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1.
Stephen A. Wainwright 《Die Naturwissenschaften》1970,57(7):321-326
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Laursen K White TJ Cresswell DJ Wainwright PJ Barton JR 《Journal of environmental management》2006,80(3):208-213
The geographical limitations of Singapore, its restricted natural resources and voluminous municipal and industrial waste streams, make environmental management a major challenge for the island state. In an attempt to find ways to reduce importation of raw materials and the waste sent to landfill, light weight aggregates were produced from marine clay and a CaF(2)-rich semiconductor industry sludge. Aggregates were produced in a bench-scale rotary kiln with three clay/sludge loadings (90/10, 70/30 and 50/50%). All three mixtures showed good bloating behavior during firing and the ceramic pellets (1-1.5cm diameter) had densities well below that required for light-weight aggregates. In the initial tests, the pore sizes of the aggregates were in general too large resulting in high water absorption. Comparisons between the composition of the two waste products and the aggregates showed a significant loss of fluorine (40-60%) during processing; a problem which may require flue gas treatment. Leach testing showed that the formed aggregates would not pose a human or environmental hazard in terms of fluorine mobilization. 相似文献
4.
L. A. Ferry-Graham P. C. Wainwright M. W. Westneat D. R. Bellwood 《Marine Biology》2002,141(5):819-830
Teleost fishes capture prey using ram, suction, and biting behaviors. The relative use of these behaviors in feeding on midwater
prey is well studied, but few attempts have been made to determine how benthic prey are captured. This issue was addressed
in the wrasses (Labridae), a trophically diverse lineage of marine reef fishes that feed extensively on prey that take refuge
in the benthos. Most species possess strong jaws with stout conical teeth that appear well-suited to gripping prey. Mechanisms
of prey capture were evaluated in five species encompassing a diversity of feeding ecologies: Choerodon anchorago (Bloch, 1791), Coris gaimard (Quoy and Gaimard, 1824), Hologymnosus doliatus (Lacepède, 1801), Novaculichthys taeniourus (Lacepède, 1801) and Oxycheilinus digrammus (Lacepède, 1801). Prey capture sequences were filmed with high-speed video at the Lizard Island Field Station (14°40′S, 145°28′E)
during April and May 1998. Recordings were made of feeding on pieces of prawn suspended in the midwater and similar pieces
of prawn held in a clip that was fixed to the substratum. Variation was quantified among species and between prey types for
kinematic variables describing the magnitude and timing of jaw, hyoid, and head motion. Species differed in prey capture kinematics
with mean values of most variables ranging between two and four-fold among species and angular velocity of the opening jaw
differing seven-fold. The kinematics of attached prey feeding could be differentiated from that of midwater captures on the
basis of faster angular velocities of the jaws and smaller movements of cranial structures which were of shorter duration.
All five species used ram and suction in combination during the capture of midwater prey. Surprisingly, ram and suction also
dominated feedings on attached prey, with only one species making greater use of biting than suction to remove attached prey.
These data suggest an important role for suction in the capture of benthic prey by wrasses. Trade-offs in skull design associated
with suction and biting may be particularly relevant to understanding the evolution of feeding mechanisms in this group.
Published online: 11 July 2002 相似文献
5.
