Eco Core 5 Exam

systems are defined by what 3 things

purpose of function

elements

interactions

what 3 things can flow into, out of, and within systems

energy

information

material

why is a primary producer an example of autocatalysis

plants build large structures to get more sunlight in the form of leaves, getting more sunlight leads to ability to build more leaves; positive feedback

what is ecological engineering and how is it applied

ecological engineering focusses on design, monitoring, and constructing ecosystems by integrating the natural environment and natural principles for the benefit of humans and ecosystems; typically aims for to replicate the self designing aspects of an ecosystem

applied by seeking to implement natural processes into engineered structures instead of using traditional or gray engineering approaches

draw a systems diagram for a forest system

what are the symbols in a system diagram

rectangle- system boundary

circle- source (sun)

round pentagon- storage

flag- interaction

bullet (has flag (producer) and round pentagon (biomass) inside)- producer

hexagon (has flag (consumer) and round pentagon (biomass) inside)- consumer

diamond- transaction

sideways star- switching action where flows are interrupted or initiated

box- misc

conventional vs. wetland wastewater treatment and how to know which is more appropriate

conventional: fossil fuel intensive, gray infrastructure heavy, less land demand, works year around

wetland: land intensive, natural system based, little human intervention once designed, low fossil fuel requirement, subject to seasonal changes

more appropriate: land availability, temperature changes, and nutrient removal necessary determines which is more appropriate

FWS, HSSF, FV and pros and cons

FWS (free water surface wetland)-

pros: lower construction and operating cost, higher flow rates, low clogging, high quality habitat, good at dealing with pulses, high sediment loading

cons: low oxygen levels, seasonal operation, pathogen risk, best for polishing, mosquitos

HSSF (horizontal subsurface flow wetland)-

pros: low pathogen risk, low mosquito risk, operate year round

cons: high construction cost, low flow rates, clogging, low quality habitat, variable oxygen levels, not good with pulses

FV (free vertical flow wetland)-

pros: low pathogen risk, low mosquito risk, higher oxygen levels, can deal with pulses better than HSSF, operate year round

cons: high construction cost, low flow rates, risk of clogging, low quality habitat

what is hydraulic loading rate and its dimensions

length/time

hydraulic loading rate is the volume of water that can pass through/over a surface area over a set amount of time (area of water added per time)

if wetland inflow doubles, nominal residence time is

halved

Which pollutant has the higher mass loading rate?

a. Pollutant A: inflow rate = 50 gallons per minute, concentration = 2 g/L

b. Pollutant B: inflow rate = 1200 gallons per minute, concentration = 2 mg/L

pollutant A

Most pollutant removal in wetlands can be described as:

a. First-order

b. Zero-order

c. Second-order

d. Constant

first order

T/F: Wetlands remove most pollutants to values below analytical detection limits.

False

What is the fate of nutrients that are removed in a treatment wetland? What are the processes by which they are removed?

nutrients are uptaken by plants and trapped in the sediment

settling, assimilation, mineralization, nitrification/denitrification, sorption (storage), burial (removal)

what nutrient requires teh most area to remove and is therefore usually the most limiting

phosphorus

what is systems thinking

systems thinking focuses on the interactions, elements, and purpose of functions within a complicated problem/system to try and find ways to solve a problem when looking at it holistically rather than by looking at parts individually

Under what conditions is organic matter decomposition faster: oxic or anoxic? What gases are produced under each condition?

oxic decomposition is faster

oxic- CO₂

anoxic- methane and CO₂

Are wetlands sources or sinks of BOD?

sinks

In what ecosystems would aeolian transport be especially important?

coastal, extremely dry climates (dunes, deserts)

For sewage treatment, what is primary treatment? Secondary treatment? Tertiary treatment?

primary- settling/physical removals of tss bod and particulates

secondary- biological treatment for nutrients (BOD TSS NH4)

tertiary- polishing, filtration, disinfection (TN TP)

Why are wetlands generally very good at removing TSS from wastewater or stormwater?

TSS has low velocity so it settles easily and gets trapped by the wetland plants/bed media efficiently

Name two possible sources of TSS in wetland outflows.

plant matter from the wetland plants themselves, turbidity from natural water flow

Why is restoration so hard to accomplish? And given that, why does it remain a leading conservation tool?

ecosystems are often damaged so badly that it’s very difficult for them to return to a natural state and it is difficult to know the effects of a restorative action on the whole system; enhancing one function may degrade another

still a leading tool because it protects against habitat loss and protects ecosystems after human disturbances, often better than engineered replacements of the system

monetary incentive for ecosystem services

Which ecosystem type is the most valuable per unit area? Which is the most expensive to restore per unit area? Which provides the great rate of return per dollar invested on restoration?

coral reefs and coastal wetlands most valuable

coral reefs most expensive

grasslands (and other forests) greatest ROR

What is a hybrid wetlands treatment system?

a wetland treatment system that uses multiple styles of wetlands to produce anoxic and oxic trains for treatment (ie VF first then HSSF)

What are the main categories of sources of waste water, and their notable characteristics?

