Understanding Biodiversity

• Biodiversity refers to the variety of life forms on Earth and their interdependence

Terms

• Species is a fundamental unit in biology and a basic populational and evolutionary unit
• Ecosystem is a geographic area with plants, animals, and other organisms interacting with weather and landscape to form a bubble of life, containing both biotic (living) and abiotic (nonliving) parts
• Genes is the functional unit of inheritance controlling the transmission and expression of traits
• Wildlife refers to organisms living in a natural environment

Levels of Biodiversity

• Genetic diversity refers to the variation of genes within a species, constituting distinct populations or genetic variations
• Species diversity refers to the variety of species within a region, measured by the number of species
• Ecosystem diversity involves the network of different species in local ecosystems and their dynamic interplay

Benefits of Biodiversity

• Provides food/drink, fuel, medicine, better crop varieties, and industrial materials (consumptive value)
• Offers recreation, education, research, traditional resources, and economic opportunities (non-consumptive value)
• Ecologically, it balances nature, ensures biological productivity, regulates climate, degrades waste, cleans air and water, cycles nutrients, controls pests and diseases, detoxifies soil and sediments, stabilizes land, sequesters carbon, and maintains soil fertility

Megadiverse Regions

• The World Conservation Monitoring Centre recognized 17 megadiverse countries in July 2000
• These countries harbor over 70% of Earth's species, including Australia, Brazil, China, Colombia, Democratic Republic of the Congo, Ecuador, India, Indonesia, Madagascar, Malaysia, Mexico, Papua New Guinea, Peru, the Philippines, South Africa, the United States of America and Venezuela
• Approximately 20% of global plant life, or 50,000 endemic plants, are located in 18 biodiversity hotspots, with mega-diversity nations hosting a relatively large proportion of these hotspots

Philippines as a Megadiverse Country

• Luzon in the Philippines has the highest concentration of unique mammal species, according to a 2016 study
• The Philippines is second in butterfly species endemicity, with 352 endemic species out of 895
• It ranks fifth in mammalian endemicity, with 120 endemic species out of 183 (65%)
• Eighth in reptilian species endemicity, with 170 endemic species out of 258 (66%)

Patterns of Biodiversity

• Species diversity decreases from the equator to the poles (Latitudinal Gradient), with tropics harboring more species
• Solar energy, speciation, and tropical environments contribute to greater biological diversity in the tropics
• Species richness increases with the increase of explored area, but only up to a limit (Species-Area Relationships)

Loss of Biodiversity

• Habitat loss and fragmentation are major drivers of extinction, especially in tropical rain forests
• Alien-species invasion occurs when introduced species become invasive and cause decline or extinction of indigenous species
• Overexploitation, driven by greed, leads to the depletion of natural resources
• Co-extinctions happen when the extinction of one species leads to the extinction of associated species

Threats to Biodiversity

• Development Pressure: Construction, forest industries, hydel/irrigation projects, mining, oil drilling, pollution, resource extraction, and transportation
• Exploitation: Collection by scientific/educational institutions, local authorities, firewood, food gathering, hunting and poaching
• Encroachment: Agriculture, expansion of forest villages, fishery, grazing, habitat change, new settlements, and shifting cultivation
• Human-Induced Disasters: Floods, major oil spills, epidemics, and forest fires
• Management of Natural Resources: Genetic uniformity, inadequate water/food, increased competition, introduction of exotic species, and predation
• Management of Human Resources: People's lifestyle, increasing demands, dilution of traditional values, human harassment, lack of management and inappropriate land use
• Political and Policy Issues: Changes in use/legal status, civil unrest, intercommunity conflict, and military activities
• Climate change is predicted to risk up to 50% of Asia's biodiversity, with potential loss of 88% of coral reefs within 30 years

Deforestation Consequences

• Loss of habitat, reduced pollinator activity, and overall reductions in biodiversity with 3 million hectares of peatland burned over the past decade in Asia
• Net annual forest area loss in Southeast Asia at 2.4M hectares in the 1900; 0.4M hectares in 2000-2006; and 1M hectares in 2005-2010, respectively
• Caused by shifting cultivation and agricultural expansion
• From 2002 to 2020, the Philippines lost 151kha of humid primary forest, comprising 12% of overall tree cover loss, with a decrease of 3.3% in the total area of humid primary forest
• Palawan experienced the most tree cover loss at 163kha

Invasive Alien Species

• It greatly contributes to environmental change and presents constrictions on environmental conservation, economic growth, and sustainable development
• It results in competition with native species for food and domination of the local ecosystem
• Global damage is approximately $1.4 trillion annually

Illegal Wildlife Trade

• Over 100 million animals are hunted for bush meat
• Values range from USD 10 to 20 billion (ASEAN-WEN)
• Approximately 13,000 metric tons of turtles shipped into China every year

Categories of Biodiversity Threat

• Taxa in danger of extinction and whose survival is unlikely, the causal factors continue operation (Endangered)
• Taxa likely to move into endangered category in near future, if the causal factors continue operating (Vulnerable)
• Taxa with small world population that are not at present endangered or vulnerable but are at risk (Rare)
• Threatened the term threatened is used in the conservation for species which fall in one of the above three categories

Recent Issues in Biodiversity

• Depletion of the Philippine Biodiversity
• Mangrove Forests: 149,000 hectares remain from the original 450,000 hectares in 1918.
• Wetlands: more than half of the country's wetlands of international importance covering 14,000 sq. km. are threatened.
• Forests: In 1935, there were 17 million hectares of forests. Today, there are only six million hectares.

Why Conserve Biodiversity?

• Narrowly Utilitarian: Humans derive countless direct goods like, economic benefits from nature
• Ethical Argument: Relates to what we owe to millions of plant, animal and microbe species with whom we share this planet.
• Broadly Utilitarian: Biodiversity plays a major role in many ecosystem services that nature provides.
• Photosynthesis contributes to 20 percent of the total oxygen in the earth's atmosphere, and pollination is another service pollinators layer - bees, bumblebees, birds and bats.

Biodiversity Conservation Methods

• In-Situ Conservation (within natural habitat)
  • Biosphere Reserves
  • National Parks
  • Wildlife Sanctuaries
  • Sacred Forest Causes
• Ex-Situ Conservation (outside natural habitat)
  • Botanical Gardens
  • Zoos
  • Seed/Pollen Banks
  • Gene Banks
  • Tissue Culture