The nutrientsused in ecosystems by living organism operate on? A-open system.
B-closed system.
C-both

multiply it by 5 in order for you to understand i cant give an exact answer.

the wetland preservation movement began in the u.s. in earnest with the clean water act (cwa) of 1972. although not specifically written to protect wetlands, the cwa is comprised of a series of regulations designed to prevent pollutants from contaminating u.s. waters.

want or the answer