DIEL PERIODICITIES OF EMERGENCE OF SOME HIGH ARCTIC CHIRONOMIDAE (DIPTERA)

1972 ◽  
Vol 104 (6) ◽  
pp. 903-916 ◽  
Author(s):  
H. V. Danks ◽  
D. R. Oliver
Keyword(s):  
Light Intensity ◽  
Water Temperature ◽  
Temperature Fluctuation ◽  
High Arctic ◽  
Middle Part ◽  
Physical Factors ◽  
Short Term ◽  
Temperature Changes ◽  
Emergence Pattern ◽  
Critical Thresholds

AbstractThe diel periodicities of emergence of seven species of chironomids from two ponds in the Hazen Camp area (81°49′ N., 71°18′ W.) are considered in relation to physical factors. Emergence of all species is greatest during the middle part of the day: an increase in water temperature induces emergence and a decrease inhibits it, whereas changes in light intensity, ultraviolet radiation, sunshine, and wind appear to have no effect on the diel emergence pattern. In a shallow pond, males emerge slightly earlier in the day than females in some species. In the same pond also, emergence, particularly of females, is sometimes distinctly bimodal. In a deeper tarn where the diel temperature fluctuation is very small there is a single peak, which is less pronounced than in the shallow pond.That temperature controls the periodicity of emergence implies that short-term temperature changes which may inhibit adult activity are of great importance in the high arctic. At these latitudes, changes in light intensity evidently do not reliably indicate to the emerging organisms temperatures which fluctuate near critical thresholds for activity.

scholarly journals Comparison of Invasive Apple Snail (Pomacea canaliculata) Behaviors in Different Water Temperature Gradients

Water ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 1149
Author(s):  
Mi-Jung Bae ◽  
Eui-Jin Kim ◽  
Young-Seuk Park
Keyword(s):  
Water Temperature ◽  
Farming Systems ◽  
Freshwater Snail ◽  
Freshwater Ecosystems ◽  
Pomacea Canaliculata ◽  
Activity Levels ◽  
Self Organizing Map ◽  
Apple Snail ◽  
Temperature Changes ◽  
Organic Farming Systems

Pomacea canaliculata (known as invasive apple snail) is a freshwater snail native to South America that was introduced into many countries (including Asia and North America) as a food source or for organic farming systems. However, it has invaded freshwater ecosystems and become a serious agricultural pest in paddy fields. Water temperature is an important factor determining behavior and successful establishment in new areas. We examined the behavioral responses of P. canaliculata with water temperature changes from 25 °C to 30 °C, 20 °C, and 15 °C by quantifying changes in nine behaviors. At the acclimated temperature (25 °C), the mobility of P. canaliculata was low during the day, but high at night. Clinging behavior increased as the water temperature decreased from 25 °C to 20 °C or 15 °C. Conversely, ventilation and food consumption increased when the water temperature increased from 25 °C to 30 °C. A self-organizing map (an unsupervised artificial neural network) was used to classify the behavioral patterns into seven clusters at different water temperatures. These results suggest that the activity levels or certain behaviors of P. canaliculata vary with the water temperature conditions. Understanding the thermal biology of P. canaliculata may be crucial for managing this invasive snail.

Feeding rate and efficiency in an apex soil predator exposed to short-term temperature changes

2021 ◽  
Vol 50 ◽  
pp. 87-96
Author(s):  
Divya Ramachandran ◽  
Zoë Lindo ◽  
Matthew L. Meehan
Keyword(s):  
Feeding Rate ◽  
Short Term ◽  
Temperature Changes

scholarly journals Short term fluctuating temperature alleviates Daphnia stoichiometric constraints

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Esteban Balseiro ◽  
Cecilia Laspoumaderes ◽  
Facundo Smufer ◽  
Laura Wolinski ◽  
Beatriz Modenutti
Keyword(s):  
Nutrient Limitation ◽  
Temperature Fluctuation ◽  
Diel Vertical Migration ◽  
Temperature Treatment ◽  
Short Term ◽  
Fluctuating Temperature ◽  
Rna Content ◽  
Temperature Regimes ◽  
Lake Temperature ◽  
The Mean

AbstractIn this study, we analysed how short term temperature fluctuation interacts with nutrient limitation in the vertical migrating Daphnia commutata. We hypothesize that short term (daily) temperature fluctuation will alleviate nutrient limitation. We carried out experiments analysing growth rates, phosphorus and RNA content of D. commutate grown under four different temperature regimes and two P-limited conditions. Our experiments showed that individuals grown under fluctuating temperature grew more than at the mean temperature. We estimated the expected sizes for the 15 °C treatment based on the Q10 and for the fluctuating temperature treatment. These expected sizes for both treatments resulted well below the observed ones. The P and RNA content of individuals grown at 10 °C were significantly higher than those at 20 °C, and when individuals grown at 10 °C were translocated to 20 °C they exerted an increased growth rate. Our results suggest that, under a regime of diel vertical migration, the temperature alternation would allow migrating organisms to alleviate the effect of severe nutrient limitation maintaining population growth. Under a scenario of global warming, where epilimnetic temperatures will increase, lake temperature will interact with nutrient limitation for consumers, but, organisms may be able to face these changes if they can still regularly move from a cold hypolimnion to a warmer epilimnion.

