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Summary

Through succession and adaptation, numerous species of plants are created with certain environmental characteristics in order to cope with their surrounding ecological niche. In these respective conditions, plants flourish and grow profusely, slowly adapting in a co-evolutionistic bond with nature’s deviations. But what might happen if the plant were removed from its usual ecosystem and taken elsewhere, where different light, soil and climate conditions were present. As humans have developed to leave their previously nomadic lifestyle and reside in one location, they created sustainable food sources from which they could constantly rely on. The cultivation of crop continues to be a key part of human life. Additionally, humans hold emotional and sentimental value to the growth of plants and flowers in residential areas and gardens. To ensure that these important aspects of human life continue to feed and please the world, botanists try to create the ideal conditions for plant life such that they can provide the most nutritious, plentiful crops and most beautiful flora and much more. Here is a simple link describing the basics of plant growth:
http://www.gardeningfield.com/basics/growth-factors.html


Light

Light is an essential factor that allows for plant survival and growth; however, certain plants require different light conditions than others.(1) Some plants need large amounts of sunlight hours in order to supply the plant with enough energy for daily functions, while other plants, known as full shade plants, require longer periods of darkness to survive.
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Grow lamps try to simulate sunlight all year round in liveable conditions
(1) These plants cannot tolerate long periods of sunlight as this increase can lead to oxidative damage to crucial pigments in the plant, especially chlorophyll, reducing the efficiency of photosynthesis or even plant scalding to intense heat.(2) A typical plant’s growth however, is reliant on the three principles of light: intensity, quality and duration.(1) With most plants, the intensity of sunlight a plant receives is directly proportional to its capability to create glucose for energy, via photosynthesis to a certain cut-off point specific for each plant.(3) Additionally, different wavelengths of light contribute differently to the plant and thus act as the quality of the light; blue light is important for leaf growth while red light combined with blue is helpful for the growth of the flowering reproductive system.(3) And finally the number of daylight hours that a plant receives is attributed to the growth a plant undergoes.(1) If any of these quantitative and qualitative factors are lowered, the plant will show signs of deterioration since the plants would not be able to produce chlorophyll, and thus undergo the reaction to create an available energy source, stored in glucose molecules.(1) However, if the proper lighting conditions are available for the plant, it will flourish,(2) on the basis that all the other factors are properly balanced as well. A simple animation of photosynthesis is available at the following link:
http://www.kscience.co.uk/animations/photosynthesis.htm


Soil Composition

Soil is a dense substrate that both anchors the plant down and acts as a “highway” connecting the roots to the underground nutrients and living matter.(4) Soil is comprised of two main parts: the abiotic rock material and the biotic organic material.(4) The rocky matter underground is comprised mainly of stone, clay and silt.(4) Clay is composed of fine particles which are chemically-active, reminiscent fragments of stone.(4) Having too much clay can result in large amounts of clumping and may create too many large clusters of rock, silt and sand.(4) The organic matter in soil is created from once-living organisms which decompose via decomposers.(4)
Once it has been completely decomposed, in which very little valuable material is available for fungi and bacteria, only resins, waxes and gums remain.(4) Combined together, these by-products are known as humus and acts as an adhesive, sticking to other parts of the soil until the valuable plant nutrients, nitrogen, potassium and carbon are extracted from the soil from plants.(5) If little humus is present in the soil, plant growth will be increasingly difficult and compromised, as the plant will not have as many nutrients readily available.(5)

pH Level & Nutrients

In the soil of plants, the composition and balance of nutrients, water and other materials affects the pH from which the plant extracts the necessary substances to sustain life.(6) All plants have different tolerances and ideal soil pH and thus can survive in different ecosystems.(6) Soil can become acidic from the leaching of acidic nutrients through rain water, large amounts of carbon dioxide dissolving in soil water, and the formation of acids from fertilizer.(6) If soils are too acidic, certain nutrients such as aluminum and iron are too abundant and other nutrients are lacking presence in the soil.(6) On the other hand, lime is a mineral that creates an alkaline soil pH, which conversely has opposing nutrients in excess.(6) In order for an increased growth rate, the pH level in the soil must correspond to that ideal for the specific plant and must allow for all 17 essential nutrients to be present for plant absorption.(6)




Climate Change

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Deciduous trees lose their leaves in the winter to avoid the falling snow.

