scholarly journals The Impacts ofEx SituTransplantation on the Physiology of the Taiwanese Reef-Building CoralSeriatopora hystrix

2013 ◽  
Vol 2013 ◽  
pp. 1-11 ◽  
Author(s):  
Anderson B. Mayfield ◽  
Tung-Yung Fan ◽  
Chii-Shiarng Chen

We sought to determine whether the Indo-Pacific reef-building coralSeriatopora hystrixperforms in a similar manner in the laboratory as it doesin situby measuringSymbiodiniumdensity, chlorophyll a (chl-a) concentration, and the maximum quantum yield of photosystem II (FV/FM) at the time of field sampling (in situ), as well as after three weeks of acclimation and one week of experimentation (ex situ).Symbiodiniumdensity was similar between corals of the two study sites, Houbihu (an upwelling reef) and Houwan (a nonupwelling reef), and also remained at similar levelsex situasin situ. On the other hand, both areal and cell-specific chl-aconcentrations approximately doubledex siturelative toin situ, an increase that may be due to having employed a light regime that differed from that experienced by these corals on the reefs of southern Taiwan from which they were collected. As this change inSymbiodiniumchl-acontent was documented in corals of both sites, the experiment itself was not biased by this difference. Furthermore,FV/FMincreased by only 1%ex siturelative toin situ, indicating that the corals maintained a similar level of photosynthetic performance as displayedin situeven after one month in captivity.

Koedoe ◽  
1993 ◽  
Vol 36 (1) ◽  
Author(s):  
Dirk Wessels ◽  
Ludger Kappen

The photosynthetic behaviour of endolithic andepilithic lichens characteristic of sedimentary and volcanic rock was investigated in situ in the Mountain Zebra National Park, South Africa. The park forms part of an inland semi-desert known as the Karoo, in the Cape Province. Temperatures within Balfour sandstone were monitored, the results showing that during the early morning, temperatures within the sandstone were nearly 5@C lower than ambient air temperatures. This may enhance the frequency of water condensing on the sandstone, which may be particularly important for the endoliths Leciclea aff. sarcogynoides and Sarcogyne cf. austroafricana. Maximum photosynthetic rates of the investigated species were found at temperatures between 20@C and 30@C, far higher than the recorded optimum temperatures for lichens from temperate and desert regions. Parmelia chlorea was the most productive species. Compared to the other epiliths, Peltula capensis was found to be a moderately productive species. The photosynthetic gain of Leciclea aff. sarcogynoides and Sarcogyne cf. austro-africana was low, but the photosynthetic gain of these two species still exceeded that of Acarospora sp.


2019 ◽  
Vol 15 (S352) ◽  
pp. 287-290
Author(s):  
Ken-ichi Tadaki ◽  
Daisuke Iono

AbstractSubmillimeter galaxies at z > 3 building up their central cores through compact starbursts with an effective radius of 1–2 kpc. Our ALMA high-resolution observations reveal off-center gas clumps in a submillimeter galaxy at z = 4.3, COSMOS-AzTEC-1, as well as a rotation-dominated disk. Exploiting the kinematic properties and the spatial distribution of gas mass surface density, we find that the starburst disk is gravitationally unstable. This result is consistent with a scenario where in-situ clumps are formed through disk instability. On the other hand, we find evidence for an ex-situ clump that does not corotate with the starburst disk. The accretion of such a non-corotating clump could stimulate violent disk instability, driving gas inflows into the central regions of the galaxy. Our results suggest that compact cores are formed through an extreme starburst due to a gravitational instability, triggered by non-corotating clumps.


2021 ◽  
Vol 4 (2) ◽  
pp. 42
Author(s):  
I Putu Dede Charles Dharma Saputra ◽  
IGB Sila Dharma ◽  
Yulianto Suteja ◽  
Widiastuti Widiastuti

