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Factors driving Adélie penguin chick size, mass and condition at colonies of different sizes in the Southern Ross Sea
Full text linkBody size, mass and condition can affect an organism’s ability to cope with variation in resource availability or metabolic demand, particularly as juveniles reach independence. It follows that changes to parental provisioning efficiency (size and frequency of meals) through intraspecific competition or environmental conditions that affect prey availability may affect chick size, mass and condition and ultimately post-fledging survival. We examined how Adélie penguin chick size, mass and condition varied among colonies of different sizes on Ross Island during a 15 yr period of high environmental variability and varying intraspecific competition. Aiding the study was a natural experiment in which the presence of 2 giant icebergs midway through the study abnormally increased sea ice concentration (SIC), altering adults’ access to food. Concurrently, the colonies were rapidly increasing in size; based on previous work, this indicated increased trophic competition near colonies, a trend likely indicating a changing food web in the greater region. Results showed that increased amounts of sea ice, which reduced the ability of adults to access food, had a negative effect on the size and mass of chicks. However, a greater proportion of fish (vs. krill) in the diet had a positive effect on chick size. Moreover, in some cases, increased intraspecific competition may be a more important driver of provisioning rate and chick size than abiotic factors, with chicks showing the effects of reduced food delivery at larger colonies. Understanding these patterns will allow better understanding of how factors such as climate change and altered food webs may affect Adélie penguin populations.Keywords: Intraspecific competition, Chick growth, Diet variability, Adélie penguin, Provisioning efficiencyKeywords: Intraspecific competition, Chick growth, Diet variability, Adélie penguin, Provisioning efficienc
Water transport properties of vine and tree stems in a tropical deciduous forest
No full textExcised stem segments of vines had higher specific hydraulic conductivies (flow rate per pressure gradient per stem transverse area) than did trees during the dry season in a deciduous forest in Jalisco, Mexico. Vine species averaged from 2.7 to 203 x 10-3 m2 MPa-1 s-1 and tree species from 0.8 to 5.1 x 10-3 m2 MPa-1 s-1. Only three of the 20 species retain their leaves during part or all of the dry season, and these included the vine and the tree with the lowest conductivities within their growth forms. An index of the mean diameter of the six widest vessels per sample was positively and significantly correlated with specific conductivity for the vines but not the trees. Stem density (g cm-3, dry weight/wet volume) was not correlated with either specific conductivity or vessel diameter index for vines or trees.Keywords: self-supported, specific conductivity, Chamela, vine, liana, MexicoKeywords: self-supported, specific conductivity, Chamela, vine, liana, Mexic
Plate 12.jpg
No full textThe Santa Barbara-Montecito and Goleta basins are structurally
continuous fault-controlled Pleistocene basins containing
up to 3000 feet (925 m) of marine Pleistocene Santa Barbara Formation
which were deposited on previously deformed Sisquoc and older
strata. Structures subcropping against the unconformity at the
base of the Santa Barbara Formation show that pre-basin deformation
was mainly by folding. In addition, high-angle reverse
faulting occurred along the Cameros, Goleta, and Modoc faults prior
to Santa Barbara deposition in the Goleta basin. These are the
oldest faults in the study area.
Deposition of the Santa Barbara Formation began less than 1.2
Ma ago. Post-Santa Barbara (post-basin) deformation includes
disharmonic folding of incompetent Miocene strata above broad
folds in competent Oligocene strata, as displayed in the Elwood oil
field and La Goleta gas field, and reverse faulting along several
south-dipping faults of large displacement. The More Ranch fault,
which juxtaposes Sisquoc and older strata against the Santa
Barbara and Pico(?) Formations, displaces a 40,000 year old
marine terrace, forms a north-facing eroded fault scarp, and marks
the southern edge of the Goleta basin. The fault dips more than
80° south and displays up to a maximum of 2000 feet (610 m)
vertical separation.
The fault in the area with the largest amount of vertical
separation, is the Coal Oil Point fault of post-Sisquoc age. This
fault fails to reach the surface even though vertical separation
of the Oligocene Vaqueros Formation is as great as 5400 feet (1650
m). Comparison with other faults in the area suggests that this
fault belongs to the set of south-dipping, east-trending, Quaternary
reverse faults that are characteristic of the coastal basins
adjacent to the central Santa Ynez Mountains.
