COMMUNITY SYSTEM ORGANIZATION

• Community


  Group of interacting species and their physical environment within a specific area
• System


  Structure, composition, and functioning of ecological communities
• Organization


  Refers to the structure, composition, and functioning of ecological communities
• Community system organization involves understanding how different species coexist and interact with each other, as well as how they respond to environmental factors such as climate, resources, and disturbances
• Community ecology


  Studying groups of different species that live together in the same area and interact with each other
• Biodiversity


  The number of interacting species in communities and the complexity of their interactions
• Growth Form and Structure


  • Structures arise within communities as species interact, and food chains, food webs, guilds, and other interactive webs are created
  • The structure and growth of a community are influenced by a variety of biotic (living) and abiotic (non-living) factors
• Biotic Factors


  • Species Interactions: Interactions between species, such as predation, competition, mutualism, and parasitism, play an important role in shaping community structure
  • Keystone species: An organism that helps define an entire ecosystem
• Abiotic factors


  • Climate and weather, along with the composition and nutrients in soil, the physical landscape, and water availability, can all influence the environment's physical structure
  • Disturbances such as natural events like storms and floods, or human impacts like deforestation, can also cause significant changes
• Species Interaction


  The effect that a pair of organisms living together in a community have on each other
• Types of Species Interactions

  • Competition
  • Mutualism
  • Symbiosis
  • Commensalism
  • Parasitism
  • Predation
  • Herbivory
• Competition


  An interaction between organisms or species, in which the fitness of one is lowered by the presence of another
• Forms of Competition


  • Interference competition: When an individual directly alters the resource-attaining behavior of other individuals
  • Exploitation competition: Occurs when individuals interact indirectly as they compete for common resources
  • Apparent competition: Occurs when two individuals that do not directly compete for resources affect each other indirectly by being prey for the same predator
• Mutualism


  An interaction between two or more species, where both species derive a mutual benefit
• Symbiosis


  An interaction characterized by two or more species living purposefully in direct contact with each other
• Commensalism


  An interaction in which one individual benefits while the other is neither helped nor harmed
• Parasitism


  Occurs when one individual, the parasite, benefits from another individual, the host, while harming the host in the process
• Predation


  One organism, the predator, kills and eats another organism, its prey
• Herbivory


  A form of consumption in which an organism principally eats autotrophs such as plants, algae and photosynthesizing bacteria
• Habitat


  The specific physical environment in which a species lives, encompassing the physical factors such as temperature, humidity, soil type, and availability of resources like food and shelter
• Niche


  The role and position a species has within its habitat, including how it meets its needs for survival and reproduction
• Habitats and Niches


  • Habitat Diversity: Communities often consist of multiple habitats, each supporting different species adapted to its specific conditions
  • Niche Partitioning: Within each habitat, species occupy different niches to minimize competition for resources
  • Species Interactions: Species within a community interact with each other through various ecological relationships
  • Succession: Over time, communities may undergo ecological succession, where the composition of species changes in response to environmental disturbances or other factors
• Succession


  The process of ecological change in a community over time following a disturbance, involving a predictable and orderly sequence of species colonization, growth, and replacement
• Types of Succession


  • Primary Succession: Occurs in areas where no soil exists initially
  • Secondary Succession: Occurs in areas where the soil is already present but has been disturbed
• Stages of Succession


  • Pioneer Stage: Characterized by the establishment of pioneer species adapted to harsh environmental conditions
  • Intermediate Stages: As the environment becomes more favorable and conditions change, species composition shifts, and more diverse communities develop
  • Climax Community: Eventually, succession leads to the establishment of a climax community, which represents a relatively stable endpoint of succession under the prevailing environmental conditions
• Ecosystem Services


  The benefits provided by natural ecosystems to humans, encompassing provisioning, regulating, supporting, and cultural services
• Types of Ecosystem Services

  • Provisioning Services: Tangible products provided by ecosystems
  • Regulating Services: Services regulating environmental processes and conditions
  • Supporting Services: Fundamental for the production of other ecosystem services
  • Cultural Services: Non-material benefits provided by ecosystems
• Importance of Ecosystem Services

  • Supporting Livelihoods: They provide food, water, and resources vital for livelihoods
  • Ensuring Food Security: Ecosystems sustain agriculture, fisheries, and forestry
  • Enhancing Quality of Life: They offer recreational opportunities and aesthetic experiences
• Valuation and Economic Importance

  • Quantifying Importance: Recognizes their economic significance and guides sustainable resource management
  • Valuation Methods: Market-based and Non-market
  • Prioritizing Conservation: Identifies high-value ecosystems and allocates resources effectively
  • Informing Decision-Making: Provides insights into trade-offs and guides policymakers
• Threats and Challenges


  • Habitat Destruction: Urbanization, deforestation, and land conversion
  • Pollution: Contamination of air, water, and soil
  • Climate Change: Alteration of climate patterns
  • Overexploitation: Unsustainable use of natural resources
• Conservation and Management


  • Strategies: Protected areas, sustainable practices, ecosystem restoration, community initiatives
  • Examples: Reserves, agroforestry, restoration projects, community involvement
  • Importance: Integrated approaches ensure long-term sustainability
• Biodiversity


  The variety of life on Earth, encompassing all living organisms from microbes to plants to animals
• Aspects of Biodiversity


  • Genetic Diversity: The variety of genes within a species
  • Species Diversity: The variety of different species within a specific area or ecosystem
  • Ecosystem Diversity: The variety of different ecosystems, habitats, and ecological processes across landscapes
  • Temporal Diversity: Changes in biodiversity over time
  • Functional Diversity: The variety of ecological functions performed by different species within an ecosystem