Habitat use and growth of juvenile ornate rock lobsters, Panulirus ornatus (Fabricius, 1798), in Torres Strait, Australia

1997 ◽  
Vol 48 (8) ◽  
pp. 663 ◽  
Author(s):  
D. M. Dennis ◽  
T. D. Skewes ◽  
C. R. Pitcher
Keyword(s):  
Habitat Use ◽  
Average Density ◽  
Effect Of Temperature ◽  
Depth Range ◽  
Size Distributions ◽  
Field Surveys ◽  
Laboratory Trial ◽  
Torres Strait ◽  
One Year ◽  
North Western

Habitat use and growth of juvenile (8–90 mm carapace length, or CL) ornate rock lobsters, Panulirus ornatus, were described with the aid of information from field surveys in Torres Strait and from a laboratory growth experiment. In north-western Torres Strait, small juveniles (<40 mm CL) sheltered in solution holes in the seabed that matched their body size. Most shelters were in limestone pavement and near macroalgae. Larger juveniles sheltered in both solution holes and crevices. Juveniles were found at all depths sampled (3–21 m), and densities of juveniles were uniform over this depth range. The average density of juveniles in the study area in 1992–93 was 63 ha-1. Size distributions of juveniles sampled during August 1992 to March 1993 showed that early growth was 1·4 mm CL week-1. A laboratory trial to examine the effect of temperature on growth showed that juveniles grew 31% faster at 30°C (0·88 mm CL week-1) compared with growth at 26°C (0·67 mm CL week-1) as a result of shorter moult intervals in large juveniles. Size distributions of juveniles sampled at mid year between 1990 and 1995 showed that 10–20% reach legal size (75 mm CL) about one year after settlement.

scholarly journals Urban aerosol size distributions over the Mediterranean city of Barcelona, NE Spain

2012 ◽  
Vol 12 (7) ◽  
pp. 16457-16492 ◽  
Author(s):  
M. Dall'Osto ◽  
D.C.S. Beddows ◽  
J. Pey ◽  
S. Rodriguez ◽  
A. Alastuey ◽  
...  
Keyword(s):  
Particle Number ◽  
Number Concentration ◽  
Aerosol Size Distribution ◽  
Time Variability ◽  
Small Contribution ◽  
Particle Number Concentration ◽  
Size Distributions ◽  
Total Particle Number ◽  
Total Particle ◽  
One Year

Abstract. Differential mobility particle sizer (DMPS) aerosol concentrations (N13–800) were collected over a one-year-period (2004) at an urban background site in Barcelona, North-Eastern Spain. Quantitative contributions to particle number concentrations of the nucleation (33–38%), Aitken (39–49%) and accumulation mode (18–22%) were estimated. We examined the source and time variability of atmospheric aerosol particles by using both K-means clustering and Positive Matrix Factorization (PMF) analysis. Performing clustering analysis on hourly size distributions, nine K-means DMPS clusters were identified and, by directional association, diurnal variation and relationship to meteorological and pollution variables, four typical aerosol size distribution scenarios were identified: traffic (69% of the time), dilution (15% of the time), summer background conditions (4% of the time) and regional pollution (12% of the time). According to the results of PMF, vehicle exhausts are estimated to contribute at least to 62–66% of the total particle number concentration, with a slightly higher proportion distributed towards the nucleation mode (34%) relative to the Aitken mode (28–32%). Photochemically induced nucleation particles make only a small contribution to the total particle number concentration (2–3% of the total), although only particles larger than 13 nm were considered in this study. Overall the combination of the two statistical methods is successful at separating components and quantifying relative contributions to the particle number population.

