Annual Life Cycle and Production of the Chaetognath Sagitta elegans in Bedford Basin, Nova Scotia

1973 ◽  
Vol 30 (3) ◽  
pp. 333-344 ◽  
Author(s):  
D. D. Sameoto
Keyword(s):  
Growth Rate ◽  
Life Cycle ◽  
Nova Scotia ◽  
Turnover Rate ◽  
Degree Days ◽  
Annual Life Cycle ◽  
Order Of Magnitude ◽  
Annual Turnover

In Bedford Basin, Nova Scotia, Sagitta elegans has two main generations per year, one in the spring and one in the fall. The biomass of S. elegans per 100 m3 of water was an order of magnitude greater in the Basin than that reported previously for St. Margaret’s Bay, N.S. The growth rate and the number of degree days needed to mature were similar to those found for S. elegans in St. Margaret’s Bay. Annual turnover rate for S. elegans in the Basin was 5.6 and yearly production was estimated at 27.0 kcal per year or 9.0% of the yearly copepod production. It was calculated that the species used 90.4 kcal per m2 per year in respiration. The percentage of the total yearly production of copepods consumed by S. elegans was estimated at 36%.

scholarly journals Sustainable Panels Made with Industrial and Agricultural Waste: Thermal and Environmental Critical Analysis of the Experimental Results

2021 ◽  
Vol 11 (2) ◽  
pp. 494
Author(s):  
Paola Ricciardi ◽  
Elisa Belloni ◽  
Francesca Merli ◽  
Cinzia Buratti
Keyword(s):  
Thermal Conductivity ◽  
Life Cycle ◽  
Rice Husk ◽  
Agricultural Waste ◽  
Embodied Energy ◽  
Waste Materials ◽  
Impact Reduction ◽  
Combined Solution ◽  
Order Of Magnitude ◽  
Recycled Waste

Recycled waste materials obtained from industrial and agricultural processes are becoming promising thermal and acoustic insulating solutions in building applications; their use can play an important role in the environmental impact reduction. The aim of the present paper is the evaluation of the thermal performance of recycled waste panels consisting of cork scraps, rice husk, coffee chaff, and end-life granulated tires, glued in different weight ratios and pressed. Six panels obtained from the mixing of these waste materials were fabricated and analyzed. In particular, the scope is the selection of the best compromise solutions from the thermal and environmental points of view. To this aim, thermal resistances were measured in laboratory and a Life Cycle Assessment (LCA) analysis was carried out for each panel; a cross-comparative examination was performed in order to optimize their properties and find the best panels solutions to be assembled in the future. Life Cycle Analysis was carried out in terms of primary Embodied Energy and Greenhouse Gas Emissions, considering a ‘‘cradle-to-gate” approach. The obtained thermal conductivities varied in the 0.055 to 0.135 W/mK range, in the same order of magnitude of many traditional systems. The best thermal results were obtained for the panels made of granulated cork, rice husk, and coffee chaff in this order. The rubber granulate showed higher values of the thermal conductivity (about 0.15 W/mK); a very interesting combined solution was the panel composed of cork (60%), rice husk (20%), and coffee chaff (20%), with a thermal conductivity of 0.08 W/mK and a Global Warming Potential of only 2.6 kg CO2eq/m2. Considering the Embodied Energy (CED), the best solution is a panel composed of 56% of cork and 44% of coffee chaff (minimum CED and thermal conductivity).

Temporal variation in the weight-size relationship of the mangrove crab Ucides cordatus L. (Decapoda: Ucididae) in relation to its life cycle phases

2014 ◽  
Vol 64 (4) ◽  
pp. 333-342 ◽  
Author(s):  
Marcos de Miranda Leão Leite ◽  
Cynthia Yuri Ogawa ◽  
Carla Ferreira Rezende ◽  
José Roberto Feitosa Silva
Keyword(s):  
Life Cycle ◽  
Condition Factor ◽  
River Estuary ◽  
Total Weight ◽  
Northeastern Brazil ◽  
Annual Life Cycle ◽  
Ucides Cordatus ◽  
Mangrove Crab ◽  
Significant Difference ◽  
The Relationship

