GPP Full Form
What is the full form of GPP?
The expanded form of GPP is gross primary productivity. It is defined as the total amount of carbon produced by the process of photosynthesis in plants in a particular period. All organisms in this world depend on gross primary productivity. Plants are also known as primary producers because they are responsible for primary production. It is expressed in units of energy (kcal/m2/yr) or weight (g/m2/yr). Where net primary productivity is defined as the amount of energy that passes to the primary consumer after utilizing energy for respiration. It can also be defined as the amount of biomass or energy available for primary consumers. To know more about gross primary productivity, continue reading this article.
Factors affecting GPP
Many factors affect gross primary productivity. Some of the factors are given below:
Temperature is one of the most important factors affecting gross primary productivity, as the activity of enzymes is greatly affected by temperature.
Moisture is also one of the factors that affect the productivity of plants.
Solar energy: the more solar energy there is, the faster photosynthesis occurs.
Nutrients: the availability of nutrients also affects gross primary productivity. Productivity will increase with the availability of nutrition.
How is gross primary productivity calculated?
There are two important methods used to measure the rate of productivity. These methods are explained below:
The C14 method is one of the most accurate ways to determine gross primary productivity. Radioactive carbon is used in this method, where carbonated water is added. A bottle is taken in which water, other phytoplankton, and other organisms are kept. Then a small amount of labeled radioactive carbon is added, and after some time, phytoplankton and other organisms are removed from this bottle. With the help of radioactive counts, the total amount of fixed radioactive carbon can be calculated.However, we can only calculate the amount of carbon fixed in tissues using this method; as a result, only net primary productivity has been calculated so far.
Oxygen production method: gross primary productivity can be calculated by estimating the amount of oxygen utilized by a particular volume of water in a given period. Here, water is kept in a dark, tight bottle. This method can only be used to determine gross primary productivity. Sometimes, after some phytoplankton and other living organisms grow into the water, all the oxygen produced by this phytoplankton is utilized in respiration; as a result, there is no evolution of oxygen.
Terrestrial production
On the land, primary production is done by plants, algae, and bryophytes. Water and sunlight play an important role in the primary production of plants. Sunlight also aids in temperature regulation. If the temperature were less or more than the normal temperature, the rate of photosynthesis would be less, and gross primary productivity would also be less. Only the availability of sunlight is not enough for photosynthesis; rather, the availability of photosynthetically active radiation is necessary for good primary productivity. We all know that more than 90% of the water absorbed by plants is lost through transpiration. But transpiration is very necessary for transporting water and other essential minerals.
Oceanic production
As we all know, more than 70% of our earth is covered with water, but the productivity of the ocean is very low compared to land. We saw in the previous paragraph that plants perform the majority of photosynthesis on land, whereas algae and phytoplanktons perform the majority of photosynthesis in oceans and other aquatic systems. Here, the availability of light and nutrients is essential for proper photosynthesis because water is available in enough amounts.
Frequently Asked Questions (FAQs)
net primary productivity is calculated by subtracting respiratory losses from gross primary productivity. Gross primary productivity minus respiratory productivity equals net primary productivity.
coral reef ecosystem has the highest gross primary productivity because it has the highest number of autotrophs.
No, net primary productivity cannot be greater than gross primary productivity.
Deserts have low primary productivity because of some unfavorable environmental conditions, like the absence of water and high temperatures.
Yes, net primary productivity increased with temperature, but only up to a certain point, after which an increased temperature would decrease productivity.