scholarly journals Drastic effects of climate change on Mediterranean marine forests

2018 ◽  
Author(s):  
Jana Verdura ◽  
Alba Vergés ◽  
Jorge Santamaría ◽  
Sònia de Caralt ◽  
Enric Ballesteros ◽  
...  
Keyword(s):  
Climate Change ◽  
High Temperature ◽  
Shallow Water ◽  
High Temperatures ◽  
Size Structure ◽  
Habitat Destruction ◽  
Rocky Shores ◽  
Relict Population ◽  
Summer Temperatures ◽  
Rocky Bottoms

Macroalgal forests have gone missing in several temperate rocky shores during the last decades, triggering important changes in the seascape. Cystoseira species are some of the main habitat-forming species on shallow water Mediterranean rocky bottoms and follow the same tendency, which has been mainly related to habitat destruction and pollution. Here we suggest that abnormal positive thermal events may have contributed to this widespread Cystoseira decline. Densities and size structure distribution of C. crinita showed a drastic decline on a relict population coinciding with abnormal high summer temperatures. Additionally, we experimentally tested in the laboratory the cause-effect of high temperatures and UV radiation on C. crinita populations. Although, C. crinita was able to resist punctual high temperature peaks, exceptional and maintained periods of high temperatures (28ºC) lead to the death of all individuals, compromising the viability of these populations. Thus, climate change may seriously compromise C. crinita stands and act synergically with historical drivers of macroalgal decline such as pollution, habitat destruction and increased herbivorism.

scholarly journals Drastic effects of climate change on Mediterranean marine forests

2018 ◽  
Author(s):  
Jana Verdura ◽  
Alba Vergés ◽  
Jorge Santamaría ◽  
Sònia de Caralt ◽  
Enric Ballesteros ◽  
...  
Keyword(s):  
Climate Change ◽  
High Temperature ◽  
Shallow Water ◽  
High Temperatures ◽  
Size Structure ◽  
Habitat Destruction ◽  
Rocky Shores ◽  
Relict Population ◽  
Summer Temperatures ◽  
Rocky Bottoms

Macroalgal forests have gone missing in several temperate rocky shores during the last decades, triggering important changes in the seascape. Cystoseira species are some of the main habitat-forming species on shallow water Mediterranean rocky bottoms and follow the same tendency, which has been mainly related to habitat destruction and pollution. Here we suggest that abnormal positive thermal events may have contributed to this widespread Cystoseira decline. Densities and size structure distribution of C. crinita showed a drastic decline on a relict population coinciding with abnormal high summer temperatures. Additionally, we experimentally tested in the laboratory the cause-effect of high temperatures and UV radiation on C. crinita populations. Although, C. crinita was able to resist punctual high temperature peaks, exceptional and maintained periods of high temperatures (28ºC) lead to the death of all individuals, compromising the viability of these populations. Thus, climate change may seriously compromise C. crinita stands and act synergically with historical drivers of macroalgal decline such as pollution, habitat destruction and increased herbivorism.

scholarly journals Drastic effects of Climate Change on Mediterranean marine forests

2018 ◽  
Author(s):  
Jana Verdura ◽  
Alba Vergés ◽  
Jorge Santamaría ◽  
Sònia de Caralt ◽  
Enric Ballesteros ◽  
...  
Keyword(s):  
Climate Change ◽  
Natural Populations ◽  
Biodiversity Loss ◽  
Habitat Destruction ◽  
Rocky Shores ◽  
Fellowship Program ◽  
Summer Period ◽  
Marine Habitat ◽  
Radiation Conditions ◽  
Rocky Bottoms

Macroalgal forests have gone missing from most temperate rocky shores during the last decades, triggering an important biodiversity loss. Cystoseira species are some of the main marine habitat-forming species on shallow water Mediterranean rocky bottoms and follow the same tendency, mainly related to habitat destruction and pollution. However, here we suggest that anormal positive thermal events may contribute to this widespread Cystoseira decline. Monitoring thorough natural populations showed a drastic decline on a natural and relict C. crinita population in terms of density and structure coinciding with anormal high temperatures experienced during a summer period. Additionally, we experimentally test in the laboratory the cause-effect of those temperatures and UV radiation conditions experienced in the field on C. crinita populations. Although, C. crinita is able to resist high temperature picks, usually reached in Mediterranean summers, exceptional and maintained periods as those experienced during extreme events (28ºC) lead to the death of all individuals, compromising the viability and conservation of these forest-forming populations. We show how climate change may seriously compromise algal populations and synergically act with historical drivers of macroalgal decline (pollution, habitat destruction and herbivorism). Financial support from EU2020 (R+I) under grant agreement No 689518 (MERCES), MINECO (CGL2016-76341-R) and from University of Girona under congress assistance fellowship program for PhD and master students.

