Primary Production Flashcards
What percentage of the globe is covered by the terrestrial environment?
The terrestrial environment covers 29% of the globe.
What is the primary production in ecosystems?
Primary production is the uptake of CO2 by autotrophic organisms, like plants.
What factors are important for measuring gross primary production (GPP)?
Light, temperature, water, CO2, and O2 are important factors for measuring GPP.
What does NPP stand for in ecosystem productivity?
NPP stands for Net Primary Production.
What occurs during plant respiration?
Plant respiration (R) involves the loss of organic carbon as CO2 via aerobic respiration.
How is GPP typically measured in studies?
GPP is measured by observing changes in CO2 levels surrounding the atmosphere.
What is the equation relating GPP, R plant, and NPP?
The equation is NPP = GPP - R plant.
What is the role of Rubisco in photosynthesis?
Rubisco is responsible for attaching CO2 to ribulose in the dark reaction of photosynthesis.
How do C-4 plants differ from C-3 plants in CO2 fixation?
C-4 plants use PEP carboxylase for CO2 fixation, which has a higher affinity for CO2.
What is the primary benefit of C-4 photosynthesis?
C-4 photosynthesis allows for more efficient CO2 fixation with less water loss.
What does NEP stand for and what does it represent?
NEP stands for Net Ecosystem Production, representing potential organic matter accumulation.
How is light absorbed in vegetation?
Light is progressively absorbed as it passes through the vegetation layers.
What does LAI stand for in ecological studies?
LAI stands for Leaf Area Index, which measures the total one-sided area of leaf tissue per unit ground surface area.
What are the consequences of deciduous plants in different climates?
Deciduous plants lose leaves to conserve energy in short growing seasons, which can lead to organic matter loss in soils.
Which biomes are typically less productive in terms of biomass?
Grasslands and shrublands are usually less productive than forests in terms of biomass.
What is the effect of temperature and precipitation on biome productivity?
Temperature and precipitation predict the productivity of different biomes.
What are the main constraints on plant respiration?
Energetic costs due to growth, nutrient uptake, and maintenance respiration.
What is the relationship between GPP and NPP within biomes?
NPP scales proportionately with GPP within biomes.
How does photorespiration impact photosynthesis?
Photorespiration reduces photosynthesis by competing with CO2 for reaction sites on Rubisco.
What type of environments favor C-4 plants?
C-4 plants are favored in drier, warmer environments.
What is the role of stomata in plants regarding CO2 and water?
Stomata open to uptake CO2, which can lead to water loss through evaporation.
What are some major vegetation types in major terrestrial biomes?
Major vegetation types include tundra, taiga, temperate forests, grasslands, and deserts.
What happens to plant biomass during periods of high NEE?
NEE is negative if plant biomass increases or soil organic carbon increases.
What is an example of a biome affected by fire?
Grasslands and savanna ecosystems are often affected by fire.
How does seasonal rain affect vegetation types?
Different vegetation types adapt to seasonal rainfall, influencing their growth and productivity.
What does the acronym CAM stand for, and what purpose does it serve?
CAM stands for Crassulacean Acid Metabolism, which conserves water in desert plants.
How does temperature influence photosynthesis rates?
Photosynthesis rates typically show a unimodal response to temperature, being highest at optimal levels.
Why do herbaceous non-woody plants exist in environments with low water availability?
They have adaptations that minimize resource allocation to roots and manage desiccation.
What is the significance of plant biomass in carbon cycling?
Plant biomass represents a significant pool of organic carbon in terrestrial ecosystems.
How can ecosystem losses occur?
Ecosystem losses can occur through disturbances like burning, harvesting, and leaching.
What is the ecological importance of primary production?
Primary production contributes to the energy flow and nutrient cycling within ecosystems.
How does light quality affect plant growth?
Light quality influences the efficiency of photosynthesis and, consequently, plant productivity.
What does P/B ratio stand for, and why is it significant?
P/B ratio stands for Production/Biomass ratio, indicating productivity per unit of biomass.
What happens during the dark reaction of photosynthesis?
In the dark reaction, ATP and NADPH are used to convert CO2 into organic compounds.
What environmental factors influence the structure of vegetation in biomes?
Climate, soil type, and disturbance history influence the structure of vegetation in biomes.
How does the closure of stomata impact plant respiration and photosynthesis?
Closing stomata conserves water but can limit CO2 uptake, reducing photosynthesis rates.
What adaptations do plants have to tolerate high temperatures?
Some plants have mechanisms to cool themselves and prevent damage from excessive heat.
How does the presence of fire contribute to the dynamics of certain biomes?
Fire can shape ecosystem processes, influence species composition, and promote growth in certain biomes.
What is the impact of herbaceous C-4 plants during dry seasons?
They can continue to photosynthesize and survive despite limited water availability.
Why is it crucial to understand photosynthesis in the context of global patterns?
Understanding photosynthesis helps predict how ecosystems respond to climate change and manage resources effectively.
What is the effect of nitrogen uptake on plant growth relative to GPP?
Nitrogen uptake supports growth and is correlated with GPP, as plants require nutrients to thrive.
