Primary Production and Ecosystem Science Flashcards

Sixty vocabulary flashcards covering primary production, ecosystem science principles, stoichiometry, and measurement methods as described in the provided lecture notes and transcript.

Primary production

The storage of energy through the formation of organic matter from inorganic carbon compounds.

Autotrophs

"Self-feeders" like plants and algae that produce the food needed for metabolism, growth, and reproduction.

Gross primary production (GPP)

The first step of primary production, which includes all carbon dioxide fixed into organic matter irrespective of respiratory losses.

Net primary production (NPP)

The difference between GPP and autotrophic respiration ($R_a$), representing the rate at which organic matter is available for uses beyond the producer's energy costs.

Ecosystem respiration ($R_e$)

The sum of autotrophic respiration ($R_a$) and heterotrophic respiration ($R_h$).

Net ecosystem production (NEP)

The difference between GPP and $R_e$, representing the total rate of organic carbon accumulation and export within an ecosystem.

Heterotrophic ecosystems

Ecosystems where total respiration exceeds gross primary production ($R_e > GPP$), often resulting from carbon imports or the use of stored organic matter.

Autotrophic ecosystems

Ecosystems with positive NEP, such as most forests and grasslands, that produce more carbon than they respire.

Chemosynthesis

The process of using chemical energy from oxidizing reduced inorganic compounds to fix $CO_2$ into organic matter.

Nitrifying bacteria

Chemosynthetic microbes that convert ammonia to nitrite or nitrite to nitrate to derive energy for fixing $CO_2$.

Methane-oxidizing bacteria

Microorganisms that exploit methane at the interface of aerobic and anaerobic environments to fuel growth via fixed $CO_2$.

14C method

A sensitive aquatic measurement technique that uses radio-labeled bicarbonate ($H^{14}CO_3$) to estimate rates between GPP and NPP.

Free water oxygen method

A measurement technique using underwater sensors to estimate GPP, $R_e$, and NEP based on daily oxygen fluctuations.

Allometric equations

Equations used in forestry to quantify the relationship between tree diameter and biomass.

Lidar

A remote sensing technology using pulsed laser light to provide detailed images of forest structure for biomass estimation.

ANPP

Above-ground net primary production; a common terrestrial measurement that excludes root production due to measurement difficulty.

Eddy covariance

A method measuring $CO_2$ concentrations in updrafts and downdrafts to calculate the net flux of $CO_2$ into and out of a canopy.

Net ecosystem exchange (NEE)

An instantaneous measurement of NEP expressed as the difference between $CO_2$ efflux and influx.

Pbmax

The maximum rate of photosynthesis achievable in a given light-production relationship model.

$\alpha$ (alpha)

The initial slope of the increase in a model of the relationship between net primary production and light.

Liebig's law of the minimum

The principle stating that ecosystem production is limited by a single factor, specifically the resource in shortest supply.

Stoichiometry

The study of the relative availability and ratios of elements like carbon, nitrogen, and phosphorus in ecological processes.

Macronutrients

Inorganic elements comprising greater than $0.1\%$ of an organism's wet weight, such as $N$, $P$, and $K$.

Micronutrients

Inorganic elements comprising less than $0.1\%$ of an organism's wet weight, often used as enzyme cofactors.

Seston

Particulate matter collected from water samples, consisting of a mixture of phytoplankton, detritus, and other organisms.

Pg C

Petagrams of carbon, a unit used for global budgets where $1\,Pg$ equals $1 \times 10^{15}\,g$.

Global marine NPP

A global estimate of net primary production in the oceans, calculated at approximately $52\,Pg\,C\,y^{-1}$.

Global terrestrial NPP

A global estimate of net primary production on land, calculated at approximately $54\,Pg\,C\,y^{-1}$.

Refractory organic matter

Organic matter that resists decomposition and can stay in soils or sediments for centuries to millennia.

DOC

Dissolved organic carbon; soluble organic matter that can be exported from terrestrial to aquatic systems.

Ecosystem

The interacting system consisting of all living and non-living objects in a specified volume.

Reductionism

A philosophical approach to understanding complex systems by studying their individual parts.

Holism

A philosophical approach to understanding complex systems by studying the intact system as a whole.

Black-box concept

The technique of measuring the inputs and outputs (functions) of a system without knowing all internal processes.

Mass balance

A tool that defines how ecosystems are connected by tracking material imports and exports to determine retention or loss.

Watershed

A land area that drains water, sediment, and dissolved materials into a common body of water like a lake.

Tracers

Labels, such as isotopes, added to systems to monitor the movement of atoms or molecules through an ecosystem.

Provisioning services

Ecosystem products that serve as physical, marketable goods, including food, fresh water, and timber.

Regulating services

Ecosystem benefits such as climate regulation, air quality control, and pollination.

Cultural services

Non-material ecosystem benefits including recreational, aesthetic, and spiritual opportunities.

Supporting services

Basic ecosystem functions like soil formation and nutrient cycling that support all other service categories.

Endolithic

Organisms that live within or penetrate deeply into stony substances like rocks or coral.

Hubbard Brook forest

A research site in New Hampshire known for long-term calcium budget studies using watershed mass balance.

Mycorrhizae

Fungal symbionts of tree roots that can constitute $10\%$ to $40\%$ of NPP in temperate forests.

Biogeochemistry

The study of how chemical elements and nutrients cycle through the biological, chemical, and physical components of an ecosystem.

Ecological energetics

A theme in ecosystem science focusing on the transfer of energy across an ecosystem.

Foliar C:N ratio

The mean molar ratio of carbon to nitrogen in terrestrial leaves, summarized as approximately $36$.

Foliar C:P ratio

The mean molar ratio of carbon to phosphorus in terrestrial leaves, summarized as approximately $970$.

Phytoplankton seston C:N

The mean molar ratio of carbon to nitrogen in marine seston, which is approximately $7.7$.

Phytoplankton seston C:P

The mean molar ratio of carbon to phosphorus in marine seston, which is approximately $143$.

Labile pools

Easily mobilized or exchangeable nutrient reservoirs in the soil.

Hypoxic

A condition in water bodies where dissolved oxygen concentration is $\le 2\,mg\,l^{-1}$.

Petagram (Pg)

A unit of mass equal to $10^{15}\,grams$.

HFIS

High-fidelity imaging spectroscopy; a tool used to estimate plant canopy characteristics and species richness.

Tundra NPP value

The net primary productivity for dry tundra, measured at approximately $65\,g\,C\,m^{-2}\,y^{-1}$ at Toolik Lake, Alaska.

Tropical evergreen forest NPP

A high-productivity site like Ducke Forest, Brazil, with an NPP of approximately $1050\,g\,C\,m^{-2}\,y^{-1}$.

Mirror Lake

An oligotrophic lake in New Hampshire used as a study site for aquatic primary production.

Photo-oxidation

The nonbiological oxidation of organic carbon caused by exposure to light, particularly ultraviolet light.

Episodic seeds

Masting events, such as those in oaks, that make seed production difficult to measure as part of NPP.

Anaerobic methane oxidation reaction

$5CH_4 + 8NO^{-}_3 + 8H^+ \rightarrow 5CO_2 + 4H_2 + 14H_2O$.