The relationship between weight and size of individuals can be used to evaluate the status of a population, which is particularly useful for natural populations that are being exploited. Ucides cordatus occurs on the Atlantic coast of the American continent, from Florida (USA) to Santa Catarina (Brazil). This species is economically very important, most of all in the Northeastern area of Brazil, as well as in the Dominican Republic and Suriname. The objective of this study was to analyze life phases (‘fattening’, ‘matumba’, ‘milk-crab’, ‘maturation’ and ‘walking’) by use of the weight-length relationships, as well as temporal variations in this condition factor for each sex of U. cordatus. For this purpose, individuals were sampled monthly for twenty-four months at the Jaguaribe River estuary, Ceará State, Northeastern Brazil. The relationship between total weight and cephalothorax width was established using regression analysis, adjusted by a power equation. The dynamics of the condition factor were analyzed for each sex using the variation of its averages related to annual life cycle; this was done for each of the previously-mentioned phases. The relationship between total weight and cephalothorax width showed an isometric growth in males and negative allometric growth in females suggesting that, for the same reference size, males are heavier than females. When considering the average of the female condition factors, these were greater than those for males during the annual life cycle, except during the ‘maturation’ phase, which is the phase with a higher demand of energetic reserves for males. Annual variation of the condition factor in females presented no significant difference.

Instability waves on the air–sea interface

1993 ◽  
Vol 248 ◽  
pp. 363-381 ◽  
Author(s):  
G. H. Wheless ◽  
G. T. Csanady
Keyword(s):  
Surface Tension ◽  
Growth Rate ◽  
Maximum Growth ◽  
Maximum Growth Rate ◽  
Surface Velocity ◽  
Instability Waves ◽  
Interface Surface ◽  
Fluid Properties ◽  
Compound Matrix Method ◽  
Order Of Magnitude

We used a compound matrix method to integrate the Orr–Sommerfeld equation in an investigation of short instability waves (λ < 6 cm) on the coupled shear flow at the air–sea interface under suddenly imposed wind (a gust model). The method is robust and fast, so that the effects of external variables on growth rate could easily be explored. As expected from past theoretical studies, the growth rate proved sensitive to air and water viscosity, and to the curvature of the air velocity profile very close to the interface. Surface tension had less influence, growth rate increasing somewhat with decreasing surface tension. Maximum growth rate and minimum wave speed nearly coincided for some combinations of fluid properties, but not for others.The most important new finding is that, contrary to some past order of magnitude estimates made on theoretical grounds, the eigenfunctions at these short wavelengths are confined to a distance of the order of the viscous wave boundary-layer thickness from the interface. Correspondingly, the perturbation vorticity is high, the streamwise surface velocity perturbation in typical cases being five times the orbital velocity of free waves on an undisturbed water surface. The instability waves should therefore be thought of as fundamentally different flow structures from free waves: given their high vorticity, they are akin to incipient turbulent eddies. They may also be expected to break at a much lower steepness than free waves.

scholarly journals Submesoscale Cold Filaments in the Gulf Stream

2014 ◽  
Vol 44 (10) ◽  
pp. 2617-2643 ◽  
Author(s):  
Jonathan Gula ◽  
M. Jeroen Molemaker ◽  
James C. McWilliams
Keyword(s):  
Life Cycle ◽  
Gulf Stream ◽  
Baroclinic Instability ◽  
Vertical Mixing ◽  
Thermal Wind ◽  
Filament Dynamics ◽  
Oceanic Surface ◽  
Secondary Circulations ◽  
Order Of Magnitude ◽  
Surface Buoyancy

