JA signaling pathway-related genes (i.e., OPR and JAZ) and flavonoid biosynthesis-related genes were also significantly increased under UV-B radiation. The integrative data analysis showed that UVR8-mediated signaling, jasmonate signaling, flavonoid biosynthesis pathway and DNA repair system might contribute to L. pyriforme acclimating to UV-B radiation. Therefore, these findings present a novel knowledge for understanding the adaption of Antarctic moss to polar environments and provide a foundation for assessing the impact of global climate change on Antarctic land plants.

1033 REDUCING NITROGEN FERTILIZER APPLICATIONS BY BALANCING THE NITROGEN SULFUR RATIO

HortScience ◽  
1994 ◽  
Vol 29 (5) ◽  
pp. 576d-576
Author(s):  
Ellen T. Paparozzi
Keyword(s):  
Groundwater Contamination ◽  
Nitrogen Fertilizer ◽  
Nutrient Balance ◽  
Ornamental Plants ◽  
Consumer Perceptions ◽  
Consumer Acceptance ◽  
Statistical Techniques ◽  
Physiological Processes ◽  
The Impact ◽  
Future Plans

Fertilizer particularly nitrogen is part of the concern about groundwater contamination. Many floricultural and ornamental plants do not need the high rates of nitrogen that are typically recommended. However, whenever one alters the quantity of a given nutrient the overall nutrient balance, as well as other physiological processes, changes. A brief overview of our research on poinsettias, roses, and chrysanthemums will be presented. Suggested ratios, critical S levels and nutrient problems associated with incorrect balances will be shared. Limitations due to statistical methods and the impact nutrient balance has on certain plant processes such as flowering and coloring and thus, consumer acceptance will be summarized. Future plans in this area may focus on the need for new statistical techniques, nutrient acquisition by roots and consumer perceptions of plant quality.

Impact of LULC Changes on LST in Rajshahi District of Bangladesh: A Remote Sensing Approach

2020 ◽  
Vol 3 (1) ◽  
pp. 11-23 ◽  
Author(s):  
Abdulla Al Kafy ◽  
Abdullah Al-Faisal ◽  
Mohammad Mahmudul Hasan ◽  
Md. Soumik Sikdar ◽  
Mohammad Hasib Hasan Khan ◽  
...  
Keyword(s):  
Remote Sensing ◽  
Surface Temperature ◽  
Land Surface ◽  
Agricultural Land ◽  
Global Climate ◽  
Urban Expansion ◽  
Water Bodies ◽  
Landsat 8 ◽  
Lulc Changes ◽  
The Impact

Urbanization has been contributing more in global climate warming, with more than 50% of the population living in cities. Rapid population growth and change in land use / land cover (LULC) are closely linked. The transformation of LULC due to rapid urban expansion significantly affects the functions of biodiversity and ecosystems, as well as local and regional climates. Improper planning and uncontrolled management of LULC changes profoundly contribute to the rise of urban land surface temperature (LST). This study evaluates the impact of LULC changes on LST for 1997, 2007 and 2017 in the Rajshahi district (Bangladesh) using multi-temporal and multi-spectral Landsat 8 OLI and Landsat 5 TM satellite data sets. The analysis of LULC changes exposed a remarkable increase in the built-up areas and a significant decrease in the vegetation and agricultural land. The built-up area was increased almost double in last 20 years in the study area. The distribution of changes in LST shows that built-up areas recorded the highest temperature followed by bare land, vegetation and agricultural land and water bodies. The LULC-LST profiles also revealed the highest temperature in built-up areas and the lowest temperature in water bodies. In the last 20 years, LST was increased about 13ºC. The study demonstrates decrease in vegetation cover and increase in non-evaporating surfaces with significantly increases the surface temperature in the study area. Remote-sensing techniques were found one of the suitable techniques for rapid analysis of urban expansions and to identify the impact of urbanization on LST.

The Impact of Environmental Stress on Cognitive Performance: A Systematic Review

2019 ◽  
Vol 61 (8) ◽  
pp. 1205-1246 ◽  
Author(s):  
Kristy Martin ◽  
Emily McLeod ◽  
Julien Périard ◽  
Ben Rattray ◽  
Richard Keegan ◽  
...  
Keyword(s):  
Systematic Review ◽  
Environmental Stress ◽  
Task Performance ◽  
Sea Level ◽  
Cognitive Performance ◽  
Cognitive Task ◽  
Individual Characteristics ◽  
Eligibility Criteria ◽  
Healthy Human ◽  
The Impact

Objective: In this review, we detail the impact of environmental stress on cognitive and military task performance and highlight any individual characteristics or interventions which may mitigate any negative effect. Background: Military personnel are often deployed in regions markedly different from their own, experiencing hot days, cold nights, and trips both above and below sea level. In spite of these stressors, high-level cognitive and operational performance must be maintained. Method: A systematic review of the electronic databases Medline (PubMed), EMBASE (Scopus), PsycINFO, and Web of Science was conducted from inception up to September 2018. Eligibility criteria included a healthy human cohort, an outcome of cognition or military task performance and assessment of an environmental condition. Results: The search returned 113,850 records, of which 124 were included in the systematic review. Thirty-one studies examined the impact of heat stress on cognition; 20 of cold stress; 59 of altitude exposure; and 18 of being below sea level. Conclusion: The severity and duration of exposure to the environmental stressor affects the degree to which cognitive performance can be impaired, as does the complexity of the cognitive task and the skill or familiarity of the individual performing the task. Application: Strategies to improve cognitive performance in extreme environmental conditions should focus on reducing the magnitude of the physiological and perceptual disturbance caused by the stressor. Strategies may include acclimatization and habituation, being well skilled on the task, and reducing sensations of thermal stress with approaches such as head and neck cooling.

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