Reading Practice Test 9: City and Soil

Read the text below and answer questions 1-13.

The Hidden Cost of Urban Noise

Air pollution has long dominated public health discussions about city living, but a growing body of research suggests that chronic noise exposure deserves comparable attention. Public health researcher Adaeze Nwosu has spent much of the last decade documenting how constant low-level noise — traffic, construction, aircraft — affects the body in ways that have little to do with hearing damage itself.

Nwosu's central finding concerns the cardiovascular system. In a long-running study following residents near a major airport, participants living in areas with the highest average noise levels showed measurably elevated rates of high blood pressure and heart disease compared to demographically similar residents in quieter neighbourhoods, even after controlling for factors such as air pollution and income. The mechanism, Nwosu argues, runs through the body's stress response: chronic noise exposure, even at volumes too low to consciously register as bothersome, appears to keep stress hormone levels persistently elevated, placing sustained strain on the cardiovascular system over years.

Sleep disruption compounds the problem. Nwosu's team fitted volunteers with sensors capable of detecting brief awakenings too short to be consciously remembered the next morning, and found that traffic noise during sleep triggered far more of these micro-awakenings than participants realised — people who reported sleeping soundly through the night had, in many cases, been woken dozens of times without any memory of it. Because these fragmented sleep patterns don't register subjectively, Nwosu suggests many people underestimate how much environmental noise is affecting their rest and, by extension, their long-term health.

Children appear particularly vulnerable to a different category of effect. Several studies Nwosu has reviewed found that children attending schools near busy roads or flight paths performed measurably worse on reading comprehension and memory tasks than children at quieter schools, even when the schools were otherwise comparable in resources and teaching quality. The leading explanation is that intermittent loud noise repeatedly interrupts the sustained attention required for reading tasks, an effect that accumulates significantly over a school year of regular disruption.

Addressing urban noise is complicated by the fact that, unlike many pollutants, it cannot simply be filtered out at the source in most cases. Nwosu points to a mix of approaches showing promise in cities that have taken the problem seriously: noise barriers along major roads, quieter road surfacing materials, stricter aircraft noise regulations during night hours, and urban planning that keeps residential buildings and schools at greater distances from major noise sources where possible. She is careful to note that no single measure eliminates the problem entirely, and that noise reduction, unlike some public health interventions, generally requires sustained investment in infrastructure rather than a one-time fix.

Read the text below and answer questions 14-26.

The Rise of Vertical Farming

As cities expand and arable land per person continues to shrink globally, a growing number of agricultural engineers have turned their attention to a radical alternative: growing crops not across horizontal fields, but stacked vertically in climate-controlled indoor facilities, often located within or near the cities where the food will ultimately be consumed.

Vertical farms typically use hydroponic or aeroponic systems, delivering nutrients directly to plant roots through water or a fine mist rather than soil, stacked in trays across multiple levels within a warehouse-like structure. LED lighting, tuned to the specific wavelengths plants use most efficiently for photosynthesis, replaces natural sunlight, allowing continuous growing cycles unaffected by season, weather, or daylight hours. Proponents argue this control over growing conditions allows for dramatically higher yields per unit of land area than conventional farming, since multiple growing levels effectively multiply the usable area within the same building footprint.

Water efficiency is frequently cited as one of vertical farming's strongest advantages. Because hydroponic systems recirculate water rather than allowing it to drain into surrounding soil, well-designed vertical farms can use a small fraction of the water required by equivalent conventional crop production, an advantage that becomes particularly significant in regions facing water scarcity. The controlled indoor environment also largely eliminates the need for pesticides, since pests common to open fields rarely gain access to a sealed growing facility.

The technology's limitations, however, have kept it from expanding as rapidly as early enthusiasts predicted. Energy costs are substantial, since LED lighting and climate control systems run continuously and represent a significant ongoing operating expense that field-grown crops relying on natural sunlight simply don't incur. This has confined most commercial vertical farms to high-value, fast-growing crops such as leafy greens and herbs, where the premium price commanded by the product can offset energy costs — staple crops like wheat or rice, which require far more space per calorie produced, remain commercially unviable to grow vertically with current technology.

Industry analysts generally view vertical farming as a complement to, rather than a replacement for, conventional agriculture in the foreseeable future. Its strongest near-term role, most agree, lies in supplying fresh, perishable produce to dense urban populations with minimal transport distance and associated spoilage, rather than in replacing the vast majority of global food production, which remains dependent on conventional field agriculture for the foreseeable future.