Marine life Marine resources like oceans, rivers and lakes are the life support system for our planet, providing 97 percent of the Earth’s livable habitat and a home to more than , marine species. They are vital to human health as well, providing jobs, enjoyment and food to billions of people This sample of an academic paper on Week 4 Assignment reveals arguments and important aspects of this topic. Read this essay’s introduction, body paragraphs and the conclusion below. Organism Physiology: The Octopus Bio/ The cephalopodor octopus is a marine organism that inhabits many diverse regions of the ocean 1/2/ · Plastic is having a significant effect on the marine environment. It is causing big problems in the ecosystem, but the most dangerous plastics are microplastics. These plastics are decreasing the population of all marine life
The Effect Of Plastic On Marine Life: Free Essay Example, words
Written by the educators who created The Deep Ocean, a brief look at the key facts, tough questions and big ideas in their field. Begin this TED Study with a fascinating read that gives context and clarity to the material.
In the late s, the Apollo Mission captured images of Earth from space for the very first time. These iconic photos gave people around the world a fresh perspective on our home planet — essay on marine life specifically, its vast and dazzling expanses of blue. It's perhaps unsurprising that science has subsequently established the key roles that the ocean and its marine organisms play in maintaining a planetary environment suitable for life. While the Apollo astronauts were sending back pictures of our blue planet, a scientist at the Jet Propulsion Laboratory in California was searching for ways to detect life on other planets such as Mars.
James Lovelock's investigations led him to conclude that the only way to explain the atmospheric composition of Earth was that life was manipulating essay on marine life on a daily basis. In various publications, essay on marine life his seminal book Gaia: A New Look at Life on EarthLovelock launched the Gaia hypothesis, which describes how the physical and living components of the natural environment, including humankind, essay on marine life, interact to maintain conditions on Earth.
During the same period, essay on marine life, marine scientists including Lawrence Pomeroy, Farooq Azam and Hugh Ducklow were establishing a firm link between the major biogeochemical cycles in the oceans and marine food webs, particularly their microbial components. In the late s and s, large-scale research programs like the Joint Global Ocean Flux Study JGOFS explored ocean biogeochemistry and established the oceans' pivotal role in the Earth's carbon cycle.
Research efforts like these underscored the oceans' critical importance in regulating all the major nutrient cycles on Earth. It's now widely recognized that the ocean regulates the temperature of Earth, controls its weather, provides us with oxygen, food and building materials, and even recycles our waste.
It seems remarkable that until fairly recently many scientists believed that life was absent in essay on marine life deep sea. Dredging in the Aegean Sea in the s, marine biologist Edward Forbes found that the abundance of animals declined precipitously with depth. By extrapolation he concluded that the ocean would be azoic devoid of animal life below fathoms ~m depth. Despite evidence to the contrary, scientists supported the azoic hypothesis, reasoning that conditions were so hostile in the deep ocean that life simply could not survive.
Extreme pressure, the absence of light and the lack of food were viewed as forming an impenetrable barrier to the survival of deep-sea marine species. But others were already proving this hypothesis wrong. As Edward Forbes published his results from the Aegean, Captain James Clark Ross and the famous naturalist John Dalton Hooker were exploring the Antarctic in the Royal Navy vessels HMS Terror and HMS Erebus.
During this expedition, Ross and Hooker retrieved organisms from sounding leads at depths of up to 1. Ross remarked, "I have no doubt that from however great a depth we may be enabled to bring up the mud and stones of the bed of the ocean we shall find them teeming with animal life. Further evidence came from natural scientists William Carpenter and Charles Wyville-Thomson, who mounted expeditions in and on the vessels HMS Lightening and HMS Porcupine to sample the deep ocean off the British Isles, Spain and the Mediterranean.
The findings of these expeditions, essay on marine life, which Wyville-Thomson published in his book The Depths of the Seaconfirmed the existence of animal life essay on marine life depths of fathoms — including all the marine invertebrate groups — and suggested that oceanic circulation exists in the deep sea.
This convinced the Royal Society of London and the Royal Navy to organize the circumnavigating voyage of HMS Challenger in the s. In part, the expedition's purpose was to survey potential routes for submarine telegraph cables, essay on marine life, and so the links between scientific exploration and human use of the deep sea were established in the very early days of oceanography.
The Challenger expedition was a watershed for deep-ocean science, establishing the basic patterns of distribution of deep-sea animals, and that their main food source was the rain of organic material from surface waters, essay on marine life. In the s, the Danish Expedition Foundation's Galathea voyage established that life occurred at depths of more than 10km in the Philippines Trench.
