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1.
Experimental studies on the abundance dynamics and thermal tolerance of cladoceran Ceriodaphnia quadrangula (O.F. Müller, 1785) as they depend on the value and action pattern of a thermal factor, as well as field observations and
mathematical calculations were carried out. Based upon the results of these studies, the values of the temperature zone of
normal vital functions (17.0–25.0°C) and of the zones of temperature “static” optimum (21.4–25.0°C) were determined for C. quadrangula. It was shown using experimental populations of C. quadrangula as an example that it is necessary not only to keep the range of the factor optimal values within the tolerance scale (i.e.,
the static optimum) but also to maintain the optimal parameters of dynamic factor changes (or “dynamic optimum”) in order
to form optimal conditions for their growth and development. For C. quadrangula this dynamic temperature optimum is 24.0 ± 1.1°C, with non-periodical (graded) warming to 24.7–25.3°C over five to eight
days. 相似文献
2.
The final preferable temperature (FPT) and avoidance temperature (AT) were determined in parthenogenetic females of the crustacean
Daphnia magna Strauss. The animals were preliminary acclimated to constant temperature of 23.4°C followed by keeping them in a thermo-gradient
device for 24 days. It was revealed that daphnia select FPT with overshoot. In the first four days, daphnia selected temperatures
0.6–1.6°C higher than the acclimation temperature and 4–7.4°C higher than FPT. Two zones of FPT are revealed: the first zone
by the time of 5–13 days (17.6 ± 1.2°C); the second, by 16–24 days (20 ± 1.5°C). The dynamics of AT diapason followed the
dynamics of FPT. Two zones of the AT plateau were observed: over five to 17 days (temperatures <14°C and >25.8°C were avoided)
and for 21–24 days (<8.5°C and >26°C). 相似文献
3.
Dr. Erich Kessler 《Plant Systematics and Evolution》1985,151(1-2):67-71
The upper limit of temperature for growth is a species-specific character in the genusChlorella. The limits of 14Chlorella species range from 26–30°C (C. saccharophila) to 38–42°C (C. sorokiniana), withC. fusca var.vacuolata (34°C) andC. kessleri (34–36°C) assuming an intermediate position. Thus, there is no wide gap in the temperature limits between the normal (“low-temperature”)
species ofChlorella and the “high-temperature” species,C. sorokiniana. 相似文献
4.
Characterization of thermal tolerances of ants, which are both abundant and important in most terrestrial ecosystems, is needed
since thermal constraints can inform how a species may respond to local climatic change. Here we identified the thermal tolerances
of 16 common ant species of the Northeastern United States and determined relationships between body size, desiccation, and
thermal tolerance among species. We hypothesized that maximum heat tolerances of these species would differ and be related
to body size and capacity to resist desiccation. We identified four distinct groups of species belonging to one of three subfamilies,
Dolichoderinae, Formicinae, or Myrmicinae, with different maximum thermal tolerances. Group “a” had a mean thermal tolerance
of approximately 43°C (±1°C), group “b” had a mean thermal tolerance of 40°C (±1°C), group “c” had a mean thermal tolerance
of 38°C (±0°C), and group “d” had a mean thermal tolerance of 36°C (±0°C). Groups “a” and “d” consisted of a single species
(in the subfamilies Myrmicinae and Formicinae, respectively), while groups “b” and “c” were a mix of species in the subfamilies
Myrmicinae, Formicinae, and Dolichoderinae. In the subfamily Formicinae, thermal tolerance increased with body size and critical
water content, a metric of desiccation tolerance. In contrast, in the subfamily Myrmicinae, higher thermal tolerance was correlated
with intermediate body size and lower critical water content. These findings suggest that the two dominant subfamilies in
Northeastern deciduous forests have different relationships between body size, capacity to tolerate desiccation, and thermal
tolerances across species. This variation in thermal tolerance suggests that climatic change may impact species differently. 相似文献
5.