Bali island has many magnificent underwater coral reef gardens that attract tourists. Besides Pemuteran and Menjangan island waters,  Batu Sungu water has also potential to be a new tourist destination. Thus, to determine the potency and management plan in Batu Sungu waters, this research aimed to examine the overall coral cover, coral growth forms, other benthic forms, and each of their components in 5 and 10 m depths.  The overall coral cover, coral growth forms, other benthic forms, and each of their components were counted by using the Line Intercept Transect (LIT) method. Before collecting data, study sites were observed by using the Manta Tow method. Data were collected in 2 depths (5 dan 10 m) with 5 sites each (replicates) that separates within 50 to 150 m. A 25 m LIT was spread parallel to the coastline above the reefs. Live coral colonies, other benthic forms below the transects were measured for the number, length, and growth forms. Water quality was measured in situ (temperature, current, and clarity) and ex situ (pH). Results showed that the category of coral coverage in Batu Sungu water is "good” in 5 m and "moderate” in 10 m whereas there was no significant difference among each component of the overall coral cover. The most dominant coral growth form among the 2 depths was Coral Massive whereas significantly abundant in 5 m. Moreover, the number of Coral Foliose was found significantly high in the same depth. Other coral growth forms were relatively similar in numbers in two depths.  As likewise, the cover of other benthic forms and its component were not significantly different among two depths, except  Dead Coral with Algae which significantly plentiful in 5 m. Sand was dominantly found in two depths with no significant difference. Furthermore, Coraline Alga was only observed in 5 m, however, there were no Macroalga and Alga Assemblages found at this depth. It is assumed that the similarity number of the overall coral cover, coral growth forms, other benthic forms, and each of their components is related to the alikeness of water quality among the two depths. 


PeerJ ◽  
2015 ◽  
Vol 3 ◽  
pp. e1406 ◽  
Author(s):  
Melissa R. Price ◽  
David Sischo ◽  
Mark-Anthony Pascua ◽  
Michael G. Hadfield

Wild populations of endangered Hawaiian tree snails have declined precipitously over the last century due to introduced predators and other human impacts. Life history traits, such as very low fecundity (<5 offspring per year across taxa) and maturity at approximately four years of age have made recovery difficult. Conservation efforts such asin situpredator-free enclosures may increase survival to maturity by protecting offspring from predation, but no long-term data existed prior to this study demonstrating the demographic and genetic parameters necessary to maintain populations within those enclosures. We evaluated over 20 years of evidence for the dynamics of survival and extinction in captiveex situpopulations of Hawaiian tree snails established from wild-collected individuals. From 1991 to 2006, small numbers of snails (<15) from fifteen species were collected from the wild to initiate captive-reared populations as a hedge against extinction. This small number of founders resulted in a severe bottleneck in each of the captive-reared populations. We identified key demographic parameters that predicted population recovery from this bottleneck. Species with captive populations that produced between two and four offspring per adult per year and had 20–50% of those offspring survive to maturity recovered to numbers above 100 individuals, and maintained viable populations following a decline that occurred between 2009 and 2014. Those populations that had less than two offspring per adult per year and less than 20% survival to maturity did not reach 100 individuals in captivity, and many of these populations died out during the recent decline. We suggest that small reductions in fitness may contribute to extirpation in taxa with inherently low fecundity, by keeping populations below a threshold number essential to long-term recovery. Futureex situpopulations should be founded with no less than 15 adults, and maintained in conditions closely approximating the temperature and humidity of source locations to optimize fitness. Permanent translocations of wild populations for conservation purposes will be more likely to succeed with greater than 100 adults, and should be limited to locations with a similar climate to source locations.


2006 ◽  
Vol 75 (03-04) ◽  
pp. 161-168 ◽  
Author(s):  
Vincent Nijman

The Javan gibbon Hylobates moloch is confined to the last remnants of rainforest on the island of Java, Indonesia. As of 2002, the species has been recorded in 29 forest areas, and the wild population is conservatively estimated at 4100-4500 individuals. Over 95% of the gibbons are in populations of >100 individuals, and the four largest areas support populations of >500 individuals each. In 2003, 56 Javan gibbons were maintained at eight Indonesian zoos, 15 at four Indonesian wildlife rescue centres, with five potential breeding pairs. There is no evidence that the species has bred successfully in captivity in Indonesia. Outside the range country, 48 Javan gibbons were maintained at ten institutions in nine countries, with six breeding pairs. The total ex-situ population is some 120 individuals, the majority of which is wild-caught. At present most initiatives relating to the conservation of the Javan gibbon have targeted small isolated forest areas and the ex-situ population, whereas in-situ protection of the largest populations in the wild has been largely ignored. Significant populations are currently found in unprotected forests. The large captive population of Javan gibbons within Indonesia allows, with improved co-operation, to set up an integrated captive- breeding programme. This should, not be seen, however, as a means to improve the conservation status of the wild Javan gibbons, which needs to be achieved through protection of remaining habitat, but could be used for improving the prevailing low levels of conservation awareness in Java.


2014 ◽  
Vol 5 ◽  
pp. 2129-2138 ◽  
Author(s):  
Laura C Preiss ◽  
Katharina Landfester ◽  
Rafael Muñoz-Espí

Biopolymers and biopolymer colloids can act as controlling agents and templates not only in many processes in nature, but also in a wide range of synthetic approaches. Inorganic materials can be either synthesized ex situ and later incorporated into a biopolymer structuring matrix or grown in situ in the presence of biopolymers. In this review, we focus mainly on the latter case and distinguish between the following possibilities: (i) biopolymers as controlling agents of nucleation and growth of inorganic materials; (ii) biopolymers as supports, either as molecular supports or as carrier particles acting as cores of core–shell structures; and (iii) so-called “soft templates”, which include on one hand stabilized droplets, micelles, and vesicles, and on the other hand continuous scaffolds generated by gelling biopolymers.


Crustaceana ◽  
2021 ◽  
Vol 94 (4) ◽  
pp. 431-446
Author(s):  
Kwee Siong Tew ◽  
Hsin-Ling Chen ◽  
Chiao-Chuan Han

Abstract Previous studies have revealed that reproductive traits of the Oriental river prawn Macrobrachium nipponense (De Haan, 1849) (Palaemonidae) can differ markedly across populations, though the environmental factors responsible for such variation are unknown. We therefore conducted monthly surveys of these prawns to determine their reproductive traits over two years at four study sites in southern Taiwan. The temperature, dissolved oxygen concentration, conductivity, and turbidity in Long Luan Lake significantly differed from the other sites, yet levels of reproductive trait parameters were intermediate among all. The aforementioned environmental factors were similar between the two Sihchong River sites and Mudan Reservoir, yet the river populations had the highest values in all reproductive traits. The river’s substratum was comprised of >60% of cobbles and boulders, whereas <5% of the substratum of the reservoir and lake consisted of such rocks. We therefore suggest that this difference in substrate composition may be linked to the significant differences in reproductive traits observed.


Author(s):  
D. Loretto ◽  
J. M. Gibson ◽  
S. M. Yalisove ◽  
R. T. Tung

The cobalt disilicide/silicon system has potential applications as a metal-base and as a permeable-base transistor. Although thin, low defect density, films of CoSi2 on Si(111) have been successfully grown, there are reasons to believe that Si(100)/CoSi2 may be better suited to the transmission of electrons at the silicon/silicide interface than Si(111)/CoSi2. A TEM study of the formation of CoSi2 on Si(100) is therefore being conducted. We have previously reported TEM observations on Si(111)/CoSi2 grown both in situ, in an ultra high vacuum (UHV) TEM and ex situ, in a conventional Molecular Beam Epitaxy system.The procedures used for the MBE growth have been described elsewhere. In situ experiments were performed in a JEOL 200CX electron microscope, extensively modified to give a vacuum of better than 10-9 T in the specimen region and the capacity to do in situ sample heating and deposition. Cobalt was deposited onto clean Si(100) samples by thermal evaporation from cobalt-coated Ta filaments.


Author(s):  
J. I. Bennetch

In a recent study of the superplastic forming (SPF) behavior of certain Al-Li-X alloys, the relative misorientation between adjacent (sub)grains proved to be an important parameter. It is well established that the most accurate way to determine misorientation across boundaries is by Kikuchi line analysis. However, the SPF study required the characterization of a large number of (sub)grains in each sample to be statistically meaningful, a very time-consuming task even for comparatively rapid Kikuchi analytical techniques.In order to circumvent this problem, an alternate, even more rapid in-situ Kikuchi technique was devised, eliminating the need for the developing of negatives and any subsequent measurements on photographic plates. All that is required is a double tilt low backlash goniometer capable of tilting ± 45° in one axis and ± 30° in the other axis. The procedure is as follows. While viewing the microscope screen, one merely tilts the specimen until a standard recognizable reference Kikuchi pattern is centered, making sure, at the same time, that the focused electron beam remains on the (sub)grain in question.


Author(s):  
K. Barmak

Generally, processing of thin films involves several annealing steps in addition to the deposition step. During the annealing steps, diffusion, transformations and reactions take place. In this paper, examples of the use of TEM and AEM for ex situ and in situ studies of reactions and phase transformations in thin films will be presented.The ex situ studies were carried out on Nb/Al multilayer thin films annealed to different stages of reaction. Figure 1 shows a multilayer with dNb = 383 and dAl = 117 nm annealed at 750°C for 4 hours. As can be seen in the micrograph, there are four phases, Nb/Nb3-xAl/Nb2-xAl/NbAl3, present in the film at this stage of the reaction. The composition of each of the four regions marked 1-4 was obtained by EDX analysis. The absolute concentration in each region could not be determined due to the lack of thickness and geometry parameters that were required to make the necessary absorption and fluorescence corrections.


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