Wetlands Ecology Midterm

Environmentalism

A concern for the environment. Not necessarily based on science, but rather aesthetic, moral, pragmatic, or religious beliefs. It is a form of activism, how we behave.

Environmental Science

The scientific study of the influence of human actions on natural processes

Environmental Studies

Identical to environmental science, except in the context of academia. In academia, it is more centered around humans than environmental science is. You cannot have an environmental studies question without it also being an environmental science question

Ecology

The study of the distribution of species and how they interact with the environment

Wetland

a habitat area that is either periodically or permanently inundated by surface or ground water, and supports vegetation adapted for life in saturated soils (hydrophytic)

Wetlands Ecosystem functions

Wetlands function as ecotones between terrestrial and aquatic systems and are important connections between them. 

Wetlands Ecosystem Services

They prevent floods, improve water quality, and provide habitat for many animals. They are vital to >33% of species listed as endangered or threatened in the U.S. They are essential for the recruitment of fish and shellfish.

Ecotone

transition between one habitat type and another, often containing species from both. Wetlands function as ecotones between terrestrial and aquatic systems

Succession

The natural, gradual process that ecosystems change and develop over time

Costal Wetlands

Influenced by tidal fluctuation in water-level. Often a saline environment. Cover 3.2×10⁶ha in the U.S. 

Inland wetlands

Non-tidal. Generally, freshwater environment. Cover 107×10⁶ ha in the U.S.

Marshes

Wetlands characterized by emergent herbaceous plants (no trees)

Swamps

Forested wetlands

Tidal salt marshes

Protected coastal areas. Salt adapted organisms. The majority are on the east coast

Tidal freshwater marshes

Inland from tidal salt marshes but still influenced by tides. Difficult to define

Mangrove Swamps

Protected. Warm coastal areas. Primarily Florida

Tidal freshwater marshes and swamps

Inland rom tidal salt marshes but still influenced by tides. Difficult to define.

Riparian wetlands

Adjacent to rivers and streams. Periodic flooding. Often dry for significant parts of the year

Freshwater marshes

emergent aquatic plants. Low peat accumulation

Peatlands

Bogs, fens, swamps. Peat accumulating. Generally i glaciated areas.

Bogs

No inflows/outflows (H₂O from precipitation). Peat accumulating. Acidic environment. Acid tolerant species such as sphagnum mosses. 

Peat

Decomposing fibrous plant organic matter. Identifiable plant forms.

Fens

Marsh like species. Peat accumulating. Has some drainage to/from surrounding soils. Not acidic because of minerals in the water.

Boreal Swamps

Generally Black Spruce (in North America) with acidic peat soils (mosses)

Ground Water

Water that exists beneath the surface of the earth

Water Table

Upper level of the groundwater in the zone of saturation

Surface Water

Water that is on Earth’s surface. (E.g. stream, river, lake, or reservoir)

Transpiration

The process where plants release water vapor into the atmosphere through their stomata

Condensation

The atmospheric process where water vapor becomes liquid water 

Infiltration

The natural process of water on the soil surface soaking into the ground, replenishing soil moisture and groundwater, and becomming a crucial part of the hydrologic cycle

Hydraulic conductivity

A measure of how easily water can pass through soil or rock: 
high values indicate permeable material through which water can 
pass easily; low values indicate that the material is less permeable. Influenced by hydraulic conductivity (k), cross sectional area of groundwater (Aₓ), and hydraulic gradient (slope of water table) (s) (Darcy’s Law)

Hydroperiod

The pattern of water-level within a wetland ecosystem

Pool

Reservoirs of matter or energy within a system

Flux

Movements of matter or energy in and out of a system

Interception

When something blocks from getting somewhere. E.g. interception of rainfall from a canopy.

Net ecosystem production

The toral amount of carbon an ecosystem captures during photosynthesis (GPP) minus the total amount that is released into the atmosphere through respiration by plants, animals, and microbes. A positive net ecosystem production means it it capturing more carbon than is released which helps climate change. GPP-Ra-Rh

Surface flow

water flowing on the surface

Hydraulic conductivity

how easily water moves through a material

Darcy’s law

K .A_x. s

K (hydraulic conductivity) A_x (the material that water is moving through) s (slope)

Potential ET (evaporation/transpiration)

The amount of water that under ideal conditions could evaporate

Actual ET

The amount of water that does evaporate

Specific Yield

The description of where the substance is on the scale of “porosity”

Porosity

how much space is between a substance (concrete, low, sand, high)

Biogeochemistry

The study and transformation of chemicals within an ecosystem. There is biology, chemistry, and geology going on within every system

Hydric soils

Soils that are saturated long enough to develop anaerobic conditions. Soils with little oxygen in it. 

Mineral soils

Soils with low organic content and dominated by sand, silt, and/or clay.

Organic soils

Solid with high content of decomposing biological material: high carbon content. High carbon content doesn’t always mean low oxygen

Saprists

aka muck. Organic soils that are highly decomposed. You generally can’t identify plant parts in this soil

Hemists

a.k.a peaty muck. Intermediate between fibrist and saprist soils. Intermediate broken down material.

Fibrists

aka peat. Fibrist means peat, interchangeable words.

Oxidation

loss of electrons (leo)

Reduction

gain of electrons (ger, gain)

Reduction-oxidation potential

coupled oxidation/reduction reactions. Co-occurring. When one thing loses electrons (oxidation), another gains electron (reduction). Dependent on the available energy source (organic material), the microbes in the soil, and a restriction on the resupply of oxygen

Nitrogen mineralization

(aka Ammonification). A redox reaction. Occurs in aerobic or anaerobic soils. Ammonium diffuses upwards due to concentration gradient. Can be immobilized by soil particles.

Nitrification

a redox reaction. Ammonium to nitrate plus some released energy. Nitrate diffuses downward because of the concentration gradient, and it is not immobilized

Ammonification

Denitrification

the redox reaction that uses nitrate. Occurs only in anerobic conditions.

Sulfate reduction

happens within Marine wetland ecosystems because of sulfur. Diffuses upward because of concentration gradient (not a lot on atmosphere). Happens in decomposition, the gas is toxic to plants. More in marine wetlands.

Carbon reduction

CO₂ compounds used as electron acceptors (loses oxygen). More in freshwater wetlands

Oxidants

loose electrons in the process of providing an oxygen in the reaction

Compare and contrast environmental science and ecology.

Ecology is about organismal interactions and distributions, while environmental science studies the effects of human actions on these interactions, distributions, and other natural processes. Hence, these terms are not interchangeable. You can have research that falls under the field of ecology, but not environmental science. For example, you can study hydrology without looking at the effect that humans have on it: studying sparrows and the role of water levels depending on the wet/dry season on the fecundity of that species. (this is purely ecological and has nothing to do with human actions). You can also have an environmental science project that is not ecological—

What is a wetland and how would you define it?

A wetland is a habitat that is periodically or permanently inundated by surface or ground water and supports vegetation adapted for life in saturated soils. They serve as ecotones between terrestrial and aquatic systems. 

What are examples of wetland services? (services vs functions).

Functions are irrespective of what human needs. Photosynthesis is a function, oxygen is a service. Examples of wetland services include preventing floods, improving water quality, and providing habitat for many plants and animals.  

What do wetland ecologists' study?

The way species are distributed within wetlands, how those species interact with their environment, and the role they play in the transformation and movement of energy and matter 

What factors do we need to consider when talking about ecosystems?

Everything

What are some values wetlands hold?

They prevent floods, improve water quality, and provide habitat. They are vital to over 33% of endangered or threated species in the US.  

How does succession (changes in community composition) influence ecosystem productivity?

The time after succession, productivity increases after you get it from old growth systems.

What is the ecological hierarchy, and what does each level study?

Physiological, population, community, ecosystem, landscape, biosphere.  

What is an ecotone and how does it influence diversity?

An ecotone is a transitional zone between two ecosystems where they meet and overlap. They influence biodiversity by providing habitat for a vast number of different species and even edge species. 

What are the major fields of ecological study?  

Physiological, populations, communities, ecosystems, biosphere 

What is the difference between primary and secondary succession? 

Primary succession is the establishment of a mature community including soil formation. Early, mid-, late successional species. Generally slow, up to 1000’s of years. Secondary succession is the re-establishment after a disturbance (such as logging, farming, fire, hurricane or tornado damage). Fast, on the order of 200 years. Secondary succession is faster because soil is already present (which contains essential nutrients, microbes, and seeds).  

Explain nitrogen fixation, and why it is important to the nitrogen cycle.

It is the process of converting atmospheric N2 into usable nitrogen such as ammonia. This process can happen physically (lightning) or biologically (via bacteria). It is important in oligotrophic environments so organisms can use nitrogen instead of oxygen.  

Explain the carbon cycle. 

 It is driven by photosynthesis. The plants take up carbon (photosynthsis, gpp total carbon taken up), and put it into organic molecules, breaks it down and consumes oxygen when doing it, then releasing it. Respiration take carbon out of atmosphere. Change in carbon content in plant is photosynthesis minus respiration. (NPP, change in carbon content) 

Explain the hydrologic cycle.

