Ecological catastrophes
Eg Mexico dead zone has become hypoxic meaning fish die from lack of oxygen
Ddt and dde = biomagnification
DDE which affects size and structure of egg shells. California condour extiunct
Weaker thinner egg shells break meaning less reproduction meaning extinction and
clafornia condour had very low maturation rate.
Increased insecticeds meant increased evolution for the pest via adaptation therefore
require more and more toxicity this cuases a cycle.
Bees act as pollinators and make fruits and veg.
Neonicotinoid kilsls good and bad bugs. Honeybees prefers this even tho kills them. This is
still increaseinhg. Reduces sperm viability fo males.
Ecosystem services are required for us. E..g food web support, nutrient cycling and soil
formation and quality and water purification.
Muts find solution or alternative before changing .
Freshwater loss
e.g. shrinking or aral sea. 1989-2009
animals died from the grass being salty they hit their heads against the land .
is now 10% of it original size
compelte loss of species and river deltas
there were toxic dust storms causing cancer, crops were destroyed by the dust. All cost was
1 billion dollars would be more now.
Local climate change happened. Since it was a large body of water it caused coastal breeze
which is cold and these winds were from the arctiuc Siberia and happened in the winter all
this led to desertification.
20/24 fish disappeared and annual catch went from 48000 to none. Dried seabed and its
chemical composition prevented plant growth and a loss of ground water meant dramatic
decline in plant communities
Were 173 vertebrate species now 38
Cant drink from delta areas
Added fish didn’t know were invasive causing worse deceline
Restoration plan is very hard because of climate change.
Human alterations cause consequences, all parts of the food chain ,ust be considred, and
some changes are more catastrophic than we relaise.
Murray darling roiver basin its happening as well due to unsustainable water extraction. Fish
cnat even swim. Shouldn’t plant crops that need more eater than able to be prodicvivde for
e..g cotton.
Caspian see will become same as aspral
Central north America cleared depep rooted foir shoprt rooted and its crop rotation was too
short
Bison is keystones species 60 million was hunted. These turnedover nutrients. They increase
habitat hetergenity. Grazed increased mineraliseation and nitriofcation brings fertility in
soils. Ungraed did opposite,
Prairie dogs also turned over soils.