Many plants are able to survive in different climates, using abilities acquired through adaption to stay alive in harsh climates.(7)
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Cacti have the ability to store large amounts of water for long periods of time.
Deciduous trees lose their leaves every winter so all the snow falls off their branches and thus does not drop the trees' temperature as drastically.(7) Without these measures, the cold temperatures would more directly affect the trees and cause damage from sub-zero weather.(7) Contrarily, cacti have large, membranous cavities that can store water from minimal rainfall and use it sparsely until another rainfall occurs.(7) For an average plant however, extra cold temperatures can cause the plant to freeze and die, while unforeseen heat waves can cause the plant to lose large amounts of water and potentially shrivel up from a lack of moisture.(8) They may also burn and lose function of these burnt areas if intense heat is present.(8)


Article

The following article at http://green.blogs.nytimes.com/2010/08/23/plant-growth-affected-by-climate-change-study-finds/, describes a relevant issue in which the increase in carbon dioxide that would presumably have increased plant growth, seeing as it is a key component in plant photosynthesis, has actually showed signs of decreasing the amount of vegetation on the Earth.(9)
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Carbon dioxide emissions are affecting every part of the globe.
This article relates to the following wiki page, in that it describes a real life issue that is significantly showing signs of greater damage within subsequent generations.(9) Although northern, colder areas have now been experiencing longer growth periods and increased heat, the southern areas around the equator are encountering prolonged periods of drought, which is causing species that have survived for millions of years to suffer great loses.(9) From 1982 to 1999, a 6% increase in plant growth has been noticed through NASA satellite images, attributed to the extended growing seasons; yet in the last 9 years, the growth had dramatically hit a peak, decreasing by 1%.(9) Although this small fraction may appear to be inconsequential, this is only the first of a lengthy change that will greatly affect the world's ecosystems if human CO2 emissions are not significantly reduced.(9)

Glossary


Bibliography


  1. Bitman S. Lights' Effect on Growth - Biology Online [Internet]. Chicago (IL); [updated 2004 Jan 23; cited 2012 Jan 15]. Available from: http://www.biology-online.org/3/9_effect_light.htm.
  2. Yarnell A. C&EN: Latest News - When Plants Get Too Much Sun. Washington (DC) 2005 Jan 24 [cited 2012 Jan 15]. Available from: http://pubs.acs.org/cen/news/83/i04/8304notw6.html.
  3. VanDerZanden A. Plant growth and light, Botany Course, Master Gardener Training, Extension Service [Internet]. Corvallis (OR): University of Colorado [cited: 2012 Jan 15]. Available from: http://extension.oregonstate.edu/mg/botany/light.html
  4. Spencer B. Soils: Soil composition. [Internet] Mediateam Ltd [updated 2011 Jan 15] Available from: www.garden.ie/gardeningskills.aspx.
  5. Scharf R. Soil Composition and Formation. [Internet] ACE basin [cited: 2011 Jan 15] Available from: nerrs.noaa.gov/Doc/SiteProfile/ACEBasin/html/envicond/soil/slform.htm.
  6. Bicheklhaupt D. Soil pH: What it Means. [Internet] Syracuse (NY) SUNY-ESF[cited: 2012 Jan 15] Available from: http://www.esf.edu/pubprog/brochure/soilph/soilph.htm.
  7. Dulson J, Guiseppe M, Fraser D. Nelson Biology 11: University Preparation. Toronto (ON) 2011; 14(1).

8. Whiting D, Plant Growth Factors: Temperature. [Internet] Fort Colins (CO) [cited: 2012 Jan 16] Available from:
http://cmg.colostate.edu/gardennotes/143.pdf.