Glenn J. Lurman Christian H. Bock Hans-O. Poertner 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》2009,179(5):623-633
Thermal acclimation is frequently cited as a means by which ectothermic animals improve their Darwinian fitness, i.e. the
beneficial acclimation hypothesis. As the critical swimming speed (U
crit) test is often used as a proxy measure of fitness, we acclimated Atlantic cod (Gadus morhua) to 4 and 10°C and then assessed their U
crit swimming performance at their respective acclimation temperatures and during acute temperature reversal. Because phenotypic
differences exist between different populations of cod, we undertook these experiments in two different populations, North
Sea cod and North East Arctic cod. Acclimation to 4 or 10°C had a minimal effect on swimming performance or U
crit, however test temperature did, with all groups having a 10–17% higher U
crit at 10°C. The swimming efficiency was significantly lower in all groups at 4°C arguably due to the compression of the muscle
fibre recruitment order. This also led to a reduction in the duration of “kick and glide” swimming at 4°C. No significant
differences were seen between the two populations in any of the measured parameters, due possibly to the extended acclimation
period. Our data indicate that acclimation imparts little benefit on U
crit swimming test in Atlantic cod. Further efforts need to identify the functional consequences of the long-term thermal acclimation
process. 相似文献
6.
Significant increases in heat tolerance (time of survival at 14°C) were observed for some, but not all, species of notothenioid fishes collected from McMurdo Sound, Antarctica (77°51′S) following acclimation to 4°C. The increase in thermal tolerance was rapid in Trematomus bernacchii, developing within 1–2 days of acclimation to 4°C. Long-term (6–8 weeks) acclimation to 4°C led to greater heat tolerance in Trematomus pennellii than in T. bernacchii. Unlike its demersal congeners, the cryopelagic notothenioid Pagothenia borchgrevinki did not increase heat tolerance during warm acclimation. A deep-living zoarcid fish, Lycodichthys dearborni, also failed to increase heat tolerance, but survived significantly (> threefold) longer at 14°C than the notothenioids. 相似文献
7.
Jeffrey R. Ziegeweid Cecil A. Jennings Douglas L. Peterson 《Environmental Biology of Fishes》2008,82(3):299-307
Many populations of shortnose sturgeon, Acipenser brevirostrum, in the southeastern United States continue to suffer from poor juvenile recruitment. High summer water temperatures, which
may be exacerbated by anthropogenic activities, are thought to affect recruitment by limiting available summer habitat. However,
information regarding temperature thresholds of shortnose sturgeon is limited. In this study, the thermal maximum method and
a heating rate of 0.1°C min−1 was used to determine critical and lethal thermal maxima for young-of-the-year (YOY) shortnose sturgeon acclimated to temperatures
of 19.5 and 24.1°C. Fish used in the experiment were 0.6 to 35.0 g in weight and 64 to 140 days post hatch (dph) in age. Critical
thermal maxima were 33.7°C (±0.3) and 35.1°C (±0.2) for fish acclimated to 19.5 and 24.1°C, respectively. Critical thermal
maxima significantly increased with an increase in acclimation temperature (p < 0.0001). Lethal thermal maxima were 34.8°C (±0.1) and 36.1°C (±0.1) for fish acclimated to 19.5 and 24.1°C, respectively.
Lethal thermal maxima were significantly affected by acclimation temperature, the log10 (fish weight), and the interaction between log10(fish weight) and acclimation temperature (p < 0.0001). Thermal maxima were used to estimate upper limits of safe temperature, thermal preferences, and optimal growth
temperatures of YOY shortnose sturgeon. Upper limits of safe temperature were similar to previous temperature tolerance information
and indicate that summer temperatures in southeastern rivers may be lethal to YOY shortnose sturgeon if suitable thermal refuge
cannot be found. 相似文献
8.
Jason E. Podrabsky Dustin Clelen Larry I. Crawshaw 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2008,194(4):385-393
Austrofundulus limnaeus thrive in ephemeral ponds that may experience temperatures spanning a range of over 20°C on a daily basis. We hypothesized
that A. limnaeus may have mechanisms, either behavioral or physiological, that allow them to support successful reproduction in this environment.
