ECOLOGY
Paper details:

This is an investigation which I have already started. I try to assess the status of health of a fresh water ecosystem. What I want to do through this investigation will become clearer by reading what I have already done so far. I have already collected and processed the data for the ecosystem I am investigating. You need to write an EVALUATION in which you just need to compare them with some other data for the same indicators that I used, which you will need to find. This means you need to research the data from another ecosystem of the same type as mine, which is considered to be healthy and compare my results with those in order to assess whether the ecosystem which I investigated is healthy or not. Then write a CONCLUSION in which you state whether my results make the ecosystem that I looked at healthy or not, and eventually write how I could improve my method in doing this investigation. I will upload the syllabus of my ecology course so that you can relate to it and write the evaluation on the base of what I have studied. This is the mark scheme for this kind of assessment: https://ibpublishing.ibo.org/server2/rest/app/tsm.xql?doc=d_4_biolo_gui_1402_1_e&part=9&chapter=5

Essential idea:Community structure is an emergentproperty of an ecosystem.

C.1Species and communities
Nature of science:
Use models asrepresentations of the realworld—zones of stress and limits of tolerance graphs are models of the realworldthathave predictive power and explaincommunity structure. (1.10)
Understandings:
• Thedistribution of species isaffectedbylimiting factors.
• Community structure can be strongly affectedbykeystone species.
• Each species plays a unique role within a community because of the uniquecombination of its spatial habitat and interactions with other species.
• Interactionsbetweenspeciesinacommunitycanbeclassifiedaccordingtotheireffect.
• Twospeciescannotsurviveindefinitelyinthesamehabitatiftheirnichesareidentical. Theory of knowledge:
• Random samples aretakenin studies involving large geographicalareas or if limitedtimeisavailable.Is random sampling a useful tool forscientistsdespite the potential for sampling bias?
Utilization:
Syllabus and cross-curricular links:Geography
Part 2CExtremeenvironments
Aims:
• Aim 6: Factors influencing herbivory couldbeinvestigated.
Quality of your understanding, applications and skills:

Before studying: 1 2 3
Priorities when studying through reading and note taking:

After studying: 1 2 3
Areas of concern and actions to take:
Evidence from test: 1 2 3
Action to improve: Bullet-point examples that illustrate international – mindedness, TOK and utilization points

C.1Species and communities
Applications and skills:
• Application:Distribution of one animal and one plant species toillustrate limits oftolerance and zones of stress.
• Application: Local examples toillustrate the range of waysinwhich species caninteract within a community.
• Application:The symbiotic relationshipbetweenZooxanthellaeand reef-buildingcoral reef species.
• Skill:Analysis of a data set thatillustrates the distinction between fundamentaland realized niche.
• Skill:Use of a transect tocorrelate the distribution of plant or animal species withan abioticvariable.
Quality of your understanding, applications and skills:

Before studying: 1 2 3
Priorities when studying through reading and note taking:

After studying: 1 2 3
Areas of concern and actions to take:
Evidence from test: 1 2 3
Action to improve: Bullet-point examples that illustrate international – mindedness, TOK and utilization points

Essential idea:Changesin community structure affect and areaffectedbyorganisms.

C.2 Communities and ecosystems
Nature of science:
Use models asrepresentations of the real world—pyramids of energy model the energy flowthrough ecosystems. (1.10)
Understandings:
• Most species occupy different trophiclevelsinmultiple food chains.
• A food webshowsall the possible food chainsin a community.
• Thepercentage of ingested energy convertedtobiomassis dependent onthe respirationrate.
• Thetype of stable ecosystem thatwill emerge in an areais predictable basedon climate.
• In closed ecosystems energy but not matter is exchanged with thesurroundings.
• Disturbance influences the structure and rate of changewithin ecosystems. Theory of knowledge:
• Do the entitiesinscientists’ models, for example trophiclevels or Gersmehldiagrams, actually exist, or aretheyprimarily useful inventions for predictingand explaining the natural world?
Utilization:
• Poikilotherms(animalsthathave a variable bodytemperature)aremoreeffectiveproducers of proteinthan homeotherms (animalsthatmaintain aregulatedbodytemperature)astheyhave a higher rate of conversion of foodtobiomass.
Syllabus and cross-curricular links:Biology
Topic4.2 Energy flow
Quality of your understanding, applications and skills:

Before studying: 1 2 3
Priorities when studying through reading and note taking:

After studying: 1 2 3
Areas of concern and actions to take:
Evidence from test: 1 2 3
Action to improve: Bullet-point examples that illustrate international – mindedness, TOK and utilization points

