Population Growth in the Epipelagic
A population increase when:
r (rate of growth)=(BR+I) - (DR+E) It has a specific maximum capacity or carrying capacity N= number of individuals in a population r= growth rate K= carrying capacity |
"r selected"
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The image below demonstrates the type 1,2,3 survival rates in a life span. Humans and K are able to survive longer, then the coral or birds, and at last is plants and other r species
Annual Cycles
Each spring, in temperate seas and lakes around the globe, planktonic populations of diatoms advantage of the increasing amounts of light and an abundance of nutrients. The diatoms explode as they survive, mature, and reproduce. Populations of zooplankton respond to the "spring blooms" of diatoms, because they consume these organisms allowing their numbers to increase. Later in the annual cycle, the numbers of individuals in the diatom and zooplankton populations decrease, responding to decreases in sunlight and nutrients and increases in competition and predation. Populations are dynamic they can increase, decrease, while responding to changes in the biotic and abiotic environments.
Each spring, in temperate seas and lakes around the globe, planktonic populations of diatoms advantage of the increasing amounts of light and an abundance of nutrients. The diatoms explode as they survive, mature, and reproduce. Populations of zooplankton respond to the "spring blooms" of diatoms, because they consume these organisms allowing their numbers to increase. Later in the annual cycle, the numbers of individuals in the diatom and zooplankton populations decrease, responding to decreases in sunlight and nutrients and increases in competition and predation. Populations are dynamic they can increase, decrease, while responding to changes in the biotic and abiotic environments.
When there is an increase in diatoms (left) during the spring blooms, the zooplankton (right) have a larger food abundance concluding with their population increasing
Human Impacts
Ocean acidification is the name given to the ongoing decrease in the pH of the Earth's oceans, caused by the uptake of anthropogenic carbon dioxide from the atmosphere. About 30–40% of the carbon dioxide released by humans into the atmosphere dissolves into the oceans, rivers and lakes. To maintain chemical equilibrium, some of it reacts with the water to form carbon acid. Some of these extra carbon acid molecules react with a water molecule to give a bicarbonate ion, a salt of carbonic acid, an acid carbonate, as sodium bicarbonate, and a hydronium ion, is a water molecule with an extra hydrogen and it has and extra positive charge, increasing the ocean's acidity. Between 1751 and 1994 surface ocean pH is estimated to have decreased from approximately 8.25 to 8.14, representing an increase of almost 30% in H+ ion concentration in the world's oceans. These rising levels of acidity, along with the effects of global warming, could affect the ability of the oceans to absorb greenhouse gases and is threatening ecosystems, sea creatures and their food supplies.
This increasing acidity is thought to have a range of direct undesirable consequences such as depressing metabolic rates in jumbo squid and depressing the immune responses of blue mussels. Other chemical reactions are also triggered which result in an actual net decrease in the amount of carbonate ions available. In the oceans, this makes it more difficult for marine calcifying organisms, such as coral and some plankton, to form biogenic calcium carbonate, and structures become vulnerable to dissolution. Thus, ongoing acidification of the oceans also poses a threat to the food chains connected with the oceans. As members of the InterAcademy Panel, 105 science academies have issued a statement on ocean acidification. The statement recommends that by 2050, global CO2 emissions be reduced by at least 50%, compared to the 1990 level.
Over Fishing
What caused this situation?
Greater and greater demand, an increasing population, total absence or non-application of regulations, short-term vision and all of it made worse by:
- Drifting and lost nets which destroy species unnecessarily
- Trawling: a non-selective fishing method using huge nets that catch all types of fish and sea creatures, and deep-sea trawlers that destroy numerous ecosystems
- By catch: a huge wastage due to the absence of respectful fishing practices (size of the mesh of the nets, selective methods according to size and species), and complete lack of concern
- Technology: today’s fishing vessel has a capacity almost 100 times greater than that of the 1950s
- Pirate or illegal fishing: pillage of fish stocks in violation of the breeding season and in coastal waters
- Aquaculture: empties the oceans. On average it requires 4kg of fish caught in the ocean to obtain 1kg of farmed fish!