172Coronary 18F-sodium fluoride uptake predicts progression of coronary arterial calcification

2019 ◽  
Vol 40 (Supplement_1) ◽  
Author(s):  
M Doris ◽  
A J Moss ◽  
J P M Andrews ◽  
M Williams ◽  
E J R Van Beek ◽  
...  
Keyword(s):  
Calcium Score ◽  
Coronary Calcification ◽  
Average Density ◽  
Agatston Score ◽  
Rapid Progression ◽  
Calcium Scoring ◽  
Total Calcium ◽  
Pet Ct ◽  
One Year ◽  
The Relationship

Abstract Background Combined positron emission tomography and computed tomography (PET-CT) using 18F-sodium fluoride (18F-NaF) to detect microcalcification provides the opportunity to gain important insights into disease activity in coronary atherosclerosis. However, the relationship between 18F-NaF uptake and progression of coronary calcification has not been determined. Purpose To determine the relationship between 18F-NaF uptake and progression of coronary calcification in patients with clinically stable coronary artery disease (CAD). Methods Patients with established, multivessel CAD underwent 18F-NaF PET-CT and CT coronary calcium scoring at baseline, with repeat CT calcium scoring at one year. Coronary arterial PET uptake was analysed qualitatively and semi-quantitatively in diseased vessels by measuring maximum tissue-to-background ratio (TBRmax) – defined as the maximum standardised uptake value in a plaque divided by mean blood pool activity measured in the right atrium. Coronary calcification was quantified by measuring calcium mass, volume, average calcium density and total Agatston score (AU). Results In total, 185 patients underwent baseline and repeat imaging (median age 66 years, 80% men), and 118 (64%) had increased 18F-NaF uptake in at least one vessel. Median total calcium score, volume, mass and average density were higher in patients with compared to those without increased 18F-NaF uptake (Table 1). At one year, patients with evidence of increased 18F-NaF uptake demonstrated more rapid progression of coronary calcification (97 [39–166] AU) versus those without uptake (35 [7–93] AU; p<0.0001). Amongst 18F-NaF-positive patients, the calcium score increased only in coronary segments with 18F-NaF uptake (baseline 90.5 [27.5–202] AU versus one year 135.5 [59.3–281.8] AU; p<0.0001) and not in 18F-NaF-negative segments (baseline 44.5 [16–110.5] AU versus one year 46.5 [18.25–114] AU; p=0.446). There was a moderate correlation between TBRmax and change in total calcium score, volume and mass at 1 year (Spearman's Rho = 0.37, 0.38, 0.46 respectively; p<0.0001 for all). Coronary calcification at baseline in PET-negative and PET-positive patients All patients (n=185) 18F-NaF Positive (n=118) 18F-NaF Negative (n=67) P value Agatston Score (AU) 381 [107–892] 541 [245–1130] 136 [55–361] p<0.0001 Calcium Volume (mm3) 358 [131–787] 506 [251–1014] 131 [64–343] p<0.0001 Calcium Mass (mg) 71 [23–155] 100 [48–222] 24 [11–69] p<0.0001 Average Density (mg/mm3) 0.19 [0.17–0.22] 0.20 [0.18–0.23] 0.18 [0.16–0.20] p<0.0001 Conclusions Coronary 18F-NaF uptake identifies both patients and individual coronary segments with greater disease and more rapid progression of coronary calcification over one year. Acknowledgement/Funding AstraZeneca (unrestricted educational grant). British Heart Foundation (CH/09/002, RE/13/3/30183, FS/17/79/33226) Wellcome Trust (WT103782AIA).

Control of Amsinckia spp. by the pastures of north-western Victoria

1965 ◽  
Vol 5 (19) ◽  
pp. 500
Author(s):  
DJ Connor
Keyword(s):  
Seed Production ◽  
Subterranean Clover ◽  
Barrel Medic ◽  
Limited Application ◽  
One Year ◽  
The One ◽  
Western Victoria ◽  
Establishment Phase ◽  
North Western ◽  
Very High