scholarly journals Effects of Multi-Scale Climate Change on The Distribution of Invasive Insect Populations and The Development of Ecological Services: A Case Study of Zeugodacus Cucurbitae (Coquillett)

2021 ◽  
Author(s):  
Yuyang Lian ◽  
Aqiang Wang ◽  
Bei Zeng ◽  
Heming Yang ◽  
Jinlei Li ◽  
...  
Keyword(s):  
Climate Change ◽  
High Temperature ◽  
High Temperatures ◽  
Population Distribution ◽  
Sub Saharan Africa ◽  
Distribution Area ◽  
Small Scale ◽  
Distribution Analysis ◽  
Short Term ◽  
Multi Scale

Abstract In order to clarify the effects of multi-scale climate change on the population distribution and ecological service function of Z.cucurbitae, this paper analyzed its suitable distribution area Z.cucurbitae in a wide scale using the MaxEnt ecological model. Z.cucurbitae were exposed under short-term high temperatures of 33°C, 37°C, 41°C and 45°C for 1h, which were set based on recorded high temperatures in the field. The effects of these temperatures on development and reproduction of Z.cucurbitae in successive three generations were evaluated. The results showed that under current climatic conditions, the suitable regions of Z.cucurbitae included most of South America, southeast North America, sub-Saharan Africa, part of Oceania and southern coastal areas of Asia. Under two carbon emissions scenarios (RCP4.5 and RCP8.5), the suitable area of Z.cucurbitae will expand compared to that under current environment and this expansion will generally be northwards. Short-term high temperature was not conducive to the development and reproduction of Z.cucurbitae. The F1 Z.cucurbitae exposed under 45°C for 1h stimulated its oviposition, and the offspring can still continue the population. When the offspring were continuously exposed to short-term high temperature until the F3, they could not oviposit. In the context of climate change, both large-scale and small-scale changes will affect the distribution and population breeding of Z.cucurbitae, which will lead to local sudden outbreak or migration disaster. Therefore, a broad-scale distribution analysis of all populations as a whole will result in a narrow ecological niche and may fail to predict the effects of some local small-scale habitat changes.

scholarly journals The unusual biology of marine file snakes with a perspective for the conservation of Acrochordus granulatus

2021 ◽  
Vol 14 (2) ◽  
Keyword(s):  
Climate Change ◽  
Shallow Water ◽  
The Philippines ◽  
Habitat Destruction ◽  
Oxygen Storage ◽  
Anthropogenic Factors ◽  
Marine Environments ◽  
Coastal Environments ◽  
Coastal Habitats ◽  
Distinct Evolutionary Lineage

Biodiversity and the function of tropical shallow-water marine environments are threatened by numerous anthropogenic factors, especially climate change, overharvesting of resources, and destruction of habitat. Marine snakes are important components of coastal shallow-water systems and should be considered as indicators of the health of coastal ecosystems such as mangroves. Acrochordid snakes (Acrochordidae: Acrochordus) represent a highly distinct evolutionary lineage with unusual adaptations to shallow water habitats and importance to biodiversity of tropical coastal regions. One of three congeneric species, Acrochordus granulatus (file snake), is an interesting and common inhabitant of coastal estuaries and mangroves in the Philippines. This paper reviews unusual attributes of A. granulatus and provides a perspective for its conservation in coastal habitats. Morphological, physiological, and behavioral characters of this snake are specialized for life in shallow-water marine environments such as mangroves. Unusual and specialized features confer abilities for prolonged submergence and include low metabolic rate, large capacity for oxygen storage, cutaneous gas exchange, nearly complete utilization of oxygen stores during aerobic submergence, intracardiac and cutaneous shunts for regulating blood flow, and reclusive behavior. Fresh water is required for water balance, and file snakes are dependent on rainfall in many habitats where they drink from freshwater lenses formed by precipitation on the surfaces of marine water. File snakes feed largely on fishes and are candidates as bio-indicators of the health of shallow-water coastal habitats. Attention should be given to threatening insults on coastal environments including climate change, habitat destruction, harvesting of resources, and other factors in need of research, monitoring, and plans for abatement. Importantly, conservation can be promoted by educating people about the docile behavior, unusual traits, and interesting ecology of A. granulatus. KEYWORDS: mangrove, shallow water, Acrochordidae, little file snake, conservation physiology, ecophysiology

scholarly journals Perceptions of workplace heat exposure and adaption behaviors among Chinese construction workers in the context of climate change

