BACCALAUREATE INTERNATIONAL INTERNACIONAL
ENVIRONMENTAL SYSTEMS Standard Level Paper 2
Subject Details: Environmental Systems SL Paper 2 Markscheme General A markscheme often has more specific points worthy of a mark than the total allows. This is intentional. Do not award more than the maximum marks allowed for part of a question. When deciding upon alternative answers by candidates to those given in the markscheme, consider the following points: Each marking point has a separate line and the end is signified by means of a semicolon (;). An alternative answer or wording is indicated in the markscheme by a “/”; either wording can be accepted. Words in ( … ) in the markscheme are not necessary to gain the mark. The order of points does not have to be as written (unless stated otherwise). If the candidate’s answer has the same “meaning” or can be clearly interpreted as being the same as that in the mark scheme then award the mark. Mark positively. Give candidates credit for what they have achieved, and for what they have got correct, rather than penalising them for what they have not achieved or what they have got wrong. Remember that many candidates are writing in a second language. Effective communication is more important than grammatical accuracy. Occasionally, a part of a question may require a calculation whose answer is required for subsequent parts. If an error is made in the first part then it should be penalised. However, if the incorrect answer is used correctly in subsequent parts then follow through marks should be awarded. Indicate this with “ECF”, error carried forward. Units should always be given where appropriate. Omission of units should only be penalised once. Indicate this by “U-1” at the first point it occurs. Ignore this, if marks for units are already specified in the markscheme. Do not penalise candidates for errors in significant figures, unless it is specifically referred to in the markscheme.
–6– SECTION A 1. (a)
crude birth rate − crude death rate ; 10 Definition in continuous prose is allowed.
natural increase =
Gaza has the highest NIR; 49 − 5 = 4.4 ; Gaza NI = 10 70 = 15.9 years ; doubling time = 4.4 both territories could be described as having high population growth, but for different reasons; India: very large population base so a modest rate of increase (1.9 %); means that population increases by a large absolute number each year (18.75 million); Gaza: very small total population (1.2 million) so a high rate of increase (4.4 %); produces only a modest increase in numbers (52,800); larger absolute population size of India likely to have larger impact globally; high rate of increase in Gaza may mean large numbers of people entering reproductive age / future problems;
Any two of the following. area of land; available resources; rate of resource consumption; imports and exports; carrying capacity = the maximum number of a species or “load” that can be sustainably supported by a given environment / OWTTE; human communities can exchange (though imports and exports) resources with others; … thus a country may have a “footprint” / resource base that extends beyond its boundaries; capacity also depends on level of technology; some argue there are no limits to capacity; … some small countries (e.g. Netherlands) are able to support high population densities at a high standard of living; per capita consumptions are not constant from time to time / place to place;
–7– 2. (a) (i) inputs = outputs, therefore no net change; Do not allow constant input and output. X=2
  
open; matter (and energy) are inputs and outputs; Candidates must state “matter” for the mark. Allow any logical and appropriate argument for [2...