Biotic and Abiotic factors

An ecosystem is the area where living organisms and non-living conditions interact with each other.

Why do we need to maintain biodiversity?
Aesthetic - Artists, musicians and writers get inspired by areas with high biodiversity. It makes people happy.
Economic - Resources are used for medicines, etc and used for trading. Areas rich in diversity are thriving with tourism.
Ecological - Important for keystone species and maintains ecosystems and habitats.

Abiotic factors

Soil pH - Causes soil erosion if increased. Any change can disrupt enzymes which intern affects metabolism.
Temperature - Species will migrate away from the area to warmer/cooler climates if they change. Also can cause flooding due to ice melting, etc. It also affect enzymes and metabolic reactions. Temperature changes causes a change in seasonal species movement. Also it can trigger early migration as well as blossoming and leaf fall.
Light intensity - Affects photosynthesis. Plants grow taller and with bigger leaves to maximise sunlight intake in densely populated areas.
Humidity - Increased humidity encourages bacteria and fungi growth which causes disease.
Oxygen - This is in terms of water. Moving water contains more oxygen. The colder the water, the more oxygen it has. Water logging is a problem for organisms too.
Edaphic (soil) - There are three types of soil: clay, loam and sandy. Clay: contains very fine particles which clump together. Loam: good for growing plants. It contains different sized particles ideal for growth. Sandy: Well separated particles, easily eroded.

Biotic factors

Disease - Food chain disruption.
Invasive species - Introduces disease. They create competition, compete with native species. Such as shrimp in Grafham, red squirrels, and goats in the Galapagos.
Reproduction - More species, more competition for mates, food and territory.