The carbon cycle

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  • The oceans cover over 70% of our planet's surface. Their physical, chemical and biological properties form the basis of the essential controls that facilitate life on Earth. Current concerns such as global climate change, pollution of the world's oceans, declining fish stocks, and the recovery of inorganic and organic chemicals and pharmaceuticals from the oceans call for greater knowledge of this complex medium. This volume brings together a number of experts in marine science and technology to provide a wide-ranging examination of some issues of major environmental impact....

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  • The citric acid or tricarboxylic acid cycle is a central element of higher-plant carbon metabolism which provides, among other things, electrons for oxidative phosphorylation in the inner mitochondrial membrane, intermediates for aminoacid biosynthesis, and oxaloacetate for gluconeogenesis from succinate derived from fatty acids via the glyoxylate cycle in glyoxysomes. The tricarboxylic acid cycle is a typical mitochondrial pathway and is widespread among a-proteobacteria, the group of eubacteria as de®ned under rRNA systematics from which mitochondria arose. ...

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  • Forests play a major role in global carbon (C) cycle, and the carbon density (CD) could reflect its ecological function of C sequestration. Study on the CD of different forest types on a community scale is crucial to characterize in depth the capacity of forest C sequestration.

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  • Coal formation has been described as “an inefficiency in the carbon cycle,” (Barghoorn, 1952) when carbon from plants remains in terrestrial sediments and is not recycled to the atmosphere (Figure 1.1.1). Coal is, by definition, a readily combustible rock containing more than 50% by weight and 70% by volume of carbonaceous material (Schopf, 1966). Another definition describes coal as a combustible solid, usually stratified, which originated from the accumulation, burial, and compaction of partially decomposed vegetation in previous geologic ages (Hendricks, 1945)....

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  • The glyoxylate cycle plays an essential role for anaplerosis of oxaloacetate during growth of microorganisms on carbon sources such as acetate or fatty acids and has been shown to contribute to virulence of several patho-gens.

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  • This document should be of interest to a broad audience interested in reducing greenhouse gas (GHG) emissions to the atmosphere. It was developed for regulatory organizations, project developers, and national and state policymakers to increase awareness of existing and developing monitoring, verification, and accounting (MVA) techniques. Carbon dioxide (CO2) sinks are a natural part of the carbon cycle; however, natural terrestrial sinks are not sufficient to absorb all the CO2 emitted to the atmosphere each year.

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  • Atmospheric levels of CO2 have risen significantly from preindustrial levels of 280 parts per million (ppm) to present levels of 384 ppm (Tans, 2008). Evidence suggests the observed rise in atmospheric CO2 levels is the result of expanded use of fossil fuels for energy. Predictions of increased global energy use during this century indicate a continued increase in carbon emissions (EIA, 2007) and rising concentrations of CO2 in the atmosphere unless major changes are made in the way energy is produced and used; in particular, how carbon is managed (Socolow et al.

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  • The prokaryotic ATP-citrate lyase is considered to be a key enzyme of the carbon dioxide-fixing reductive tricarboxylic acid (RTCA) cycle. Kinetic examination of the ATP-citrate lyase from the green sulfur bacterium Chlorobium limicola (Cl-ACL), an a4b4 heteromeric enzyme, revealed that the enzyme displayed typical Michaelis-Menten kinetics toward ATP with an apparent Km value of 0.21 ± 0.04 mM. However, strong negative cooperativity was observed with respect to citrate binding, with a Hill coefficient (nH) of 0.45. ...

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  • This chapter presents the following content: Photosynthesis converts light energy to the chemical energy of food, the light reactions converts solar energy to the chemical energy of ATP and NADPH, the Calvin cycle uses the chemical energy of ATP and NADPH to reduce CO2 to sugar, alternative mechanisms of carbon fixation have evolved in hot, arid climates.

