Types of Ecosystems
Ecosystems cover the entire globe, and there are several ways to classify them based on their common features. The major classification is:
These ecosystems are found on land areas. The main types of terrestrial ecosystems are:
- Tropical Rainforests – Hot and humid forests with high yearly rainfall. Dense growth of broad-leaved evergreen trees. Found in the Amazon basin, Congo basin.
- Temperate Forests – Moderate climatic conditions and rainfall. Mixture of deciduous and coniferous trees. Oak, maple, pine, spruce, fir trees. Found in USA, Canada, Russia.
- Boreal Forests – Cold climatic conditions with snow cover. Mainly coniferous trees like pine, fur, spruce. Found in Alaska, Northern Canada, Scandinavia.
- Tropical Savannas – Warm temperate climate with seasonal drought and rain. Grasses co-exist with scattered trees. African savanna is a major example.
- Temperate Grasslands – Moderate rainfall allowing dense growth of grasses, herbs and shrubs. Prairies of North America, pampas of South America, and steppes of Eurasia examples.
Treeless lands of the Arctic circle with permafrost soil, low winter temperatures and short summers. Mosses, lichens typical plants. Found in the Arctic regions.
Arid regions with very little rainfall. Sparse vegetation mostly shrubs and cacti suited to dry conditions. Found in Sahara, Gobi, Mojave desert areas.
These ecosystems are found in water bodies and can be marine or freshwater systems. Examples include:
- Oceans – Make up marine ecosystems covering 75% of earth’s surface. Coral reefs are diverse aquatic ecosystems within warm ocean waters.
- Lakes and Ponds – Freshwater ecosystems including features like littoral zone, open water zone, benthic zone and more. Lake Superior and Lake Baikal two of the world’s largest lake ecosystems.
- Rivers and Streams – Also freshwater flow systems from upstream segments to downstream floodplains. Amazon river ecosystem in S. America and River Ganges ecosystem in Indian subcontinent.
- Estuaries – Semi-enclosed coastal water bodies with freshwater mixing with sea water from rivers and tides. Serve as transition zone and habitat for unique biota.
These include areas created and modified by human beings for residence, agriculture or other uses. Examples include:
- Crop Plantations: Monocultures of selected crops like rice paddies, wheat farms and more. Among intensively managed agricultural land ecosystems.
- Gardens and Parks: Small assembled ecosystems with a mix of plants, trees, lawns for aesthetic pleasure and recreation.
- Urban Ecosystems: Cities have unique mixes of soil, water and air conditions along with introduced animal and plant species.
Classification by Ellenberg
German ecologist Ellenberg proposed a hierarchical classification system for ecosystems at different scales, from the global to the local level. At the top lies the biosphere, encompassing all ecosystems on Earth. The next tier consists of mega-ecosystems based on broad habitat types such as marine ecosystems in salty seas and oceans; limnic ecosystems in freshwater lakes and rivers; semi-terrestrial wetland ecosystems; purely terrestrial ecosystems on dry land; and human-constructed urban-industrial ecosystems.
Within these mega-ecosystems exist macro-ecosystems defined by geography and climate, like forests, deserts, and grasslands. At a more local scale, meso-ecosystems constitute ecological communities like a temperate broadleaf forest with associated plant and animal species. Micro-ecosystems form subsets of meso-ecosystems that differ in environmental features, for instance subalpine vs lowland varieties of the same forest type. Finally, nano-ecosystems represent small, distinct habitats contained within the previous levels, from a stump rich with fungi to a desert hot spring hosting unique microbes.
This hierarchical view captures ecosystems nested within progressively larger systems ranging from regional biomes down to specialized microhabitats, all interconnected to form the thriving, global biosphere.