DEAD ZONES

 UPSC GS MAINS IMPORTANT QUESTIONS

What are the consequences of spreading of 'Dead Zones' on marine ecosystem?




Dead Zones are hypoxic(low-oxygen) areas in the world's oceans  and larger lakes. Aquatic and marine dead zones can be caused by the process of Eutrophication, triggered by an excess of plant nutrients ( nitrogen and phosphorous) from fertilizers, sewage, combustion emissions from vehicles and factories.





The nutrients trigger a bloom of phytoplankton at the bottom of the marine food chain, allowing zooplankton to proliferate. As phytoplankton and zooplankton die and sink below the photic zone where photosynthesis can occur, a bloom of natural bacterial degradation exhausts water's dissolved oxygen. 





Dead Zones have spread exponentially since the 1960's and have serious consequences for marine ecosystem functioning. Low oxygen levels recorded along the Gulf Coast of North America have led to reproductive problems in fish involving decreased size of reproductive organs, low egg counts and lack of spawning.





The algae overgrowth blocks the sunlight which hampers the photosynthesis. Lack of sunlight can also lead to death of species in the littoral zones. Dead zones have now been reported from more than 400 systems, affecting a significant proportion of marine ecosystem and probably a key stressor on marine ecosystem.



Hello guys !!

This is Navina here. Visit my blog to get crisp contents on various stuffs!!

Comments

Post a Comment

Popular posts from this blog

DIGITAL SIGNATURE

Image
UPSC GS MAIN IMPORTANT QUESTION  DIGITAL SIGNATURE  Digital Signature a type of electronic signature which ensures the authenticity of the documents. It gives the information about the documents. It gives the information about the document creator and ensures that document is not altered or tampered. Authentication of digital signature means that the sender only knows the unique key along which any electronic record is tied. Hence, the sender cannot deny sending a message that he had sent. Digital Signature use encryption for ensuring the authentication of electronic document, which is done by password, checksum, CRC, private key encryption or public key encryption. Salient features of digital Signature: 1. Authentication of the Sender :                           It gives information about the creator of the document and thus authenticates the sender. 2. Data Integrity :                          It ensures that the content of the electronic document is not tampered. 3. Time Stamp :  
Read more

CHOLA ARCHITECTURE

Image
 IMPORTANT UPSC QUESTION : GS MAINS CHOLA  ARCHITECTURE  REPRESENTS A HIGH WATERMARK IN THE EVLOLUTION OF TEMPLE ARCHITECTURE. ENUMERATE. The Dravidian Architecture started by the Pallavas reached its high water mark and got matured at the hands of the Cholas. The Cholas refined Pallava architecture with the following notable features.                                                                                                                            ⁃ Cholas used stones instead of bricks. ⁃ They decorated the walls with sculptures and paintings od deities, kings and queen instead of lion motifs from Pallava. ⁃Temples were enclosed by decorative walls and entrance( Gopuram ). ⁃Temples built by the Cholas also had a great audience hall called Mandapa ; a deity room called Garbhgriha and pyramid like storey room called the Vimana . ⁃The temples were decorated by a beautiful Shikhara stone at the top.Each Shikara stone weighed in tonnes and had meticulous carvings on it. During th
Read more

PROTEST IN SHAHBAG SQUARE

Image
 UPSC GS MAINS IMPORTANT QUESTIONS The protest in Shahbag Square in Dhaka in Bangladesh reveal a fundamental split in society between the nationalists and Islamic forces. What is the significance for India? The Shahbag movement and the corresponding developments tell the story of two Bangladesh that co-exist. Bangladesh, the nation with two distinct mosaics: One a society comprising a vast majority of vibrant,egalatarian and secular individuals. It is the re-awakening of the social phenomenon or Renaissance if the liberation spirit has risen and protests against this from the other side of the divided political pysche has come up to assert because for them it is an existential question. The war crimes of 1971 did not only impact the victims of the crimes themselves,but the whole country.The Gono Jagoron Moncho would become political platforms to represent these grievances. Gono Jagoron Moncho came to present political calls for banning all religious political parties including Jamaat-e
Read more