All post-basin faults disrupt late Pleistocene strata and are
potentially active. Other post-basin faults include the Mesa
fault, which may link the More Ranch and Rincon Creek faults, the
Lavigia fault which cuts older alluvium, and the San Jose fault
which forms a north-facing scarp in late-Pleistocene fanglomerate.
Distribution of aftershocks and focal mechanism solutions of
the 1978 Santa Barbara earthquake suggest a gently north-dipping
fault plane which would be unrelated to any of the faults exposed
at the surface in the study area. However, the linear pattern of
aftershock epicenters is parallel to the Mesa and Mission Ridge-
Arroyo Parida faults; if the alternate south-dipping nodal plane
is the correct solution then the earthquake could have originated
on a member of the south-dipping fault set
Quantification of Complex Polycyclic Aromatic Hydrocarbon Mixtures in Standard Reference Materials Using GC×GC/ToF-MS
Full text linkThis research is the first to quantify complex PAH mixtures in NIST SRMs using comprehensive two-dimensional gas chromatography coupled to time-of-flight mass spectrometry (GC×GC/ToF-MS), with and without extract cleanup, and reports previously unidentified PAH isomers in the NIST SRMs. We tested a novel, high orthogonality GC column combination (LC-50×NSP-35), as well as with a commonly used column combination (Rtx-5ms×Rxi-17) for the quantification of a complex mixture of 85 different PAHs, including parent (PAHs), alkyl- (MPAHs), nitro- (NPAHs), oxy- (OPAHs), thio- (SPAHs), bromo- (BrPAHs), and chloro-PAHs (ClPAHs) in extracts from two standard reference materials: NIST SRM1650b (diesel particulate matter), with cleanup and NIST SRM1975 (diesel particulate extract), with and without extract cleanup. The LC-50×NSP-35 column combination resulted in an average absolute percent difference of 33.8%, 62.2% and 30.8% compared to the NIST certified PAH concentrations for NIST SRM1650b, NIST SRM1975 with cleanup and NIST SRM1975 without cleanup, while the Rtx-5ms×Rxi-17 resulted in an absolute percent difference of 38.6%, 67.2% and 79.6% for NIST SRM1650b, NIST SRM1975 with cleanup and NIST SRM1975 without cleanup, respectively. This GC×GC/ToF-MS method increases the number of PAHs detected and quantified in complex environmental extracts using a single chromatographic run. Without clean-up, 7 additional compounds were detected and quantified in NIST SRM1975 using the LC-50×NSP-35 column combination. These results suggest that the use of the LC-50×NSP-35 column combination in GC×GC/ToF-MS not only results in better chromatographic resolution and greater orthogonality for the separation of complex PAH mixtures, but can also be used for the accurate quantification of complex PAH mixtures in environmental extracts without cleanup.Keywords: PAHs, Quantitation of POPs, Comprehensive Two-dimensional Gas Chromatography, ToF-MS, Complex Environmental SamplesKeywords: PAHs, Quantitation of POPs, Comprehensive Two-dimensional Gas Chromatography, ToF-MS, Complex Environmental Sample
Factors Affecting Consumer's Attitudes Towards Aquaculture
Full text linkAttitudes towards production processes increased their importance over food purchase decissions in recent years. This paper aims to test which factors mainly affects attitudes towards aquaculture. Factors are classified into three groups: demographic, situational, and personal and marketing infuences. Using consumer survey data, factor analysis techniques were used to obtain an attitude meassure from a set of scales. Diferent linear models and fit methods were performed with variables of the three groups of factors to test for significant effects over attitude scores. Significant effects were found with education, ocupation and income. Purchase and consumption place were also found to be significant causes of diferencies across attitudes. Finally Consumer involvement with food safety and sustainability and generic advertising credibility have shown significant effects over attitudes towards aquaculture.Keywords: Consumer attitudes, Food purchase decisions, Safety and sustainability beliefs, Market conditionants, Aquaculture, Advertising credibility, Fisheries EconomicsKeywords: Consumer attitudes, Food purchase decisions, Safety and sustainability beliefs, Market conditionants, Aquaculture, Advertising credibility, Fisheries Economic
Current Worldwide Contribution of Marine Fish to Human Welfare