The solutions:
- Tighten controls by introducing trade measures against illegal, non-declared or unregulated fishing practices: the cost of this illicit fishing is somewhere between 10 and 23.5 billion dollars a year
- Set up a world register of fishing vessels. And assign a single identification number for the life of that particular vessel, regardless of changes in its ownership or flag. This will facilitate the work of the maritime police fighting against illegal fishing
- Establish rules like catch quotas or temporary prohibition to allow reproduction to take place, and for rest periods of the biodiversity - Reduce the number of ships and the fishing capability
- Use selective and durable fishing practices : line-fishing for example
- Manage fisheries using an ecosystem approach and not only by quota
- Encourage marine protected areas and artificial reefs
- Drastically reduce our consumption of threatened species
Ocean acidification is the name given to the ongoing decrease in the pH of the Earth's oceans, caused by the uptake of anthropogenic carbon dioxide from the atmosphere. About 30–40% of the carbon dioxide released by humans into the atmosphere dissolves into the oceans, rivers and lakes. To maintain chemical equilibrium, some of it reacts with the water to form carbon acid. Some of these extra carbon acid molecules react with a water molecule to give a bicarbonate ion, a salt of carbonic acid, an acid carbonate, as sodium bicarbonate, and a hydronium ion, is a water molecule with an extra hydrogen and it has and extra positive charge, increasing the ocean's acidity. Between 1751 and 1994 surface ocean pH is estimated to have decreased from approximately 8.25 to 8.14, representing an increase of almost 30% in H+ ion concentration in the world's oceans. These rising levels of acidity, along with the effects of global warming, could affect the ability of the oceans to absorb greenhouse gases and is threatening ecosystems, sea creatures and their food supplies.
This increasing acidity is thought to have a range of direct undesirable consequences such as depressing metabolic rates in jumbo squid and depressing the immune responses of blue mussels. Other chemical reactions are also triggered which result in an actual net decrease in the amount of carbonate ions available. In the oceans, this makes it more difficult for marine calcifying organisms, such as coral and some plankton, to form biogenic calcium carbonate, and structures become vulnerable to dissolution. Thus, ongoing acidification of the oceans also poses a threat to the food chains connected with the oceans. As members of the InterAcademy Panel, 105 science academies have issued a statement on ocean acidification. The statement recommends that by 2050, global CO2 emissions be reduced by at least 50%, compared to the 1990 level.
Over Fishing
What caused this situation?
Greater and greater demand, an increasing population, total absence or non-application of regulations, short-term vision and all of it made worse by:
- Drifting and lost nets which destroy species unnecessarily
- Trawling: a non-selective fishing method using huge nets that catch all types of fish and sea creatures, and deep-sea trawlers that destroy numerous ecosystems
- By catch: a huge wastage due to the absence of respectful fishing practices (size of the mesh of the nets, selective methods according to size and species), and complete lack of concern
- Technology: today’s fishing vessel has a capacity almost 100 times greater than that of the 1950s
- Pirate or illegal fishing: pillage of fish stocks in violation of the breeding season and in coastal waters
- Aquaculture: empties the oceans. On average it requires 4kg of fish caught in the ocean to obtain 1kg of farmed fish!
The solutions:
- Tighten controls by introducing trade measures against illegal, non-declared or unregulated fishing practices: the cost of this illicit fishing is somewhere between 10 and 23.5 billion dollars a year
- Set up a world register of fishing vessels. And assign a single identification number for the life of that particular vessel, regardless of changes in its ownership or flag. This will facilitate the work of the maritime police fighting against illegal fishing
- Establish rules like catch quotas or temporary prohibition to allow reproduction to take place, and for rest periods of the biodiversity - Reduce the number of ships and the fishing capability
- Use selective and durable fishing practices : line-fishing for example
- Manage fisheries using an ecosystem approach and not only by quota
- Encourage marine protected areas and artificial reefs
- Drastically reduce our consumption of threatened species
These image shows all the pollution in the ocean and how much damage humans have caused to the ocean surface.
Alexis's notes.
Jennifer did the annual cycles.
Jennifer typed it and retrieved the pictures.
Jennifer did the annual cycles.
Jennifer typed it and retrieved the pictures.