Effects on aquatic organisms - water pollution, Biology

Assignment Help:

Effects on Aquatic Organisms - Water Pollution

Toxic water pollutants such as metals, pesticides, insecticides and chemicals affect aquatic species directly whereas the non-toxic organic load may eliminate some aquatic species indirectly by reducing the DO of water. The sensitive species such as Trout, and Bass that require high level of oxygen are eliminated first. With further decrease in DO, leeches, catfish and carp get killed and only the resistant species, for example, eel and hardy worms survive. Trout and salmon are excellent indicators of pollution. The aquatic flora of lakes and ponds is also affected by slight variations in sustaining elements, thus affecting the whole ecological system.

Generally plants and animals have the ability to wash out many poisons out of their system but certain chemicals such as pesticides, insecticides, methyl mercury tend to accumulate in the body. For example, DDT, an organochloride, does not dissolve in water but dissolves in fats, therefore, it accumulates in the organism for a long period. This is called bioaccumulation. These poisons then move in other organisms through food chain. For example, 0.02 ppm concentration of DDT in a lake entering into a bird through plankton (5 ppm), fish (400-300 ppm) may go up to 2000 ppm. Similarly, spray of DDT on soil (9.9 ppm) reaches 445 ppm in a Robin through plant (44 ppm). The increase in concentration of a toxin in food chain at higher level is called biomagnifications. Low levels of DO in water body expedite bioaccumulation because the rate of breathing of fish increases with decrease in DO. Hence it is forced to take in large amounts of water which may be polluted with toxic metals and chemicals. So their intake in fish would increase many fold than in the water body.


Related Discussions:- Effects on aquatic organisms - water pollution

Are bacteria the only prokaryotic beings, Q Are bacteria the only prokaryot...

Q Are bacteria the only prokaryotic beings? Prokaryotic beings are classified into two big groups: bacteria and archaebacteria (this last also known as eubacteria). Compared

Closed heart surgery, Closed Heart Surgery Blind operations and access...

Closed Heart Surgery Blind operations and access is obtained into the heart through incision on the ventricular or atrial wall. Commonest closed heart surgery done is m

Explain the term- loss-of-function mutation, Where would a predicted silent...

Where would a predicted silent mutation have to be situated to actually result in a loss-of-function mutation (and potentially lead to the onset of disease)? A. Intron-exon jun

Poultry and duck diseases-hydropericardium syndrome, Hydropericardium syndr...

Hydropericardium syndrome Hydropericardium syndrome (HPS), known as Leechi disease, is caused by Avian Adenovirus 4. HPS has been responsible for high mortality ranging from 6

What are the intermediate hosts of plasmodium, What are the intermediate an...

What are the intermediate and the definitive hosts of the plasmodium? In the life cycle of the plasmodium humans are the middle hosts (where asexual reproduction takes place) a

Explain in detail about working of heart, Explain in detail about working o...

Explain in detail about working of heart Heart has four chambers. Two upper chambers are called atria. Two muscular lower chambers are called ventricles. The right and left

Respiratory care on admission of patient, Respiratory Care on Admission (Fi...

Respiratory Care on Admission (First two hours) Patient is incubated and ventilator-dependent.  Monitor blood gases hourly and take corrective action immediately.

Tuberculosis - patients on haart, Patients on HAART Rifamycins induce h...

Patients on HAART Rifamycins induce hepatic CYP3A4 enzymes and can accelerate metabolism of protease inhibitors and some non-nucleoside reverse transcriptase inhibitors (NNRTIs

Water-soluble vitamins for school children and adolescents, Determine Water...

Determine Water-soluble vitamins needs of school children and adolescents? The suggested requirements are given in Table 15.2 (ICMR 1990). Thiamine is computed as 0.5 mg/1000 K

Basic structural pattern of limbs, Basic structural pattern of limbs ...

Basic structural pattern of limbs The common structural pattern of tetrapod limbs is extremely clear expressed in their skeletal components and in the manner they are organiz

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd