lehuynh (version 0.1.1)

tsi: Calculate TSI (Trophic state index)

Description

Calculate TSI. TSI range: 0 - 100.

Usage

tsi(x, type = c("chla", "TP", "TN", "SD"))

Value

a numeric value.

Arguments

x

numeric object

type

type of variable used to calculate TSI. See Details for more information.

Details

Trophic state classification (Carlson, 1996)

• <30-40, Oligotrophy

• 40-50, mesotrophy

• 50-70, eutrophy

• 70-100, hypereutrophy

Type of variable used to calculate TSI:

• SD: Secchi depth, meter

• chla: chlorophyll, ug/L or mg/m3

• TP: total Phosphorus, ug/L or mg/m3

• TN: total Nitrogen, mg/L

Carlson (1977): TSI-SD, TSI-Chla, TSI-TP

USEPA (2000): TSI-TN

References

Carlson, R. E. (1977). A trophic state index for lakes. Limnology and Oceanography, 22(2), 361-369.

Carlson, R. E., & Simpson, J. (1996). A Coordinator's Guide to Volunteer Lake Monitoring Methods. North American Lake Management Society, 73-92.

USEPA. (2000). Nutrient Criteria Technical Guidance Manual: Lakes and Reservoirs, 42-44.

Examples

chla <- c(0.12, 0.34, 0.94, 6.4)

tsi(chla, type = "chla")

tsi(chla, type = "TP")