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  • Against this background, we make several advances over the literature. We construct a new dataset that covers virtually the entire global stock market in capitalization terms and find—for this more comprehensive dataset—that industry effects have gone from less than half as important as country effects in the mid-1990s to almost twice as important in recent years. This shift is primarily driven by a dramatic rise in magnitude of industry effects, with country effects roughly stable since the mid-1990s.

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  • The world faces serious difficulties in obtaining the energy that will be needed in coming decades for a growing population, especially given the problem of climate change caused by fossil fuel use. This book presents a view of nuclear energy as an important carbon-free energy option. It discusses the nuclear fuel cycle, the types of reactors used today and proposed for the future, nuclear waste disposal, reactor accidents and reactor safety, nuclear weapon proliferation, and the cost of electric power.

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  • The soil ecosystem provides services such as carbon sequestration, nutrient cycling, water purification, provisioning of industrial and pharmaceutical goods, and a mitigating sink for chemical and biological agents. However, the soil is subject to various degradation processes. Its relation with the hydrosphere, biosphere, and atmosphere makes the interacting processes even more complex. Moreover, as the soilhuman interactions increase, threats, leading to a series of impacts on soil health, become more important....

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  • This textbook covers Plant Ecology from the molecular to the global level.

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  • These research teams study for example the impact and mechanisms of greenhouse gas emissions and atmospheric pollutant on climate, ozone depletion and carbon sinks (oceans and inland waters, forests and soil). They do research to understand the mechanisms and assess the impact of global change on the water cycle, water quality and availability, as well as soil functions and quality to provide the bases for management tools for sustainable water systems. Biodiversity and ecosystems are analysed to understand and minimise the negative impacts of human activities.

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  • Life on Earth is dependent on sunlight. In the process known as photosynthesis, plants, algae and certain bacterias are capable of using this source of energy to drive the synthesis of organic compounds. The oxygenic photosynthesis results in the release of molecular oxygen and the removal of carbon dioxide from the atmosphere that is used to synthesize carbohydrates.

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  • Oceanography is a very complex science. Its field study, the knowledge of the oceans and the seas and their physical and biological characteristics, is fundamental to comprehend many oceanographic and ecological aspects that directly influence the human life and the planet health. From micro-scale, like coastal processes, to macro-scale, like Global Change, the oceans, the seas and the marine life, play the main role to maintain the earth equilibrium, both from a physical and a chemical point of view (e.g. carbon cycle and water masses dynamic)....

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  • IN CHAPTER 5 WE DISCUSSED plants’ requirements for mineral nutrients and light in order to grow and complete their life cycle. Because living organisms interact with one another and their environment, mineral nutrients cycle through the biosphere. These cycles involve complex interactions, and each cycle is critical in its own right. Because the amount of matter in the biosphere remains constant, energy must be supplied to keep the cycles operational. Otherwise increasing entropy dictates that the flow of matter would ultimately stop.

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  • The environmental goods and services  (EGS) sector has  traditionally  included solutions  for problems  such  as  air, noise  and marine pollution,  land  and water  contamination,  as well  as  activities  such  as  environmental  analysis  and  consultancy  and  waste  management  and  recycling.  However  more  recently,  the  definition  of  this  sector  has  widened.

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  • Carbon  sectors  is  forecast  to  exceed  growth  in  the more  established  Environmental  sector, where  many technologies (for example in Water and Waste Treatment) are already mature.   The Renewable Energy and Emerging Low Carbon sectors currently show a much flatter growth than  previously  forecast  for  the  period  2012  to  2015.  It  is  anticipated  that  as  economic  uncertainty  is  reduced and investment funds start to flow, these growth forecasts will rise once again.

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  • Soil is a biogeochemically dynamic natural resource that supports all critical components that comprise terrestrial ecosystems. It has been called Earth’s living skin. On its June 11, 2004, cover, Science declared soils to be “the final frontier.” The growing awareness that soil provides a variety of ecosystem services beyond food production has attracted interest in soil from nonsoil scientists.

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