To evaluate this hypothesis, we exposed male and female adult A. limnaeus to constant 26°C and cycling 21–37°C acclimation regimes in the laboratory and then determined their temperature preference
and reproductive fitness. Temperature preference was determined using a thermal gradient. We demonstrated that A. limnaeus is capable of accurate behavioral thermoregulation, has a final thermal preferendum near 26°C, and exhibits a daily cycle
of temperature preference. Exposure to a cycling temperature regime has an acute effect on thermal preference that differs
between the sexes. Reproductive capability was negatively affected by the cyclic temperature exposure. These findings suggest
that thermal partitioning between males and females may be a natural part of the ecology of A. limnaeus. In addition, it appears that behavioral thermoregulation, or partitioning of reproductive events to the cool parts of the
thermoperiod, are likely to be critical to support successful reproduction in natural populations of A. limnaeus. 相似文献
9.
10.
Yang J Sun YY An H Ji X 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》2008,178(3):343-349
We acclimated adults of Takydromus septentrionalis (northern grass lizard) from four localities (populations) under identical thermal conditions to examine whether local thermal
conditions have a fixed influence on thermal preference and thermal tolerance in the species. Selected body temperature (Tsel),
critical thermal minimum (CTMin), and critical thermal maximum (CTMax) did not differ between sexes and among localities in
lizards kept under identical laboratory conditions for ∼5 months, and the interaction effects between sex and locality on
these measures were not significant. Lizards acclimated to the three constant temperatures (20, 25, and 35°C) differed in
Tsel, CTMin, and CTMax. Tsel, CTMin, and CTMax all shifted upward as acclimation temperature increased, with Tsel shifting
from 32.0 to 34.1°C, CTMin from 4.9 to 8.0°C, and CTMax from 42.0 to 44.5°C at the change-over of acclimation temperature
from 20 to 35°C. Lizards acclimated to the three constant temperatures also differed in the range of viable body temperatures;
the range was widest in the 25°C treatment (38.1°C) and narrowest in the 35°C treatment (36.5°C), with the 20°C treatment
in between (37.2°C). The results of this study show that local thermal conditions do not have a fixed influence on thermal
preference and thermal tolerance in T. septentrionalis. 相似文献
11.
K. R. Jumbam J. S. Terblanche J. A. Deere M. J. Somers S. L. Chown 《Polar Biology》2008,31(2):215-220
Despite the relative richness of spider species across the Southern Ocean islands remarkably little information is available
on their biology. Here, the critical thermal limits of an indigenous (Myro kerguelenensis, Desidae) and an introduced (Prinerigone vagans, Linyphiidae) spider species from Marion Island were studied after 7–8 days acclimation to 0, 5, 10 and 15°C. Critical thermal
minima (CTMin) were low in these species by comparison with other spiders and insects measured to date, and ranged from −6 to −7°C in M. kerguelenensis and from −7 to −8°C in P. vagans. In contrast, critical thermal maxima (CTMax) were similar to other insects on Marion Island (M. kerguelenensis: 35.0–35.6°C; P. vagans: 35.1–36.0°C), although significantly lower than those reported for other spider species in the literature. The magnitude
of acclimation responses in CTMax was lower than those in CTMin for both species and this suggests decoupled responses to acclimation. Whilst not conclusive, the results raise several important
considerations: that oxygen limitation of thermal tolerance needs to be more widely investigated in terrestrial species, that
indigenous and alien species might differ in the nature and extent of their plasticity, and that upper and lower thermal tolerance
limits might be decoupled in spiders as is the case in insects. 相似文献
12.
Pre-dispersal seed predators of quickly maturing inflorescences of Asteraceae are constrained by shortage of development time.
