Questão de Agronomia e Ciências Agrárias

Agriculture and fisheries are closely linked to climate, making them vulnerable to changes in temperature, CO2 levels, and extreme weather. While increased temperature and CO2 can enhance some crop yields, this depends on factors like nutrient levels, soil moisture, and water availability. More frequent droughts and floods could challenge food production and safety, while warming waters may shift fish habitats, disrupting ecosystems. Overall, climate change may complicate traditional methods of farming, livestock raising, and fishing. Crop responses to temperature changes depend on each crop's optimal growth temperature. Warmer conditions might benefit certain crops or enable the cultivation of new ones, but yields decline if temperatures exceed a crop's threshold. Increased CO2 can enhance plant growth under controlled conditions but may be offset by water, nutrient, and temperature constraints. Additionally, elevated CO2 reduces the protein and nitrogen content in crops like soybeans and alfalfa, lowering their quality and diminishing the forage value for livestock. Extreme weather events, such as floods and droughts, can harm crops and reduce yields. For example, high nighttime temperatures in 2010 and 2012 lowered U.S. corn yields, while premature budding caused $ 220 million in losses for Michigan cherries in 2012. Rising summer temperatures may also dry soils, complicating drought management. Increased irrigation could help, but reduced water availability might limit its feasibility. Climate change also favors weeds, pests, and fungi, which thrive in warmer, wetter conditions with higher CO2 levels. This could expose crops to new threats and increase farming costs. U.S. farmers already spend over $ 11 billion annually on weed control, and these challenges are likely to grow as weed and pest ranges expand. While rising CO2 stimulates plant growth, it also lowers the nutritional value of major crops like wheat, rice, and soybeans by reducing their protein and mineral content. This poses a potential risk to human health. Additionally, increased pest pressure may lead to higher pesticide use, further impacting health and reducing pesticide effectiveness. Climate change, therefore, presents multifaceted challenges to food production, nutrition, and ecosystems. Internet:<climatechange.chicago.gov> (adapted). Based on the text above, judge items below.