Plant matters: Is photosynthesis the best defense against climate change? | Grist
Photosynthesis. 3. Which conditions are best for decomposition to happen quickly? Warm, moist conditions. Cold, moist conditions. Warm, dry conditions Ecological relationships and energy flow (CCEA). The carbon cycle and decomposition (CCEA); Global warming, human Education Quizzes: Biology SUBSCRIPTION. Review Quiz. Which statement Global temperatures depend on the total amount of carbon on Earth. c. Human actions During which stages would you expect global warming to dominant? a. Stages 1 and 2 b. Predation c. Photosynthesis. Photosynthesis: Photosynthesis, process by which green plants and certain other organisms Demystified · Quizzes · Galleries · Lists · On This Day · Biographies · Newsletters history, and this phenomenon is expected to have major implications on Earth's climate. . Light intensity and temperature.
It was a truly massive heap, nearly the length of a football field, five feet tall and 10 feet wide, and a second equally large pile lay nearby. It all belonged to Cornell University, one of the powerhouses of agricultural research in the United States.
Sure enough, although it was a cool, cloudy day, my forearm soon felt almost uncomfortably warm. The author, investigating the smoking hot compost at Cornell.
Compost is but one of the materials that can be used to produce biochar, a substance that a small but growing number of scientists and private companies believe could enable extraction of carbon dioxide from the atmosphere at a meaningful scale. Like compost, all of these materials contain carbon: The plants inhaled it, as carbon dioxide, in the process of photosynthesis.
Inserting biochar in soil therefore has the effect of removing carbon dioxide from the atmosphere and storing it underground, where it will not contribute to global warming for hundreds of years.
BBC Bitesize - GCSE Biology (Single Science) - The carbon cycle and decomposition (CCEA) - Test
This approach would take advantage of a physical reality often overlooked in climate policy discussions: By contrast, biochar and other photosynthesis-based methods of carbon extraction take advantage of natural processes that already help to regulate planetary health. Historically it was fire that helped drive the carbon cycle on Earth, burning plants and trees and returning their embedded carbon to the soil in the form of charcoal. Contemporary societies have greatly restricted the use of fire.
Producing biochar is a way to begin restoring the proper balance by catalyzing soil regeneration through the addition of biochar to soils. Unlike CCS, biochar does not assume continued burning of fossil fuel. Rather, its feed stocks are waste materials that normal agricultural and forestry production methods leave behind in great quantities: Get Grist in your inbox Always free, always fresh.
But Monbiot unfairly tarred all biochar supporters with the same brush, as he later admitted. In fact, Lehmann has always clearly stated that he did not favor the plantation approach. Senate that human activities were raising global temperatures. At Cornell, he is producing biochar in a kiln whose shiny metal pipes and funnels make it look more like part of an electric power station than a cutting-edge agricultural device.
This is the kiln, manufactured by Full Circle, where Lehmann of Cornell produces biochar. There are more ecologically efficient uses for that compost heap, he explains. Rather, Lehmann will use post-harvest cornstalks from other Cornell agricultural research plots. Adding biochar to soil therefore is also a form of climate change adaptation: There is no one-size-fits-all technology for extracting carbon and sequestering it in soil, mainly because local circumstances, both social and physical, differ around the world.
These fuels not only provide much of the energy used in factories, homes, and transportation but also serve as the raw material for plastics and other synthetic products. Unfortunately, modern civilization is using up in a few centuries the excess of photosynthetic production accumulated over millions of years.
Consequently, the carbon dioxide that has been removed from the air to make carbohydrates in photosynthesis over millions of years is being returned at an incredibly rapid rate. Requirements for food, materials, and energy in a world where human population is rapidly growing have created a need to increase both the amount of photosynthesis and the efficiency of converting photosynthetic output into products useful to people.
One response to those needs—the so-called Green Revolutionbegun in the midth century—achieved enormous improvements in agricultural yield through the use of chemical fertilizerspest and plant- disease control, plant breedingand mechanized tilling, harvesting, and crop processing.
This effort limited severe famines to a few areas of the world despite rapid population growthbut it did not eliminate widespread malnutrition.
Moreover, beginning in the early s, the rate at which yields of major crops increased began to decline. This was especially true for rice in Asia. Rising costs associated with sustaining high rates of agricultural production, which required ever-increasing inputs of fertilizers and pesticides and constant development of new plant varieties, also became problematic for farmers in many countries.
A second agricultural revolutionbased on plant genetic engineeringwas forecast to lead to increases in plant productivity and thereby partially alleviate malnutrition. However, such traits are inherently complex, and the process of making changes to crop plants through genetic engineering has turned out to be more complicated than anticipated.
The carbon cycle and decomposition (CCEA)
In the future such genetic engineering may result in improvements in the process of photosynthesis, but by the first decades of the 21st century, it had yet to demonstrate that it could dramatically increase crop yields. Another intriguing area in the study of photosynthesis has been the discovery that certain animals are able to convert light energy into chemical energy. The emerald green sea slug Elysia chloroticafor example, acquires genes and chloroplasts from Vaucheria litorea, an alga it consumes, giving it a limited ability to produce chlorophyll.
When enough chloroplasts are assimilatedthe slug may forgo the ingestion of food. General characteristics Development of the idea The study of photosynthesis began in with observations made by the English clergyman and scientist Joseph Priestley.
Global warming, human activity and biodiversity (CCEA)
Priestley had burned a candle in a closed container until the air within the container could no longer support combustion. He then placed a sprig of mint plant in the container and discovered that after several days the mint had produced some substance later recognized as oxygen that enabled the confined air to again support combustion. He also demonstrated that this process required the presence of the green tissues of the plant. Gas-exchange experiments in showed that the gain in weight of a plant grown in a carefully weighed pot resulted from the uptake of carbon, which came entirely from absorbed carbon dioxide, and water taken up by plant roots; the balance is oxygen, released back to the atmosphere.
Almost half a century passed before the concept of chemical energy had developed sufficiently to permit the discovery in that light energy from the sun is stored as chemical energy in products formed during photosynthesis.
Overall reaction of photosynthesis In chemical terms, photosynthesis is a light-energized oxidation—reduction process.