CES Ecological Risk Assessment & Biodiversity 2

Question 1

In ERA, which endpoint type directly measures effects on individual organisms rather than populations or ecosystems?

Accepted Answer

Measurement endpoint

Answer

Measurement endpoints are quantifiable ecological characteristics used to evaluate exposures and effects, measured at the individual organism level.

Question 2

The Simpson's Diversity Index (D) is calculated as D = 1 - Σ(n/N)². A value of D closer to 1 indicates:

Accepted Answer

High diversity with many equally abundant species

Answer

Simpson's Index approaches 1 as diversity increases, reflecting more species with more equal abundances.

Question 3

Which U.S. EPA guidance document provides the primary framework for conducting ecological risk assessments?

Accepted Answer

EPA/630/R-95/002F (Guidelines for ERA)

Answer

EPA's 1998 Guidelines for Ecological Risk Assessment (EPA/630/R-95/002F) is the primary framework document for ERA in the U.S.

Question 4

A species exhibits a Type III survivorship curve. This means mortality is:

Accepted Answer

Highest among juveniles with survivors living long lives

Answer

Type III survivorship curves show high early mortality (juveniles) but low mortality rates for survivors, typical of many fish, insects, and plants.

Question 5

In population viability analysis (PVA), the minimum viable population (MVP) is defined as the population size needed to ensure:

Accepted Answer

A 95% probability of persistence for 100 years

Answer

MVP typically represents the minimum population size with a 95% chance of persistence for 100 years, accounting for demographic and environmental stochasticity.

(CES) Certified Environmental Scientist Practice Test

(CES) Certified Environmental Scientist Practice Test

CES Ecological Risk Assessment & Biodiversity 2