At seed dispersal, they should pupate or, if still immature, relocate into another inflorescence. To investigate how dominant
coleopteran predators of dandelion seed, Glocianus punctiger (Curculionidae) and Olibrus bicolor (Phalacridae), cope with time limitation we combined observation (development and temperature of dandelion capitulum, thermal
constants of predator development, age structure of larval populations at seed dispersal) and analogy (“rate isomorphy” in
predator development, comparing “model” coleopteran species with similar temperature requirements). Development of a dandelion
capitulum takes 21 days. The time available to G. punctiger (140–190 day degrees, development threshold 6.3°C) is sufficient to complete development and pupate after seed dispersal.
By contrast, only 30–50 day degrees are available to O. bicolor (threshold 13.5°C) and this is not enough to complete development and consequently immature larvae should move to other capitula
to continue feeding until pupation. These contrast strategies which are determined by this thermal adaptation, are accompanied
by differences in larval morphology. The “cold adapted” G. punctiger has an apodous larva not capable of migrating between capitula while the “warm adapted” O. bicolor has a mobile campodeiform larva capable of migration. 相似文献
13.
Tingbing Zhu Xuemei Li Xingbing Wu Deguo Yang 《Zeitschrift fur angewandte Ichthyologie》2019,35(6):1281-1285
Schizopygopsis younghusbandi is an endemic fish of Tibet characterized by slow growth. Artificial stock enhancement was applied to rebuild the natural population of S. younghusbandi in recent years. However, the optimal growth temperature and thermal tolerance of S. younghusbandi has not been studied, which restricts the production of S. younghusbandi fingerling for stock enhancement. The purpose of this paper is to determine the growth, critical thermal maximum (CTMax), lethal thermal maximum (LTMax) and acclimation response ratio (ARR) of S. younghusbandi juveniles (body weight 5.7 ± 1.2 g) at three acclimation temperature levels (10, 15, 20°C). The results showed that acclimation temperature significantly affected the growth, CTMax, LTMax and ARR of the experimental fish. Largest final weight (7.5 ± 2.3 g) was recorded in 15°C group. At a heating rate of 1°C/30 min, CTMax ranged from 30.98 to 32.01°C and LTMax ranged from 31.76 to 32.31°C in the three acclimation temperatures. Schizopygopsis younghusbandi had lower ARR value (0.097) than most other fish species. Low ARR value indicates that S. younghusbandi may have narrower thermal tolerance range and weaker acclimation ability to global warming. For successful aquaculture of S. younghusbandi juveniles, temperature should be maintained around 15°C. 相似文献
14.
Variation of total soluble seminal root proteins of tetraploid wild and cultivated wheat induced at cold acclimation and freezing 总被引:2,自引:0,他引:2
The relationship between total soluble seminal root proteins induced at cold acclimation and freezing tolerance in tetraploid
wild wheat Aegilops L. (Ae. biuncialis, Ae. cylindrica) and cultivated wheat Triticum turgitum L. (Firat-93, Harran-95) was investigated. Cold acclimation was performed at 0 °C for 7 days. Freezing tolerance was determined
with survived roots after freezing treatments at −5 and/or −7 °C for 3, 6, 12 and 24 h. At −5°C, all tetraploid genotypes
showed over 60% tolerance for 3 h. This effect was also present in wild wheat for 6 h, but was decreased in cultivated wheat
to 30–35% tolerance for 6 h. Only Ae. biuncialis was able to show 52% tolerance just for 3 h freezing period at −7 °C. However, all the genotypes were not survived at −7
°C, for 6, 12 and 24 h. Cold acclimation induced greater amounts of new soluble seminal root proteins in tolerant Ae. biuncialis (29–104 kDa, pI 5.4–7.4) than in sensitive Harran-95 (29–66 kDa, pI 6.1–8.3). Synthesis and accumulation of these proteins
may be related to degree of freezing tolerance of these genotypes. 相似文献
15.
