Factors Affecting the Distribution of Organisms

Temperature, rainfall, and relative humidity are the main climatic factors that determine where plants and animals live. Temperature affects how fast organisms grow and reproduce—some creatures thrive in hot places while others prefer cold areas. Rainfall determines water availability, so regions with more rain support more vegetation and animals than dry areas. Relative humidity (moisture in the air) influences how much water organisms lose, affecting which species can survive in different zones.

In Nigeria, you can see this clearly. The Sahel region in the north has low rainfall and high temperatures, supporting only drought-resistant plants like acacia trees and animals like camels. Meanwhile, the southern rainforest experiences high rainfall and humidity, allowing dense vegetation and animals like gorillas to flourish. The middle savanna zone represents a transition between these extremes.

Think of distribution as where organisms live and thrive. Several environmental factors determine which plants and animals can survive in different places. Humidity affects organisms because some need wet conditions while others prefer dry environments. For example, rainforest animals in Nigeria's Cross River State depend on high humidity, while Sahel animals tolerate low moisture levels.

Wind speed and direction influence seed dispersal and affect plant growth. Altitude changes temperature and air pressure, so mountain plants differ from lowland ones. Salinity matters greatly for aquatic life—freshwater organisms cannot survive in salty waters like Nigeria's lagoons, while mangroves tolerate salt.

These factors work together to create different habitats, each supporting specific organisms adapted to those conditions. Understanding these interactions helps explain why you find different species in Lagos compared to Jos.

Organisms live in different places because environmental conditions vary. Turbidity refers to how cloudy water is—high turbidity blocks sunlight, so only shade-loving plants survive. pH measures how acidic or alkaline water and soil are; most organisms prefer neutral conditions between pH 6-8. Acidic soils (low pH) favour plants like azaleas, while alkaline soils suit others.

Edaphic factors include soil texture, moisture, and nutrients. In Nigeria's rainforests, acidic soils support dense vegetation, while northern savanna soils are more alkaline. These differences explain why you find different plants in Lagos forests versus Kano's grasslands. When soil is too acidic, plants cannot absorb enough nutrients; when it's too alkaline, certain minerals become unavailable.

Understanding these factors helps explain biodiversity patterns across Nigeria's different ecosystems.

The places where different living things are found depend on several important factors. Temperature matters greatly because organisms need specific heat conditions to survive. For instance, you won't find polar bears in Nigeria's rainforests because they need cold climates. Rainfall is equally crucial—desert plants like cacti are scarce in areas with heavy rain, while rainforest plants struggle in dry regions. Soil type affects what grows where; acidic soils suit certain plants while alkaline soils suit others. Light availability determines whether organisms thrive; shade-loving ferns won't flourish in direct sunlight. Finally, human activities like farming and mining reshape where organisms can live. In Nigeria, you'll observe that mangrove swamps along our coastlines support different species than our savanna regions due to these combined factors working together.

The Secchi disc is a simple but important tool used to measure water transparency, which directly affects how organisms distribute themselves in aquatic environments. Think of it as a white and black circular disc you lower into water until you can no longer see it—that depth tells you the water clarity. Clear water allows light to penetrate deeper, enabling algae and aquatic plants to grow more extensively. In Lagos Lagoon, for example, areas with high transparency support different fish species compared to murky sections near industrial discharge areas.

Water clarity affects distribution because plants need light for photosynthesis, and animals follow their food sources. Less transparent water limits where photosynthetic organisms can survive, which cascades through the entire food chain. Understanding this concept helps explain why certain creatures cluster in specific aquatic zones.

Abiotic factors are non-living things in the environment that affect where organisms can live. Temperature, rainfall, light, humidity, and soil type are major examples. To study how these factors influence distribution, scientists use instruments to collect accurate data. A thermometer measures temperature, while a rain gauge collects and measures rainfall amounts. These measurements help us understand why certain plants and animals thrive in specific locations.

In Nigeria, you'll notice that mangrove forests grow only in coastal swamp areas where soil is salty and waterlogged, while savanna vegetation dominates drier northern regions with lower rainfall. By measuring rainfall with rain gauges in these regions, we can explain why organisms are distributed differently. Understanding these measurements helps predict where species can survive.

The activities of living organisms greatly shape where other species can survive in their environment. When plants grow densely in an area, they create shade that prevents sunlight-loving species from thriving underneath. Animals also influence distribution through feeding habits—for example, goats grazing heavily in Nigerian savannas can destroy vegetation, making the land unsuitable for species that depend on that plant cover.

Animals create habitats too. Burrowing animals like termites in Northern Nigeria modify soil structure, which affects which plants can grow there. When predators hunt, they control prey populations, indirectly influencing the plants those prey animals eat. Even decomposers breaking down dead matter recycle nutrients that determine soil fertility and plant distribution.

These interactions show that no organism lives in isolation; each one modifies its environment for others.

Distribution refers to how people are spread across different areas. Several factors determine where humans settle and live. Climate is crucial—people prefer regions with moderate temperatures and adequate rainfall. Fertile soil attracts farmers, which is why many Nigerians concentrate in areas like the Middle Belt where farming thrives. Water availability near rivers and coasts encourages settlement since water is essential for drinking and transport. Economic opportunities matter too; cities like Lagos have dense populations because of job availability in commerce and industries. Topography also plays a role—flat, accessible land is preferred over steep mountains. Social factors including cultural heritage and family ties keep people in specific regions. Political stability ensures safety, making people avoid conflict zones. In Nigeria, you'll notice sparse populations in desert areas of the far north, while southern regions are densely populated due to better rainfall, fertile land, and coastal access.

Symbiosis describes the close relationship between two different organisms living together. The three main types are mutualism (both benefit), commensalism (one benefits, the other unaffected), and parasitism (one benefits while harming the other).

A perfect Nigerian example is the relationship between crocodiles and plovers. These birds pick parasites and dead skin from crocodile teeth. The crocodile gets cleaned and stays healthy, while the plover gets food. Both organisms benefit, making this mutualism.

Another example is the tapeworm living inside humans. The tapeworm gets nutrients and shelter, but the human host becomes malnourished. This is parasitism because only the tapeworm gains advantage.

Understanding these relationships helps explain why organisms distribute in certain habitats—they often depend on other species being present. Without their symbiotic partners, many organisms cannot survive in particular environments.