In addition to solar radiation, the main abiotic factors that affect rates of photosynthesis and NPP are water, temperature, carbon dioxide concentration, and nutrients.
What 3 abiotic factors determine the productivity of an ecosystem?
The factors in an ecosystem that are considered abiotic, or nonliving, are very important to the primary productivity of the ecosystem. Those factors are both chemical and physical, and include light (radiation), temperature, water, atmospheric gases, and soil.
What causes NPP to vary in ecosystems?
Annual NPP changes from one year to the next in response to longer-term trends in climate, including shifts in total solar radiation caused by differences in cloud cover from year to year. Decadal patterns of NPP track changes in ecological succession (Gough et al.
What two ecosystems contribute the most to NPP?
In terms of NPP per unit area, the most productive systems are estuaries, swamps and marshes, tropical rain forests, and temperate rain forests (see Figure 4). Figure 4. Net Primary Production per unit area of the world’s common ecosystems.
How do ecosystems affect NPP?
Ecosystem water balance influences NPP through effects at several scales. … Respiration rates and the relative contributions of root, stem and leaf respiration vary with ecosystem water balance and therefore influence NPP.
What are the four factors important for NPP?
Four principal abiotic factors usually limit the amount of NPP on land – light, water, temperature, and mineral nutrients – and all these abiotic factors are changing rapidly as a result of human activity, with highly uncertain impli- cations for global and local NPP.
How does temperature affect NPP?
The effect of temperature change is generally positive to increase the productivity by enhancing the photosynthesis as long as the temperature is in a range of optimum level. When temperature exceeds the optimum level, it will increase the rate of respiration causing the NPP continuously declined.
How does NPP increase in terrestrial ecosystem?
In general, terrestrial ecosystem net primary production increases with increasing: moisture availability as measured by evapotranspiration. length of growing season. temperature measured as mean annual temperature.
Why does the NPP increase over time as the plants grow and mature )?
the NPP will increase over time because plants undergo metabolic process which increase the # of cells and cell products which can be used as energy for the next trophic level.
How does productivity increase in aquatic ecosystems?
On land, it is driven by temperature and availability of water and nutrients modified by land use. In aquatic ecosystems, primary productivity is driven by the availability of nutrients and light and, to a lesser extent, by temperature and other factors.
Which aquatic ecosystem has highest NPP?
Coral reefs show the highest gross primary productivity in the aquatic ecosystem. There are the wide number of phytoplankton and aquatic phototrophs which contribute to the productivity of the ecosystem.
What factors are most critical in affecting the net primary productivity of a terrestrial ecosystem?
Net primary productivity varies among ecosystems and depends on many factors. These include solar energy input, temperature and moisture levels, carbon dioxide levels, nutrient availability, and community interactions (e.g., grazing by herbivores) 2.
What biome has the highest NPP?
Tropical forests have the highest biodiversity and primary productivity of any of the terrestrial biomes. Net primary productivity ranges from 2–3 kg m–2 y–1 or higher.
How does drought affect NPP?
Lower temperatures at the beginning of the growing season could cause declines in NPP by shortening the length of the growing season. Mild drought or short-term drought with higher temperatures might increase NPP, and weak intensity droughts intensified the lag effects of droughts on NPP.
What limits NPP in terrestrial ecosystem?
Cold weather limits NPP by reducing the rate at which enzymes can catalyse reactions. When water is frozen, no biochemistry can occur. Even when the air temperatures rise sufficiently to allow photosynthesis, the soil nutrients may be locked up permanently in frozen soil (permafrost).
What factors influence the diversity of species that make up a forest?
The factors related to these patterns of small- scale species richness include (1) geographic factors such as scale of observation, available species pool and dispersal patterns, (2) biotic factors such as competition or predation and (3) abiotic environmental factors such as site resource availability, disturbance and …