Amsinckia is a serious weed in the wheat growing areas of north-western Victoria. It is successful in the inter-crop pastures, based upon barrel medic, because it grows faster than barrel medic in the cooler months of May to August. In addition, the rapid growth in height associated with the change from rosette to elongating phases ensures a height advantage over the pasture species when the flush of pasture growth does commence. Seed production by each Amsinckia plant is very high, and for this reason any competitive restriction obtained in one year is not necessarily reflected in the establishment phase of the next. Subterranean clover c.v. Clare is more competitive than barrel medic and was able to eliminate Amsinckia from the sward in two years. However it has only limited application in the pastures of north-western Victoria. A mowing treatment was carried out at the commencement of Amsinckia flowering, for this coincides with the beginning of rapid pasture growth. Regrowth produced a reversal of height relationships within the pasture and enabled barrel medic to shade Amsinckia BJ this treatment growth and seed production of Amsinckia were reduced by 99 per cent within the one season.

More than just the animals: opportunities and costs of reintroducing threatened black-footed rock-wallabies to remote Indigenous land

2018 ◽  
Vol 24 (4) ◽  
pp. 388 ◽  
Author(s):  
Luke Ireland ◽  
Magdalena Zabek ◽  
Carolina Galindez-Silva ◽  
Sara Weir ◽  
Rebecca West ◽  
...  
Keyword(s):  
Threatened Species ◽  
Large Scale ◽  
Captive Breeding ◽  
Fire Management ◽  
South Australia ◽  
Project Cost ◽  
One Year ◽  
Cross Fostering ◽  
North Western ◽  
Indigenous Land

Conservation activities, including translocations of threatened species, are increasingly important priorities for conserving biodiversity and culture on Indigenous-managed lands, which occupy over 20% of the Australian landmass. In the Anangu Pitjantjatjara Yankunytjatjara (APY) Lands of north-western South Australia, the Warru Recovery Team reintroduced the threatened black-footed rock-wallaby (warru) to Wamitjara in May 2018. We outline the unique planning and logistical issues inherent in securing support and involvement of Traditional Owners and Indigenous rangers for predator, weed and fire management, cross-fostering, captive breeding, monitoring and translocation of the rock-wallabies. Altogether, the project cost AU$3.86 million (actual – AU$1.86 million, in kind – AU$2.00 million) over 10 years of preparation and one year of post-translocation monitoring. This consisted of AU$1.18 million for cross-fostering and captive breeding at Monarto Zoo and a further AU$0.55 million for the construction and maintenance of a fenced exclosure in the APY Lands. It is estimated that AU$0.51 million of the total costs were directly attributed to working remote and Indigenous-owned land, with most of the remaining costs typical of other reintroduction programs. Large-scale reintroduction opportunities on Indigenous-managed land can provide considerable conservation outcomes as well as delivering cultural objectives and supporting employment.

scholarly journals Field Survey of Tsunami Heights and Runups Following the 22 December 2018 Anak Krakatau Volcano Tsunami, Indonesia

2020 ◽  
Vol 177 (10) ◽  
pp. 4577-4595 ◽  
Author(s):  
Mohammad Heidarzadeh ◽  
Purna Sulastya Putra ◽  
Septriono Hari Nugroho ◽  
Doud Ben Zubair Rashid
Keyword(s):  
Rare Event ◽  
Tsunami Height ◽  
Field Surveys ◽  
Tsunami Runup ◽  
Tsunami Risk ◽  
Western Shore ◽  
Wave Heights ◽  
One Year ◽  
Instrumental Records ◽  
Krakatau Volcano

