What makes an ecosystem fragile?

1) Short and highly interconnected food webs.
2) Harsh climate
3) Proportional impact
4) Recovery rates

1. Short and highly interconnected food webs

One small change affects the whole ecosystem (knock-on).

2. Harsh Climate

• Diurnal range (freezing nights)
• Temperature range (up to 50°C)
• Less than 100mm rainfall (unreliable)
• High winds (abrasion)

3. Proportional Impact

• Arid NPP= 30-200g/m2/yr
• Biomass very low

NPP= the amount of biomass added to an ecosystem in a given time.

Biomass= the combined weight of all living matter in an ecosystem.

4. Recovery rates

Very long, even limited damage can have long-lasting impacts.