Stream water chemical parameters for Tutuila Island, American Samoa, Polynesia
Bardi E, Fanolua S, van Houte-Howes K, Wade LM, Vargo AM, Vargo DL. 2006. Stream water chemical parameters for Tutuila Island, American Samoa, Polynesia
Little information exists on the chemical and physical attributes of freshwater resources in American Samoa to aid environmentalists, policymakers, and regulators in making sound decisions concerning their preservation and protection. To help fill this void we measured pH, conductivity, turbidity, temperature, dissolved oxygen, calcium, magnesium, potassium, sodium, reactive phosphorus, ammonium-N, and nitrate-N levels for 44 perennial streams on Tutuila Island at monthly intervals for two years. Based upon phosphorus and nitrogen levels, we partitioned the streams into three levels of human impact. A one-way analysis of variance by level gave significantly different medians for all parameters except pH and turbidity. Only seven streams possibly comply with current water quality standards for phosphorus and nitrogen for fresh surface waters, while none comply with the standard for turbidity. For streams affected only by agrarian and residential activities, monitoring reactive phosphorus and conductivity alone may be sufficient to discern changes in the intensity of human impact.