Abstract The 22 December 2018 Anak Karakatau tsunami in Indonesia was a rare event in that few instrumental records existed of tsunamis generated by volcanic sources before this event. The tsunami, which left a death toll of 437, is of global importance as it provides opportunities to develop knowledge on generation, propagation and coastal effects of volcanic tsunamis. Here, we report results of field surveys along the coast of the Sunda Strait, Indonesia to study tsunami wave heights and coastal damage. We surveyed 29 locations and measured ranges of tsunami runup from 0.9 to 5.2 m, tsunami heights from 1.4 to 6.3 m, flow depths from 0.2 m to 3.0 m and inundation distances from 18 to 212 m. The largest tsunami heights and concentration of damage and fatalities occurred on the western shore of Java from Tanjung Lesung to Sumur. The largest cluster of fatalities occurred at Tanjung Lesung, where more than 50 people died while attending an outdoor music being held at the shoreline. The tsunami runup and tsunami height in Tanjung Lesung were 4.0 and 2.9–3.8 m, respectively. We believe this tragedy could have been avoided if the event organizers were more aware of the hazard posed by the Anak Krakatau volcano, as it had been actively erupting for several months prior to the tsunami, and simply moved the concert stage 100 m inland. Many of the locations surveyed demonstrated a similar pattern where the majority of casualties and destruction occurred within 100 m of the coast; in several locations, lives were saved where buildings were located at least this distance inland. The significant damage and numerous deaths which occurred in Sumur, despite the moderate tsunami height of 2.3–2.5 m, can be attributed to the extremely low-lying coastal land there. Flow depth in Sumur was 0.9–2.0 m. During our field surveys, nearly one year after the event, we noted that some of the damaged buildings were being rebuilt in the same locations just 10–30 m from the shoreline. We question this practice since the new buildings could be at the same tsunami risk as those damaged in the 2018 event.

The effect of temperature on the field softening of hard seed of Stylosanthes humilis and S. hamata in a dry monsoonal climate

1982 ◽  
Vol 33 (1) ◽  
pp. 75 ◽  
Author(s):  
GM McKeon ◽  
JJ Mott
Keyword(s):  
Management Practices ◽  
Soil Surface ◽  
Field Studies ◽  
Effect Of Temperature ◽  
Maximum Temperature ◽  
Hard Seed ◽  
Surface Temperatures ◽  
Stylosanthes Humilis ◽  
One Year ◽  
Field And Laboratory Conditions

The changes in hard-seed content in pastures of Stylosanthes humilis and S. hamata cv. Verano were studied at Katherine, N.T. Both field studies and laboratory ovens with diurnal temperature changes showed that maximum soil surface temperatures greater than 50-55�C were required to produce substantial softening of hard seed. The rate of softening increased with higher maximum temperature. At Katherine, only the September-November period (late dry season) was likely to produce soil surface temperatures high enough for softening in naturally occurring seed populations. S. hamata did not soften to the same extent as S. humilis under both field and laboratory conditions. In established pastures only 35 % of S. hamata seed softened in one year, compared with 60-80% in S. humilis. Management practices may be required to improve seedling regeneration or establishment of new pastures in S. hamata.

Predicting the ecological impact of cane toads (Bufo marinus) on threatened camaenid land snails in north-western Australia

2009 ◽  
Vol 36 (6) ◽  
pp. 533 ◽  
Author(s):  
David Pearson ◽  
Matthew Greenlees ◽  
Georgia Ward-Fear ◽  
Richard Shine
Keyword(s):  
Western Australia ◽  
Life Histories ◽  
Activity Patterns ◽  
Ecological Impact ◽  
Bufo Marinus ◽  
Land Snails ◽  
Field Surveys ◽  
Habitat Overlap ◽  
Litoria Caerulea ◽  
North Western

The spread of cane toads (Bufo marinus) through north-western Australia may threaten populations of endemic camaenid land snails because these snails exhibit restricted geographic distributions, low vagility and ‘slow’ life-histories. We conducted laboratory trials to determine whether toads would consume camaenids if they encountered them, and conducted field surveys to evaluate the likelihood of such encounters (on the basis of habitat overlap). In laboratory trials with 13 camaenid species, cane toads were more likely to consume camaenids than were two species of native frogs that we tested (Cyclorana australis, Litoria caerulea). However, field surveys suggested that many camaenids are active on vertical surfaces in limestone outcrops, and cane toads rarely venture into these habitats. Although the preferred habitats and activity patterns of camaenids thus reduce their vulnerability to cane toads, we recommend regular surveys of toad and snail numbers to monitor toad impacts. Given the restricted distributions of threatened saxicoline camaenid species in the Kimberley, localised management of grazing stock and fire is feasible to maintain vine-thicket vegetation cover and snail populations, as well as reducing open habitats favoured by toads.

