TOEFL統合ライティング

📖 読解文章

The concept of 'sustainable intensification' has been proposed as a solution to meet global food demand while reducing environmental impact. This approach suggests that by increasing crop yields on existing farmland through advanced technologies, we can avoid clearing more land for agriculture. Proponents argue three main points. First, high-yield varieties and precision farming can double production per hectare, thereby sparing forests and grasslands from conversion. Second, modern irrigation and fertilizer management reduce water waste and nutrient runoff, mitigating pollution. Third, genetically modified crops that resist pests and droughts reduce the need for chemical pesticides and stabilize yields under climate stress. Thus, sustainable intensification is presented as a win-win strategy for food security and conservation.

🎧 リスニング講義

The lecture challenges each point in the reading. First, while high-yield varieties boost output, they require intensive inputs like synthetic fertilizers and fossil fuels, which increase greenhouse gas emissions and soil degradation. The reading overlooks that 'spared' land is often of poor quality or not suitable for conservation, so biodiversity loss continues. Second, improved irrigation and fertilizer management can reduce waste, but in practice, smallholder farmers in developing countries lack access to these technologies. Even when adopted, the energy for pumping water and producing fertilizers adds to carbon footprints, offsetting environmental gains. Third, genetically modified crops may reduce pesticide use, but they encourage monoculture, which reduces genetic diversity and increases vulnerability to new pests. Moreover, herbicide-resistant crops have led to overuse of glyphosate, harming beneficial insects and soil microbes. Therefore, the lecture concludes that sustainable intensification is not a simple solution and may even exacerbate environmental problems if implemented without considering socio-economic and ecological contexts.