Keanekaragaman hayati - Biologi kelas 10 SMA

Scientific concepts / discoveries / nature phenomena presented

1) Levels of biodiversity

Biodiversity (biological diversity) is the diversity of living things, divided into three levels:

• Genetic diversity (within a species) Variation in genes among individuals of the same species.

  • Examples: different flower colors in Rosa hybrids; different fur/hair colors in Felis catus (domestic cats).

• Species diversity Diversity of different species (often within the same genus or related taxonomic groups).

  • Examples: citrus species such as Citrus reticulata (mandarin), Citrus aurantifolia (lime), Citrus limon (lemon).
  • Example genus: Panthera (leopard, lion, jaguar, tiger).

• Ecosystem diversity Diversity of communities and ecological processes across different habitats/regions.

  • Examples of ecosystems/biomes mentioned: tropical rainforests, deserts, grasslands, pine forests.

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2) Types of ecosystems and ecological zonation

A. Aquatic ecosystems (water-dominated)

Aquatic ecosystems are divided into organism groups based on where organisms live relative to water movement and their position:

• Plankton (drift with currents)

  • Phytoplankton (e.g., algae)
  • Zooplankton (e.g., protozoa)

• Nekton (actively swim against currents)

  • Example: fish

• Nekton-like surface floaters (float on the surface)

  • Examples: water hyacinth; aquatic insects

• Benthos (bentos) (bottom-dwelling)

  • Example: shrimp

• Attached to other organisms (epibionts)

  • Example given: snail (as a reference)

Freshwater ecosystems

Characteristics:

• Low salinity
• Influenced by climate/weather
• Limited light penetration

Divisions:

• Lentik (still water): lakes, swamps
• Lotik (flowing water): rivers, waterfalls

Light-based zones:

• Littoral: shallow; light penetrates
• Limnetic: open water away from the edge where light still penetrates
• Profundal: deep; light does not penetrate

Marine ecosystems (seawater)

Characteristics:

• High salinity
• Less influenced by climate/weather
• Temperature differences between surface and depth
• Ocean currents influence conditions

Light-based zones:

• Photic zone (< ~200 m): light penetrates; photosynthesis possible
• Twilight/Disphotic zone (~200–2,000 m): little light; photosynthesis ineffective
• Aphotic zone (> ~2,000 m): no sunlight; always dark

Depth/sea-area zones mentioned:

• Littoral / tidal: near shore; submerged at high tide
• Neritic: shallow sea < ~200 m (e.g., algae, fish)
• Bathyal: deep sea (~200–2,000 m), limited producers
• Abyssal: > ~2,000 m (predators/detritivores emphasized)

Examples of marine-related ecosystems mentioned:

• Coral reef ecosystem (clear shallow water; organisms associated with coral habitats)
• Deep sea ecosystem / “dark sea trench ecosystem” (no producers emphasized)
• Estuary (mixing between seawater and river water)
• Sandy beach ecosystem
• Rocky beach/coastal boulder ecosystem

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B. Land (terrestrial) ecosystems / biomes

Land ecosystems are described as biomes, determined largely by climate, which is influenced by:

• Latitude (geographical location)
• Altitude

Biomes listed:

• Desert

  • Very low rainfall; high evaporation; low humidity; strong day–night temperature variation
  • Vegetation: xerophytes (e.g., cacti)
  • Fauna: lizards, snakes, camels

• Grassland

  • Irregular rainfall (~25–50 cm/year), poor porosity/drainage
  • Vegetation: grasses
  • Fauna examples: bison, buffalo, zebra, giraffe, lions

• Savanna

  • Grassland with scattered trees
  • Moderate, irregular rainfall; better porosity/drainage than grassland
  • Vegetation example: Acacia
  • Fauna examples: horses, giraffes, lions, elephants

• Tropical rainforest

  • Always wet and humid; very high rainfall (~200–400/450+ cm/year as stated)
  • Sunlight year-round; tall trees (canopy formation; shaded understory)
  • Vegetation: climbing plants; orchids attached to other plants
  • Fauna examples: monkeys, birds, snakes, tigers, wild boars

• Deciduous forest

  • Rainfall fairly even (~75–100 cm/year); lower plant diversity/homogeneity
  • Occurs in regions with four seasons
  • Seasonal physiology: plants lose leaves in winter (photosynthesis reduced due to icy conditions), then regrow in summer
  • Vegetation examples: maple (and another maple-like example mentioned)
  • Fauna examples: bears, foxes, squirrels, raccoons

• Taiga / boreal forest

  • Long winters; short dry seasons; low evaporation
  • Vegetation dominated by conifers (pine/spruce)
  • Fauna examples: black bears, wolves, lynx/mice (as mentioned)

