AUD 2b Lect #1 (pond calendar/types, water chemistry)

What are some characteristics of a winter pond

• slower metabolism, decomposition, fish movement

• ice formation (can cause oxygen depletion)

• fish kills are common without aeration

Draw winter stratification and label where ice, warm water, and cold water are

*ADD IMAGE

At what temperature is water most dense

39 F

What are some characteristics of a spring pond

• fish become active (60-65F)

• spawning/hatching/bacterial gill disease

• mixing of water temps (turnover)

• increase oxygen

• clear water

• increase aquatic plant growth

What are some characteristics of a summer pond

• fast metabolism, plant/algae growth, decomposition

• thermocline develops

• increased photosynthesis (altered pH)

• ammonia can build up

Draw summer stratification and label the epilimnion, hypolimnion, cold water, warm water, and thermocline

*ADD IMAGE

What are some characteristics of a fall pond

• slowing metabolism, growth

• decomposing plant growth

• mixing of the water (turnover)

• lots of oxygen

What are the 3 ways ponds are constructed and what do they require in their soil

• clay! (helps retain water and not leak)

• excavated

• embankment

• combination

What measurements are considered in a recreational pond and what are they

• slopes are 3:1 (minimize littoral zone, allows spawning)

• if fishing, 25%+ should be 8+ ft deep

Describe a recreational pond overflow

• slanted pipe

• anti see collars (prevent water migration)

• has an emergency overflow

Describe a stormwater pond overflow

• sophisticated to allow specified release of water

What is a stormwater pond overflow purpose

• treat water by collecting runoff from impervious surfaces

• allows for sedimentation/precipitation of nutrients/pollutants

What are some water sources for ponds

• watershed

• stream

• stormwater

• well

• spring

What is dissolved oxygen

how much oxygen gas is in the water

What is pH

measure of how acidic (<5.3) or basic (>9.5) water is

What is alkalinity

measures carbonate hardness and represents buffering capacity (how well water can rebound when an acid/base is added) of water

• high alkalinity will maintain a stable pH

What is hardness

measure of dissolved calcium and magnesium in water

Describe the nutrient quality, water clarity, and growth-likelihood for an oligotrophic pond

• low nutrient

• high clarity

• low growth

Describe the nutrient quality, water clarity, and growth-likelihood for a mesotrophic pond

• mod nutrient

• mod clarity

• mod growth

Describe the nutrient quality, water clarity, and growth-likelihood for an eutrophic pond

• high nutrient

• low clarity

• mod-high growth

Describe the nutrient quality, water clarity, and growth-likelihood for a hypereutrophic pond

• very high nutrient

• very low clarity

• high to very high growth