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09 effects on freshwater systems-1

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Freshwater ecosystems are particularly vulnerable to climate change. Temperature changes can influence freshwater ecosystems in many ways, affecting entire food webs as organisms and their prey and predators all have preferred temperature ranges. As temperatures increase, organisms may migrate upstream or deeper in search of cooler temperatures, but this decreases available habitat. With less habitat, populations decline as organisms don't reproduce as much. For organisms unable to migrate, increased temperatures cause higher metabolism and food demands, as well as changes to sex ratios, increased toxin uptake, and effects like eutrophication. Warmer temperatures also reduce water levels in streams and lakes through greater evaporation and plant water uptake.

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Effects on Freshwater Ecosystems Freshwater ecosystems are particularly vulnerable to change because they tend to be individually small, and relatively isolated. Affected in several ways, but primarily through temperature and stream flow.
Freshwater Ecosystems Temp. Temperature changes can influence freshwater ecosystems in many different ways. All organisms have a preferred temperature range.
Warming climate influences not just the organism itself, but also its prey and predators. Thus entire food web dynamics are affected.
Freshwater Ecosystems Temp. If temperature changes, organisms will migrate towards their preferred temperature if they can .
Freshwater Ecosystems Temp. With warming, organisms will migrate upstream towards higher elevations (cooler). Less habitat area upstream!
Freshwater Ecosystems Temp. With warming, organisms will migrate deeper (cooler). Less habitat area at depth!
Freshwater Ecosystems Temp. Decreased habitat results in unhappy fish they dont reproduce as much. Trout habitat could shrink 30-40%, and for some species of salmon by as much as 50%.
Freshwater Ecosystems Temp. For organisms that cant migrate, increased temperature causes increased metabolism.
Freshwater Ecosystems Temp. For organisms that cant migrate, increased temperature causes increased metabolism.
Freshwater Ecosystems Temp. Increased metabolism comes with other demands food!
Freshwater Ecosystems Temp. Changing water temperatures can also change the sex ratio of reptiles, amphibians, fish, and insects.
Freshwater Ecosystems Temp. Increased metabolism increases the uptake of toxins that bioaccumulate.
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Freshwater Ecosystems Temp. Temperature changes can cause indirect biologic effects as well. Eutrophication.
Freshwater Ecosystems Temp. Surface warming causes surface water to become less dense harder to mix downward. Warmer water also holds less dissolved oxygen to begin with.
Freshwater Ecosystems Stream Flow Warmer temperatures will increase transpiration causing plants to uptake and release more water. Less is available for runoff or groundwater input to lakes and streams.
Freshwater Ecosystems Stream Flow Even though precipitation is expected to increase at mid-latitudes, it is thought that increased transpiration due to warming may offset the increase.
Freshwater Ecosystems Stream Flow More runoff at high latitudes as more precipitation as rain than snow. Remobilization of sediments.
Freshwater Ecosystems Stream Flow Increased fluvial erosion at high latitudes.
Freshwater Ecosystems Stream Flow Mid- and low-latitude streams and lakes likely to have less available water. - more winter precipitation as rain (more will runoff than be stored). - less precipitation and/or greater evaporation during summer result in lower water levels. - altering of lake chemistry by ion concentration.
Freshwater Ecosystems Sea Level Sea level rise will stress coastal wetlands.
Freshwater Ecosystems Sea Level

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09 effects on freshwater systems-1

  • 1. Effects on Freshwater Ecosystems Freshwater ecosystems are particularly vulnerable to change because they tend to be individually small, and relatively isolated. Affected in several ways, but primarily through temperature and stream flow.
  • 2. Freshwater Ecosystems Temp. Temperature changes can influence freshwater ecosystems in many different ways. All organisms have a preferred temperature range.
  • 3. Warming climate influences not just the organism itself, but also its prey and predators. Thus entire food web dynamics are affected.
  • 4. Freshwater Ecosystems Temp. If temperature changes, organisms will migrate towards their preferred temperature if they can .
  • 5. Freshwater Ecosystems Temp. With warming, organisms will migrate upstream towards higher elevations (cooler). Less habitat area upstream!
  • 6. Freshwater Ecosystems Temp. With warming, organisms will migrate deeper (cooler). Less habitat area at depth!
  • 7. Freshwater Ecosystems Temp. Decreased habitat results in unhappy fish they dont reproduce as much. Trout habitat could shrink 30-40%, and for some species of salmon by as much as 50%.
  • 8. Freshwater Ecosystems Temp. For organisms that cant migrate, increased temperature causes increased metabolism.
  • 9. Freshwater Ecosystems Temp. For organisms that cant migrate, increased temperature causes increased metabolism.
  • 10. Freshwater Ecosystems Temp. Increased metabolism comes with other demands food!
  • 11. Freshwater Ecosystems Temp. Changing water temperatures can also change the sex ratio of reptiles, amphibians, fish, and insects.
  • 12. Freshwater Ecosystems Temp. Increased metabolism increases the uptake of toxins that bioaccumulate.
  • 13. 油
  • 14. Freshwater Ecosystems Temp. Temperature changes can cause indirect biologic effects as well. Eutrophication.
  • 15. Freshwater Ecosystems Temp. Surface warming causes surface water to become less dense harder to mix downward. Warmer water also holds less dissolved oxygen to begin with.
  • 16. Freshwater Ecosystems Stream Flow Warmer temperatures will increase transpiration causing plants to uptake and release more water. Less is available for runoff or groundwater input to lakes and streams.
  • 17. Freshwater Ecosystems Stream Flow Even though precipitation is expected to increase at mid-latitudes, it is thought that increased transpiration due to warming may offset the increase.
  • 18. Freshwater Ecosystems Stream Flow More runoff at high latitudes as more precipitation as rain than snow. Remobilization of sediments.
  • 19. Freshwater Ecosystems Stream Flow Increased fluvial erosion at high latitudes.
  • 20. Freshwater Ecosystems Stream Flow Mid- and low-latitude streams and lakes likely to have less available water. - more winter precipitation as rain (more will runoff than be stored). - less precipitation and/or greater evaporation during summer result in lower water levels. - altering of lake chemistry by ion concentration.
  • 21. Freshwater Ecosystems Sea Level Sea level rise will stress coastal wetlands.