This study compares the thermal ecology of male bearded dragon lizards (Pogona barbata) from south-east Queensland across two seasons: summer (1994–1995) and autumn (1995). Seasonal patterns of body temperature
(T
b) were explored in terms of changes in the physical properties of the thermal environment and thermoregulatory effort. To
quantify thermoregulatory effort, we compared behavioral and physiological variables recorded for observed lizards with those
estimated for a thermoconforming lizard. The study lizards' field T
bs varied seasonally (summer: grand daily mean (GDM) 34.6 ± 0.6°C, autumn: GDM 27.5 ± 0.3°C) as did maximum and minimum available
operative temperatures (summer: GDM T
max 42.1 ± 1.7°C, T
min 32.2 ± 1.0°C, autumn: GDM T
max 31.7 ± 1.2°C, T
min 26.4 ± 0.5°C). Interestingly, the range of temperatures that lizards selected in a gradient (selected range) did not change
seasonally. However, P. barbata thermoregulated more extensively and more accurately in summer than in autumn; lizards generally displayed behaviors affecting
heat load nonrandomly in summer and randomly in autumn, leading to the GDM of the mean deviations of lizards' field T
bs from their selected ranges being only 2.1 ± 0.5°C in summer, compared to 4.4 ± 0.5°C in autumn. This seasonal difference
was not a consequence of different heat availability in the two seasons, because the seasonally available ranges of operative
temperatures rarely precluded lizards from attaining field T
bs within their selected range, should that have been the goal. Rather, thermal microhabitat distribution and social behavior
appear to have had an important influence on seasonal levels of thermoregulatory effort.
Received: 28 April 1997 / Accepted: 29 December 1997 相似文献
16.
Development, survival, fecundity, progeny sex ratio (PSR) and age-specific life-table parameters of the parasitoid Campoletis chlorideae Uchida (Hymenoptera: Ichneumonidae) were examined at six different constant temperatures (12, 17, 22, 27, 32 and 37°C) in
the laboratory [70 ± 10% RH and 10:14 h (light:dark) photoperiod]. Second instar larvae of Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) were reared on chickpea (Cicer arietinum L.) and used as the host. Development times shortened as the temperature increased from 12 to 37°C. The estimated lower developmental
threshold (tL) was 3.4°C. The thermal summation for total immature stages was 379.97 degree-days. A reciprocal relationship between temperature
and longevity was observed in the range of 12–17°C. The maximum mortality of pupae (71.8%) occurred at 37°C. At 22°C, the
yield of a female parasitoid averaged 137.3 ± 14.7 (mean ± SD) progeny, of which 89.6 ± 7.6 were daughters. The number of
daughters produced decreased when the females were kept either above or below 22°C, although the PSR was female biased in
the range of 17–27°C. The analyses of life-table parameters, developmental rates, reproduction, mortality and PSR suggest
that maximum population growth (r
m
) is near 27°C. There was little variation observed in most of the desired qualities of C. chlorideae in the range of 17–27°C, and it appears that the parasitoid is adapted to a wide range of temperatures. We suggest that for
maximum production the parasitoid should be reared at 22 ± 4°C and be released in areas where the temperature ranges between
17° and 27°C, as in the plains of northern India. 相似文献
17.
In reef corals, much research has focused on the capacity of corals to acclimatize and/or adapt to different thermal environments,
but the majority of work has focused on distinctions in mean temperature. Across small spatial scales, distinctions in daily
temperature variation are common, but the role of such environmental variation in setting coral thermal tolerances has received
little attention. Here, we take advantage of back-reef pools in American Samoa that differ in thermal variation to investigate
the effects of thermally fluctuating environments on coral thermal tolerance. We experimentally heat-stressed Acropora hyacinthus from a thermally moderate lagoon pool (temp range 26.5–33.3°C) and from a more thermally variable pool that naturally experiences
2–3 h high temperature events during summer low tides (temp range 25.0–35°C). We compared mortality and photosystem II photochemical
efficiency of colony fragments exposed to ambient temperatures (median: 28.0°C) or elevated temperatures (median: 31.5°C).
