Ecological Harm on Plants
Invasive Plants
Invasive plant species, commonly introduced by humans, are devastating for the local plant species and animals. One such invasive plant species to North America is Houndstongue. Houndstongue was accidently introduced to North America from contaminated seeds from Eurasia, and is very toxic to grazing cattle and local plants in the Midwest (“Invasive Species”). The plant poisons any cattle that happen to chew on it and any nearby plants through its roots. Other invasive plant species to North America, such as Air Potato and Russian Knapweed, smother and over crowd local plants (“Invasive Species”). Those invasive plant species completely take over miles of local vegetation; which leaves animals that graze off of the local vegetation with little to no food left in that area. Those animals are forced to either leave that particular area in search of more food, or stay in that area and face the possibility of starvation. Both possibilities force the local ecosystem to dramatically change from losing vital species in its food web. Invasive species may thrive in their new areas, but the local ecosystem will suffer greatly from it. |
Plant Pathogens
With over 1000 viral plant pathogens and over 100 bacterial pathogens(Gergerich & Dolja), they are a major threat to plant species. Plants are commonly infected by pathogens through contact between other plants or contact with vectors. Vectors are small organisms such as arthropods and nematodes that carry viral pathogens from one plant, and then inject another plant with their needle like mouths to feed (Gergerich & Dolja). The injection passes the pathogen from the vector to the plant. Common symptoms from these pathogens include blights, rotting, abnormal growths, absence of nectar, weakened or destroyed fruit, or death of the plant (Vidaver & Lambrecht). These symptoms can have devastating effects on the plants ecosystem. Hummingbirds and bees would not be able to use the plant's nectar and spread pollen, resulting in the decline of both of their populations. In addition, plant pathogens are devastating on human agricultural and economy. Annually, cacao swollen shoot virus is responsible for the loss of 50,000 tons ($28 million) of cocoa beans in Africa (Gergerich & Dolja). Rice tungro virus causes the loss of about $1.5 billion dollars worth of rice annually in Asia, and tomato spotted wilt virus is responsible for the loss of $1 billion dollars worth of tomatoes, peanuts, and tobacco annually worldwide (Gergerich & Dolja). The dramatic losses of these plants not only cause harm on the plants, but also greatly harm human food production. |
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Human Impact
Humans, especially in the last few centuries, have heavily damaged plants and their ecosystems. Humans are responsible for introducing some of the most harmful plant pathogens to North America. One such pathogen is chestnut blight or cryphonectria parasitica. Chestnut blight was introduced from Europe by an infected cargo of wood (Yopp). The chestnut blight ravaged the North American chestnut trees populations into a shadow of their former selves, since they had no natural resistance to the fungi. The declining chestnut population reduced shade and cover for prey and predators, wood production, and food sources, especially for wild turkeys (who also suffered a decline in population) (Yopp). However, one of the most devastating effects on plants and their ecosystems is pollution from fossil fuels. Air pollutants, such as carbon dioxide and methane, block plant openings (stomatas) that are vital for producing oxygen (Rogers). The lack of pollutants being taken out of the air and oxygen being produced from plants is devastating for all species that breathe oxygen. With polluted oxygen, health would dramatically decline and may even lead to the disappearance of healthy oxygen. Plants are vital for humans, but we are the ones who are destroying them. |
Works Cited
Gergerich, R., & Dolja, V. (2015). Introduction to Plant Viruses, the Invisible Foe. Retrieved April 21, 2015, from http://www.apsnet.org/edcenter/intropp/PathogenGroups/Pages/PlantViruses.aspx
Invasive Species: Plants. (2015, January 15). Retrieved June 6, 2015, from http://www.invasivespeciesinfo.gov/plants/main.shtml
Pal, K. (2011). Biological Control of Plant Pathogens. Retrieved April 23, 2015, from
http://www.apsnet.org/EDCENTER/ADVANCED/TOPICS/Pages/BiologicalControl.aspx
Rogers, C. (n.d.). The Effects of Pollutants on Plant Structure. Retrieved May 19, 2015, from http://smallbusiness.chron.com/effects-pollutants-plant-structure-17119.html
Vidaver, A., & Lambrecht, P. (2015). Bacteria as Plant Pathogens. Retrieved April 21, 2015, from
http://www.apsnet.org/edcenter/intropp/PathogenGroups/Pages/Bacteria.aspx
Yopp, J. (n.d.). Plant | biology. Retrieved June 6, 2015, from http://www.britannica.com/EBchecked/topic/463192/plant
Gergerich, R., & Dolja, V. (2015). Introduction to Plant Viruses, the Invisible Foe. Retrieved April 21, 2015, from http://www.apsnet.org/edcenter/intropp/PathogenGroups/Pages/PlantViruses.aspx
Invasive Species: Plants. (2015, January 15). Retrieved June 6, 2015, from http://www.invasivespeciesinfo.gov/plants/main.shtml
Pal, K. (2011). Biological Control of Plant Pathogens. Retrieved April 23, 2015, from
http://www.apsnet.org/EDCENTER/ADVANCED/TOPICS/Pages/BiologicalControl.aspx
Rogers, C. (n.d.). The Effects of Pollutants on Plant Structure. Retrieved May 19, 2015, from http://smallbusiness.chron.com/effects-pollutants-plant-structure-17119.html
Vidaver, A., & Lambrecht, P. (2015). Bacteria as Plant Pathogens. Retrieved April 21, 2015, from
http://www.apsnet.org/edcenter/intropp/PathogenGroups/Pages/Bacteria.aspx
Yopp, J. (n.d.). Plant | biology. Retrieved June 6, 2015, from http://www.britannica.com/EBchecked/topic/463192/plant