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Shu-Rong Han ◽  
Mingru Wei ◽  
Zhifeng Wu ◽  
Shanshan Duan ◽  
Xiangzhe Chen ◽  
...  
Keyword(s):  
Climate Change ◽  
High Temperature ◽  
High Temperatures ◽  
Heat Exposure ◽  
Construction Workers ◽  
Work Efficiency ◽  
Snowball Sampling ◽  
Online Questionnaire ◽  
Cross Sectional ◽  
The Impact

Abstract Background Workplace heat exposure can cause a series of heat-related illnesses and injuries. Protecting workers especially those undertake work outdoors from the risk of heat strain is a great challenge for many workplaces in China under the context of climate change. The aim of this study is to investigate the perceptions and adaptation behaviors of heat exposure among construction workers and to provide evidence for the development of targeted heat adaptation strategies nationally and internationally. Methods In 2020, we conducted a cross-sectional online questionnaire survey via WeChat Survey Star in China, using a purposive snowball sampling approach. A total of 326 construction workers submitted completed questionnaires. The perceptions of workplace heat exposure were measured using seven indicators: concerns over high temperature, perception of high temperature injury, attitudes towards both heat-related training and regulations, adjustment of working habits during heat, heat prevention measures in the workplace, and reduction of work efficiency. Bivariate and multivariate regression analyses were used to identify the factors significantly associated with workers’ heat perceptions and behavioral responses. Results 33.3% of the respondents were moderately or very concerned about heat exposure in the workplace. Less than half of the workers (43.8%) were worried about heat-related injuries. Workers who have either experienced work-related injuries (OR = 1.30, 95% CI 1.03–1.62) or witnessed injuries to others during high temperatures (OR = 1.12, 95% CI 1.02–1.27) were more concerned about heat exposure compared to other workers. Most respondents (63.5%) stated that their work efficiency declined during extremely hot weather. The factors significantly associated with a reduction of work efficiency included undertaking physically demanding jobs (OR = 1.28, 95% CI 1.07–1.54) and witnessing other workers’ injuries during high temperatures (OR = 1.26, 95% CI 1.11–1.43). More than half of the workers were willing to adjust their work habits to adapt to the impact of high temperatures (81.6%). The internet was the most common method to obtain heat prevention information (44.7%), and the most frequently used heat prevention measure was the provision of cool drinking water (64.8%). Conclusions Chinese construction workers lack heat risk awareness and are not well prepared for the likely increasing heat exposure in the workplace due to global warming. Therefore, there is a need to improve their awareness of heat-related injuries, strengthen high temperature related education and training, and update the current heat prevention policies to ensure compliance and implementation.

scholarly journals Female fruit flies cannot protect stored sperm from high temperature damage

2021 ◽  
Author(s):  
Benjamin S Walsh ◽  
Steven R Parratt ◽  
Rhonda R Snook ◽  
Amanda Bretman ◽  
David Atkinson ◽  
...  
Keyword(s):  
Climate Change ◽  
High Temperature ◽  
High Temperatures ◽  
Fruit Fly ◽  
High Temperature Stress ◽  
Population Persistence ◽  
Drosophila Virilis ◽  
Mature Sperm ◽  
Temperature Damage ◽  
The Impact

Recently, it has been demonstrated that heat-induced male sterility is likely to shape population persistence as climate change progresses. However, an under-explored possibility is that females may be able to successfully store and preserve sperm at temperatures that sterilise males, which could ameliorate the impact of male infertility on populations. Here, we test whether females from two fruit fly species can protect stored sperm from a high temperature stress. We find that sperm carried by female Drosophila virilis are almost completely sterilised by high temperatures, whereas sperm carried by female Zaprionus indianus show only slightly reduced fertility. Heat-shocked D. virilis females can recover fertility when allowed to remate, suggesting that the delivered heat-shock is destroying stored sperm and not directly damaging females in this species. The temperatures required to reduce fertility of mated females are substantially lower than the temperatures required to destroy mature sperm in males, suggesting that females are worse than males at protecting mature sperm. This suggests that female sperm storage is unlikely to ameliorate the impacts of high temperature fertility losses in males, and instead exacerbates fertility costs of high temperatures, representing an important determinant of population persistence during climate change.

Persistence of giants: population dynamics of the limpet Scutellastra laticostata on rocky shores in Western Australia

2020 ◽  
Vol 646 ◽  
pp. 79-92
Author(s):  
RE Scheibling ◽  
R Black
Keyword(s):  
Population Dynamics ◽  
Western Australia ◽  
Size Structure ◽  
Survival Rates ◽  
Maximum Size ◽  
High Rate ◽  
Adult Survival ◽  
Rocky Shores ◽  
Adult Size ◽  
Decadal Time Scale

