Actividades humanas y el ecosistema. ppt

Presentacion de actividades humanas y su efecto en el ecosistema - en ingles

1. Human activities & ecosystem

2. Populations Population  group of individuals of the same species living in a given area Populations change as old members die and new members are born. In nature, populations often stay about the same size from year to year.

3. Growth rate However populations can grow or decline very fast  t he change in size of a population over time is called its growth rate Growth rates  can be positive, negative, or neutral. The graph shows the growth rate of the human population  What can you tell about human growth rate?

4. Growth rate What can you tell about these growth rates? What is the common denominator?

5. Growth rate This is also a growth rate  Because the number of members who die may not be able to be renewed when new members are born.

6. Growth rate In order to grow  we need energy, nutrients, and space Energy and nutrients come from food  so… population growth is limited by the amount of food available. Population growth is also limited by space  If the space it’s not sufficient it can’t grow If any of these variables are too limited, a population will not continue to grow

7. Interactions between organisms The interactions among organisms in an ecosystem create a natural balance in their populations. This balance is partly maintained by predator-prey relationships and competition for food. Sometimes a species that doesn’t belong finds its way into a new area

8. Interactions between organisms A new species in an area it’s not theirs  is often called an invasive species. A species is regarded as invasive if it has been introduced to a region where it did not previously occur naturally. Invasive species  can upset the interactions that create the natural balance https://youtu.be/_ZzPM7Dw9Gg?si=ey7b3jS-uNf5xw7H

9. Interactions between organisms Usually invasive species are introduced by…. Guess who? Humans  We usually think that the introduction is helpful to get rid of pests (But nothing works as we want) It can also happen from (accidentally) taking plants from one country to a another where they can rapidly grow and take nutrients from native plants

10. Invasive species Do you know any invasive species from Argentina? Castor (Castor canadensis ) Ardilla de vientre rojo ( Callosciurus erythraeus ) Estornino pinto ( Sturnus vulgaris ) Caracol africano gigante ( Achatina fulica ) Sauce llorón ( Salix babylonica ) Eucalipto ( Eucalyptus globulus )

11. Invasive species Castor (Castor canadensis ) In 1946, ten pairs of beavers, from Canada, were introduced to Tierra del Fuego with the purpose of using them for their fur. Currently its population exceeds 100,000 specimens and has brought many problems, due to being able to disperse quickly, even reaching Chile The beaver gnaws (roe) at the slow-growing trees found in the Fuegian forests  its presence altered the structure of the forest ecosystem, modifying the water regime and also the nutrient dynamics of the forest .

12. Invasive species Ardilla de vientre rojo ( Callosciurus erythraeus ) In 1970 they introduced 10 individuals for its ornamental appeal  However five populations were established in areas of high agricultural activity  Because of intentional or not practices This causes great economic losses due to the consumption of fruits, breaks in irrigation hoses, damage to storage silos and to telephone, electricity and television cables. They also cause a negative impact on native bird populations as they occasionally destroy their nests and consume their eggs.

13. Invasive species Estornino pinto ( Sturnus vulgaris ) The first record of this species in Argentina was in 1987  specifically in the City of Buenos Aires. Over the years it has managed to disperse to the west and north of the country. The invasion of this species results in economic losses, mainly due to its effects on vineyards and more commercial crops. This species also displaces native species since it competes with them for food and the use of nesting holes.

14. Invasive species Caracol africano gigante ( Achatina fulica ) Due to the damage it causes  this species is included in the list of the 100 most harmful invasive species in the world In Argentina  it causes significant losses in agricultural orchards, especially affecting smaller farms. This snail also constitutes a risk to public health, since it carries pathogens associated with meningitis and other human diseases.

15. Invasive species Sauce llorón ( Salix babylonica ) It is normally used to fix soils and stabilize river banks  However, its introduction in Argentina has brought more negative consequences than benefits. This tree can cause obstruction of rivers and streams, modification of the light regime (which causes changes in water temperature), alteration of the availability of nutrients in the river and in the level of the water table, among others.

16. Invasive species Eucalipto ( Eucalyptus globulus ) This large tree consumes excessive water, a resource for which all plants compete. Because of its size the height and dense foliage of the eucalyptus trees prevents the growth of smaller native species, which lowers the diversity of flora and fauna of the place. Also the accumulation of its leaves on the ground increases the risk of fire. However we keep using eucalyptus as one of the most used species for the paper industry,

17. How these invasive species affect the ecosystem?

18. Humedales Humedales transition zones between terrestrial ecosystems and aquatic ecosystems and have a shallow depth  They are close to rivers or lakes essential from providing everything from freshwater supply, and biodiversity to flood control, groundwater recharge and climate change mitigation. They act as a protective barrier against floods, droughts ( sequias ) and other natural disasters  also they are capable of storing more carbon than any other ecosystem..

