Nutrients from sewage and agricultural fertilizers also help algae grow .

污水和农业肥料中的营养也可以导致海藻大规模增长。

It can also seep in from some pesticides and fertilizers .

同样它们也可以通过杀虫剂和肥料渗透进食物。

But some of the vegetables were grown with chemical pesticides and organic fertilizers . Others complied with danish guidelines for organic farming .

但有的蔬菜在生长中用了化学杀虫剂和有机肥料，另一些则遵循着丹麦有机种植准则。

So food grown without conventional chemical pesticides , fertilizers and lacking additives is popular despite the fact that it costs as much as 50 percent more .

因此，不用传统化学农药、肥料和少量添加剂的农作物种植很受欢迎，尽管事实上它的成本差不多要多50%以上。

So he and his colleagues tested a range of chemicals found in fertilizers , including nitrate , ammonium and urea , to determine their effects on the algae .

他和同事们研究了肥料中的一系列化学物质，包括硝酸盐，铵和尿素，观察他们对海藻的影响。