Yazvenko SB McDonald TL Blokhin SA Johnson SR Melton HR Newcomer MW Nielson R Wainwright PW 《Environmental monitoring and assessment》2007,134(1-3):93-106
Exxon Neftegas Limited, as operator of the Sakhalin-1 consortium, is developing oil and gas reserves on the continental shelf
off northeast Sakhalin Island, Russia. DalMorNefteGeofizika (DMNG) on behalf of the Sakhalin-1 consortium conducted a 3-D
seismic survey of the Odoptu license area during 17 August–9 September 2001. A portion of the primary feeding area of the
endangered western gray whale (Eschrichtius robustus) is located in the vicinity of the seismic survey. This paper presents data to assess whether western gray whale bottom feeding
activity, as indicated by visible mud plumes, was affected by seismic operations. The mitigation and monitoring program associated
with the seismic survey included aerial surveys during 19 July–19 November 2001. These aerial surveys documented the local
and regional distribution, abundance, and bottom feeding activity of western gray whales. Data on gray whale feeding activity
before, during and after the seismic survey were collected, with the whales assumed to be feeding on the benthos if mud plumes
were observed on the surface. The data were used to assess the influence of seismic survey and other factors (including environmental)
on feeding activity of western gray whales. A stepwise multiple regression analysis failed to find a statistically significant
effect (α = 0.05) of the seismic survey on frequency of occurrence of mud plumes of western gray whales used as a proxy to evaluate
bottom feeding activity in Piltun feeding area. The regression indicated that transect number (a proxy for water depth, related
to distance from shore) and swell height (a proxy for sea state) were the only variables that had a significant effect on
frequency of whale mud plumes. It is concluded that the 2001 seismic survey had no measurable effect (α = 0.05) on bottom feeding activity of western gray whales off Sakhalin Island.
M.W. Newcomer, deceased 相似文献
6.
The mechanism of prey capture in two syngnathid fishes, the lined seahorse Hippocampus erectus (Perry) and the dusky pipefish Syngnathus floridae (Jordan and Gilbert), is described based on anatomical observations and high-speed video recordings (200 and 400 images s−1) of feeding events by four seahorses and three pipefish. The fish were collected near Turkey Point, Florida, U.S.A., in January
1994 to March 1995. The dominant features of the morphology of these and many other syngnathiform fishes include extreme elongation
of the suspensorium and neurocranium with a small mouth located at the anterior tip of the head. In the seahorse, a preparatory
phase of prey capture consisted of slow ventral head flexion. This was followed by rapid elevation of the head and snout as
the prey was drawn into the mouth by suction. Both H. erectus and S. floridae capture prey rapidly, with peak head excursions and mouth opening occurring within 5 to 7 ms of the onset of the strike.
There was no upper jaw protrusion. In both species the time to recovery of the cranium and hyoid apparatus to resting positions
was highly variable but took at least 500 ms. Manipulations of freshly dead specimens indicated a biomechanical linkage between
head elevation and hyoid depression. However, the predictions of a previously proposed four-bar linkage model that couples
hyoid depression to head elevation were not fully supported by kinematic data from one seahorse, suggesting that additional
linkages act during the expansive phase of prey capture. These species exhibit the generalized kinematic pattern of prey capture
in bony fishes, with head elevation, hyoid depression and mouth opening occurring almost simultaneously. The derived morphology
results in a unique feeding behav‐ior, in which prey are captured during a sudden up-swing of the head, which brings the mouth
to the prey. Suction is used to draw the prey into the buccal cavity.
Received: 4 August 1996 / Accepted: 27 August 1996 相似文献
7.
There has been increasing recognition within systematic conservation planning of the need to include social data alongside
biophysical assessments. However, in the approaches to identify potential conservation sites, there remains much room for
improvement in the treatment of social data. In particular, few rigorous methods to account for the diversity of less-easily
quantifiable social attributes that influence the implementation success of conservation sites (such as willingness to conserve)
have been developed. We use a case-study analysis of private conservation areas within the Little Karoo, South Africa, as
a practical example of the importance of incorporating social data into the process of selecting potential conservation sites
to improve their implementation likelihood. We draw on extensive data on the social attributes of our case study obtained
from a combination of survey questionnaires and semi-structured interviews. We discuss the need to determine the social attributes
that are important for achieving the chosen implementation strategy by offering four tested examples of important social attributes
in the Little Karoo: the willingness of landowners to take part in a stewardship arrangement, their willingness to conserve,
their capacity to conserve, and the social capital among private conservation area owners. We then discuss the process of
using an implementation likelihood ratio (derived from a combined measure of the social attributes) to assist the choice of
potential conservation sites. We conclude by summarizing our discussion into a simple conceptual framework for identifying
biophysically-valuable sites which possess a high likelihood that the desired implementation strategy will be realized on
them. 相似文献
8.