19. Humedales In Argentina We only have 23 PROTECTED humedales  covering a total area of ​​5,687,651 acres Argentina approved the Convention on humedales in 1991, through Law 23,919

20. Ecological reserve Reserva ecológica costanera norte Humedal  90% Forest  55% Pastureland  43% Data from 2020 N N ND N N N E N E E E E N ND N E E E E E N E E E

21. Ecological reserve Reserva ecológica costanera norte This humedal is on dispute at the moment because it’s not protected by the law And because of a poor lack of judgement in decision making not too long ago they started construction on the reserve to create a gastronomical and social site This greatly affects the humedal and everything around it and we shouldn’t let it happen

22. 10’ Break

23. Manmade problems Pollutants Human activities affect ecosystems in both positive and negative ways One negative effect is pollution. A pollutant is something that causes harm to a living thing

24. Manmade problems Three things often determine how harmful a pollutant is: The pollutant’s ability to cause harm The amount of pollutant in the air, water, or soil How long the pollutant stays in the air, water, or soil

25. Manmade problems The are five major types of pollution: Air pollution Water pollution Soil pollution Light pollution Noise pollution

26. Manmade problems Air pollution Main source is burning of fossil fuels  Vehicle and factory emissions are common sources This burning contributes to the formation of smog  a dense layer of particles that hangs like a cloud over cities and industrial zones. Air pollution can lead to respiratory problems like asthma, lung cancer and chronic bronchitis

27. Manmade problems Sulfur dioxide is an air pollutant Sulfur is a chemical and when is in large amounts in the air, it can make breathing difficult even for healthy people. It also reacts with water in the atmosphere to make acid rain  this type of rain has a lower PH than normal Acid rain can kill trees and harm life in lakes, ponds, and streams. Sulfur dioxide enters the air from fossil fuel power plants, automobiles, and even volcanoes

28. Manmade problems Water pollution Main source is runoff from agricultural fields, industrial sites, or urban areas  They disrupt the water body's natural balance. Agricultural runoff typically includes fertilizer or toxic chemicals  Fertilizer can cause algal blooms (an explosive growth of algae), choking out other plants and decreasing the amount of available oxygen necessary for the survival of other species.

29. Manmade problems Water pollution Raw sewage  When sewage gets into the drinking water supply, serious stomach and digestive issues may result, and the spread of diseases such as typhoid or dysentery. Trash  Improperly disposed of items, such as plastic bags, fishing line, and other materials may accumulate in the water and lead to the premature death of animals that get tangled within the garbage.

30. Manmade problems Soil pollution This type of contamination prevents growth of natural life  Farming and wildlife. Main cause due to industrial sources or the improper disposal of toxic chemical substances. For example  asbestos, lead, PCBs, pesticides/herbicides This can lead to loss of agriculture as well as poisoning of the land and nearby water.

31. Manmade problems Light pollution Light pollution refers to the large amount of light produced by most urban and other heavily-populated areas. Light pollution prevents citizens from seeing features of the night sky and has also been shown to impede the migration patterns of birds and the activities of nocturnal animals.

32. Manmade problems Noise pollution Noise pollution typically refers to human-made noises that are either very loud or disruptive in manner. This type of pollution has been shown to impact the movement of sea mammals  such as dolphins and whales also impacts the nesting success of birds.

33. Manmade problems Mercury is also a pollutant Mercury is an element that can be found naturally in an ecosystem However h uman activities like industry also cause the release of mercury into the environment The mercury is taken in by members of an ecosystem and it builds up in their bodies When the amount of mercury in a living organism gets high enough, the animal or plant can die.

34. Manmade problems Mercury is also a pollutant Mercury is commonly found in fish  Because it’s stored in the fatty tissues of the fish over its entire lifetime Because it doesn’t get stored the level of the mercury in the fish may be thousands of times higher than the level of the mercury in the water  This is called biomagnification

35. Manmade problems Toxins Human activities sometimes create toxic pollutants called toxins High concentrations may impact living things  they can cause slowed growth, decreased reproduction, and even death . Some toxins end up in lakes and oceans  and f ood chains concentrate some toxic pollutants ( biomagnification )

36. Manmade problems Toxins Can be passed on to offspring When carnivores eat many herbivores, they accumulate even higher levels of toxins in their tissues Secondary carnivores  who prey on other carnivores, can accumulate dangerous levels of toxins  These toxins can sometimes be passed on to their young.

37. Transgenerational effect of toxins

38. Pesticides The environmental effects of pesticides describe the broad series of consequences of using pesticides. The negative effects of pesticides are not just in the area of application  Runoff and pesticide drift can carry pesticides into distant aquatic environments or other fields, grazing areas, human settlements and undeveloped areas.

39. What is Monsanto? The Monsanto Company was an American agrochemical and agricultural biotechnology corporation Monsanto's best-known product is Roundup, a glyphosate-based herbicide, developed in the 1970s. Later, the company became a major producer of genetically engineered crops

40. What is Monsanto? Glyphosate Non-selective herbicide  it kills any type of plant it comes into contact with, attacking the proteins responsible for its growth. The exposure to this component has been linked to an increased in health problems, like:     - Cancer     - Reproductive problems     - Neurological diseases - ALS     - Endocrine disruption

41. What is Monsanto? The company also manufactured controversial products such as: Insecticide DDT ( banned ) PCBs ( banned ) Agent Orange ( banned )  used in the Vietnam War by the United States and responsible for the deaths of hundreds of thousands of people and the destruction or damage to millions of hectares of forest and crops.

42. Thanks !