| 1. | The largest and perhaps only real threat to sustainable agriculture comes from unchecked population growth and the resulting downstream effects such as changes in the climate , soil erosion , soil salinization , and soil nutrient depletion 持续农业所面临的最严重的威胁是无限制的人口增长以及随之带来的气候变化、土壤侵蚀、土壤盐渍化以及养分耗竭。 |