Full text linkSome attempts have been made in the past to provide estimates of the value of global fisheries. For example, catch values from marine fisheries have been reported by the FAO (2008) and Sumaila et al. (2007). The World Bank (2008) estimated that current economic rent from the worlds fisheries is negative 50 billion a year. Here, we provide a more comprehensive estimate of the contribution of marine fish to human welfare, which is defined narrowly to mean the sum of worldwide (i) income to workers in the marine fishing sector; (ii) profits to fishing enterprises; and (iii) resource rent to citizens of the world, who, according to national and international laws and rules, are the owners of marine fish stocks. This definition means that our estimate of the contribution of marine fisheries to human welfare is conservative since it does not include all values. For example, the added value through the fish chain and non-market values are not counted. Still, our approach is a step forward towards determining more comprehensive estimates of the contribution of marine fisheries to human welfare. To carry out the objective of the paper, we relied on a diverse range of global fisheries databases created by the Sea Around Us (www.seaaroundus.org) and the Fisheries Economics Research Unit (www.feru.org). These include a global (i) catch database (Watson et al. 2005?); (ii) ex-vessel fish price database (Sumaila et al. 2007); (iii) subsidies database (Sumaila and Pauly, 2006); (iv) cost of fishing database (Lam et al., 2010); and (v) fisheries jobs database (Teh and Sumaila 2010).Keywords: Fisheries Economics, Fishery Management, Global Fisheries Contribution to National Economies: Management and Policy Options for Rebuildin
StillChristopherForestryNocturnalWaterCycle.pdf
No full textThe movement of moisture into, out-of, and within forest ecosystems is modulated
by feedbacks that stem from processes which couple plants, soil, and the atmosphere.
While an understanding of these processes has been gleaned from Eddy Covariance
techniques, the reliability of the method suffers at night because of weak turbulence.
During the summer of 2011, continuous profiles of the isotopic composition (i.e., δ¹⁸O
and δD) of water vapor and periodic measurements of soil, leaf, and precipitation pools
were measured in an open-canopy ponderosa pine forest in central Colorado to study
within-canopy nocturnal water cycling. The isotopic composition of the nocturnal water
vapor varies significantly based on the relative contributions of the three major
hydrological processes acting on the forest: dewfall, exchange of moisture between leaf
waters and canopy vapor, and periodic mixing between the canopy and background air.
Dewfall proved to be surprisingly common (~30% of the nights) and detectable on both
the surface and within the canopy through the isotopic measurements. While surface dew
could be observed using leaf wetness and soil moisture sensors, dew in the foliage was
only measurable through isotopic analysis of the vapor and often occurred even when no
dew accumulated on the surface. Nocturnal moisture cycling plays a critical role in water
availability in forest ecosystems through foliar absorption and transpiration, and
assessing these dynamics, as done here, is necessary for fully characterizing the
hydrological controls on terrestrial productivity.Keywords: dewfall, forest hydrology, water isotopes, nocturnal boundary layerKeywords: dewfall, forest hydrology, water isotopes, nocturnal boundary laye
Comparison of Area-averaged and Local Boiling Curves in Pool and Jet Impingement Boiling
Full text linkCharacterization of local boiling trends, in addition to the typically reported area-averaged trends, is essential for the robust design and implementation of phase change technologies to sensitive heat transfer applications such as electronics cooling. This paper compares local and area-averaged boiling curves during a phase change process using non-intrusive quantitative infrared thermal visualization to highlight the importance of considering the former in design of phase change cooling systems. As an illustration, both pool and jet impingement boiling modes of heat transfer from a heated silicon surface are considered. A thin-film serpentine heater that allows for a circumferentially uniform but radially non-uniform heat flux distribution on the surface is chosen as the heat source in order to assess the effect of spatial variations in imposed boundary condition on the local and area-averaged boiling curves.
