長文読解（人文系・自然科学系の文章）- 問題29

Urban vertical farming represents a revolutionary approach to agriculture that addresses the growing challenges of food security in densely populated cities. This innovative method involves cultivating crops in vertically stacked layers within controlled indoor environments, typically using hydroponic or aeroponic systems instead of traditional soil.
The advantages of vertical farming are numerous and significant. First, it requires 95% less water than conventional agriculture through precise nutrient delivery systems. Second, crops can be grown year-round regardless of weather conditions, potentially yielding up to 390 times more produce per square foot than traditional farming. Additionally, vertical farms eliminate the need for pesticides and herbicides, producing cleaner and safer food.
Despite these benefits, vertical farming faces substantial challenges. The initial investment costs are extremely high, often requiring millions of dollars for setup. Energy consumption is another major concern, as LED lighting systems consume significant electricity to replace natural sunlight. Critics argue that the current energy requirements make vertical farming environmentally questionable.
Nevertheless, technological advances continue to improve efficiency and reduce costs. As urban populations are projected to reach 68% of the global population by 2050, vertical farming may become an essential component of sustainable urban food systems.