Ecology Flashcards
Pelagic
Relating to upper layers of the open sea.
Benthic
Anything associated with or occurring on the bottom of a body of water. The animals and plants that live on or in the bottom are known as the benthos.
Four shapes of marine bacteria
Bacillus, Vibrios, Spirilli, Coccus
Photoautotrophs
use of light as a source of
E for the synthesis of organic matter
Chemoautotrophs
obtain E from the
oxidation of reduced and inorganic
compounds (e.g., nitrifying bacteria,
sulphobacteria, methanogens)
Heterotrophs
are unable to synthesize
organic matter autonomously from inorganic
molecules
Viriobenthos
viruses in marine sediments or within benthic
organisms.
Virioplankton
viruses in sea water o planktonic organisms.
Viruses
biological entities of sub-microscopic size, which
cannot live or reproduce outside the host cells because they lack
metabolic activity and biosynthetic functions.
100 nm
Viruses have single- or doublestranded DNA or RNA, but never
both nucleic acids.
They infect all forms of life (e.g.
animals, plants, fungi), including
prokaryotes.
Capsid
The proteic coat that surrounds the viral genome
Capsomers
Identical repeating units of the capsid
Size of most marine viruses
Between 30 and 60 nm in size
Viral abundance in seawater
1 L of sea water contains 10^9 to 10^11 viruses
Viral abundance in sediment
1 kg of sediment contains 10^10 to 10^13 viruses
Factors influencing the abundance of Benthic Viruses
prokaryotic production, concentration of nutrients, organic matter load of sediments
Viral shunt
The viral shunt pathway is a mechanism that prevents (prokaryotic and eukaryotic) marine microbial particulate organic matter (POM) from migrating up trophic levels by recycling them into dissolved organic matter (DOM), which can be readily taken up by microorganisms.
Population
All organisms of a certain species living in a specified area
Demography
Statistical study of populations – to describe populations and how
they change over time
Mark-recapture calculation
N (population size)
M (marked)
C (captured)
R (animal found to be marked)
N = MC/R
Types of survivorship curves
Type 1 - Convex, Type 2 - Diagonal, Type 3 - Concave
image: https://cdn.britannica.com/42/6542-050-B6E0E2B9/survivorship-curve-II-Type-I-curves-III.jpg
Trophic Level
The trophic level of an organism is the position it occupies in a food web.
Just a reminder to review calculating trophic levels!
Unit 4 - Foodwebs
Fecundity
the ability to produce an abundance of offspring or new growth; fertility.
Order of taxonomy
Kingdom Phylum Sub Phylum Class Order Family Genus Species
Semelparity
A species is considered semelparous if it is characterized by a single reproductive episode before death
Iteroparity
A species is considered iteroparous if it is characterized by multiple reproductive cycles over the course of its lifetime.
Phytoplankton
Plankton that produce there own food (autotrophic/photosynthesize); primary producers.
Holoplankton
organisms spend entire life as plankton
Meroplankton
spend larval stage as plankton
r/K selection
r/K selection theory relates to the selection of combinations of traits in an organism that trade off between quantity and quality of offspring.
Logistic growth
In logistic growth, population expansion decreases as resources become scarce, leveling off when the carrying capacity of the environment is reached, resulting in an S-shaped curve.
Density dependence
In population ecology, density dependence pertains to the effect of the present and/or the past population sizes on the per capita population growth rate. Density-dependent processes take place when population growth rates are regulated by population density
Life history patterns
Life-time pattern of growth, differentiation, storage and reproduction
OR
Characteristic set of biological episodes and responses occurring during the lifetimes of the individuals in a population
- Connection between environment and biological responses
- Variability in life history traits (plasticity)
Life history strategy
a set of traits resulting from natural selection
r/K
K = carrying capacity r = intrinsic growth rate
dN/dt = rN (1-N/K)
Logistic model where:
N = Abundance t = time K = carrying capacity r = intrinsic growth rate
r selected traits
fast growing, opportunistic, live in unpredictable habitats, broad niche, high fecundity, early reproduction, high/catastrophic mortality, short lived, highly productive. High resilience to exploitation (ex: sardines, anchovies) mnemonic reminder: saRdines
K selected traits
Population controlled by competition and other factors, choose constant or predictable habitats, narrow niche, large body size, low fecundity, delayed reproduction. Low resilience to exploitation (ex: elephants, sharks) mnemonic reminder: sharKs
Mutualism
symbiosis that is beneficial to both organisms involved.
Plankton
All living organisms drifting in the ocean
Bottom-up control
Resource/environmental control over a community of organisms (i.e. Nitrate related green tides in Brittany)
Top-down control
Organisms control over a resource/environment (i.e. predator control over rodent populations)
Exponential growth curve equation
dN/dt = rN
where
N = Population density at time (t)
r = intrinsic rate of natural increase
K = carrying capacity
Logistic growth curve equation
dN/dt = rN(K-N/K)
where
N = Population density at time (t)
r = intrinsic rate of natural increase
K = carrying capacity
OMZ
Oxygen minimum zones
Pelagic Habitat compression
-
azoic theory
Theory that there is no life below 600m due to extreme pressure conditions and the presumed absence of oxygen
Challenger expedition
1872-1876 - discovered 4700 new species
Magnometer
A magnetometer is a passive instrument that measures changes in the Earth’s magnetic field. In ocean exploration, it can be used to survey cultural heritage sites such as ship and aircraft wrecks and to characterize geological features on the seafloor.
Deep Sea Hydrophone
Underwater microphone
CDT
CTD stands for conductivity, temperature, and depth, and refers to a package of electronic devices used to detect how the conductivity and temperature of water changes relative to depth. The CTD is an essential tool used in all disciplines of oceanography, providing important information about physical, chemical, and even biological properties of the water column.
Shelf break starts at
approx 200m with the exception of the antarctic shelf break
DOC and POC
Dissolved and Particulate Organic Carbon
POM
Particulate organic matter (POM) is a fraction of total organic matter operationally defined as that which does not pass through a filter pore size that typically ranges in size from 0.22 and 0.7 micrometers. The fraction that does pass through the filter is called dissolved organic matter (DOM).
Meiobenthos
Meiobenthos, also called meiofauna, are small benthic invertebrates that live in both marine and fresh water environments. The term meiofauna loosely defines a group of organisms by their size, larger than microfauna but smaller than macrofauna, rather than a taxonomic grouping
Estuary
Mixed fresh and ocean water areas
Epifauna
animals living on the surface of the seabed or a riverbed, or attached to submerged objects or aquatic animals or plants.
vagile/sessile
vagile - moves
sessile - lives permanently attached to rocks/seaweeds
Types of Marine Forests
Any plants that have the capacity to conduct oxygenic photosynthesis in the ocean: Kelp forests, seagrasses, animal forests, mangroves, saltmarshes, microalgae, etc
Climatic refugal populations
Populations that survive in the overlap of warm and cold ranges.
Neritic Zone
Another name for continental shelf; penetration of sunlight permits photosynthesis by both plankton and bottom-dwelling organisms.
SAAB
Sense Acuity And Behavioral hypothesis; Temperate fish larvae use a hierarchy of sensory cues (odor, sound, visual and geomagnetic cues) to detect estuarine nursery areas and to aid during navigation towards these areas.
Recruitment
Relationship between number of spawners and the resulting progeny; recruitment is the process by which individuals are added to a population. … High recruitment may increase a species’ current and future abundance within a system, whereas low recruitment can lead to reduced current and future abundance.