C.2 Communities and ecosystems
Applications and skills:
• Application:Conversionratioinsustainable food production practices.
• Application:Consideration of one example of howhumans interfere withnutrient cycling.
• Skill:Comparison of pyramids of energy from different ecosystems.
• Skill:Analysis of a climograph showing the relationshipbetweentemperature,rainfall and the type of ecosystem.
• Skill: Construction of Gersmehl diagramstoshow the inter-relationshipsbetweennutrientstores and flows between taiga, desert and tropicalrainforest.
• Skill:Analysis of data showing primary succession.
• Skill:Investigationinto the effect of an environmentaldisturbance on anecosystem.
Guidance:
• Examples of aspectstoinvestigatein the ecosystem couldbe speciesdiversity,nutrient cycling, watermovement,erosion, leaf area index, amongothers.
Quality of your understanding, applications and skills:

Before studying: 1 2 3
Priorities when studying through reading and note taking:

After studying: 1 2 3
Areas of concern and actions to take:
Evidence from test: 1 2 3
Action to improve: Bullet-point examples that illustrate international – mindedness, TOK and utilization points

Essential idea:Human activities impact on ecosystem function.

C.3Impacts of humans on ecosystems
Nature of science:
Assessing risks and benefitsassociated with scientific research—the use of biological controlhasassociatedrisk and requires verification bytightlycontrolledexperiments before it isapproved.(4.8)
Understandings:
• Introducedalien species can escape into local ecosystems and becomeinvasive.
• Competitiveexclusion and the absence of predators can lead to reduction inthe numbers of endemic species when alien species become invasive.
• Pollutants become concentratedin the tissues of organismsat higher trophiclevelsby biomagnification.
• Macroplastic and microplasticdebrishasaccumulatedin marineenvironments.
Applications and skills:
• Application:Study of the introduction of cane toadsinAustralia and oneother local example of the introduction of an alien species.
• Application:Discussion of the trade-offbetweencontrol of the malarialparasite and DDT pollution.
• Application: Case study of the impact of marine plastic debris on Laysanalbatrosses and one other named species.
• Skill:Analysis of data illustrating the causes and consequences ofbiomagnification.
• Skill:Evaluation of eradication programmes and biological controlasmeasurestoreduce the impact of alien species. International-mindedness:
• Over 100countriesacross the globe have agreed to ban the production ofCFCstoreduce the depletion of the ozonelayer.
Aims:
• Aim 8:Many developed countriesexporttoxicwastetoless developedcountries.Is financial compensation a fairexchange for hazardous waste?
Quality of your understanding, applications and skills:

Before studying: 1 2 3
Priorities when studying through reading and note taking:

After studying: 1 2 3
Areas of concern and actions to take:
Evidence from test: 1 2 3
Action to improve: Bullet-point examples that illustrate international – mindedness, TOK and utilization points
Essential idea:Entirecommunitiesneedtobe conserved in order to preserve biodiversity.

C.4Conservation of biodiversity
Nature of science:
Scientistscollaboratewithotheragencies—thepreservationofspeciesinvolvesinternationalcooperationthroughintergovernmentalandnon-governmentalorganizations.(4.3)
Understandings:
• An indicator species is an organism used toassess a specific environmentalcondition.
• Relative numbers of indicator species can be used tocalculate the value of abiotic index.
• In situconservation mayrequire active management of nature reserves ornationalparks.
• Exsituconservationisthepreservationofspeciesoutsidetheirnaturalhabitats.
• Biogeographic factors affect species diversity.
• Richness and evennessare components of biodiversity.
Applications and skills:
• Application: Case study of the captive breeding and reintroduction of anendangered animal species.
• Application:Analysis of the impact of biogeographic factors on diversitylimitedtoislandsize and edge effects.
• Skill:Analysis of the biodiversity of two local communitiesusingSimpson’sreciprocal index of diversity.
Aims:
• Aim 8: Scientists supported bygovernmentsaredevotingrelativelylarge amounts of efforttosave particular animal species. Can criteriabeestablished to justify a hierarchy of value of one species overanother?

Guidance:
• The formula for Simpson’s reciprocal index of diversity is:
D=diversityindex,N=totalnumberoforganismsofallspeciesfoundandn=number of individuals of a particular species.
Quality of your understanding, applications and skills:

Before studying: 1 2 3
Priorities when studying through reading and note taking:

After studying: 1 2 3
Areas of concern and actions to take:
Evidence from test: 1 2 3
Action to improve: Bullet-point examples that illustrate international – mindedness, TOK and utilization points