Biomas in trophic levels!(:

 Biomass is the amount of energy stored in an organism that is passed on to the next trophic level. It is important to measure it because it determines the conditions of an ecosystem: if it is healthy or not. There are different ways to measure biomass:

1. Counting all the organisms of a species in a certain ecosystem. 

This method requires the researcher to count all the individuals and multiplying that number by the weight of one of them. Then, you would express biomass in terms of kilograms or grams divided by the area (which would be the area of the ecosystem or the part of it you are studying). This is the method that will probably give you the most correct estimate. However, it is difficult to carry out since it is almost impossible to count all organisms of a specie, especially if the area being studied is too big.

2. Doing a transect

To do a transect means to establish a certain length that will be studied, and then the individuals that fall under that area are the ones that will be counted. The researcher chooses the space, and after counting and obtaining the data, the results can be used to estimate it to the rest of the ecosystem. This method is widely used, but the estimates may be wrong or may not apply to the rest of the area under study. This is why sometimes researchers may do more than one, to get more data and compare the results.

3. Using quadrats

Quadrats are squares of a certain area that the researcher chooses. That square is placed in some areas of the ecosystem and the organisms that fall under that area are the ones considered in the estimate. It is likely that the researcher will do several quadrats because it is difficult to base the entire biomass of an ecosystem based on a small area. The areas chosen to do the quadrat may be random or have a reason behind their position.

4. Capturing/Marking/Releasing/Recapturing

Another method to measure biomass is one where the researcher captures a certain number of individuals, marks them, and then releases them back into the wild. Then, another bunch of individuals are captured, and the researcher analyzes how many of the ones caught in the second round were part of the ones in the first round (if they are marked). Then, there is a formula that states that the ratio of the marked individuals in the second round and the unmarked individuals is the same as the ratio of the individuals caught and marked in the first round and the total population. Based on that, the biomass of the ecosystem can be measured.

Biomass in the Savanna

One of the food chains in the savanna is: Shea fruit, eaten by the African elephant, eaten by the lion. Firstly, the number of individuals is needed:

(Units: individuals/squared km)

- 6438 Shea fruits

- 5 African elephants

- 15 Lions

Then, with the weight of each organism, we can then determine biomass:

(Units: kg/squared km)

- 128,740 Shea fruits

- 21,545 African elephants

- 2340 Lions