Summary 1 : Environmental Factors

Figure 1.1 Concept Maps

 

 

 

 

ECOLOGY

Ecology (Ecology, oikos = house, logos = study) is a science that studies the abundance and distribution of an organism and its interaction with the environment. The scope of ecological research among other organisms ecology, community ecology, ecosystem ecology, landscape ecology and global ecology. The distribution of species is limited by the spread, behavior, factors biotic (predation, parasitism, competition, and disease) and factor abiotic consisting of physical  factors (temperature, light, soil structure, fire, humidity) and chemical factor (water, oxygen, salinity, pH, soil nutrients).

I.      Biotic factors

Certain species can not survive in the new habitat as a result of negative interactions with other organisms in the form of predation, parasitism, or competition. In addition, it can also be influenced by the presence of other species that are needed by a species (predators, herbivores) in other words, organisms that eat restrict the distribution of organisms that be eaten. The existence or absence of a source of food, parasites, pathogens, and competitors organism can also act as a barrier to the distribution of species.

II.   Abiotic factors

Most of abiotic factors vary with time and space because the environment is spatial heterogeneity (spatial heterogeneity) and temporal heterogeneity (temporal heterogeneity). Although the two regions on earth to experience different conditions, the daily and annual fluctuations of abiotic factors can obscure or clarify these differences. In addition, the organism has the adaptability to face the extreme conditions in a way hibernation or dormancy. The abiotic factors, among others:

1.      Temperature

Temperature effect on the biological processes of an organism. Metabolism of an organism requires a specific temperature. Just a little organism that can maintain an active metabolism at temperatures that are too high or too low. However, there are organisms that can adapt to extreme temperature conditions.

2.         Water

Both species live on land and aquatic needs water. Tidal pose a threat to species living in its waters. While the organism land threatened by drought encourages the organism to adapt.

3.         Salinity

Salinity of water in the environment affect the water balance of the organism through osmosis. Aquatic organisms have the limited osmoregulation ability. Land’s Organism  can excrete excess salt from a special gland or via the feces. However, not all organisms can adapt to high salt levels.

4.         Sunlight

Sunlight is needed by the autotrophic organism for photosynthesis. The quantity of radiation can affect the distribution of autotrophic organisms. Meanwhile, in the aquatic environment, photosynthesis occurs relatively close to the surface (every meter of depth to absorb 45% of red light and blue light 2%). Light that is too high can also threatens living creatures.

5.      Rocks and soil

pH, mineral composition, and physical structure of the rocks and soil limit the distribution of plants and plant eating animals. pH of the soil and water can limit the distribution of organisms directly (acid / alkaline extremes) and indirectly (solubility nutrient and toxic).

Abiotic factors that affect the distribution of organisms vary by climate. The main components of the climate is the temperature, rainfall, sunshine, and wind. Climate patterns such as :

1.      Macro climate

1.   Global Climate Patterns

Global climate patterns are determined by the input of solar energy and the movement of the planets. Spherical shape of the earth cause variations in sunlight intensity according to latitude. At 23.5 ⁰ 23.5 ⁰ LU-LS is a tropical region with sunshine straight so that more heat. While at the LU-60 60 ^{0 0} LS, sunlight slanted so that the heat dispersed in the earth's surface.

2.   Seasonal variations in the intensity of the Sun

Earth tilted on its axis at 23.5 ⁰ to the plane of orbit around the sun. Tropical regions get biggest annual solar radiation input and smallest seasonal variations. By the time the high point of the winter, the Northern Hemisphere tilted away from the sun (day long night short) while the southern hemisphere tilts toward the sun (day length short evening). At the time of the turning point of the fall, equator facing straight toward the sun so that all regions experience 12 hours of daylight and 12 hours of night. At the high point of the summer, the northern hemisphere tilts toward the sun (day long night short) while the Southern Hemisphere tilted away from the sun (day short night long). At the time of the turning point of the spring equator facing straight toward the sun so that all regions experience 12 hours of daylight and 12 hours of night.