Local convective heat fluxes are estimated from thermal maps using a control volume approach that accounts for axial conduction in the silicon substrate. Using the spatial information on surface temperatures and convective heat fluxes, local boiling curves are generated for different radial locations on the surface and compared with their corresponding area-averaged representations. As validation, it is shown that the net input electrical heat flux varies within 4 to 12 percent of the area-averaged results. Boiling curves averaged over regions of like imposed boundary condition are seen to provide a more realistic estimate of the local heat transfer conditions when compared with an area-averaged representation of the entire surface. Area-averaged thin-film sensor data are used to augment the heat transfer data by highlighting the differences in nucleation events on the surface in different regions.Keywords: Boiling, Jet impingement, Local boiling curves, Thin-film sensors, Infrared thermography, Probability distribution functionKeywords: Boiling, Jet impingement, Local boiling curves, Thin-film sensors, Infrared thermography, Probability distribution functio
Risk Assessment of the Mediterranean Seabass and Seabream industry in Greece: A Stochastic Simulation Approach Based on insurance Claims
Full text linkThe Mediterranean finfish aquaculture is strongly represented from the successful industrial development of the mass production of the Mediterranean seabass (Dicentrarchus labrax) and seabream (Spaurus aurata), with Greece as the major producer country, contributing with approximately 57% of the global farmed production of both species. Despite the difficulty to obtain information from the private and public sector about the aquaculture insurance claims, the analysis of insurance data is necessary to develop a risk management strategy of the industry. The aim of the present work is to identify the major risks affecting the seabass/seabream aquaculture by examining qualitative and quantitative insurance claims from the early developmental stage (mid-80s) up to the maturation of the Greek sector (2000). A risk assessment based on scenario quantification and Monte Carlo Simulation with the ZHA WORKS 4.2 QUANT software is used to reveal percentile statistics of 1 Year/Worst out of x Years aggregate loss and thus to "harden" the basis for decision taking. The use of the past insurance experience provides forecasting trends for risk avoidance in the future and contributes to a strategy development for the sustainability of the sector.Keywords: Aquaculture, Aquaculture and Risk, Fisheries EconomicsKeywords: Aquaculture, Aquaculture and Risk, Fisheries Economic
miranda garciaThesis FINAL.pdf
No full textFlour aging is thought to occur naturally during storage of wheat flour. In soft-wheat it is hypothesized that aging may increase water absorption properties of the flour. The aim of this study was to determine if the absorption capacity of flour changes as a response to flour aging. Absorption was monitored by Solvent Retention Capacity (SRC). SRC consists of four tests, each using a different solvent: water, and aqueous solutions of 5% (w/w) sodium carbonate, 50% (w/w) sucrose, and 5% (w/w) lactic acid. Each solvent emphasizes specific polymeric components of flour, respectively: all components; damaged starch; arabinoxylan (fiber) and gliadin; and glutenin. Grain from 4 soft-wheat varieties was milled into flour 0, 3, 6, 12, and 24 weeks after harvest. At each milling date SRC was performed on the stored flour on specified days over a 2 month period. The major differences observed were between varieties. Except for lactic acid SRC, SRC values for 2 of the 4 wheat varieties, Tubbs and Goetze were significantly higher (p ≤ 0.05) than SRC values for the other 2 varieties, Skiles and Bobtail. These differences were greater in magnitude than differences associated with storage and aging and were generally consistent across all weeks after harvest and days after milling. Water and sucrose SRCs showed small but significant increases (p ≤ 0.05) across the storage period. Mean water SRC across all 4 varieties increased from a minimum of 52.5% to a final value at 6 months of 53.3%. Mean sucrose SRC across all 4 varieties increased from a minimum of 72.1% to a final value at 6 months of 73.1%. This supported the original hypothesis of increased absorption during aging. Sodium carbonate and lactic acid SRCs showed small but significant decreases (p ≤ 0.05) across the storage period, partially refuting the original hypothesis. Sodium carbonate SRC was significantly higher at Week 0 Day 0 (p ≤ 0.01) compared to all other days. Mean lactic acid
SRC across all varieties decreased from a maximum of 110.5% to a final value at 6 months of 107.5%. These data indicate that except for carbonate SRC at Week 0 Day 0, SRC analyses could be performed immediately after milling on freshly harvested grain and provide valid comparisons among wheat genotypes. However, the modulating effect of storage and aging is important to note, especially the small increases in water and sucrose SRCs, the decline in carbonate SRC after grain storage and flour aging, and the overall decline in lactic acid SRC that may indicate a decline in gluten performance. Knowledge of the impact of aging on flour functionality predictions is vital in a wheat breeding program, where high throughput in short timeframes is an unavoidable operational demand. This means that testing freshly milled flour from freshly harvested grain is often a necessity. These data suggest that this is valid at least for water and sucrose SRCs in soft white wheat. Sequencing the testing so that carbonate SRC was done last may be an operational strategy to compensate for the observed overestimation of this parameter when testing flour freshly milled from freshly harvested grain.Keywords: storage, flour, wheat, Solvent Retention Capacity (SRC