Short-term flow and water temperature fluctuations in Sagami Bay, Japan, associated with variations of the Kuroshio during the non-large-meander path

2012 ◽  
Vol 105 ◽  
pp. 47-60 ◽  
Author(s):  
Daisuke Takahashi ◽  
Akihiko Morimoto ◽  
Tetsuya Nakamura ◽  
Takuji Hosaka ◽  
Yoshihisa Mino ◽  
...  
Keyword(s):  
Water Temperature ◽  
Temperature Fluctuations ◽  
Large Meander ◽  
Short Term ◽  
Sagami Bay ◽  
The Kuroshio

scholarly journals Upper thermal threshold of Lepidurus arcticus (Branchiopoda, Notostraca) in lakes on the southern outreach of its distribution range

2021 ◽  
Vol 41 ◽  
pp. 50-88
Author(s):  
Tore Qvenild ◽  
Eirik Fjeld ◽  
Arne Fjellheim ◽  
Johan Hammar ◽  
Trygve Hesthagen ◽  
...  
Keyword(s):  
Water Temperature ◽  
Fish Predation ◽  
High Arctic ◽  
Water Bodies ◽  
The Arctic ◽  
Thermal Threshold ◽  
Tadpole Shrimp ◽  
Area North ◽  
Regulated Lakes ◽  
Southern Island

The Arctic tadpole shrimp Lepidurus arcticus has a circumpolar distribution and the Scandes (Fennoscandian Mountains) marks its southernmost limit in Europe. Within this area, 391 natural and 88 regulated lakes with L. arcticus have been identified, of which 87% are above the treeline. The lakes hosting L. arcticus decrease in altitude from south to north, which results from its temperature preferences. The majority of the locations are at a lower lake air temperature than 11°C which is equivalent to a water temperature near 14°C. This is assumed to be near the upper thermal threshold for L. arcticus. In lakes that exceed this average summer water temperature (1 July – 15 September), sustainable populations seem to be rare. In warmer lakes, life cycle mismatches are assumed to explain the absence of L. arcticus, most likely by affecting the embryo and juvenile stages. The distribution appears to be dichotomous, with one large northern area north of 65°N and one separated southern “island”. Only two locations of L. arcticus are known for the area between latitudes 62.88 and 64.39°N. In this part of the Scandes, the lakes are likely too warm to host L. arcticus as most of them are situated below 700 m a.s.l. This may also be the case in the northernmost region, north of 70°N, where only 11 populations are recorded. Most of the lakes in this area typically occurs below 400 m a.s.l. L. arcticus populations are sensitive to fish predation, and dense fish populations may be another stressor limiting its distribution. In contrast to water bodies in the High Arctic where L. arcticus only exists in shallow, fishless ponds, in the Scandes they co-exist with fish in 97% of the findings. Global warming has already modified the environment of the Scandes, and populations of L. arcticus are at threat in many of the small and shallow water bodies at low altitudes.

scholarly journals Slow Community Development Enhances Abiotic Limitation of Benthic Community Structure in a High Arctic Kelp Bed

2021 ◽  
Vol 8 ◽  
Author(s):  
Christina Bonsell ◽  
Kenneth H. Dunton
Keyword(s):  
Community Structure ◽  
Community Development ◽  
Benthic Community ◽  
Beaufort Sea ◽  
High Arctic ◽  
Coralline Algae ◽  
Physical Factors ◽  
Crustose Coralline Algae ◽  
Benthic Community Structure ◽  
Kelp Bed

We examined the patterns of propagule recruitment to assess the timescale and trajectory of succession and the possible roles of physical factors in controlling benthic community structure in a shallow High Arctic kelp bed in the Beaufort Sea, Alaska. Spatial differences in established epilithic assemblages were evaluated against static habitat attributes (depth, distance from river inputs) and environmental factors (temperature, salinity, current speed, underwater light) collected continuously over 2–6 years. Our measurements revealed that bottom waters remained below freezing (mean winter temperatures ∼−1.8°C) and saline (33–36) with negligible light levels for 8–9 months. In contrast, the summer open water period was characterized by variable salinities (22–36), higher temperatures (up to 8–9°C) and measurable irradiance (1–8 mol photons m–2 day–1). An inshore, near-river site experienced strong, acute, springtime drops in salinity to nearly 0 in some years. The epilithic community was dominated by foliose red algae (47–79%), prostrate kelps (2–19%), and crustose coralline algae (0–19%). Strong spatial distinctions among sites included a positive correlation between cover by crustose coralline algae and distance to river inputs, but we found no significant relationships between multi-year means of physical factors and functional groups. Low rates of colonization and the very slow growth rates of recruits are the main factors that contribute to prolonged community development, which augments the influence of low-frequency physical events over local community structure. Mortality during early succession largely determines crustose coralline algal and invertebrate prevalence in the established community, while kelp seem to be recruitment-limited. On scales > 1 m, community structure varies with bathymetry and exposure to freshwater intrusion, which regulate frequency of primary and physiological disturbance. Colonization rates (means of 3.3–69.9 ind. 100 cm–1 year–1 site–1) were much lower than studies in other Arctic kelp habitats, and likely reflect the nature of a truly High Arctic environment. Our results suggest that community development in the nearshore Beaufort Sea occurs over decades, and is affected by combinations of recruitment limitation, primary disturbance, and abiotic stressors. While seasonality exerts strong influence on Arctic systems, static habitat characteristics largely determine benthic ecosystem structure by integrating seasonal and interannual variability over timescales longer than most ecological studies.