In the heated treatment, moderate pool corals showed nearly 50% mortality whether they hosted heat-sensitive (49.2 ± 6.5%
SE; C2) or heat-resistant (47.0 ± 11.2% SE; D) symbionts. However, variable pool corals, all of which hosted heat-resistant
symbionts, survived well, showing low mortalities (16.6 ± 8.8% SE) statistically indistinguishable from controls held at ambient
temperatures (5.1–8.3 ± 3.3–8.3% SE). Similarly, moderate pool corals hosting heat-sensitive algae showed rapid rates of decline
in algal photosystem II photochemical efficiency in the elevated temperature treatment (slope = −0.04 day−1 ± 0.007 SE); moderate pool corals hosting heat-resistant algae showed intermediate levels of decline (slope = −0.039 day−1 ± 0.007 SE); and variable pool corals hosting heat-resistant algae showed the least decline (slope = −0.028 day−1 ± 0.004 SE). High gene flow among pools suggests that these differences probably reflect coral acclimatization not local
genetic adaptation. Our results suggest that previous exposure to an environmentally variable microhabitat adds substantially
to coral–algal thermal tolerance, beyond that provided by heat-resistant symbionts alone. 相似文献
18.
The faunistic composition of pelagic ostracods of regions situated to the north and northwest of the d’Urville Sea (60°–65°S,
148°–136° and 136°–113°E) is largely similar to that of the area adjacent to the Somov Sea at the same latitudes. Alacia hettacra is the most abundant species here; Austrinoecia isocheira, Boroecia antipoda, and Obtusoecia antarctica are common species. The maximum abundance of pelagic ostracods is observed in the 100–200 m depth range; the largest contribution
to it is contributed by A. hettacra. The number of species increases with increasing depth. The 64°–65°S region between 148° and 113° E is regarded as the northern
boundary of the “Polar Antarctic zone.” 相似文献
19.
Verena Fettinger Frans J. M. Smulders Peter Lazar Irem Omurtag Peter Paulsen 《European Journal of Wildlife Research》2010,56(6):943-947
In two surveys, thighs of a total of 137 hunted hares were tested for the presence of intramuscular shots and femur fractures,
which were detected in 42.7% and 29.2% of 274 thighs, respectively. Femur fractures were significantly associated with the
presence of intramuscular shots. In the second survey (46 hares), 92 thighs were grouped into three categories, “A” (no fractures,
no intramuscular shot), “B” (one intramuscular shot), and “C” (multiple shots and hematoma), with 49.0%, 33.6%, and 17.4%,
respectively. Category “C” was found unfit for human consumption. During 7-day storage of vacuum-packed “A” and “B” thighs,
total aerobic counts increased from initially 3.3 ± 0.3 (mean ± SD) and 4.1 ± 0.6 log cfu/g by ca. 2 log units when stored
at 3–4°C, whereas the increase was clearly <1 log unit at 0°C. In comparison to temperature, differences between “A” and “B”
category were less pronounced. Similar dynamics were observed for Enterobacteriaceae. In all categories, muscle pH values
(mean = 5.83) were similar. It is concluded that storage at temperatures of ca. 4°C, although in compliance with EU legislation,
does not afford keeping microbial contaminants in check, and thus will not preserve microbiological quality of vacuum-packed
hare meat. 相似文献
20.
Ontogenetic changes and temperature dependency of respiration rate were studied in Dendrobaena mrazeki, an earthworm species inhabiting relatively warm and dry habitats in Central Europe. D. mrazeki showed respiration rate lower than in other earthworm species, < 70 μl O2 g−1 h−1, within the temperature range of 5–35°C. The difference of respiration rate between juveniles and adults was insignificant
at 20°C. The response of oxygen consumption to sudden temperature changes was compared with the temperature dependence of
respiratory activity in animals pre-acclimated to temperature of measurement. No significant impact of acclimation on the
temperature response of oxygen consumption was found. The body mass-adjusted respiration rate increased slowly with increasing
temperature from 5 to 25°C (Q10 from 1.2 to 1.7) independently on acclimation history of earthworms. Oxygen consumption decreased above 25°C up to upper
lethal limit (about 35°C). Temperature dependence of metabolic rate is smaller than in other earthworm species. The relationships
between low metabolic sensitivity to temperature, slow locomotion and reactivity to touching as observed in this species are
discussed. 相似文献