Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
Human Impact on the Phosphorus Cycle
Like other biogeochemical cycles, human activities have altered the phosphorus cycle. Human beings mine phosphate rocks and guano deposits to make phosphorus available for production of fertilisers, detergents, animal feed, medicines, pesticide: and numerous other products. This mining exposes phosphate deposits made over millions of years. Phosphates are removed from soil through cropping of vegetation and to replace it phosphate fertilisers have to be added. Because of the abundance of calcium, iron and aluminium in the soil much of the phosphates get immobilised as insoluble salts. Thus more fertilisers have to be added. This results in high concentration of phosphates in agricultural runoffs. Similarly concentration of phosphorus in detergents, wastes of food processing plants, animal feed lot, sewage, etc., add to a considerable quantity of phosphorus poured in natural waters.
This problem becomes acute in urban areas. As said earlier, in aquatic ecosystems the phosphorus is taken up rapidly by the vegetation resulting in a sudden explosive growth of algae. Like nitrogen, this leads to cultural eutrophication of the water body. The producers cloud the water and forms a scum on the surface, blocking sunlight for the submerged plants. This is one example of the result of accumulation of nutrients at one stage of the nutrient cycle. It is important to note that the means of returning phosphorus to the cycle are inadequate to compensate for the loss. Sea birds have traditionally played-an important part in returning phosphorus to the cycle via their droppings (for example guano deposits off the coast of Peru) but apparently not at the rate at which it has occurred in the past. Unfortunately human activities appear to hasten the rate at which phosphorus is lost and thus make the cycle 'less perfect'. You could think our present use of phosphorus which is washed out into the rivers and finally into the oceans as an accelerated 'pouring' of phosphorus from the source to the sink.
State the Effects of alcohol and smoking for diabetics patient A major concern with alcohol consumption is the potential danger of hypoglycaemia (low blood sugar), especially w
what are the function of nucleus
Craninal nerves: Cranial nerves take their origin from different areas of brain Some of them are sensory, some are motor and a few are mixed nerves. There are 12 pair
Gene or point mutations occur when the DNA sequence of a gene is altered and the new nucleotide sequence is passed on to the offspring. This occurs either due to addition or deleti
Q. What are some representatives of the echinoderm phylum? Starfishes, sea urchins, sea cucumbers (holothurians) and brittle stars are examples of echinoderms.
A In taxonomy, what is a "KEY" ? List the different types of keys. How are they prepared and what are they used for ?sk question #Minimum 100 words accepted#
Haemocyanin - Respiratory Pigments This pigment is found in several arthropods and molluscs. Haemocyanins do not consist of haee groups. The metal they consist of is copper, w
why is virus an exception of cell theory
Write up your own Matlab program to do the job described by Show">http://www.avatar.se/molbioinfo2001/dynprog/adv_dynamic.html Show a few examples, your code does work. You wil
G round system: Plant tissue system, composed commonly of parenchyma cells with some collenchyma and sclerenchyma cells, that occupies the space between the epidermis and the va
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!
whatsapp: +91-977-207-8620
Phone: +91-977-207-8620
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd