From big to small
This landscape unit combines terrestrial and aquatic ecosystems, and is delineated by topography or landforms, encompassing the entire area of land draining into a stream, river or lake.
What is watershed or catchment?
Since the 1950s, humans have become increasingly reliant on this source of phosphorus to grow crops. It is a limited resource that may run out in the next few decades.
Mined phosphate rock.
These two habitat zones separate lake habitat horizontally and are defined by where 1% of light does and does not hit the bottom.
What are littoral and pelagic zones?
Differences in this factor between water layers causes stratification of lakes.
What is density?
Riparian buffers, constructed wetlands, cover crops, stormwater controls, enhanced WWTPs, and bans on phosphorus in detergents are all examples of this primary approach for reducing eutrophication in lakes.
What is external nutrient load reduction?
This concept helps classify streams based on their position within a stream network.
What is stream order?
Nearly 50% of the nitrogen found in human tissues originated from this source. It is an industrial process that converts N2 gas and hydrogen to ammonia and is the primary way in which humans get nitrogen to grow food. The carrying capacity of the world would be limited to 4 billion humans without this process.
What is the Haber-Bosch process?
Production in this vertical zone defined by < 1% of light is primarily driven by heterotrophic organisms and processes that break down and respire organic matter. This is in contrast to the euphotic zone which is characterized mainly by primary autotrophic production in the form of phytoplankton.
What is aphotic zone?
This layer is the uppermost and warmest layer (also called the mixed layer) of a lake that experiences density stratification induced by seasonal warming at the lakes surface. It is delineated as an isothermal layer between the surface and where a thermocline or temperature gradient begins to form with depth.
What is the epilimnion?
This treatment targets internal loading of phosphorus in lakes by binding dissolved phosphorus and forming insoluble flocs that settle on lake sediments. Rapid results but temporary (5-15 years) solution.
What is Alum treatment?
This habitat type within a stream reach typically consists of shallow depth, fast flow, coarser substrates (gravel, cobble, boulders). It is well oxygenated and an important habitat for aquatic insects and small fish.
What is a riffle?
Increased fertilizer production from the Haber-Bosch process and mining of phosphate rock leads to runoff of excess nitrogen and phosphorus from landscapes into freshwater ecosystems. This diffuse source of excess nutrients is an example of _______ pollution.
This key water quality factor which represents the amount of light that is scattered by material in water can alter lake habitat zone extents based on its influence on light penetration.
What is turbidity?
This cold, isothermal bottom layer of a stratified lake does not support photosynthesis due to lack of solar irradiance. Heterotrophic production in this layer may develop partial or complete depletion of dissolved oxygen as stratification time increases.
What is the hypolimnion?
This approach to managing eutrophic lakes involves reducing planktivores by increasing piscivores to increase top-down control of nuisance algae by zooplankton.
What is biomanipulation?
This process leads to alternating bank erosion and depositional processes that form alternating pool and riffle habitat with intervening glide habitat in streams and rivers.
What is stream meandering?
Increased food production allows for greater human population size which increases the need for wastewater treatment. Discharge of water from wastewater treatment plants into rivers and lakes is an example of ___________ pollution?
What is point source?
This zone extends a few centimeters above and below the bottom of a lake, including the upper layer of sediments.
What is benthic zone?
Dissolved N2 gas building up in the hypolimnion is evidence for this microbial process that reduces NO3 to N2 under anoxic conditions.
What is denitrification?
This manipulation attempts to limit inflow of nutrient rich waters to lakes by installing structures that move water into holding structures such as wetlands or manage water levels during macrophyte recruitment windows.
What is hydraulic isolation or hydrological manipulation?
This measurement represents the volume of water passing a specific point per unit time. It's units are (m3 S-1).
What is discharge?
Nutrient enrichment of freshwater ecosystems can lead to high algal production, often dominated by cyanobacteria which can produce toxins and odors. These events are often referred to as HABs which stands for _____ ______ _____.
What is harmful algal blooms.
Primary production shifts from _________ to ________ as zones transition from littoral to pelagic habitats.
What is macrophyte/periphyton to phytoplankton?
Dissolved PO4 builds up in the hypolimnion during stratification due to these processes acting on inorganic and organic P.
What is dissolution of FePO4 precipitates and mineralization of organic P?
These two biomanipulation approaches are connected because one reduces resuspension of sediments and success of the other is dependent on sufficient water clarity/light availability.
What is removal of bottom-feeding fish and macrophyte reintroduction?