Abstract A set of realistic, very high-resolution simulations is made for the Gulf Stream region using the oceanic model Regional Oceanic Modeling System (ROMS) to study the life cycle of the intense submesoscale cold filaments that form on the subtropical gyre, interior wall of the Gulf Stream. The surface buoyancy gradients and ageostrophic secondary circulations intensify in response to the mesoscale strain field as predicted by the theory of filamentogenesis. It can be understood in terms of a dual frontogenetic process, along the lines understood for a single front. There is, however, a stronger secondary circulation due to the amplification at the center of a cold filament. Filament dynamics in the presence of a mixed layer are not adequately described by the classical thermal wind balance. The effect of vertical mixing of momentum due to turbulence in the surface layer is of the same order of magnitude as the pressure gradient and Coriolis force and contributes equally to a so-called turbulent thermal wind balance. Filamentogenesis is disrupted by vigorous submesoscale instabilities. The cause of the instability is the lateral shear as energy production by the horizontal Reynolds stress is the primary fluctuation source during the process; this contrasts with the usual baroclinic instability of submesoscale surface fronts. The filaments are lines of strong oceanic surface convergence as illustrated by the release of Lagrangian parcels in the Gulf Stream. Diabatic mixing is strong as parcels move across the filaments and downwell into the pycnocline. The life cycle of a filament is typically a few days in duration, from intensification to quasi stationarity to instability to dissipation.

scholarly journals Analysis of development of basic characteristics of the dairy industry in the Czech Republic

2005 ◽  
Vol 53 (6) ◽  
pp. 93-100
Author(s):  
Renata Kučerová
Keyword(s):  
Growth Rate ◽  
Czech Republic ◽  
Life Cycle ◽  
Dairy Industry ◽  
Raw Milk ◽  
The European Union ◽  
Agricultural Producers ◽  
The Czech Republic ◽  
Market Growth ◽  
Basic Characteristics

The paper deals with the analysis of changes in the development of basic characteristics of the dairy industry in the Czech Republic, which cohere with the integration of the Czech Republic into the European Union. The attention is paid on size of the market, growth rate, life cycle, development of prices and development of foreign trade. The total domestic consumption reached 2111.1 million litres in 2004. The industry is in the maturity. The excess of supply exists in the industry; the growth rate is low, under 5% per year. The integration of the Czech Republic into the EU didn’t bring about changes in the development of basic characteristics – size of the market, growth rate, and life cycle. The volume of production changed. The total volume of purchase of raw milk for production went down by 1.4% to the value in 2000. And all prices in the product vertical – milk and milk products (prices of agricultural producers, production prices and consumer’s prices) rose.The paper is a part of solution of the research plan of the FBE MUAF in Brno, No. MSM 6215648904.

Consistent patterns of maturity and density-dependent growth among populations of walleye (Sander vitreus): application of the growing degree-day metric

2010 ◽  
Vol 67 (7) ◽  
pp. 1057-1067 ◽  
Author(s):  
Paul A. Venturelli ◽  
Nigel P. Lester ◽  
Terry R. Marshall ◽  
Brian J. Shuter
Keyword(s):  
Growth Rate ◽  
Explanatory Power ◽  
Management Strategies ◽  
Fold Increase ◽  
Fish Growth ◽  
Growing Degree Days ◽  
Sander Vitreus ◽  
Degree Days ◽  
Regional Management ◽  
Dependent Growth

Growing degree-days (GDD, °C·days) are an index of ambient thermal energy that relates directly to an ectotherm’s cumulative metabolism but is rarely used to describe growth and development in fish. We applied GDD to length and maturity data from 416 populations of walleye ( Sander vitreus ) from Ontario and Quebec, Canada (mean annual GDD = 1200 to 2300 °C·days). On average, males matured after they had experienced 6900 °C·days and reached 350 mm total length (L) (n = 77 populations), and females matured after 10 000 °C·days and at 450 mm L (n = 70). Across 143 populations, GDD accounted for up to 96% of the variation in the length of immature walleye but also revealed a twofold difference in growth rate that was indicative of variation in food availability. When applied to data from eight populations in which walleye abundances have changed dramatically over time, GDD revealed a 1.3-fold increase in immature growth rate when abundance was low compared with when it was high. Our results both demonstrate the explanatory power of GDD with respect to fish growth and maturity and inform the development of regional management strategies for walleye.

Pucciniastrum americanum. [Descriptions of Fungi and Bacteria].

1969 ◽  
Author(s):  
G. F. Laundon
Keyword(s):  
New York ◽  
British Columbia ◽  
Life Cycle ◽  
Nova Scotia ◽  
Leaf Rust ◽  
Geographical Distribution ◽  
Picea Glauca ◽  
Yellow Rust ◽  
White Spruce ◽  
Rubus Idaeus

Abstract A description is provided for Pucciniastrum americanum. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Pycnia and aecia on Picea glauca (=P. canadensis), uredia and telia on Rubus idaeus (incl. R. strigosus) and R. leucodermis (raspberries). DISEASE: Needle rust of white spruce. Late leaf rust or late yellow rust of raspberry, infecting canes, leaves, petioles, calyces and fruits. GEOGRAPHICAL DISTRIBUTION: Canada and U.S.A. (widely distributed, recorded from British Columbia, Connecticut, Idaho, Illinois, Iowa, Mass., Md, Me, Montana, North Dakota, New Hamp., New Jersey, Nova Scotia, New York, Ohio, Ontario, Quebec, Vermont, Wisconsin, West Virginia). TRANSMISSION: Although the basidiospores infect Picea glauca (white spruce) (Darker, 1929) in some areas they probably play little part in the life cycle on raspberry since this rust is found on the latter host year after year in regions remote from any spruce trees (Anderson, 1956).

Changes in migration, carry-over effects, and migratory connectivity

2019 ◽  
pp. 93-107 ◽  
Author(s):  
Roberto Ambrosini ◽  
Andrea Romano ◽  
Nicola Saino
Keyword(s):  
Climate Change ◽  
Life Cycle ◽  
Population Size ◽  
Migratory Connectivity ◽  
Negative Effects ◽  
Annual Life Cycle ◽  
Northern Latitudes ◽  
Timing Of Migration ◽  
Tropical Areas ◽  
Carry Over

Studies of the timing (phenology) of bird migration provided some of the first evidence for the effects of climate change on organisms. Since the rate of climate change is uneven across the globe, with northern latitudes experiencing faster warming trends than tropical areas, animals moving across latitudes are subject to diverging trends of climate change at different stages of their annual life cycle, and, consequently, they can become mistimed with the local ecological conditions, with potentially negative effects on population size. This chapter reviews the modifications induced by climate change in different migration traits, like the timing of migration events, the distribution of organisms, and the direction and the speed of movements. It also considers the effects of ecological carry-over effects and migratory connectivity on the response of birds to climate change.

Degree-day models to predict carrot weevil (Coleoptera: Curculionidae) emergence and oviposition in Nova Scotia, Canada

2020 ◽  
Vol 152 (3) ◽  
pp. 374-388
Author(s):  
Suzanne Blatt ◽  
Deney Augustine Joseph ◽  
G. Christopher Cutler ◽  
A. Randall Olson ◽  
Scott White
Keyword(s):  
Nova Scotia ◽  
Adult Emergence ◽  
Hill Equation ◽  
Base Temperature ◽  
Degree Days ◽  
Eastern Canada ◽  
Leaf Stage ◽  
True Leaf ◽  
Listronotus Oregonensis ◽  
Carrot Weevil

AbstractCarrot weevil, Listronotus oregonensis (LeConte) (Coleoptera: Curculionidae), is a pest of carrot (Daucus carota var. sativus Hoffmann; Apiaceae) throughout eastern Canada. Carrot weevil emergence and oviposition were monitored in commercial carrot fields in Nova Scotia. Cumulative degree days were calculated using a base temperature of 7 °C (DD7), and models were developed to predict cumulative emergence and oviposition using nonlinear regression. Cumulative emergence and oviposition were adequately explained as functions of DD7 by a three-parameter sigmoidal Hill equation. Our emergence model predicted initial and peak adult emergence at 35 and 387 DD7, respectively, with oviposition on carrot baits occurring as early as 42 DD7. Models were then validated to evaluate how well they performed. Oviposition on carrot plants began at the fourth true-leaf stage (342 DD7) and continued until eleventh true-leaf stage. Growers using these models can identify their window of opportunity to manage their carrot weevil populations targeting the majority of emerged adults before oviposition begins in the field.

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