Science 6..11-12 Assignment Example | Topics and Well Written Essays - 750 words

Science 6..11-12 - Assignment Example Dead zones represent low-oxygen areas (hypoxic areas) in the world’s coastline and lakes. All organisms need oxygen to survive. The absence or low oxygen levels in these areas make it impossible for organisms to survive hence the term dead zone. The Gulf of Mexico gives a quintessential example of one such area. According to National Geographic, in 2010, the Gulf of Mexico Dead Zone was approximately 20,140 square kilometers. It has a seasonal hypoxic zone that forms every year in late summer. Its size varies from less than 5,000 square kilometers to approximately 22,000 square kilometers. The primary cause of dead zone formation is human activities. The upsurge in population has led to an increase in intensive agricultural and industrial activities. These activities lead to the emission of nitrogen and phosphorus into the environment i.e. soil, water and air. These are washed off into water basins such as oceans and lakes. These nutrients increase the fertility of the marine ecosystem; organisms like phytoplankton, algae and seaweed grow rapidly (algal bloom). This prevents the penetration of sunlight and absorption of oxygen by organisms living beneath the water surface leading to the reduction of the organisms immensely through death. Due to low-oxygen and available nutrients, the organisms (phytoplankton, algae and seaweed) eventually die and sink to the bottom of the sea where they are decomposed by bacteria. Oxygen can flow freely but is eventually used up by the process of decomposition leading to low-oxygen (hypoxia). Organisms that live beneath die or wither and others like the fish flee and a dead zone is formed. Several methods can be embraced to reduce the occurrence of dead zones. The use of synthetic fertilizers can be discontinued or reduced as they contain large quantities of nitrogen and phosphorus. Farmers can also use natural sources like compost and manure and adopt farming methods like contour cropping and no-till to reduce

Critical Thinking envi 423 Essay Example | Topics and Well Written Essays - 1250 words

Critical Thinking envi 423 - Essay Example The US economy and particularly the value of dollar is very much dependent on the oil of the Middle East and this is the reason; she gives priority to Saudi Arabia and Israel in her foreign policy. All the readings provided during this course were marvelous and has the greatest intellect value. Moreover, the course contributed to enhance my world view and helped me to develop the analytical skill to understand the events in details. However, the following three issues contributed significantly to my learning in this course: The present age is called the ‘era of information’. Media that includes television channels, radio, newspapers, magazines, journals and World Wide Web is busy in generating knowledge for viewers, audiences and readers. The media has its own shortcomings and hence it moulds the information as it suits itself or its country. Every piece of reading or broadcast has some sort of information but this cannot be declared authentic or we can call it ‘disinformation’. Resultantly, the world view based on this ‘disinformation’ would definitely lead astray. Junline Assange coined the term ‘scientific journalism’ to deal with this menace but still this is a utopia. prolific speeches by professional orators, logical argumentations and misuse of even true information have become the hall mark of the present day media. Moreover, entertainment industry has become the largest industry of the world and even education is also being imparted through t he modern techniques of entertainment which led to the creation of new term of ‘infotainment’. All this entertainment stuff and dazzling media satisfies the sensory needs of human being and does not invoke contemplation. This fuss will end up with the emergence of psychological problems, and ideological width among human beings. There is a dire need to rein the media as it is taking undue benefit of its liberty under the tag of media freedom. Another issue that contributed