Ecology methods Flashcards
(34 cards)
Who was a key figure in the 1700s known for focusing on species classification and cataloguing?
Linnaeus
What concept, introduced by Tansley in 1935, led to a shift in conservation efforts towards preserving life complexity by considering species interactions and their environments?
The concept of ecosystems
Who popularised the term ‘biodiversity’ in 1985, making it central to conservation and policy?
E.O. Wilson
According to E.O. Wilson’s definition, what does biodiversity encompass?
“The totality of the inherited variation in all forms of life across all levels of variation from ecosystems to species to gene”. This definition emphasises the levels of biological organisation
What are the three components of biodiversity according to Noss (1990)’s multiscale concept?
1) Structure (physical organisation of habitats/ecosystems),
2) Composition (variety of species and genetic differences),
3) Function (ecological processes)
What type of diversity refers to the variety in the physical organisation and arrangement of habitats, ecosystems, and communities?
Structural diversity
What type of diversity is correlated with higher species richness, higher functional diversity, and a diverse array of ecosystem processes?
High structural diversity
What is functional diversity and how is it quantified?
Functional diversity refers to the components of biodiversity that influence how an ecosystem operates or functions.
It is quantified by measuring the range of different biological traits in a community
What type of diversity represents the species diversity within a particular area or ecosystem, often seen as species richness in a homogenous site?
Alpha diversity
What type of diversity measures the change or turnover in species composition between different habitats or ecosystems within a region?
Beta diversity
What type of diversity represents the total species diversity across multiple habitats or ecosystems within a larger region or landscape?
Gamma diversity
What type of diversity measures the change in species composition between ecosystem biomes separated by significant geographic or environmental barriers?
Delta diversity
What type of diversity represents the total diversity of a large geographic area or landscape, often applied over a whole biome context?
Epsilon diversity
Define ecology
the scientific study of the processes influencing the distribution and abundance of organisms, their interactions, and their interactions with energy and matter transformation
What are the three core biodiversity metrics commonly recorded?
Species richness (number of species),
Species composition (identity of species)
Species abundance (number of individuals per species)
When considering species richness, why is it important to also look at how ‘even’ the communities are?
High evenness (equal numbers of each species) indicates a community has higher diversity because no single species dominates.
Low evenness means species are not in equal numbers.
Name two diversity indices that account for both species richness and evenness/dominance.
The Shannon Index (considers richness and evenness, useful for overall ecosystem diversity)
Simpson’s Index (focuses more on dominance)
What is ‘cover’ in ecology, and what are three different types?
Cover is the area of the ground surface covered by vegetation or other materials, expressed as a percentage.
Types include
Basal cover (proportion extending into soil),
Canopy cover (vertical projection of foliage, can exceed 100%),
Ground cover (cover of the soil surface).
What is ‘density’ and for which types of organisms is it most often used, and why can it be difficult to measure in some vegetation types?
Density is the number of individuals per unit area.
It’s most often used for large plants or trees.
It can be difficult due to the difficulty of defining an individual, quadrat size effects at boundaries, and being time-consuming in dense or low-growing vegetation.
What is ‘frequency’ in ecological measurement and what does it indicate about a species?
Frequency is the proportion of plots of equal size in which at least one individual of a species occurs.
It indicates the uniformity of species distribution in an area
Name two common field methods using lines or defined areas for sampling.
Transects (lines used to estimate gradual change or guide sampling) and Quadrats (sampling areas of set size).
What method is commonly used in grasslands to assess dominant cover by recording what is felt underfoot along a transect?
the step point method
Why is sampling animals often harder than sampling plants?
Animals are mobile, behaviourally variable, and often hard to detect
Name 4 methods for sampling ground-dwelling invertebrates.
Pitfall traps,
Sweep nets,
Beating trays
Tullgren funnels