The cycle is the continuous movement of water above and below the earth’s surface. It includes processes such as precipitation, infiltration, groundwater flow, surface flow, evaporation, evapotranspiration, and condensation. The 2 energy drivers of the hydrologic cycle are solar radiation (drives evaporation and condensation) and gravity (causes water to flow).  

Explain the phosphorus cycle. know what each step does in the cycle, and how it influences in the ecosystem/why it is important.* 

Precipitation

rainfall

Infiltration

when water moves from the surface into the soil and into subsurface rock.

Groundwater flow (in the hydrologic cycle)

movement of subsurface water within an aquifer.  

Surface flow

where precipitation (rain/snow, etc) falls on land and flows over the surface of the earth as runoff and collects in rivers, streams, etc.  

Evaporation

when liquid turns into gas as water vapor

Condensation:

when gas (water vapor) condenses into liquid water, forming clouds and fog. Precursor for precipitation.

Transpiration:

when plants absorb water through their roots and release it into the atmosphere as water vapor from their leaves.  

Evapotranspiration

the combined term used when evaporating water from soil, water bodies (evaporation), and plant leaves (transpiration) 

What is groundwater flow influenced by? 

Influenced by hydraulic conductivity (k), cross sectional area of groundwater (Aₓ), and hydraulic gradient (slope of water table) (s). Darcy’s Law: G = k Ax s 

Why did the eggplants die? 

The flooded eggplants died because the anaerobic conditions in the soil caused the roots to die and rot. The eggplants were unable to take up enough water and nutrients from their roots. Under permissible conditions, water is conducted from the roots, through the xylem, to the leaves. The stomata opens when guard cells fill up with water, allowing for the release of water vapor during transpiration. The opening of the stomata also allows carbon dioxide to enter the leaf and allows oxygen to exit. However, when water is unavailable, stomatal conductance and transpiration decline because the stomata are unable to open.  

How are PET and AET measured? 

How does succession influence ecosystem productivity? 

What does this equation stand for and how is it used? 

• ΔV = Pn + Si + Gi + Ti - ET – So - Go – To 

ΔV (change in volume) Pn (net precipitation) Si/So (Surface water inflow/outflow) Gi/Go (groundwater inflow/outflow) Ti/To (Tidal inflow/outflow) ET (evapotranspiration)  

-Ti and To are not measured for all wetlands systems 

What does this equation stand for and how is it used? G=K Ax S

Hydraulic conductivity (k), cross sectional area of groundwater (Aₓ), and hydraulic gradient (slope of water table) (s). used to measure groundwater flow

What are soil/wetland redox reaction dependent on?

Available energy source, microbes, and a restriction on the resupply of oxygen. Deeper soils mean lower redox reactions, it is harder for the microbes to get the electrons they need to metabolize. It is variable and best used as a relative soil status. Changing over space/time. Any measurement you get is relative. Microbial activity, hydrology, and diffusion of oxygen in the soil.  

Ground Water Flow

Water under the ground

The Munsell notation identifies color by the use of what three variables?

Hue, Value, and Chroma

Hue

the dominant spectral (rainbow) color; that is whether the color is yellow, red, green, or mixtures such as yellow-red

Mixtures are identified numerically according to____?

The amount of yellow or red used to produce the mixture. 5YR is an equal mixture of red and yellow. As the number increases, the amount of the first color (Y, yellow) increases and as the number decreases, the amount of the second letter color (R, red) increases

_____ and ______ are terms that refer to how the hue is modified by the addition of grey to the pure color (hue)

Value and Chroma

Value

a property of the grey color that is being added to the hue

How is Value made?

A particular grey (value) is made by mixing a pure white pigment (10) with a pure black pigment (0). If equal amounts of black and white pigments are mixed, the value is equal to 5. If more black pigment is used than white pigment, then the value is less than 5. If more white than black pigment is used, then the value is greater than 5.

Chroma

the amount of pure hue that is mixed with a grey of pure hue that is mixed with a grey of a particular value to obtain the actual color.

How is chroma made?

A chroma of 1 would be made by adding one unit of pure hue to a certain amount of grey. A chroma of 5 would contain 5 units of pure hue to that amount of grey. The lower the chroma, the greyer the color.

Color Names Vs. Munsell Notation

Color names are less precise, but convey a general concept of the color of the soil. Munsell notation is more precise and is standardized so that soil scientists in different countries will have no difficulty in communicating information about soil color.