ENV SP Natural World & Ecology 2 — Questions and Answers
Question 1: Which Envision credit category directly addresses the protection of wetlands and riparian buffers during infrastructure construction?
- Quality of Life
- Natural World (Correct answer)
- Resource Allocation
- Leadership
Correct answer: Natural World
The Natural World credit category in Envision includes credits focused on protecting wetlands, floodplains, and riparian areas from disturbance.
Question 2: What is the primary ecological function of a riparian buffer zone adjacent to a stream?
- Increasing water temperature for aquatic species
- Filtering runoff pollutants and stabilizing stream banks (Correct answer)
- Providing urban green space for recreation
- Channeling stormwater to reduce flooding
Correct answer: Filtering runoff pollutants and stabilizing stream banks
Riparian buffers intercept sediment and nutrient runoff from uplands and their root systems physically stabilize streambanks.
Question 3: Under the Envision framework, a project that restores previously degraded habitat beyond its original footprint would likely earn credit under which performance level?
- Improved
- Enhanced
- Superior
- Restorative (Correct answer)
Correct answer: Restorative
The Restorative performance level in Envision is achieved when a project restores ecological function or habitat beyond pre-project conditions.
Question 4: Keystone species are important to ecosystem management because they:
- Are the most numerous species in the community
- Have a disproportionately large effect on ecosystem structure relative to their abundance (Correct answer)
- Occupy the highest trophic level in the food web
- Are exclusively native to a single geographic region
Correct answer: Have a disproportionately large effect on ecosystem structure relative to their abundance
Keystone species exert outsized influence on ecosystem structure and function relative to their biomass, so their loss can trigger dramatic community shifts.
Question 5: Which ecological concept describes the process by which a disturbed ecosystem gradually returns to its climax community over time?
- Ecological resilience
- Ecological succession (Correct answer)
- Trophic cascade
- Competitive exclusion
Correct answer: Ecological succession
Ecological succession is the sequential replacement of species communities in a habitat following a disturbance until a stable climax community is reached.
Question 6: When an infrastructure project is sited in a floodplain, the Envision framework primarily encourages designers to:
- Install larger culverts to convey floodwaters faster
- Avoid the floodplain or restore natural floodplain function (Correct answer)
- Harden stream channels with riprap to prevent erosion
- Increase impervious surface to redirect runoff
Correct answer: Avoid the floodplain or restore natural floodplain function
Envision's Natural World credits favor avoiding sensitive areas like floodplains and, when unavoidable, restoring natural hydrological and ecological function.
Question 7: A project team uses a habitat equivalency analysis (HEA) to determine mitigation requirements. What does HEA quantify?
- The economic value of lost ecosystem services
- The area and time of ecological service losses and gains to achieve no net loss (Correct answer)
- The number of species displaced by a project
- The carbon sequestration potential of replacement plantings
Correct answer: The area and time of ecological service losses and gains to achieve no net loss
Habitat Equivalency Analysis calculates the debit of ecological services lost and the credit of compensatory mitigation needed over time to achieve no net loss.
ENV SP Natural World & Ecology 2
Which Envision credit category directly addresses the protection of wetlands and riparian buffers during infrastructure construction?