PW Kok HY Ong MK Wong WK Au KT Tan WH Phoon CN Ong 《Environmental monitoring and assessment》1997,44(1-3):425-431
Occupational exposure to benzene was measured in two gasoline marketing terminals and five major refineries in Singapore. A total of 280 workers were monitored over two years. This assessment was carried out with two primary objectives: (1) To find out the extent of occupational exposure to benzene in the petroleum industry in Singapore, (2) To identify suitable biomarkers for monitoring of low levels of benzene exposure. The exposure was measured in five different categories of petroleum and petrochemical workers, i.e., truck drivers, despatch assistant, process operators, oil movements operators and laboratory technicians. The results revealed wide variations in exposure, from 0.01 to 13.6 ppm for personal time weighted average (TWA) exposure over the whole workshift. The exposure of truck drivers appeared to be the highest, with geometric mean (GM) of 1.98 ppm (ranged from 0.25 to 13.6 ppm). The average benzene exposure for process operators was relative low with a GM of 0.04 ppm. Lowest benzene exposure was found in the laboratory technicians, with a GM of 0.02 ppm. As cigarette smoking is known to affect metabolism of benzene, data analyses on the relationships with environmental exposure were conducted only on the 190 nonsmokers. The results showed that urinary trans, trans-muconic acid (ttMA), unmetabolized benzene in urine (UBZ) and benzene in blood (BBZ) were better biomarkers for low level benzene exposure as compared to urinary phenolic metabolites in urine, such as hydroquinone, phenol and catechol. 相似文献
9.
Yazvenko SB McDonald TL Blokhin SA Johnson SR Meier SK Melton HR Newcomer MW Nielson RM Vladimirov VL Wainwright PW 《Environmental monitoring and assessment》2007,134(1-3):45-73
Exxon Neftegas Limited, operator of the Sakhalin-1 consortium, is developing oil and gas reserves on the continental shelf
off northeast Sakhalin Island, Russia. DalMorNefteGeofizika (DMNG), on behalf of the Sakhalin-1 consortium, conducted a 3-D
seismic survey of the Odoptu license area during 17 August–9 September 2001. A portion of the primary known feeding area of
the endangered western gray whale (Eschrichtius robustus) is located adjacent to the seismic block. The data presented here were collected as part of daily monitoring to determine
if there was any measurable effect of the seismic survey on the distribution and abundance of western gray whales. Mitigation
and monitoring program included aerial surveys conducted between 19 July and 19 November using the methodology outlined by
the Southern California High Energy Seismic Survey team (HESS). These surveys provided documentation of the distribution,
abundance and bottom feeding activity of western gray whales in relation to seismic survey sounds. From an operations perspective,
the aerial surveys provided near real-time data on the location of whales in and outside the feeding area, and documented
whether whales were displaced out of an area normally used as feeding habitat. The objectives of this study were to assess
(a) temporal changes in the distribution and abundance of gray whales in relation to seismic survey, and (b) the influence
of seismic survey, environmental factors, and other variables on the distribution and abundance of gray whales within their
preferred feeding area adjacent to Piltun Bay. Multiple regression analysis revealed a limited redistribution of gray whales
southward within the Piltun feeding area when the seismic survey was fully operational. A total of five environmental and
other variables unrelated to seismic survey (date and proxies of depth, sea state and visibility) and one seismic survey-related
variable (seg3d, i.e., received sound energy accumulated over 3 days) had statistically significant effects on the distribution and abundance
of gray whales. The distribution of two to four gray whales observed on the surface (i.e., about five to ten whales in total)
has likely been affected by the seismic survey. However, the total number of gray whales observed within the Piltun feeding
area remained stable during the seismic survey.
M. W. Newcomer, Deceased. 相似文献
10.
内分泌干扰物(EDCs)在环境和饮用水中的存在已经引起相关机构越来越大的关注.这些化合物通常在很低的浓度就对人类和野生动物产生生理影响. 相似文献