geography-paper 1 physical

what is a natural hazard?

give 2 examples

a natural event that threatens people, property, environment

earthquakes

volcanic eruptions

what causes tectonic hazards?

movement of tectonic plates, driven by heat within the earth

move apart, collide or slide causing natural hazards

difference between constructive and destructive plate boundaries

destructive, plates move towards each other

oceanic plate may subduct beneath another plate causing natural hazards

constructive, plates move apart. magma rises through the gap, cools and forms new crust

difference between primary and secondary effects of a tectonic hazard

primary effects happen immediately

secondary effects happen later

case study: what happened during the nepal earthquake

-in 2015

-a LIC

-around 9000 people died

-3million left homeless

- infrastructure damaged

-landslides caused further disruptions

what causes climate change

human activities such as burning fossil fuels

deforestation, increase greenhouse gas emissions house gases, trapping heat in atmosphere

climate change prevented by

mitigation- reduce emissions through renewable energy

adaptation- prepare impacts through flood defences, drought resistant crops and improved water management

an ecosystem

a community of biotic interacting with each other and abiotic components

nutrient cycle

movement of nutrients between vegetation litter and soil. plants absorb nutrients from soil. animals obtain by them by feeding. decomposers return nutrients when organisms die.

characteristics of a tropical rainforest

• high temperatures throughout the year

• heavy rainfall all year

• dense vegetation and high biodiversity

• layered vegetation including emergent trees, canopy, under-canopy

biodiversity

means the variety of living organisms in an area

how are tropical rainforests adapted to their environment?

drip tip leaves allow water to run off

buttress roots support tall trees in shallow soils

large leaves in the under-canopy help capture limited light.

case study: what are the causes and impacts of deforestation in the amazon rainforest?

cattle ranching, commercial farming, logging, mining, road construction, energy development

impacts of deforestation

habitats destroyed reducing biodiversity

trees release stored carbon when burned or decomposed

exposed soils are more vulnerable to erosion

water cycle is disrupted because less water returns to the atmosphere through transpiration

how can tropical rainforests be managed sustainably

selective logging removes chosen trees rather than clearing entire areas

replanting replaces felled trees

ecotourism creates income whilst encouraging conservation

international agreements and laws

education reduce pressure on deforestation

characteristics of a hot desert

low rainfall

high temperatures

sparse vegetation

water is limited

temperatures fall significantly at night

aridity

how are sloths adapted to the rainforest

long curved claws help them hang from branches

long limbs help them move through trees

slow movement conserves energy

spider monkeys

prehensile tails act like an extra limb

helps them grip branches and balance as they move through canopy

long arms and legs helps swing between branches and move quickly through the trees to find food

hook like hands help grip branches as they climb and swing

sahara desert camel adaptations

hump stores fat which breaks down energy

wide feet so it can spread it’s weight in the sand and walk

2 sets of long lashes help protect it’s eyes from blowing sand

opportunities in sahara desert

mineral extraction including oil and gas in some areas

solar energy because of intense sunlight

tourism