Diatom

Energy Flow and Nutrient Cycling in the Epipelagic Zone of the Ocean Introduction: “Energy Flow’’ is an environmental process that describes the flow of energy through a food chain and attempts to ascertain the relative importance of various individual component species and feeding relationships within a particular ecosystem. “Energy” itself is defined as the ability to do work: All living plants and animals expend energy in their environment. All three laws of thermodynamics apply,…

In bioturbation literature, it is often assumed that microbially-mediated processes have been affected by bioturbation, with no analysis of the microbial community (Kristensen, 1984, Kristensen, 1985, Kristensen and Blackburn, 1987, Gilbert et al., 1998, Christensen et al., 2000, Michaud et al., 2006, Bonaglia et al., 2014). For example, variations in microbial nutrient remineralisation (Renz and Forster, 2013), and declines in sediment functioning under reduced pH conditions (Widdicombe and…

Geo-engineering is defined as the artificial modification of the Earth’s climate system. The carbon dioxide in the atmosphere is increasing day-by-day, majority due to human activity. This is having negative effects on the climate and human beings. Researchers have created filtering machines to help reduce carbon dioxide concentration in the atmosphere. Also, researchers are thinking of artificially enhancing the growth of phytoplankton; which absorb nearly the same rate of carbon dioxide from…

Eutrophication is a natural occurrence over the past centuries as bodies of water age and contains sediment (Carpenter 1981). However, due to human activities, the rate of eutrophication has increased and now plays a big role in fish kills. This happens when inordinate amount of fertilizers flow down the rivers and streams and into the sea, which in turn encourages algae and most, if not all, aquatic plants to overgrow. Fishes will then suffocate due to lack of oxygen and sunlight excessively…

Did one single disaster cause the K-T extinctions? Some scientists and people are committed to just one reason the K-T extinctions occurred but in this paper many possibilities will be explored with evidence to back up why they could have been a cause as well to the extinctions. Everyone will ultimately make his or her own decision/thoughts on what could have happened, and of course all hypotheses would be subject to analysis. Asteroid impact theory. The impact of a 10 km+ asteroid would blow a…

Fossil fuels are a critical component in the functioning of our society. These resources are staples in maintaining the energized life styles that people have become used to. Fossil fuels are sources of energy derived from animal and plant remains from more than 300 million years ago (U.S. Department of Energy 2013). These remains were then coated with combinations of clay and rock called sediment (Energy Quest 2012). Sedimentary rock effectively protected the hydrocarbons in fossil fuels…

4a. The Canadian Arctic: Geography, ecology, people and climate The Arctic is often defined using political, climatic, biological zoning and varies greatly amongst Arctic nations. Using geophysical definition as the land and sea, north of the Arctic Circle and which experiences polar day from April to September, and polar night from October to February. Overall, Arctic climate varies greatly by location with annual mean surface temperatures of 4C in Reykjavic Iceland, to -28 C at the crest of…

environment. (Fu,F., Mulholland..). The more carbon and nitrogen fixation increases with an increase in atmospheric CO2 the more iron that is used up, in particular by phytoplankton. Thus the bioavailability of iron may reduce due to OA. Models of diatoms for Atlantic surface water have displayed them taking up iron at a slower rate in response to OA but phytoplankton’s requirement of iron is unchanged with increasing CO2 levels. Therefore, it is likely that there will be an iron stress on…

GG310 OCEANOGRAPHY Evaluate the geological evidence for so-called ‘Snowball Earth’ glacial episodes in the Precambrian and the hypothesis that these episodes were critical in the evolution of complex life. Introduction The importance of this period is that multicellular evolution began to accelerate after the last glacial ended.refbookpage829.The term Snowball Earth refers to the hypothesis that in the distant past, specifically the Cryogenian period (850-630 million years ago), the earth’s…

hormone formed in the body when the skin is exposed to sunbeams, mainly ultraviolet B light (UVB) rays22. The compound vitamin D has been found in organisms that are more than 500 million years old, including phytoplankton (Emiliania huxleyi), and diatoms (Skeletonema menxelii), which can endogenously synthesize vitamin D (ergosterol, or vitamin D2).Vitamin D is a steroid hormone with pleiotropic…