Earth carrying capacity

Remarkably, more recent estimates of the Earths carrying capacity center around a value of about 10 billion, not meaningfully different from the three-century old estimate of Leeuwenhoek. However, the range of estimates is very great - from under 2 billion to well over 20 billion If one performed today a calculation analogous to that of Leeuwenhoek, based on present national population densities, the world population extrapolates to about 3.6 billion with the United States as the reference base and 31 billion with the United Kingdom as the reference.13... 

If one of the structures to be bonded is the sheath or metallic armouring of an electric supply cable, special precautions will be necessary to ensure that the voltage rise at the bond in the event of an instantaneous earth fault on the power-supply system does not endanger personnel or equipment associated with other buried structures. The bond and any associated current-limiting device should be suitably insulated and of adequate current-carrying capacity. 

The broad problem of resource limitations in the face of a rising population is sometimes couched in terms of the "carrying capacity" of the Earth, or alternatively as the question that provides the title of the very comprehensive 1995 book by Joel Cohen, How Many People Can the Earth Support (Cohen, 1995). Defining what one means by carrying capacity involves both practical considerations and one s sense of values. Thus as Cohen writes ... 

Cohen reviews a large number of attempts to estimate the world s ultimate carrying capacity, dating back to the Dutch naturalist Antoni van Leeuwenhoek in 1679. As summarized by Cohen, Leeuwenhoek estimated the population density of Holland to be 120 per km2, assumed that land encompassed one-third of the Earth s total area, and extrapolated to a world population of about 13 billion. 12... 

Eco-efficiency Delivery of competitively priced goods and services that satisfy human needs and bring quality of life, while progressively reducing ecological impacts and resource intensity throughout the life cycle, to a level at least in line with the earth s estimated carrying capacity. The World Business Council for Sustainable Development developed the concept of eco-efficiency to look at cost optimization in the context of positive environmental benefits. 

On the other hand, there is the over-increase of world population and its related problems it has been claimed that humans have already exceeded the planet s ability to sustain their level of consumption, known as Earth s carrying capacity , by about 20%. That figure is expected to climb as more than 2 billion people living in India, China and other developing countries raise their standards of living in the near future, which will certainly cause ever-increasing pollution and toxic effects, unless more careful measures are planned and put in action. 

The ultimate question becomes. What is the carrying capacity of Earth— that is, what is the maximum population our planet can support Here is... 

What factors affect Earth s carrying capacity ... 

Earth s carrying capacity depends on the amount of productive land, agricultural practices, biotechnology advances, the rate of degradation of farmland, global pollution, the amount of water for irrigation, and the level of an acceptable quality of life. 

Carrying capacity is the theoretical Umit of population that the (Earth) system can sustain. 

Some authors consider the Earth s capacity to carry pollutants to be even more pressing a problem than those of depletion of material and energy sources. Like most industrial processes, the production and use of adhesives produces pollutants, which can have an adverse environmental effect. Much attention has been given in recent years to reducing their impact. 

By grounding a tool or electrical system, a low-resistance path to the earth is intentionally created. When properly done, this path offers suflSciently low resistance and has sufficient current-carrying capacity to prevent the buildup of voltages that may result in a personnel hazard. This does not guarantee that no one will receive a shock, be injured, or... 

Levine, R. S., Hughes, M. T, Mather, C. R. (2008). Sustainable city-regions Mega-projects in balance with the earth s carrying capacity. Paper presented at the Conference on Engineering Earth The Impacts of Megaengineering Projects. Lexington, Kentucky University of Kentucky. 23 July. 

Sustainable City Regions Mega-Projects in Balance with the Earth s Carrying Capacity... 

In tracing the evolutionary development of iron ligands it is of interest to examine the machinery employed by organisms which carry out reactions on those substances believed to have been present on the primitive Earth. Specific substrates acted on by this group include, besides ferrous iron itself, hydrogen sulfide, hydrogen gas, methane and reduced nitrogen compounds. Species which perform photosynthesis may be presumed to have the capacity to synthesize protoporphyrin IX since this substance is an intermediate in chlorophyll biosynthesis (43). 

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