Date | May 2019 | Marks available | 9 | Reference code | 19M.2.SL.TZ0.7 |
Level | Standard Level | Paper | Paper 2 | Time zone | Time zone 0 |
Command term | Discuss | Question number | 7 | Adapted from | N/A |
Question
Identify four factors that make the estimation of carrying capacity more problematic for human populations than for most other species.
Explain why the ecological footprint of two populations consuming the same quantity of food and energy may be different.
Discuss the potential for designing a protected forest area that allows for the harvesting of natural resources while at the same time conserving its biodiversity.
Markscheme
Humans:
- use such a wide range of resources that could be limiting;
- have a greater ingenuity to increase efficiency of resource use/substitute resources for one another;
- local populations can import resources from elsewhere;
- show great variation in lifestyles/demand from place to place;
- depend on technological development demanding different resources overtime;
- …making it difficult to identify any one limiting factor/resource for carrying capacity;
- produce a diverse range of wastes damaging their habitat/reduce carrying capacity;
[4 max]
a population may consume the same as another but produce more (for export or just wasted) which will increase its EF/require more land;
food production systems may be different in terms of efficiency / sustainability;
…some may be more intensive / use advanced technology / fertilisers;
…or rely less heavily on meat products / more heavily on vegetarian products;
…or be located in a climate more favourable to food production;
…and therefore, produce same quantity of food with less land/lower EF;
energy production may rely more heavily on renewable sources/solar energy/hydroelectricity/wind power;
…or be located in regions with higher rates of primary productivity/photosynthesis;
…employ more effective mitigation strategies;
…so, absorb carbon wastes with less local land/lower EF;
activities other than food and energy provision may influence ecological footprint (eg urbanization/water pollution);
one population may lack treatment facilities / regulations for wastewater leading to greater EF;
one population may live in multistory buildings / smaller houses using less land so lower EF;
Note: Question addresses difference in footprints between populations not per capita footprints.
Award [4 max] for responses that address only food or only energy production OR for responses that make no reference to actual difference in EF or land required.
[7 max]
The following guide for using the markbands suggests certain features that may be offered in responses. The five headings coincide with the criteria given in each of the markbands (although “ESS terminology” has been conflated with “Understanding concepts”). This guide simply provides some possible inclusions and should not be seen as requisite or comprehensive. It outlines the kind of elements to look for when deciding on the appropriate markband and the specific mark within that band.
Answers may include:
- understanding concepts and terminology of sustainable harvesting/yield, natural capital/income, renewable vs non-renewable resources, reserves/protected areas, habitat vs species conservation, ecological pyramids, edge effects, design principles of conservation areas, ecotourism, local/national/international organisations, community support, etc;
- breadth in addressing and linking effective conservation with eg size ,shape, location of protected areas, central “no-go” zone/wilderness, use of corridors, roles of international organisations, local ownership, etc. Also with sustainable harvesting eg managing sustainable yield, reducing collateral impacts of infrastructure, raising funds and incentive for conservation, subsistence of local populations, commercial value of harvestable goods, etc;
- examples of supporting biodiversity through large area/food base, circular shape to reduce edge effects, links to other areas via corridors to increase genetic mixing, maintaining certain/central area with no human activity, promoting local support by providing employment/resources/income, gaining global support through international bodies UNEP, Greenpeace etc;
- balanced analysis of ways in which, and the extent to which, in a variety of geographical/social contexts, a protected area can or cannot support harvesting while at same time conserving biodiversity;
- a conclusion that is consistent with, and supported by, analysis and examples given eg “one of the greatest contributions to successful conservation is a local “ownership” of the project and therefore, provided the harvesting is limited to certain areas and sustainably managed, there could be considerable potential for such a design to provide very successful conservation”;
[9 max]
Refer to paper 2 markbands, available under the "your tests" tab > supplemental materials.
Examiners report
Many candidates gained a mark or two here for mentioning diversity in lifestyles or technological developments but many responses were too vague or addressed irrelevancies of population demographics.
Most candidates were able to identify differences in diet and energy sources but few were able to identify other factors affecting ecological footprints. Some addressed irrelevancies of population sizes.
Responses tended to show either some understanding of principles of design for protected areas or of principles for sustainable harvesting, but rarely both.