3.   Air Circulation Patterns and Global Precipitation

Global solar radiation near the equator triggered global air circulation patterns and rainfall. The high temperatures in the tropics evaporate the water from the earth's surface and cause warm and wet air masses  rises and flows to the poles. The period of rising air releases a lot of water content, causing abundant rainfall in the tropics. Air mass that is high and dry, down toward the earth, absorbs moisture from dry land and create a climate conducive to the development of the desert (region LU-30 ⁰ 30 ⁰ LS). Most of the air which then flows down toward the poles. At the LU-60 60 ^{0 0} LS, the air mass back up and let go of rainfall. Most cold and dry air that rises and then flows to the poles and down and back to the equator. The air absorbs moisture and create a climate in polar regions is not rainy and very cold.

4.   Global Wind Patterns

When the earth rotates, the land around the equator move faster so that the vertical wind bend and create a flow that tends toward the east or the west. Trade winds occur when the wind moves from east to west and occurs in tropical areas. While westerlies occurs when the wind was moving from west to east that occurs in temperate zones.

5.   The effects of Regional, Local and Seasonal at Climate

·      Water body

Ocean currents affect the climate along the coast of the continent by means of heat or cool air masses over the ocean then move onto land. Air heated at the equator and flows along the surface of the Atlantic Ocean to the north, where it cools the water becomes heavier and sinks as far as thousands of meters.

·      Highlands

Mountains affect the amount of sunlight that reaches an area and thus also affect local temperatures and rainfall. This affects the distribution of species. In addition, the increase in height of 1000 m each temperature results in a decrease of approximately 6 ⁰ C equivalent to that generated by the increase of latitude as far as 880 km.

When warm, moist air closer to the mountains, up and cools, releasing moisture into the mountain side in the direction of the wind. In the opposite direction, the air is cooler and dry down, absorb moisture and produce "rain shadows". The desert is formed on the opposite side to the direction of the wind.

·      Change of seasons

Global change day length, solar radiation, and temperature, changes the angle of the sun in a year affect the local environment.

2.      Micro-climate (microclimate)

Microclimate is affected by shading, soil evaporation, or a change in wind patterns. For example, trees in forests often cool microclimate underneath.

BIOME

1.      Waters Biome

Waters biome occupy the largest part of the biosphere around the world. Waters biome are distinguished on freshwater and marine biomes. Sea biomes  (salt content 3%), freshwater biomes (0.1% saline). Stratification of waters biome are :

1. Zones in the lake can be divided into photic zone where there is enough light for photosynthesis aphotic zone is only penetrated by a few rays, and the benthic zone is composed of sand and sediment organic as well as inorganic and is usually found bentos are sources food in the form of detritus.
2. Zones in the sea are distinguished by light penetration and  photic zone. Zones are also distinguished by the distance from the coast and the water depth is inter-tidal zone, netritik, and abisal. Moreover, it also can be divided into open water (pelagic zone) and at the bottom (benthic zone and abisal).

In the oceans and lakes, a thin layer of a sudden temperature change, called the thermocline separating the upper layer of warmer temperatures and a layer in the cooler. 

 

Figure 1.2 Waters biome : Lake

 

Figure 1.3 Waters biome : Sea

2.      Terrestrial Biome

Biome patterns determined by climate,can be modified also by interference (disturbance) that events (storms, fires, and human activity) that transforms a community by getting rid of the organism of the community and changing resource availability. Preparation of Climograph (climograph), plot the temperature and precipitation in certain regions are used to seeing a large impact of climate on the distribution of organisms. Examples of terrestrial biomes include grassland, tropical forest, savanna, desert, chaparral, grasslands, northern conifer forests, temperate broadleaf forest, and tundra. 

Figure 1.4 Terrestrial biome : Mountain

 

Figure 1.5 Terrestrial biome : Forest

 

Figure 1.6 Terrestrial biome : Grassland

Reference

      Campbell, Neil A. Jane B. Reece.Lisa A.Urry.Michael L.Cain.Steven A.Wasserman.Peter V.Minorsky.Robert B.Jackson 2012.BIOLOGI Edisi Kedelapan Jilid 3.Jakarta: Erlangga.

Picture by author (2013)