Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

ENCN281 > Ecosystems > Flashcards

Ecosystems Flashcards

1
Q

limnology

A

study of lakes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

maximum density of water

A

occurs at 3.94oC

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Summer (Lake Processes)

A

stratification: most mixing at top (high temperature air) very little mixing at bottom

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Early Fall (Lake Processes)

A

turnover: water unstratifies, completely mixes until water at colder temp

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Late Fall (Lake Processes)

A

circulation: mixing slows down and stops when it reaches a constant temperature

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Winter (Lake Processes)

A

stratification: ice cover on top of lake

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Early Spring (Lake Processes)

A

turnover: as top layer heats from 0 to 4 oC it becomes more dense and sinks to bottom (slower/less mixing than autumn turnover)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Late Spring (Lake Processes)

A

circulation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Layers of Lake

A

from top to bottom (warmest to coldest)

  • Epilimnion
  • Metalimnion
  • Hypolimnion
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Diurnal Effects

A
  • during day: algae consume CO2 = increase pH

- during night: CO2 is produced which reacts to form H+ ions = decrease pH`

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Why are diurnal effects greater in autumn?

A

Turnover brings nutrient-rich deep water to surface = increase in algal growth = greater 02 and pH swings

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Trophic States

A

(lowest to highest nutrients)

  • Oligotrophic
  • Mesotrophic
  • Eutrophic
  • Hypertrophic
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Trophic status determined by:

A

amount of limiting nutrient (either phosphorous or nitrogen)
- algae produced until either N or P at low levels and no more biomass produced = one that is at low levels is the limiting nutrient

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Eutrophication definition

A

process of becoming more eutrophic - accelerated by humans

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Impacts of Eutrophication

A
  • nuisance or toxic algal blooms in summer
  • fish kills due to low dissolved oxygen (or migration)
  • taste and odour problems with drinking water
  • reduced quality of recreational use
  • increased density of aquatic weeds in shallow areas
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Big eutrophication problems in NZ

A
  1. Lake Ellesmere (already very eutrophic)

2. Lake Taupo/Rotorua (threat of becoming eutrophic)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Lake Management Methods

A
  1. Reduce input of nutrients
  2. Remove stock of nutrients
  3. Isolate stock of nutrients
  4. Increase Depth
  5. Artificially restore ecosystem
  6. Biomanipulate to new equilibrium
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Point Source Control

A

advanced wastewater treatment at wastewater discharge locations or plants

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Nonpoint Source Control

A

increase land are protected by conservation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Diversion

A

stop treated waters getting in to water system rather than limiting/controlling amount going in

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Dredging

A

increase depth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Chemical inactivation

A

addition of alum to reduce sediment P release

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Hypolimnetic aeration

A

oxygen bubbled into bottom of reservoir to maintain DO levels

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Herbicides/Harvesting

A

treatment with herbicide to eliminate exotic invasive species

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Biomanipulation

A

introduction of new animal species

26
Q

Lake Management Examples

A
  • point source control
  • non point source control
  • diversion
  • dredging
  • chemical inactivation
  • hypolimnetic aeration
  • herbicides/harvesting
  • biomanipulation
27
Q

what is a system?

A

collection of related parts that represents the purpose or essence of a concept

28
Q

what is a model

A

tool used to analyse a system

29
Q

Rich pictures

A

used for initial understanding

30
Q

Mind maps

A

ideas with structure emphasised and not links

31
Q

Hierachy Trees

A

used to show structure and imply relations between parts

32
Q

Entity Process diagram

A

used to distinguish between people and activities

33
Q

Logic Flow Diagrams

A

Step by step to set out process

34
Q

Cross-functional Diagram

A

used as a system that is a process with time coordination

35
Q

Entailment trees

A

(fault trees)

used to show logic behind a system

36
Q

Influence Diagrams

A

used to show feedback processes that occur over time

37
Q

Stock/Flow Diagrams

A

allows for mathematical modelling of dynamic systems

38
Q

Healthy System Diagram Criteria

A
  1. Balance
  2. Completeness
  3. Cohesion
  4. Discrimination
  5. Consistency
39
Q

carrying capacity

A

upper limit to growth

40
Q

Limits to growth

A
  • limited food
  • limited living space
  • limited breeding sites
  • limited nutrients
  • excessive contact betwen individuals
41
Q

Types of Species Interactions

A
  1. Competition
  2. Exploitation
  3. Commensalism
  4. Inhibition
  5. Mutualism
42
Q

Competition

A

varying growth rates - local extinction

- leads to specialisation in ecological niches or extinction

43
Q

Exploitation

A

benefits one species at expense of other species

e.g. predator prey, herbivory (sheep and grass), parasitism (humans and tapeworms)

44
Q

Commensalism

A

helps one species - negligible effect on the other

e.g. mild parasites

45
Q

Inhibition

A

harms one species with negligible impact on the other

e.g. mild competition

46
Q

Mutualism

A

benefits both species

e.g. plants and birds

47
Q

Biodiversity formation

A
  1. Random Mutation
  2. Natural Selection
  3. Extinction or Specialisation
    - results from a long slow process of coevolution
48
Q

Primary Production

A

must have species that turn source energy (sun, geo) into biomass
- like the base of a pyramid

49
Q

GPP

A

gross primary production = total energy converted / area-time

50
Q

NPP

A

net primary production = energy converted - maintenance

51
Q

Requirements for Primary Production

A
  • Warmth
  • Sun
  • Moisture
  • Pressure
  • Nutrients (N,P)
  • Lack of Toxins
52
Q

greater Primary Production

A

the greater the PP = more energy flows at higher levels of pyramid = more biodiversity

53
Q

Bioaccumulation

A
  • occurs when toxins are not destroyed in organisms and are not lost with the organisms waste
  • important for human health with lead and fish in lake rotorua
54
Q

Food/Energy relationships should be seen as webs or chains?

A

webs

55
Q

Do populations higher on a food web decrease or increase in number?

A

Decrease in number because the available energy decreases as they consume those lower on the web

56
Q

Does available energy decrease or increase as one progresses up a food web?

A

decreases

57
Q

Steady State System

A

sum of flows in = sum of flows out

58
Q

Residence time

A

= stock / sum of flows out = stock / sum of flows in

a key variable

59
Q

Elemental Abundance

A
  • species have co-evolved to use the elements that are available
60
Q

Phosphorous cycle

A
  • physical states: solid and liquid
  • quick cycle
  • variety of cycles
  • strong human influence
  • sustainability issues
  • inorganic and organic forms
61
Q

Nitrogen Cycle

A
  • physical states: gas, solid, liquid
  • inorganic and organic forms
  • fast biological process but sits within larger system of slower processes

ENCN281 (5 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions