Academic Reading: 3

Vertical Farming and the Future of Urban Food Production

As cities continue to expand, agricultural land near urban centres is increasingly converted into housing and commercial development, pushing conventional farming further away and adding to the transport emissions food must generate before reaching a table. Vertical farming has emerged as one response: rather than spreading crops across open fields, vertical farms stack layers of plants inside climate-controlled buildings, sometimes within cities themselves, growing food remarkably close to the people who will consume it.

Most vertical farms rely on hydroponic or aeroponic systems, in which plant roots receive a nutrient-rich solution rather than soil, alongside LED lighting tuned to wavelengths plants absorb most efficiently, minimising wasted energy. Because temperature, humidity, and light can be precisely controlled indoors, vertical farms typically produce many more harvests per year than an equivalent area of farmland, and use dramatically less water, since nutrient solutions can be recirculated rather than draining away as they would outdoors.

Despite these advantages, vertical farming faces economic obstacles that have caused several prominent ventures to struggle or close entirely. Running lighting and climate control around the clock consumes considerable electricity, and this cost frequently outweighs savings gained from reduced transport and land use, particularly where electricity prices are high. Partly for this reason, most vertical farms concentrate on fast-growing, high-value crops such as lettuce and herbs, rather than staples like wheat or rice, which require far more space and light per calorie to remain commercially viable with current technology.

Looking ahead, some analysts argue vertical farming's prospects will improve as renewable electricity becomes cheaper, since energy costs represent the single largest expense for most operations. Researchers are also investigating whether grain varieties might eventually be bred to thrive under vertical farming conditions. Until such developments mature, most analysts view vertical farming as a valuable complement to, rather than a replacement for, conventional agriculture.

練習問題

  1. According to the passage, why has vertical farming emerged as a response to urban expansion?

    • Because farmland is disappearing near cities, pushing conventional farming further away and increasing transport distance and emissions
    • Because governments have banned all farming within city limits
    • Because consumers have stopped wanting fresh vegetables
    • Because vertical farming requires no electricity at all

  2. According to the passage, what allows vertical farms to use dramatically less water than conventional farms?

    • They are located exclusively in regions with high rainfall
    • They only grow crops that require no water whatsoever
    • They rely entirely on rainwater collection systems
    • Nutrient solutions can often be recirculated rather than draining away as they would outdoors

  3. According to the passage, why do most vertical farms grow leafy greens rather than staple crops like wheat?

    • Staple crops cannot survive indoors under any conditions
    • Staple crops are not sold in cities
    • Staple crops require far more space and light per calorie produced to remain commercially viable with current technology
    • Leafy greens are the only crops legally permitted indoors

  4. According to the passage, what is described as the largest expense for most vertical farming operations?

    • The cost of hiring agricultural labourers
    • The cost of transporting produce to market
    • The electricity required for lighting and climate control
    • The cost of land near city centres

  5. According to the final paragraph, what is the author's overall view of vertical farming's likely future role?

    • It is likely to remain a valuable complement to conventional agriculture rather than replace it, at least for now
    • It will replace conventional agriculture only for growing wheat and rice
    • It will completely replace conventional agriculture within a few years
    • It has no realistic future and will disappear entirely

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