In marine explorers Auguste Picard and Don Walsh reached the bottom of the Challenger Deep in the Marianas Trench, at a depth estimated to be 10, meters--the deepest part of the ocean — where they observed flatfish from the porthole of their pressure sphere.
This feat was not repeated until when James Cameron visited the bottom of the Challenger Deep in the submersible Deepsea Challenger. While working at Woods Hole Oceanographic Institution in the late s, scientists Howard Sanders and Robert Hessler developed new types of deep-sea trawls called epibenthic sleds that featured extra- fine mesh in the nets. When the new trawls were tested, they recovered an essay on marine life diversity of species from the deep sea.
It became apparent that the species richness of deep-sea communities actually increased with greater depth to a peak somewhere on the continental slope between 2, and 4, meters depth. Beyond these depths, diversity appeared to decrease but not everywhereessay on marine life, or the pattern was unclear.
How to explain this amazing diversity in the deep sea? Initially, scientists credited the species richness to the stability of environmental conditions in the deep ocean, which would support extreme specialization of the animals and thus allow many species to coexist. This is known as the stability-time hypothesis. Some scientists considered that small-scale variations of the sediments of the deep ocean, including reworking of seabed by animals, was important in maintaining microhabitats for many species.
In the late s other scientists suggested that conditions in shallow waters allow competitive exclusion, where relatively few species dominate the ecosystem, whereas in deeper waters environmental factors associated with depth and a reduced food supply promote biological communities with more diversity. Fred Grassle and Nancy Maciolek added substantially to our knowledge of deep-sea biodiversity when they published a study of the continental slope of the eastern coast of the USA in the early s.
Grassle and Maciolek based their study on quantitative samples of essay on marine life sediments taken with box cores. These contraptions retrieve a neat cube-shaped chunk of the seabed and bring it to the surface enclosed in a steel box. Scientists then sieve the mud and count and identify the tiny animals living in the sediment. In a heroic effort, Grassle and Maciolek analyzed box cores, essay on marine life, an equivalent of 21 square meters of the seabed, identifying 90, specimens and species.
They estimated that they found approximately species per km along the seabed they sampled. Extrapolations of this figure suggested that there may be 1 - 10 million macrofaunal species in the deep sea. What's more, some scientists argued that Essay on marine life and Maciolek's estimates represented only a small part of the species diversity in the ocean depths. Dr John Lambshead of London's Natural History Museum pointed out that Grassle and Maciolek had not examined the smallest animals in sediments — the meiofauna — made up of tiny nematode worms, copepods and other animals.
These are at least an order of magnitude more diverse than the macrofauna, suggesting that as many as million species may inhabit the deep ocean. However, given that the latest approximation of the Earth's biodiversity is 10 million species in total, Lambshead's number appears to be an overestimate.
Scientists have since realized that there are major problems with estimating the species richness of large areas of the deep sea based on local samples.
Today we understand that species diversity in the deep ocean is high, but we still don't know how many species live in the sediments of the continental slope and abyssal plains.
We also don't understand the patterns of their horizontal distribution or the reasons for the parabolic pattern of species diversity as it relates to depth. Evidence suggests, however, that the functioning of deep-sea ecosystems depends on a high diversity of animals — although exactly why remains open to conjecture. InGerman scientist Alfred Wegener put forward his theory of continental drift to address many questions that engaged the geologists and biologists of his time.
For example, why do the continents appear to fit together as though they had once been joined? Why are many of the large mountain ranges coastal? And, perhaps most intriguing, why do the rocks and fossil biotas combined plant and animal life on disconnected land masses appear to be so similar?
Wegener's theory provoked a major scientific controversy that raged for more than 50 years between "drifters" and "fixists. In the search for an alternate mechanism to explain continental drift, British geologist Arthur Holmes suggested that radioactive elements in the Earth were generating heat and causing convection currents that made the Earth's mantle fluid.
Holmes essay on marine life that the mantle would then rise up under the continents and split them apart, generating ocean basins and carrying the landmasses along on the horizontally-moving currents. Following World War II, scientific expeditions employing deep-sea cameras, continuously recording echo-sounders, deep-seismic profilers and magnetometers lent support to the arguments of Holmes and his fellow "drifters.
These ridges were characterized by fresh pillow lavas, sparse sediment cover, intense seismic activity and anomalously high heat flow. Scientists found geologically-synchronous magnetic reversals in the rocks of the ocean crust moving away from either side of the mid-ocean ridges. Added to this was the fact that nowhere could essay on marine life find sediments older than the Cretaceous in age.
Together, these findings suggested that new oceanic crust was being formed along the mid-ocean ridges, while old oceanic plates are forced underneath continental plates and destroyed along the ocean trenches. By the late essay on marine life, the bitter scientific debate between the "fixists" and the "drifters" was finally settled.