scholarly journals The influence of depth on the Mediterranean reef fish assemblage revealed by the new video on underwater scooter method

2020 ◽  
Vol 61 (2) ◽  
pp. 145-162
Author(s):  
Igor Glavičić ◽  
Marcelo Kovačić ◽  
Dejan Paliska ◽  
Dani Laslo
Keyword(s):  
Reef Fish ◽  
Fish Assemblage ◽  
Environmental Variables ◽  
Fish Assemblages ◽  
Average Density ◽  
Depth Range ◽  
Fish Assemblage Structure ◽  
Visual Census ◽  
Reef Fish Assemblage ◽  
Significant Difference

The new video on underwater scooter method in combination with rebreather diving techniques was introduced and applied for visual census of fish assemblages. The presently applied method facilitates deeper visual census studies below 40 m, where they have rarely been done before due to the increasing research challenges with depth. The video on underwater scooter method is also expected to be less disturbing and faster compared to swimming divers. The method was applied in visual census study of fish assemblages from 8 to 50 m depth conducted at two locations in the east Adriatic using 102 video transects. The environmental variables contributing to the variation of the reef fish community in the depth range of the infralittoral and upper circalittoral bottoms were also recorded. Thirty-one fish species were recorded on transects and 10.3% of all individuals were not identified to the species level. The average density on transects was 0.8 individuals/m², with C. chromis, C. julis and G. auratus being both the most abundant and the most frequent species. Three environmental variables, depth, bottom with zoocover and eastern orientation of the coast, were identified as highly significant for species occurrence. Abundance and species richness of fish assemblages showed no significant variation with depths, inclinations, orientations and sites. A significant difference in the fish assemblage structure was found among orientations, depths and inclinations with the gradient change of species composition with increasing depth and with increasing inclination.

scholarly journals Phenology, Seasonal Abundance, and Host-Plant Association of Spittlebugs (Hemiptera: Aphrophoridae) in Vineyards of Northwestern Italy

Insects ◽  
2021 ◽  
Vol 12 (11) ◽  
pp. 1012
Author(s):  
Nicola Bodino ◽  
Stefano Demichelis ◽  
Anna Simonetto ◽  
Stefania Volani ◽  
Matteo Alessandro Saladini ◽  
...  
Keyword(s):  
Host Plant ◽  
Late Summer ◽  
Common Species ◽  
Seasonal Abundance ◽  
Cultivated Plants ◽  
Plant Association ◽  
Egg Hatching ◽  
Field Surveys ◽  
One Year ◽  
Cover Up

Spittlebugs (Hemiptera: Aphrophoridae) are the vectors of the bacterium Xylella fastidiosa (Xf) in Europe. Xf may cause severe epidemics in cultivated plants, including grapevines. To assess the threat represented by the bacterium to grapevines, detailed information on the vectors’ phenology, density, and ecology in vineyards is needed. The aim of the present work was to describe spittlebug diversity, phenology, and host-plant association in the vineyard agroecosystem. Two separate field surveys of nymphal and adult spittlebug populations, i.e., a two-year survey of a single site and a one-year survey of three sites, were performed in vineyards of northwestern Italy in three consecutive years. Philaenus spumarius was the most common species, reaching average nymph densities on herbaceous cover up to 60–130 nymphs/m2. Adults were sampled on grapevines from May to September, with a peak in June (up to 0.43 insects/sweep). Herbaceous cover was colonized after egg hatching and in late summer for oviposition, while wild woody hosts represented a refuge during summer. The results show that spittlebugs can reach high population levels in vineyards, at least in the areas where the ground is covered by herbaceous plants for the whole season and the use of insecticides is moderate. The extended presence of P. spumarius adults on grapevines represents a serious risk factor for the spread of Xf. The scenarios of Xf establishment in vineyards in northwestern Italy and Europe are discussed in relation to the abundance, phenology, and plant association of spittlebugs.

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