The Living World: Ecosystems
In aquatic ecosystems, what are the main producers that contribute to primary productivity?
Amphibians
Crustaceans
Fish
Algae
What do producers rely on to create organic material through the process of photosynthesis?
Atmospheric pressure
Carbon dioxide and water
Soil minerals
Nitrogen and phosphorus
What consequence might arise from introducing a non-native plant species with rapid growth rates into an area with numerous endemic species relying on specific pollinators?
Alternatively because foreign floral characteristics encourage new pollinator types diversification occurs resulting temporarily enhanced cross-pollination benefits before potentially destabilizing original relationships between endemic plants their unique insect partners altering both populations negatively thereafter unexpected competition scenarios develop.
The rapid-growing non-native plants could outcompete native flora for resources leading ultimately toward ecological imbalance where endemic species experience declines affecting trophic interactions within local food webs thereby reducing overall area biodiversity.
What process is directly responsible for converting solar energy into chemical energy within an ecosystem?
Decomposition
Cellular respiration
Chemosynthesis
Photosynthesis
In designing an experiment to assess the impact of pesticide runoff on primary productivity, what additional factor must be taken into account to understand its influence on higher trophic levels?
Bioaccumulation effects in apex predators over time.
Immediate mortality rates among primary consumers upon exposure.
The rate of photosynthesis in producer species only.
Nutrient availability for plants within the ecosystem being tested.
Fertilizer runoff from agriculture can lead to eutrophication in nearby bodies of water, resulting in _____ .
Lower temperatures reducing algal blooms
Decreased levels of oxygen leading potentially causing fish die-offs
An increase in water clarity improving aquatic life conditions
A reduction in nitrogen levels limiting aquatic plant growth
How might increased atmospheric carbon dioxide levels directly affect the rate of primary productivity in phytoplankton populations?
Increase, due to enhanced photosynthetic activity.
Decrease, due to higher rates of respiration in warmer waters.
No change, as carbon dioxide does not influence aquatic systems.
Decrease, due to reduced availability of sunlight.

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How do you calculate the Net Primary Productivity (NPP)?
Multiplying the GPP with the percentage of solar energy captured by photosynthesis.
Subtract the amount of energy lost to respiration from the GPP.
Adding the amount of energy respired to the GPP.
Dividing the GPP by the percentage of solar energy that supports the growth and reproduction of producers.
In a grassland ecosystem experiencing drought conditions, how might reduced precipitation most immediately affect the energy transfer within its ecological pyramid?
Less plant growth resulting in less energy available for herbivores
An increase in secondary consumers due to lower competition for water resources
More carnivore activity as animals migrate searching for water sources
Enhanced decomposition rates providing more nutrients for soil microbes
How might the implementation of large-scale monoculture agriculture systems most directly affect regional primary productivity?
It might have little to no impact on primary productivity as agricultural output is primarily determined by technological advancements.
It could decrease biodiversity, leading to a reduction in ecosystem resilience and potentially lower net primary productivity.
It may lead to heightened primary productivity by maximizing space utilization and concentrating resources on select crops.
It could increase the regional carbon sink capacity due to uniform plant growth and higher photosynthetic efficiency.