municipal- habitat creation, public use, high TN and TP

stormwater- flood control, urban pollutants

industrial- petro, processing water, food processing

agricultural- runoff from poop pesticides etc

Explain why oxic and anoxic treatment systems in series may be the most efficient way to treat waste water.

it allows for nitrification and denitrification to occur, allowing for the complete removal of nitrogen

TN and TP are main wastewater concerns when treating with a wetland

What are the steps in restoring an ecosystem?

assess site

identify methods to stop or reverse disturbance

make project goals

remove disturbance

restore processes/cycles

rehab substrates

restore vegetation

monitor/maintain

Assimilation is when nitrate, nitrite, and ammonium N are taken up by plants. Are these forms organic or inorganic?

inorganic

Compare and contrast restoration, creation, and enhancement

restoration: returning degraded ecosystem to pre existing condition or as close to it as possible

creation: converting one ecosystem to another

enhancement: increasing the functions performed by an existing ecosystem beyond what currently exists

What is the process by which bacteria convert organic nitrogen into inorganic ammonia?

mineralization/ammonification

Under what conditions does nitrification occur?

aerobic

What is the end product of denitrification?

nitrogen gas N2

Why are BOD and nitrogen removal in wetlands more sensitive than TSS and phosphorus to differences in temperature?

nitrogen and decomposition depends on microbes whose metabolism slows in cold temps (biological)

TSS and P are chemical/physical and rely less on temp

Do wetlands remove phosphorus from wastewater?

no they bury phosphorus in soils by building peat or adsorp them to mineral substrate

Holding all other parameters and variables equal:

a. What happens to nitrogen outlet concentration when HLR goes up?

b. What happens to TSS outlet concentration when k goes up?

c. What happens to BOD outlet concentration when C* goes up?

d. What happens to phosphorus outlet concentration when C in goes down?

a. HLR up nitrogen at outlet up

b. k up TSS at outlet down

c. C* up BOD at outlet up

d. Cin down P at outlet down

Holding all other parameters and variables equal, what happens to required wetland size

a. …when HLR goes up?

b. …when k goes up?

c. …when C* goes up?

d. …when Cin goes down?

a. HLR up size down

b. k up size down

c. C* up size up

d. Cin down size down

Given a temperature of 20° C and a median k-value of 15 m/yr for TN, what would affect wetland sizing more:

a. Increasing temperature by 2° C

b. Decreasing k by 50%

c. Doubling Q

decreasing k by 50% and doubling Q

Give two examples of wetland structure and two examples of wetland function that an ecosystem restoration project might seek to restore.

structure: natural surface flow, planting native vegetation

function: nutrient reduction of TN and TP, carbon storage

Contrast ecological restoration and restoration ecology.

ecological restoration is the act of restoring an ecosystem, restoration ecology is the study of it before actually attempting to restore

Which do you think would be easier: restoring a degraded ecosystem or creating a new one from scratch? Why?

creating a new one because there is not as strict of a goal or parameters that must be checked before the fact; there are so many unknown effects to the entire system when trying to restore an ecosystem but creating a new one would have less dire consequences

Why might ecological restoration be considered a disturbance?

the ecosystem has adjusted to the changed conditions and will have to readjust to the restored condition after restoration takes place; restoration efforts can put additional stress on the ecosystem

How does the idea of succession come into play when thinking about ecosystem restoration?

ecologists must consider how an ecosystem will change over time when putting restoration efforts in place; the longevity of the restoration is also dependent on how it can hold up long term to succession

In what ways does increasing impervious surface area affect the watershed water balance?

flashier floods, increased runoff, shorter residence times, greater total runoff volume, higher peak, less infiltration, worse soil quality

Name three ways that urbanization affects streamflows.

greater total runoff volume

higher peak runoff rate

flashier

Why is runoff sometimes referred to as “rainfall excess”? In excess of what?

it is the excess water that cannot infiltrate into the soil or reach a storage

Be prepared to apply the Rational Method and Curve Number Method, and explain what they are.

rational method: runoff flow rate is determined by a runoff coefficient based on land type (Q = CIA)

curve number method: a coefficient based on land type and precipitation that is used to measure runoff volume and initial abstraction volume (S = 1000/CN - 10 ; I = 0.2S ; Q = (P - I)² / (P - I +S))

When seeking to control post-development runoff, the goal is to

a. Match pre-development runoff volume

b. Match pre-development peak flow

c. Both

d. Neither

both

Which approach, LID or GSI, is more associated with MITIGATING the impacts of urban development?

GSI

Which approach, LID or GSI, is more associated with AVOIDING and MINIMIZING the

impacts of urban development?

LID

Name three strategies for MINIMIZNG impervious surfaces in new developments

vegetated swales

narrower streets

more housing density with smaller lots and multiple stories

Name three approaches for AVOIDING, MINIMIZING, and MITIGATING the effect of new development on watersheds

disconnect impervious surfaces

control the runoff source

maximize infiltration, evapotrans, filtration, storage

What are the dimensions of annual mass loading of nitrogen?

gram/m²/year (mass/area/time) or mass/time for total load

Be prepared to estimate changes in annual mass loading before and after development (given appropriate coefficients, rainfall data, and event-mean concentrations).

runoff volume * flow-weighted concentration (mean)