Question

How pesticides, herbicides, and fungicides are affecting the ecosystems? Explain bioaccumulation and biomagnification with examples.

Answer 1

Hint:Biomagnification and bioaccumulation is the increase or accumulation of substances at a particular trophic level in the food chain. These processes affect the organism in the food chain.

Complete solutionBiomagnification is also known as biological magnification. It is a process in which a particular toxic chemical or substance increases at a trophic level of the food chain. These substances arise from contaminated environments and the contaminants include heavy metals such as lead, arsenic, mercury, pesticides such as DDT, and polychlorinated biphenyls (PCB). These chemicals are consumed by organisms because of the food they consume. When an organism of a lower trophic level consumes some toxic substances and the organism at a higher trophic level consumes them then, the toxic substance starts building in the cells. With each trophic level the concentration of toxic substances increases. The organisms at higher trophic levels accumulate the highest amount of toxic substances. The most common example of biomagnification is- when a small fish consumes phytoplankton tinted with mercury then, the organisms at higher trophic levels consume this fish and will start the accumulation of toxic substances.
Bioaccumulation is the process that results in the accumulation of pesticides in an organism. It occurs when an organism absorbs a substance at a faster rate than it catalyzes the substance through excretion. The most common example is the bioaccumulation of DDT in birds of prey that leads to the thinning of eggshells, causing them to break easily during the process of incubation.

Note: Bioaccumulation is the process of accumulating a particular substance in the organism’s body while biomagnification is the process by which toxins pass from one trophic level to another trophic level in a food chain.