scholarly journals Fleshy Red Algae Mats Influence Their Environment in the Mediterranean Sea

2021 ◽  
Vol 8 ◽  
Author(s):  
Neele Schmidt ◽  
Yusuf C. El-Khaled ◽  
Felix I. Roßbach ◽  
Christian Wild
Keyword(s):  
Environmental Factors ◽  
Light Intensity ◽  
Water Temperature ◽  
Mediterranean Sea ◽  
Water Column ◽  
Red Algae ◽  
Water Movement ◽  
Ecosystem Engineer ◽  
Overlying Water ◽  
The Mediterranean

In the Mediterranean Sea, the fleshy red alga Phyllophora crispa forms dense mats of up to 15 cm thickness, mainly located on rocky substrates in water depths below 20 m. Because of the observed density of these mats and some first observations, we hypothesize that P. crispa is a yet undescribed ecosystem engineer that provides a multitude of ecological niches for associated organisms along small-scale environmental gradients. Therefore, we conducted an in-situ pilot study in the Western Mediterranean Sea to assess potential influence of the algae mats on the key environmental factors water movement, temperature and light intensity. We comparatively and simultaneously measured in P. crispa mats, in neighboring Posidonia oceanica seagrass meadows, on neighboring bare rocky substrates without algae mats, and in the directly overlying water column. We used several underwater logging sensors and gypsum clod cards. Findings revealed that P. crispa significantly reduced water movement by 41% compared to the overlying water column, whereas water movement was not affected by P. oceanica meadows and bare rocky substrates. Surprisingly, P. crispa increased the water temperature by 0.3°C relative to the water column, while the water temperature in P. oceanica and on bare rocky substrates was reduced by 0.5°C. Light intensity inside the red algae mats was reduced significantly by 69% compared to the water column. This was similar to measured light reduction of 77% by P. oceanica. These findings highlight the strong influence of the dense red algae mats on some key environmental factors. Their influence is obviously similar or even higher than for the well-known seagrass ecosystem engineer. This may be a factor that facilitates associated biodiversity similarly as described for P. oceanica.

Metabolic opportunists: feeding and temperature influence the rate and pattern of respiration in the high arctic woollybear caterpillar gynaephora groenlandica (Lymantriidae)

1999 ◽  
Vol 202 (1) ◽  
pp. 47-53 ◽  
Author(s):  
V.A. Bennett ◽  
O. Kukal ◽  
R.E. Lee
Keyword(s):  
Cold Adaptation ◽  
Freeze Tolerance ◽  
High Arctic ◽  
Temperature Influence ◽  
Temperature Changes ◽  
Respiration Rates ◽  
Polar Environment ◽  
Lepidopteran Larvae ◽  
Gynaephora Groenlandica ◽  
Metabolic Cold Adaptation

Arctic woollybear caterpillars, Gynaephora groenlandica, had the capacity to rapidly and dramatically increase respiration rates up to fourfold within 12–24 h of feeding and exhibited similar decreases in respiration of 60–85 % in as little as 12 h of starvation. At the peak of their feeding season, the respiration rates of caterpillars also increased significantly with temperature from 0.5 to 22 degreesC for both fed and starved caterpillars (Q10=1-5). Indicative of diapause, late season caterpillars had depressed respiration rates which were less sensitive to temperature changes (Q10 approximately 1.5), while respiration rates for caterpillars that had spun hibernacula were even lower. G. groenlandica did not appear to demonstrate metabolic cold adaptation compared with other temperate lepidopteran larvae. The seasonal capacity to adjust metabolic rate rapidly in response to food consumption and temperature (which can be elevated by basking) may promote the efficient acquisition of energy during the brief (1 month) summer growing and feeding season, while conserving energy by entering diapause when conditions are less favorable. These adaptations, along with their long 15–20 year life cycle and the retention of freeze tolerance year-round, promote the survival of G. groenlandica in this harsh polar environment.

The water temperature changes the effect of pH on copper toxicity to the green microalgae Raphidocelis subcapitata

Chemosphere ◽  
2021 ◽  
pp. 133110
Author(s):  
Gissela Pascual ◽  
Daisuke Sano ◽  
Takashi Sakamaki ◽  
Michihiro Akiba ◽  
Osamu Nishimura
Keyword(s):  
Water Temperature ◽  
Copper Toxicity ◽  
Green Microalgae ◽  
Effect Of Ph ◽  
Temperature Changes ◽  
Raphidocelis Subcapitata
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