Biodiversity Loss Week 12 PDF

Biodiversity Loss Biodiversity loss refers to the reduction in species variety, genetic diversity, and ecosystems within an environment. Consequences o Extinction o Failure to respond to environmental changes Drivers of biodiversity loss Climate change: chan...

Biodiversity Loss Biodiversity loss refers to the reduction in species variety, genetic diversity, and ecosystems within an environment. Consequences o Extinction o Failure to respond to environmental changes Drivers of biodiversity loss Climate change: changes in temperature and weather patterns o Impacts habitats o Causes shifts in migration patterns/ breeding seasons/ food availability Invasive species o Disrupt natural food webs by competing for resources or predating on native species. o Spread diseases to which native species have no immunity (e.g., chytrid fungus in amphibians). o Alter habitats (e.g., invasive plants that change soil chemistry). Over-exploitation o Unsustainable harvesting of natural resources faster than species can replenish. Agricultural expansion Jarrod Diamond (evil quartet) 1. Habitat Destruction: o Destruction of natural habitats, often due to deforestation, urbanization, and agriculture. o Results in the loss of shelter, food, and breeding grounds for many species, pushing them toward extinction. 2. Over-exploitation: o Unsustainable hunting, fishing, and harvesting of species for human use. o Depletes populations faster than they can recover, threatening species with extinction. 3. Introduced Species (Invasive Species): o Non-native species disrupt local ecosystems by outcompeting, preying on, or spreading diseases to native species. o Example: The introduction of cane toads in Australia had detrimental eOects on native wildlife. 4. Chains of Extinction: o Extinction of one species can lead to a cascade eOect, causing further extinctions. o Example: The extinction of a keystone species, like a predator or pollinator, disrupts entire ecosystems and aOects other species.  Direct Causes of Biodiversity loss Indirect drivers of Biodiversity Loss o Habitat Change: Population Growth: Increasing Destruction or alteration of human population drives demand habitats directly reduces for resources, leading to habitat available resources for destruction and pollution wildlife. o Exploitation of Species: Technological Advances: New Hunting, fishing, and technologies enable resource harvesting reduce exploitation on a larger scale, such populations. as industrial fishing or mining. o Pollution: Contaminants degrade habitats and directly harm species. o Invasive Species: Outcompete or prey on native species, directly causing declines. o Climate Change: Alters habitats, making them unsuitable for certain species. Extinction Vortex Concept: A self-perpetuating cycle that pushes small, vulnerable populations toward extinction 1. Population Reduction: Declining population size limits genetic diversity. 2. Increased Vulnerability: Low genetic diversity increases susceptibility to disease and environmental changes.  3. Accelerated Decline: Vulnerable populations face higher mortality rates and reduced reproductive success. 4. Extinction: If no intervention occurs, the population is likely to go extinct Why does Biodiversity loss matter to humans?? Ecosystem Services Definition: Ecosystem services are benefits that ecosystems provide to humanity, such as clean water, air, food, and resources. o Pollination: § Pollinators (e.g., bees, butterflies, bats) are essential for the reproduction of many crops. § Without biodiversity, the decline in pollinator species threatens global food security and agricultural productivity. o Water Purification and Climate Regulation: § Wetlands, forests, and other ecosystems filter pollutants and store carbon. § Loss of these ecosystems contributes to water pollution and climate change, which have direct impacts on human health and economic stability. Medical services Biodiversity provides a vast resource for discovering and developing new medicines and treatments. Prevent Biodiversity Loss 3 UN actions Protected Area Expansion Goal: Increase the extent of protected areas, such as national parks, marine reserves, and wildlife sanctuaries. Purpose: Safeguard critical habitats, protect species, and reduce human interference. Sustainable Land and Resource Use Goal: Implement sustainable practices in agriculture, forestry, and fisheries to minimize environmental impact. Purpose: Balance human needs with biodiversity conservation to prevent habitat degradation. Restoration of Degraded Ecosystems Goal: Actively restore ecosystems that have been degraded by human activities. Purpose: Enhance ecosystem services, increase biodiversity, and promote resilience to climate change. Indigenous Agriculture and conservation Concept of Country For many Indigenous Australians, "Country" refers to much more than just the physical land. It encompasses a deep spiritual, cultural, and ancestral connection to the land, water, plants, animals, and sky. Living Entity: Country is seen as a living entity with which Indigenous people share a reciprocal relationship. Role in Identity: Country forms an essential part of Indigenous identity, heritage, and sense of belonging. Ancestors and Spirits: Country is often viewed as being inhabited by ancestral spirits, making it sacred. Traditional resource management Indigenous resource management Human-Centric Approach: Holistic and Reciprocal o Emphasizes the value of Approach: ecosystems primarily for o Views humans as part of the resources and the ecosystem, with a services they provide to responsibility to care for humans (e.g., timber, and maintain balance water, agricultural land). within it. Management Goals: Management Goals: o Focuses on long-term o Sustainable yield and sustainability, respecting resource eOiciency are the natural rhythms and key priorities. cycles of ecosystems. Cultural Burning Benefits of Cultural Burning Reduces Fuel Loads: By reducing the amount of flammable material, cultural burning minimizes the risk of large, intense fires later in the dry season. Promotes Biodiversity: Patchy burns create diverse habitats that support various species and encourage the regeneration of native plants. Protects Ecosystems: Early season burns are less likely to damage mature trees and other key components of the ecosystem, helping maintain the ecological balance. Targeted Areas for Burning Patchwork Burns: Small, patchy burns are conducted to create a mosaic of burned and unburned areas, which prevents large areas of continuous fuel from building up. Strategic Locations: Burning is often focused in areas where fuel loads are highest or where firebreaks are needed to protect communities and sensitive habitats. Anthropocene The Anthropocene is a proposed geological epoch that highlights the significant impact humans have had on Earth's geology, climate, and ecosystems Great acceleration Population growth Industrialisation Urbanisation Rising global temperatures 1. Higher Global Temperatures: Rising temperatures cause polar regions to warm. 2. Sea Ice Melts: Ice melts, reducing the reflective surface area. 3. Decreased Albedo EVect: With less ice, darker ocean surfaces are exposed, absorbing more solar radiation. 4. Increased Heat Absorption: The ocean absorbs more heat, further increasing global temperatures. 5. Repeat Cycle: Higher temperatures cause more sea ice to melt, reinforcing the cycle.