Population dynamics and life history traits of the ‘giant’ limpet Scutellastra laticostata on intertidal limestone platforms at Rottnest Island, Western Australia, were recorded by interannual (January/February) monitoring of limpet density and size structure, and relocation of marked individuals, at 3 locations over periods of 13-16 yr between 1993 and 2020. Limpet densities ranged from 4 to 9 ind. m-2 on wave-swept seaward margins of platforms at 2 locations and on a rocky notch at the landward margin of the platform at a third. Juvenile recruits (25-55 mm shell length) were present each year, usually at low densities (<1 m-2), but localized pulses of recruitment occurred in some years. Annual survival rates of marked limpets varied among sites and cohorts, ranging from 0.42 yr-1 at the notch to 0.79 and 0.87 yr-1 on the platforms. A mass mortality of limpets on the platforms occurred in 2003, likely mediated by thermal stress during daytime low tides, coincident with high air temperatures and calm seas. Juveniles grew rapidly to adult size within 2 yr. Asymptotic size (L∞, von Bertalanffy growth model) ranged from 89 to 97 mm, and maximum size from 100 to 113 mm, on platforms. Growth rate and maximum size were lower on the notch. Our empirical observations and simulation models suggest that these populations are relatively stable on a decadal time scale. The frequency and magnitude of recruitment pulses and high rate of adult survival provide considerable inertia, enabling persistence of these populations in the face of sporadic climatic extremes.

High Temperature n- and p-type Doped Microcrystalline Silicon Layers Grown by VHF PECVD Layer-by-Layer Deposition

2003 ◽  
Vol 762 ◽  
Author(s):  
A. Gordijn ◽  
J.K. Rath ◽  
R.E.I. Schropp
Keyword(s):  
Activation Energy ◽  
High Temperature ◽  
High Temperatures ◽  
Continuous Wave ◽  
Hydrogen Plasma ◽  
Silicon Layer ◽  
Dark Conductivity ◽  
High Deposition Rate ◽  
Layer By Layer ◽  
Microcrystalline Silicon

AbstractDue to the high temperatures used for high deposition rate microcrystalline (μc-Si:H) and polycrystalline silicon, there is a need for compact and temperature-stable doped layers. In this study we report on films grown by the layer-by-layer method (LbL) using VHF PECVD. Growth of an amorphous silicon layer is alternated by a hydrogen plasma treatment. In LbL, the surface reactions are separated time-wise from the nucleation in the bulk. We observed that it is possible to incorporate dopant atoms in the layer, without disturbing the nucleation. Even at high substrate temperatures (up to 400°C) doped layers can be made microcrystalline. At these temperatures, in the continuous wave case, crystallinity is hindered, which is generally attributed to the out-diffusion of hydrogen from the surface and the presence of impurities (dopants).We observe that the parameter window for the treatment time for p-layers is smaller compared to n-layers. Moreover we observe that for high temperatures, the nucleation of p-layers is more adversely affected than for n-layers. Thin, doped layers have been structurally, optically and electrically characterized. The best n-layer made at 400°C, with a thickness of only 31 nm, had an activation energy of 0.056 eV and a dark conductivity of 2.7 S/cm, while the best p-layer made at 350°C, with a thickness of 29 nm, had an activation energy of 0.11 V and a dark conductivity of 0.1 S/cm. The suitability of these high temperature n-layers has been demonstrated in an n-i-p microcrystalline silicon solar cell with an unoptimized μc-Si:H i-layer deposited at 250°C and without buffer. The Voc of the cell is 0.48 V and the fill factor is 70 %.

Study and Application of Shallow Water Fracturing Fluid in High Temperature Deep Carbonate Reservoir

2013 ◽  
Author(s):  
Mingguang Che ◽  
Yonghui Wang ◽  
Xingsheng Cheng ◽  
Yongjun Lu ◽  
Yongping Li ◽  
...  
Keyword(s):  
High Temperature ◽  
Shallow Water ◽  
Carbonate Reservoir ◽  
Fracturing Fluid

NICROFER 5520 Co

Alloy Digest ◽  
1995 ◽  
Vol 44 (3) ◽  
Keyword(s):  
High Temperature ◽  
Chemical Composition ◽  
Physical Properties ◽  
Tensile Properties ◽  
High Temperatures ◽  
Heat Treating ◽  
High Temperature Corrosion ◽  
Creep Properties ◽  
Nickel Chromium ◽  
Temperature Performance

Abstract NICROFER 5520 Co is a nickel-chromium-cobalt-molybdenum alloy with excellent strength and creep properties up to high temperatures. Due to its balanced chemical composition the alloy shows outstanding resistance to high temperature corrosion in the form of oxidation and carburization. This datasheet provides information on composition, physical properties, elasticity, and tensile properties. It also includes information on high temperature performance as well as forming, heat treating, machining, and joining. Filing Code: Ni-480. Producer or source: VDM Technologies Corporation.

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