What are each stages of the food chain known as?
Trophic levels
How is energy mainly lost in a food chain?
Respiration, excretion and heat
What’s the difference between an abiotic and biotic environment?
Abiotic = non living (water, light, warmth, humidity) Biotic = living (plants, animals)
What’s an autotroph?
A plant that’s capable of producing its own food through photosynthesis
What’s succession?
The succession of vegetation as it adapts to environmental changes
What’s climatic climax?
Achieved when the largest, most dominant species that the environment will allow are established and the vegetation is in a state of equilibrium with its environment
What’s a sere?
A stage in this sequence of colonisation by which the vegetation develops over a period of time
What’s a prisere?
A complete sequence of events beginning with the first plants to occupy the area and finishing with the climatic climax vegetation
What is primary succession?
Occurs in lifeless, extreme areas (volcanic flows, sand dunes)
What’s secondary succession?
Occurs in areas where existing ecosystem has been removed but soil and nutrients remain and succession can begin again (rainforest clearance, burning of heathland vegetation on dunes)
Name the 4 types of sere:
Lithoseres - develop on bare rock
Haloseres - in saline conditions (saltmarsh)
Hydroseres - recently formed ponds and lakes
Psammosere - develops on sand and dune system
Development of a psammosere system requires:
- Supply of sand
- Strong winds to transport sand particles through saltation
- Obstacle to trap sand
What is the brief description of psammosere succession?
- New dunes develop on the foreshore and here the psammosere is in its pioneer stage (Embryo dunes and Yellow dunes)
- Landwards this, on the older, more sheltered dunes the psammosere is in its building stage (Grey dunes and Fixed)
- Furthest inland on the oldest dunes- psammosere reaches climatic stage (Dune heath to climax)
What are the threats to sand dunes by people?
- Interception of long shore drift due to construction of jetties
- Removal of sand for mineral extraction
- Visitor pressure, trampling, bikes, horse riding
- Pollution from agriculture
- Afforestation
- Levelling for industrial development
- Drinking water abstraction
- Conversion into agricultural land
What are the layers of the tropical rainforest?
- Ground vegetation
- Shrub layer (10m)
- Under canopy (15m)
- Canopy (30m)
- Emergent (60-90m)
Some characteristics of plants in the tropical rainforest?
- Plants grow quickly towards sunlight (lianas)
- Drip tip leaves allow water to easily be shed
- Leaves have a large surface area to catch sunlight
- Epiphytes set their roots into the trunks or branches of other plants - reach max sunlight
- Trees grow tall and straight
- Large buttress roots support trees can grow up to 90m and are shallow
What is an urban niche?
A small scale area within an urban location where conditions are favourable for certain species to thrive (may often be alian and invasive rather than native species)
What are disticntive characteristics of urban environments?
- Higher temperatures than in rural areas due to urban heat island
- Less available water supply
- High amounts of disturbance
- High levels of air, water and noise pollution
What’s a corridor habitat?
An area of habitat connecting wildlife populations separated by human activities or structures
What are the environmental factors affecting plants/animals on walls?
- Chemical nature of material
- Rate of weathering
- Cleaning and repair of walls
- Climatic conditions
- Pollution
Name 4 invasive species:
- Oxford Ragwort
- Buddleia
- Japanese Knotweed
- Rhododendron
Why is japanese knotweed so invasive?
- Absorbs pollution
What are ecosystems along routways affected by?
- Construction techniques
- Drainage systems
- Neglect and minimum human management
- Constant linear traffic movements
- Addition of salt
- Pollution
What do ecosystems at the rural-urban fringe consist of (on the rural side and urban side)?
- Mainly ecological niches
- On the rural side: mixture of intensive agriculture, market gardening, hedgerows, pastoral land, small woods, wasteland and golf courses
- On the urban side: new gardens, established gardens, parks, playing fields, roadsides and railways, allotments and school fields
