Nutrient cycle Flashcards
How does water the potential gradient influence the rate of water flowing through plants?
The water potential gradient influences the rate of water flow by allowing water to move through the soil by unsaturated flow. Water moves from the soil (high water potential) to the roots where it moves plants and then to the atmosphere through the stomata. Water will continue to flow until a minimal water potential is reached.
How does
plant height influence the rate of water flowing through plants?
The Plant height influences the rate of water flow because the taller the plant the more the water has to travel from the roots to the leaves. Tall plants have taller xylem vessels to help water transport.
How does water the vessel diameter influence the rate of water flowing through plants?
Vessel Diameter influences the rate of water flow through plants by making it possible for taller plants to have water flow from the soil all the way to the leaves faster. larger diameter vessels can make it so water flows more quickly compared to smaller vessels.
How and why does deforestation influence the amount of runoff in streams?
Deforestation leads to increased surface runoff, which can affect the flow and quality of the water in streams. It can also lead to erosion,floods and sedimentation.
Which major flux couples Earth’s water cycle and energy balance?
The major flux is evapotranspiration, it accounts for 80% of heat transfer from the earth’s surface to the atmosphere.
What major factor controls photosynthetic rate and internal leaf CO2?
light intensity, temperature, water availability and nutrient availability.
What is the relationship between maximum photosynthetic rate and leaf longevity (positive or negative)? Why?
The higher the maximum photosynthesis rate is the higher the light compensation point is going to be. For example species living in low light conditions have low photosynthetic rate and low light compensation points.
What are the major factors that determine variation in plant respiration?
The major factors that determine variation in plant respiration are growth respiration, maintenance respiration and the respiratory cost of ion gradients.
Describe four strategies plants use to reduce growth limitation by any single resource, what are these four strategies, and describe how they work?
Terrestrial Plant allocation: this is when plants choose how to distribute growth. Plants allocate more above ground if light is limiting, or they allocate more to roots if soil nutrients or water is limiting, typically it’s better for plants to allocate equally between aboveground plants and roots.
Mutualism: this is the process of allocating plant C to obtain limiting resources. For example mycorrhizae which are fungal mutualists that increase soil volume used by plants, its a type of “Balanced parasitism”
Senescence: Its when plants shed leaves to reabsorb and translocate nutrients, explore new territories and get rid of parasites, pathogens ect.
Storage buffers: it’s when plants adapt to building a specialized structure to store and regulate water availability.
