Self-study
P1
As part of an international effort to address environmental problems resulting from agricultural overproduction, hundreds of thousands of acres of surplus farmland throughout Europe will be taken out of production in coming years. ███
Problem and Solution ·
Problem: overproduction / solution: let farms lie fallow
We're farming too hard and that's harming the environment. Solution is to let farms sit there and don't plant anything.
Problem Details ·
Too few nutrients; too much fertilizer
Farming depleted nutrients and introduced fertilizers. That makes it difficult to restore the land to "natural balance of flora." In particular, thistles (a weed) will crowd out other flora.
Impractical Solution ·
Remove and replace the topsoil
Impractical because we're not talking about my backyard garden. We're talking at the scale of hundreds of thousands of acres.
Potential Solution ·
Artificially accelerate recovery
Netherlands is doing a study to see if they can speed up natural recovery.
P2
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Experimental Setup ·
Control v. intervention groups
Two control groups: (C1) lie fallow and (C2) grow corn. Two intervention groups: (I1) grow mixture of native flora and (I2) grow native flora plus clover and toadflax.
Results ·
Intervention works
Both intervention groups forced out thistles (a weed). The fallow control group (C1) was overtaken by thistles.
P3
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Experiment setup ·
Another intervention group
(C3) grow mixture of native flora and mix in 20 years recovered soil. This intervention group is meant to test whether microorganisms in the soil would have beneficial effects.
Results ·
Intervention works
Flora grew better on the enriched plots.
Conclusion ·
Microorganisms in the soil are important for restoring natural flora
Researchers conclude (hypothesize with supporting evidence) that over farmed land contain too many disease organisms and too few beneficial organisms.
Solution ·
Sow beneficial microorganisms into soil
Passage Style
Problem-analysis
Single position
26.
It can be inferred from ███ ███████ ████ ██ ███ ███████ █████████ █████████ ██
a
Populations of symbiotic ██████████ ████ ████ ██ ███ ████ █████ █████████ ████████
We have no reason to think that eliminating harmful organisms would lead to fewer of the beneficial organisms. The beneficial organisms live symbiotically on plant roots; this doesn’t suggest that eliminating harmful organisms will reduce the beneficial organisms.
b
Unwanted plant species ████ ████████ █████ ██ ██████ ██ ████████
“Unable” is too strong. We have no reason to think that thistles would be “unable” to survive. Perhaps there would be fewer thistles or a lower proportion of thistles compared to native plants, but this doesn’t imply a complete inability to grow.
c
The chance of ████████ ██ █ ██████████ ██████ █████ █████ █████████
Supported, because being overrun with disease organisms is what likely explains why heavily farmed land doesn’t allow native grasses and herbs to grow as well as land that has been out of production. So there’s reason to think that eliminating the disease organisms from heavily farmed land would encourage the growth of native grasses and herbs.
d
The number of ███ █████ ██ ██████████ ██████████████ █████ ████████ ██ ███ ████ █████
We have no reason to think that “all” beneficial microorganisms would increase. Not only is “all” too strong, but the author also never suggests that the existence of the harmful microorganisms stops the beneficial microorganisms from existing.
e
Populations of other █████ ██ ███████ █████████ █████ ████████ ███████████████
We have no reason to think that eliminating the disease organisms discussed would lead to an increase in other disease organisms. The author never connects the population of some disease organisms to the population of other disease organisms.