9. Rudolf J. Earth's Plant Growth Fell Because of Climate Change, Study Finds. [Internet] New York (NY) [cited: 2012 Jan 16] available from:
http://green.blogs.nytimes.com/2010/08/23/plant-growth-affected-by-climate-change-study-finds/.


Pictures and videos:

Picture - Grow lamps:
http://www.google.ca/imgres?q=plant+lights&um=1&hl=en&sa=N&tbm=isch&tbnid=V5edaLh0Zv0VdM:&imgrefurl=http://img86.imageshack.us/i/growingarea005vz3.jpg/%3Fa%3Dj%26ci%3D-1%26rt%3D&docid=L1c6-4BMBCmQyM&imgurl=http://img86.imageshack.us/img86/2900/growingarea005vz3.jpg&w=800&h=600&ei=mI4TT-6NFMapgwe8pJnGAw&zoom=1&iact=hc&vpx=627&vpy=154&dur=55&hovh=194&hovw=259&tx=132&ty=98&sig=114612073005389583274&page=1&tbnh=144&tbnw=203&start=0&ndsp=15&ved=1t:429,r:3,s:0&biw=1024&bih=653

Video - Plant Growth in Soil:
http://www.youtube.com/v/nlqTUzIUWJ8?version=3

Video - pH Level:
http://www.youtube.com/v/6aC-WTAWgOg

Picture - Coniferous tree:
http://www.google.ca/imgres?imgurl=http://images.pictureshunt.com/pics/b/big_evergreen_trees-11896.jpg&imgrefurl=http://www.free-extras.com/search/1/evergreen%2Btree.htm&usg=__9mgK9d_D89Wyu-4lljh3fcUSLks=&h=421&w=500&sz=49&hl=en&start=1&zoom=1&tbnid=V60K44ryRpCQLM:&tbnh=130&tbnw=154&ei=bZATT73zCYXVgAey2ODXAw&prev=/search%3Fq%3Dparts%2Bof%2Bplants%26hl%3Den%26sa%3DX%26biw%3D1024%26bih%3D653%26tbs%3Dsimg:CAQSYhpgCxCo1NgEGgIICQwLELCMpwgaOQo3CAESEfwD9gMQEvcDBo0E8gP4A_10DGiDJ9UdyaoM7pfq49Yk4eIRzx4KtulC9i0q8yDvt-Mc1WgwLEI6u_1ggaCgoICAESBBOuSDgM%26tbm%3Disch&itbs=1&iact=rc&dur=543&sig=114612073005389583274&page=1&ved=1t:429,r:0,s:0&tx=92&ty=59&biw=1024&bih=653

Picture - Cactus:
http://www.google.ca/imgres?q=cactus&hl=en&tbm=isch&tbnid=FPwLMwMkooe_bM:&imgrefurl=http://260days.ca/%3Fattachment_id%3D854&docid=LG4KSMOU2N08bM&imgurl=http://260days.ca/wp-content/uploads/2011/04/cactus.jpg&w=427&h=576&ei=opATT8mXEo6-gAeH4rDcAw&zoom=1&iact=hc&vpx=269&vpy=160&dur=678&hovh=257&hovw=190&tx=105&ty=115&sig=114612073005389583274&page=1&tbnh=135&tbnw=97&start=0&ndsp=17&ved=1t:429,r:1,s:0&biw=1024&bih=653

Picture - CO2
http://www.google.ca/imgres?q=co2&um=1&hl=en&sa=N&tbm=isch&tbnid=CfKxydnzaxEL2M:&imgrefurl=http://www.inquisitr.com/178722/co2-emissions-will-help-fight-off-ice-age-research/&docid=x91SSCo4Ze7bQM&imgurl=http://www.inquisitr.com/wp-content/2012/01/CO2-Emissions.jpg&w=570&h=330&ei=cY4TT6mzGInAgAfTurW9Aw&zoom=1&iact=rc&dur=179&sig=114612073005389583274&page=1&tbnh=104&tbnw=179&start=0&ndsp=15&ved=1t:429,r:2,s:0&tx=22&ty=30&biw=1024&bih=653