Abstract
The paper reviews past and present literature on microbial diversity, bio-geochemistry and how they are interrelated. The paper provides a short overview on diversity and the aquatic ecosystem and reviews some of the new techniques in measuring microbial diversity as well as some of the disadvantages of these techniques. The paper discusses the biogeochemical processes and presents studies that link diversity to the overall functioning of the system.

Outline:
Introduction
Biodiversity
Aquatic Ecosystem
Measurement of Microbial Diversity
Trophic Interactions in Aquatic Systems
Biogeochemical Cycling
Diversity and Aquatic System Functioning

From the Paper
"Although microorganisms are barely visible in the aquatic system, they play a very important role in the processes occurring in the system be it in the food web or in nutrient cycling of the system, also called biogeochemical cycle. According to Kiorboe (1993), the majority of the biological activity in pelagic systems are performed by microorganisms smaller than 100 m. Larger organisms, on the other hand, play a very minor role in the nutrient and energy cycling of the system."

Tags:ecosystems, microorganisms, biogeochemical, cycle

Abstract
This essay discusses the following issues: how the Neolithic period and Industrial Revolution impacted the natural environment and what is meant by environmental revolution; the biogeochemical cycles for carbon, nitrogen, and phosphorous and the human impact on these cycles; and the overall value of the natural ecosystems for human survival and the significance of measuring this value.

From the Paper
"The human society before the Neolithic Revolution (also called Agricultural Revolution) about 10~12,000 years ago, consisted of small groups of hunters/ gatherers who adapted to their environment and relied on the resources available in their surroundings. Their mobile way of life was suited to the raising of small families, which kept the populations in check and did not put a strain on the earth's environment. After the Neolithic Revolution, human beings started to live permanently in one place for the first time in their history. The dependence of the communities on small pieces of land for growing food put pressure on the environment. The human population began to expand exponentially since it was now desirable to have more children with agriculture requiring more "hands" in the fields. This impacted the environment further."

Tags:industrial, revolution, biogeochemical, ecosystem, cycle

Abstract
The paper offers a brief overview on the causes of the greenhouse effect and reviews the natural cycle of carbon. The paper then looks at some research about the interaction between global warming and the ocean. The paper focuses on the destruction of the thermohaline flow, increasing El Nino frequencies and the melting of ocean ice sheets.

Outline:
Introduction
How Does Global Warming Work?
The Biogeochemical Cycle of Carbon and the Influence of People
The Thermohaline Circulation and North Atlantic Deep Water
Formation Increasing Frequencies of El Nino
Global Warming and Ocean Ice Sheets
Conclusion

From the Paper
"Global warming, better known as the greenhouse effect, has over the past decades become a major environmental concern (Krebs 1994). The long-term effects of global warming are neither easily predictable nor easily studied. Researchers, however, are rapidly gathering new data on global warming by using computer simulations to study the phenomenon and by studying natural small-scale communities or artificial ones in laboratory settings. A good portion research is devoted to how best to combat the problem of global warming. In order to derive a strategy to "correct" the phenomenon, researchers investigate the causes of global warming and the movement of carbon dioxide, the most well known of the greenhouse gases (Krebs 1994). It has become clear that the ocean is a major carbon sink in the natural biogeochemical cycling of carbon and much effort is devoted to studying the impact the ocean may have on the greenhouse phenomenon (Krebs 1994)."

Tags:greenhouse, effect, carbon, cycle, El, Nino, thermohaline, flow, ice, sheets

Abstract
In this paper, the output of a soil nutrient, phosphorus, is examined and it is demonstrated that transpiration plays a role in the phosphorus cycle as transpiration can lead to phosphate output from the soil by initiating soil water extraction by plants. Definitions of key phrases are included within the text of the paper.

From the Paper
"Importantly, phosphorus, as an element, is present in phosphate, a water soluble compound characterized by one phosphorus atom for every four oxygen atoms. The water-soluble characteristic of phosphate is very important from the perspective of plant nutrient intake because, when phosphate is dissolved in soil water, it can enter a plant that draws soil water through its roots. However, in order for a plant to draw in soil water that may be enriched with phosphate, usually transpiration must occur first. For this reason, an analysis of how transpiration leads to the intake of soil water by a plant is necessary in order to understand transpiration's role in instigating the output of phosphorus from soil."

Tags:atmosphere, biogeochemical, cycling