During the next decade, scientists investigating volcanic activity at mid-ocean ridges became interested in the associated phenomenon of hot springs in the deep sea. Anomalously high temperature readings over mid-ocean ridge axes led scientists to mount an expedition in to the 2.
From the submersible Alvin, the scientists observed plumes of warm water rising from within the pillow lavas on the seabed. Living amongst the pillows were dense communities of large vesicoyid clams, mussels, limpets and giant vestimentiferan tube worms Siboglinidae. An abundance of bacteria around the Galápagos Rift site immediately suggested that these communities might be based on bacterial chemosynthesis, or chemolithotrophy, using chemical energy obtained by oxidizing hydrogen sulphide to drive carbon fixation.
Subsequent investigation confirmed that the giant tube worms, clams and mussels actually hosted symbiotic sulphur-oxidizing bacteria in their tissues. The discovery caused huge excitement in the scientific community. Here was life thriving in the deep sea, where primary production — the basis of the food web — was independent from the sun's energy. Furthermore, as scientists discovered additional vent communities and surveyed elsewhere in the mid-ocean ridge system, they found that environmental conditions were extreme, with high temperatures, acidic waters, hypoxia lack of oxygen and the presence of toxic chemicals the norm, essay on marine life.
The implications of this were enormous and went well beyond the study of the ocean itself. First, it meant that life could exist elsewhere in our solar system in environments previously thought too extreme. Second, it widened the potential area for habitable planets around suns elsewhere in the universe.
For example, the discovery in of the Lost City alkaline hydrothermal vents presented an environment that some scientists suggest is analogous to the conditions in which life evolved on Earth. Subsequently, chemosynthesis has been discovered in many places in the ocean, including deep-sea hydrocarbon seeps, in large falls of organic matter such as whale carcasses, and from shallow-water sediments associated with, for example, seagrass beds.
Over the past two decades, we've developed a much deeper understanding of the relationship between humankind and the natural world, essay on marine life, including the Earth's oceans. In Robert Costanza and his colleagues published a paper in Nature that estimated the economic value of the goods and services provided by global ecosystems. These goods and services were later grouped into supporting e. primary productionprovisioning e. foodregulating climate regulation and cultural e.
education services. While this knowledge may have been essay on marine life for many people, Costanza's recasting of the environment in economic terms forced policymakers, industry leaders and others to recognize the importance of long-term environmental sustainability. With the support of international agencies such as the World Bank, essay on marine life, many countries are now implementing natural capital accounting procedures through legislation.
The purpose of this is to help monitor and regulate the use and degradation essay on marine life the environment and to ensure that the critical ecosystem goods and services underpinning economic activity and human well-being are not undermined. Although it seems like a modern preoccupation, sustainability is actually a centuries-old challenge, particularly as it relates to marine environments.
For essay on marine life, there is evidence that aboriginal fisheries in ancient times may have overexploited marine species. Certainly by medieval times in Europe, a thriving market for fish, coupled with other developments like changing agricultural practices, forced species such as salmon and sturgeon into decline.
The Industrial Revolution led to an increase in hunting fish, seals and whales, thanks to the development of steam- and then oil-powered fishing vessels that employed increasingly sophisticated means of catching animals. Pelagic whaling began in the early 20th century; the development of explosive harpoons, the ability to process whales at sea, and the strong demand for margarine made from whale oil all contributed to dramatic rises in catches.
Despite the initiation of the International Whaling Commission ina serial depletion of whale populations took place from the largest, most valuable species e. blue whale through to the smallest species minke whale. The failure to regulate catches of whales led to the establishment of a near-moratorium on whaling in Over the same post-war period, fishing fleets underwent a major expansion and deployed increasingly powerful fishing vessels.
Improved technologies for navigating, finding fish and catching them led to increasing pressure on fish stocks and the marine ecosystems in which they lived.
15 Words - About Sea Life
, time: 5:24Essay On Marine Life Protection - Words | Internet Public Library
1/2/ · Plastic is having a significant effect on the marine environment. It is causing big problems in the ecosystem, but the most dangerous plastics are microplastics. These plastics are decreasing the population of all marine life Introductory essay Written by the educators who created The Deep Ocean, a brief look at the key facts, tough questions and big ideas in their field. Begin this TED Study with a fascinating read that gives context and clarity to the material. How inappropriate to call Marine life Marine resources like oceans, rivers and lakes are the life support system for our planet, providing 97 percent of the Earth’s livable habitat and a home to more than , marine species. They are vital to human health as well, providing jobs, enjoyment and food to billions of people
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