• Tundra

  • Coldest biome: long dark winter; long-day summer; snow/ice cover
  • Vegetation examples: lichens/daliken; sphagnum moss
  • Fauna examples: arctic animals such as polar bears, foxes, walrus, penguin
  • Types:
    • Arctic tundra (e.g., Siberia, Canada, Finland)
    • Alpine tundra (high mountains; example mentioned: Jayawijaya)

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3) Biogeographic distribution of fauna and flora in Indonesia

Fauna distribution is described as separated into three regions using:

• Wallace Line (separates western vs central Indonesia)
• Weber Line (separates eastern vs central Indonesia)

Fauna categories

• Asiatic (western Indonesia): Sumatra, Java, Bali, Kalimantan

  • Traits: large mammals, primates, freshwater fish
  • Examples: tigers (Sumatra), elephants (Sumatra), banteng (Java), orangutans (Kalimantan), peacocks (Java), Bali starlings (Bali)

• Transition (between Asia and Australia): Sulawesi, Maluku, Nusa Tenggara

  • Traits: mixed fauna; high endemism
  • Examples: anoa, maleo, pigs/deer, Komodo dragon, tarsiers

• Australian (eastern part): Papua and nearby small islands

  • Traits: marsupials
  • Examples: tree kangaroos, wallabies, birds of paradise, cassowary, green python

Flora distribution (Malesiana region framework)

Flora is described using the Malesiana region framework attributed to Dutch figures (names given in subtitle as “fanworld and Seo”), grouped into three plant areas:

• Sunda Plain (Asian side; Sumatra–Java–Bali–Kalimantan)
• Sahul Plain (Papua and nearby islands)
• Wallacea / transition (Sulawesi region and transition zone)

Flora examples:

• Sunda Plain: yellow cempaka, pora / “bakal kuning”, nibung, corpse flower, Acacia, Gandaria, tuberose, kasturi tengah, black orchid, etc.
• Wallace (transition): lontar, sandalwood, adzan kali chung, langusei, etc.
• Sahul Plain: matoa (one example given)

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4) Benefits of biodiversity (utilization)

Benefits are grouped into human-use categories:

• Food sources

  • Staple foods (rice, corn, “ethnic potatoes”)
  • Vegetables and fruits (examples listed: carrots, strawberries, mangoes, grapes)

• Clothing/materials

  • Fibers: ramie (Boehmeria? mentioned as “Rami fiber”), sheep wool, cotton

• Shelter/building materials & furniture

  • Roof/house materials (reed/thatched materials, palm leaves)
  • Wood for furniture (coconut, teak, ulin, jackfruit, keruing, bamboo)

• Cultural benefits

  • Religious practices and traditional foods associated with biodiversity
  • Examples mentioned: Eid al-Adha sacrifice animals; Christmas tree pines; ketupat made from coconut leaves or banana leaves; flowers for grave pilgrimages

• Medicinal sources

  • Examples: noni, ginger, seeds for diarrhea treatment, and other remedies mentioned

• Cosmetics

  • Perfumes from flowers (roses, jasmine, Cananga/ylang-ylang)
  • Hair oil and skin products from candlenut, aloe vera, avocado, honey

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5) Loss of biodiversity (causes)

Main causes listed:

• Habitat loss / reduction

  • Driven mainly by human activities such as deforestation

• Climate change

  • Linked to global warming from increasing greenhouse gases

• Environmental pollution

  • Gases like sulfur dioxide (SO₂) and nitrogen dioxide (NO₂)
  • Leads to acid rain (described as containing sulfuric acid), reducing soil fertility and harming plants over time

• Overexploitation

  • Excessive harvesting of high-value species (wood for buildings/furniture; also hunting/trade for animals)
  • Can lead to species decline and extinction

• Invasive (introduced) species

  • Non-native species may proliferate due to lack of natural predators
  • Example given: introduction of goldfish (native to China/Europe per subtitle) into waters in Papua; described as becoming a predator and harming native fish (e.g., rainbow fish)

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6) Biodiversity conservation (preservation)

Conservation is described as efforts to prevent biodiversity/species from going extinct, split into:

• In situ conservation (in natural habitat)

  • Examples: establishing National Parks, nature reserves, wildlife sanctuaries
  • Example species: one-horned rhinoceros in Ujung Kulon

• Ex situ conservation (outside natural habitat)

  • Examples: Taman Safari (zoo setting) and botanical gardens

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Researchers / sources featured

• The subtitle attributes Indonesian flora regional classification to Dutch figures named “Fanworld” and “Seo” (spelling uncertain due to auto-generated captions).