What are the sources and sinks that impact the amount of dissolved nutrients present at the surface of the oceans? (Remember: nutrients are dissolved ions like nitrates and phosphates the building blocks of cells which heterotrophs get from their food but which autotrophs must pull from the water if they are to grow.) Nutrient (include Nitrate) SOURCES Nutrient (including Nitrate) SINKS 6. In the blank map below based on known sources and sinks use colored pencils to sketch what you would expect to be the global variation in nitrates (or nutrients in general). BLUE/PURPLE = low | GREEN | YELLOW medium ORANGE 1 RED = high IN ?
